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Fast Fourier Methods for Synthetic Aperture Radar Imaging

In synthetic aperture radar one wishes to reconstruct the reflectivity function of a region on the ground from a set of radar measurements taken at several angles. The ground reflectivity is found by interpolating measured samples, which typically lie on a polar grid in frequency space, to an equally spaced rectangular grid in frequency space, then computing an inverse Fourier transform. The class

Phase of solar activity affects response of solar proxy Be-10

The solar proxy Be-10, measured in natural archives, has previously been assumed to lag solar activity by 1-2 yr. This reflects its residence time in the stratosphere where its main source lies. This study, based on a 30-yr global model simulation of the atmospheric transport of Be-10, shows that the stratospheric fraction of production varies significantly with the phase of solar activity. This l

Passive smoking and childhood asthma. Urinary cotinine levels in children with asthma and in referents

Passive exposure to tobacco smoke was assessed in children with asthma (age 3-15) and in referents. There was statistically significantly (P less than 0.0005) higher excretion of the nicotine metabolite, cotinine, in the urine of 49 children with asthma (geometric mean 10 ng/ml) compared with 77 referents (4.8 ng/ml). Maternal smoking was statistically significantly more prevalent among the asthma

Exploring Levers for Improvement of Basic Civil Aviation Training

Popular Abstract in Swedish Även om civil flygindustri har genomgått stora teknologiska och kommersiella förändringar under de senaste årtiondena så har grundläggande civil flygutbildning inte förändrats på motsvarande sätt. Förändringarna inom civilflyget har sällan resulterat i forskningsprogram med inriktning mot grundläggande flygutbildning och denna utbildningsfas har länge varit föremål för Although the civil aviation industry has gone through great technological and commercial change in the last decades, basic civil aviation training has not kept pace accordingly. The changes in civil aviation have rarely resulted in research programs in the field of basic training, which has long received minimal attention from the industry. In the research presented in this thesis, methods for und

High-spin States in the Tz = -1/2 Nucleus 55Ni

High-spin states of the isospin T-z = -1/2 nucleus Ni-55 have been identified for the first time by means of the reaction Si-28(Ar-36,2 alpha n) at 143 MeV beam energy. The GAMMASPHERE array together with ancillary detectors was used to detect gamma rays in coincidence with evaporated light particles. The level scheme of Ni-55 comprising four transitions is compared to its mirror partner Co-55 and

Approximate inverse preconditioners for some large dense random electrostatic interaction matrices

A sparse mesh-neighbour based approximate inverse preconditioner is proposed for a type of dense matrices whose entries come from the evaluation of a slowly decaying free space Green's function at randomly placed points in a unit cell. By approximating distant potential fields originating at closely spaced sources in a certain way, the preconditioner is given properties similar to, or better than,

Animal deoxyribonucleoside kinases: forward and retrograde evolution of their substrate specificity

Abstract Deoxyribonucleoside kinases, which catalyse the phosphorylation of deoxyribonucleosides, are present in several copies in most multicellular organisms and therefore represent an excellent model to study gene duplication and specialisation of the duplicated copies through partitioning of substrate specificity. Recent studies suggest that in the animal lineage one of the progenitor kinases,

Further characterization of the chloroplast grana margins: the non-detergent preparation of granal Photosystem I cannot reduce ferredoxin in the absence of NADP+ reduction

The chloroplast grana margins of spinach thylakoids were isolated by sonication and aqueous-two-phase partitioning and their electron transport properties examined. Photosystem II and I electron transport activities were measured and compared to the appressed and non-appressed grana core and stroma lamellae, respectively, as well as to whole thylakoids. The results show that the PS II complexes in

Models-of-self and models-of-others as related to facial muscle reactions at different levels of cognitive control

The hypotheses of this investigation were based on attachment theory and Bowlby's conception of “internal working models”, supposed to consist of one mainly emotional (model-of-self) and one more conscious cognitive structure (model-of-others), which are assumed to operate at different temporal stages of information processing. Facial muscle reactions in individuals with positive versus negative i

Affinity partitioning of a Cellulomonas fimi beta-mannanase with a mannan-binding module in galactomannan/starch aqueous two-phase system

A new approach in affinity separations was studied by partitioning of Cellulomonas fimi beta-mannanase (EC 3.2.1.78) containing a mannan-binding module in galactomannan/hydroxypropyl starch aqueous two-phase system. Comparison was made with a truncated version of C. fimi beta-mannanase which lacked the mannan-binding module. Results showed that affinity partitioning of the beta-mannanase was achie

Secreted Group IIA Phospholipase A2 Protects Humans Against the Group B Streptococcus: Experimental and Clinical Evidence.

Group B streptococcus (GBS) is a leading neonatal pathogen and a growing cause of invasive disease in the elderly, with clinical manifestations such as pneumonia and sepsis. Despite its clinical importance, little is known about innate immunity against GBS in humans. Here, we analyze the role of human group IIA secreted phospholipase A2 (sPLA2-IIA), a bactericidal enzyme induced during acute infla

Reduced telomere length is not associated with early signs of vascular aging in young men born after intrauterine growth restriction: a paradox?

The mechanisms that increase cardiovascular risk in individuals born small for gestational age (SGA) are not well understood. Telomere shortening has been suggested to be a predictor of disease onset. Our aim was to determine whether impaired intrauterine growth is associated with early signs of vascular aging and whether telomere length could be a biomarker of this pathway.

Blood cadmium, mercury, and lead in children: An international comparison of cities in six European countries, and China, Ecuador, and Morocco

Children's blood-lead concentration (B-Pb) is well studied, but little is known about cadmium (B-Cd) and mercury (B-Hg), in particular for central Europe. Such information is necessary for risk assessment and management. Therefore, we here describe and compare B-Pb, B-Cd and B-Hg in children in six European, and three non-European cities, and identify determinants of these exposures. About 50 scho

Cryogelation of Chitosan Using Noble-Metal Ions: In Situ Formation of Nanoparticles.

One of the purposes of the project was to develop the method of preparation of 3D macroporous hydrogel with a structure of interconnected pores by the use of noncovalent interactions. The combination of chitosan and noble-metal complexes was investigated as cross-linking agents for the preparation of ionic cryogels (ICs). Furthermore, the treatment of the ICs containing gold complex by glutaraldeh

Population-specific Frequencies for LRRK2 Susceptibility Variants in the Genetic Epidemiology of Parkinson's Disease (GEO-PD) Consortium

BackgroundVariants within the leucine-rich repeat kinase 2 gene are recognized as the most frequent genetic cause of Parkinson's disease. Leucine-rich repeat kinase 2 variation related to disease susceptibility displays many features that reflect the nature of complex, late-onset sporadic disorders like Parkinson's disease. MethodsThe Genetic Epidemiology of Parkinson's Disease Consortium recently