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Deuteron production in e+e−-annihilation

We argue that ine + e –-annihilation (including -decay) deuteron production should be given by the overlap of the deuteron wave function with the wave function of apn-pair. The production rate depends sensitively upon the size of the production region. Taking into account the strong correlation between protons and neutrons, experimental results for -decay are consistent with the size expected in t

Intervju med Jan Troell

Intervju med Jan Troell om hans filmkarriär, berättarteknik och särskilt hans då aktuella film Så vit som en snö

Phragmites australis and silica cycling in tidal wetlands

Tidal marshes have recently been shown to be important biogenic Si recycling surfaces at the land-sea interface. The role of vegetation in this recycling process has not yet been quantified. In situ and ex situ decomposition experiments were conducted with Phragmites australis stems. In a freshwater tidal marsh, litterbags were incubated at different elevations and during both winter and summer. B

Improved oscillator strengths and wavelengths for Os I and Ir I, and new results on early r-process nucleosynthesis

The radioactive decay of 238U and 232Th has recently been used to determine ages for some of the oldest stars in the Universe. This has highlighted the need for accurate observational constraints on production models for the heaviest r-process elements which might serve as stable references, notably osmium and iridium. In order to provide a firmer basis for the observed abundances, we have perform

Evaluation of the visual pathway with ERG, mfERG and mfVEP in inherited eye disorders

This thesis will describe the clinical phenotypes, with emphasis on electrophysiology, in patients with different hereditary eye diseases and to further evaluate and modify the mfVEP technique for clinical use. Bothnia Dystrophy is a tapetoretinal disorder with a mutation in the RLBP1 gene. Early in the disease the fundus may have a normal appearance. The full-field ERG demonstrates an absence of

A new approach to the phase behavior of oppositely charged polymers and surfactants

The complex salt (ionic surfactant + polymeric counterion) cetyltrimethylammonium polyacrylate (CTAPA) has been synthesized, and its aqueous mixtures with cetyltrimethylammonium bromide (CTABr) have been studied. These mixtures differ from conventional oppositely charged polymer/surfactant mixtures in that the conventional counterion of the polyion (usually sodium, for the polyacrylate) is absent,

Plum-pudding gels as a platform for drug delivery: Understanding the effects of the different components on the diffusion behavior of solutes

The internal structure of composite gels made of responsive microgel particles inserted into a bulk hydrogel (N-isopropylacrylamide microgel particles in a cross-linked dimethylacrylamide matrix) has been investigated from the diffusion behavior of poly(ethylene glycol) (PEG) probes through the network, in the absence of specific interactions between the diffusing molecules and the system. The eff

Comparison of clinical and physical measures of image quality in chest and pelvis computed radiography at different tube voltages

The aim of this work was to study the dependence of image quality in digital chest and pelvis radiography on tube voltage, and to explore correlations between clinical and physical measures of image quality. The effect on image quality of tube voltage in these two examinations was assessed using two methods. The first method relies on radiologists' observations of images of an anthropomorphic phan

Levels of neutrophil elastase and cathepsin B activities, and cystatins in human sputum: relationship to inflammation

Sputum samples from 25 patients with bronchiectasis were assayed enzymatically for myeloperoxidase, neutrophil elastase and cathepsin B, and immunologically for cystatin A, cystatin B, cystatin C, cystatin S and kininogen. High myeloperoxidase and neutrophil elastase levels were found in those sputum samples that were assessed visually to be purulent. These samples were also found to contain high

Characterization of atrial fibrillation using the surface ECG: time-dependent spectral properties

Time-frequency analysis is considered for characterizing atrial fibrillation in the surface electrocardiogram (ECG). Variations in fundamental frequency of the fibrillatory waves are tracked by using different time-frequency distributions which are appropriate to short- and long-term variations. The cross Wigner-Ville distribution is found to be particularly useful for short-term analysis due to i

Determination of wound strength for quantitation of skin damage after pressure ischemia. An experimental study in rabbits

Rabbits skin folds were placed in plexiglass chambers enabling control of the skin fold temperature during cuff compression (200 mmHg) for 4 hours. In 10 animals the skin folds were kept at 36 degrees C - in another 10 animals the skin fold temperature was lowered to 10 degrees C. To quantitate the skin injury caused by the pressure ischemia a standardized wound was made, and immediately closed, a

Discrete Methods used in Graph Theory and Linear Programming

The content of the thesis is divided into two parts; graph theory and linear programming. The main results in the first part concerns extremal graph theory. Here we want to determine the number of edges in a graph needed to ensure the existence of certain local structures. Upper and lower bounds are given for the number of edges in a graph to ensure triangles and quadrilaterals respectively, when

Conceptual spaces as a framework for knowledge representation

The dominating models of information processes have been based on symbolic representations of information and knowledge. During the last decades, a varietyof non-symbolic models have been proposed as superior. The prime examples of models within the non-symbolic approach are neural networks. However, to a large extent theylac k a higher-level theoryof representation. In this paper, conceptual spac

Reducing arrhythmogenic effects in the isolated heart enriching roentgen contrast media with electrolytes. Survey and present state

A review of the literature on the effects of adding electrolytes to ionic as well as nonionic contrast media (CM) in the isolated heart model reveals that both ionic and nonionic CM favor from such addtion, if the added electrolytes are balanced with respect to each other. By enriching nonionic monomeric as well as dimeric CM with such a balanced electrolyte solution, the risk of ventricular fibri