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Luminescence quenching by inter-chain aggregates in substituted polythiophenes

Time-resolved photo luminescence spectra measured in solid films of two polythiophene derivatives with different chain packing allow to distinguish emission of intra-chain excitations from the luminescence of inter-chain aggregates. Aggregate luminescence is red shifted by about 0.1 eV relative to intra-chain emission and shows vibronic coupling to the C=C bond stretch with the Huang-Phys factor o

Registration of emission and transmission whole-body scintillation-camera images

In this work, a method for registration of whole-body (WB) scintillation-camera images is presented. The primary motive for the development is to perform activity quantification using the conjugate view method on an image basis. Accurate image registration is required for sequential anterior and posterior scans, for serial emission images for analysis of the biokinetics, and for transmission and e

ObjectStab - An educational tool for power system stability studies

Traditionally, the simulation of transient and voltage stability in power systems has been constrained to domain-specific tools such as Simpow, PSS/E, ETMSP, and EuroStag. While being efficient and thereby able to simulate large systems, their component models are often encapsulated and difficult or impossible to examine and modify. Also, these simulators often require substantial training and are

Determination of specific surface by the BET method

Abstract in French On peut déterminer la surface spécifique par des mesures d’adsorption des gaz ou des vapeurs d’après la théorie de Brunauer-Emmett-Teller, que l’on examine ici, de même que les techniques expérimentales disponibles: méthodes statiques (volumétriques ou gravimétriques) et dynamiques plus ou moins complexes. En s’aidant d’exemples, on discute l’application de la théorie de B.E.T. The theoretical background of the adsorption isotherm equation of Brunauer, Emmett and Teller is reviewed, together with the experimental techniques available for measuring physical adsorption of gases by solids. Examples are given to show how such measurements are used to determine the specific surface of constructional materials.

Brandrisker och brandskador - hur kan de påverkas. Fire hazards and fire damgages - how to influence them

Det är angeläget, att det schematiska sätt, som nu normalt tillämpas för en dimensionering och utformning av en byggnads eller ett samhälles försvar, på sikt ersätts med ett mer kvalificerat förfarande, som bygger på funktionsbaserade analyser eller bedömningar av brandpåverkade systems reaktion för alternativa möjliga scenarier. Detta är huvudbudskapet i följande rapport, som beylser förutsättnin

Prevalence and type spectrum of human papillomaviruses in healthy skin samples collected in three continents.

In order to investigate whether previous findings of ubiquitous skin papillomavirus infection in Caucasians apply to populations from other parts of the world, skin swab samples from Bangladesh, Japan, Ethiopia and Zambia were analysed in parallel with Swedish samples. The prevalence of HPV DNA in the material from Bangladesh was 68 %, Japan 54 %, Ethiopia 52 %, Zambia 42 % and Sweden 70 %. A grea

Post-gastrectomy osteopenia in the rat: bone structure is preserved by retaining 10%-30% of the oxyntic gland area.

Background: The acid-producing part of the rat stomach (fundus) is rich in endocrine cells, i.e. ECL cells and A-like cells. The ECL cells operate under gastrin control and manufacture histamine, the chromogranin-derived peptide pancreastatin and an unidentified peptide hormone. The A-like cells produce ghrelin, a newly discovered growth hormone-releasing hormone. Surgical removal of the entire gl

Internal hemorrhoids: diagnosis with double-contrast barium enema examinations

The authors retrospectively studied 43 patients suspected of having internal hemorrhoids at double-contrast barium enema examination. At endoscopy, 24 patients (56%) had internal hemorrhoids, four (9%) had other pathologic lesions in the rectum without evidence of hemorrhoids, and 15 (35%) had no reported abnormalities in the rectum. Internal hemorrhoids were found at endoscopy in 10 of 20 patient

The maxillary palp sensory pathway of Orthoptera

Primary sensory projections and arborisations of higher-order neurons associated with the maxillary palps were examined in Tettigoniidae, Gryllidae, Tetrigidae and Acrididae representing the two sub-orders of Orthoptera, Ensifera and Caelifera. Anterograde filling and Golgi impregnation of maxillary receptor neurons revealed two patterns of innervation, the ensiferous and the caeliferous type. In

Tubular secretion of Tamm-Horsfall protein is decreased in type 1 (insulin-dependent) diabetic patients with diabetic nephropathy

Signs of glomerular, proximal and distal tubular dysfunction as well as metabolic control were studied in type 1 diabetes mellitus. To that end, the urinary excretion rates of albumin, sodium, phosphate and Tamm-Horsfall protein as well as HbA1c levels were measured in 20 patients with different degrees of diabetic nephropathy (positive Albustix for several years). Eight diabetic patients with sho

Black tea polyphenols restrict benzopyrene-induced mouse lung cancer progression through inhibition of Cox-2 and induction of caspase-3 expression

Lung cancer is one of the leading causes of cancer related death in most developed and many developing countries of the world. Due to lack of validated screening methods and poor prognosis, treatment of lung cancer has not improved significantly over the last two decades. Therefore the risk of the disease needs to be minimized by preventive measures. One approach for lung cancer prevention envisag

Antifeedant and toxic activity of Adhatoda vasica leaf extract against Spodoptera littoralis (Lep., Noctuidae)

The effect of crude methanolic extracts of Adhatoda vasica leaves on the feeding and performance of Spodoptera littoralis larvae was investigated in the laboratory. Feeding on fresh leaves resulted in 100% mortality of larvae after 26 days of unsubstantial growth. The extract exhibited strong antifeedant and toxic activity against the larvae when applied either on leaf discs or incorporated into a

Signal-averaged P wave analysis for delineation of interatrial conduction - Further validation of the method

ABSTRACT: BACKGROUND: The study was designed to investigate the effect of different measuring methodologies on the estimation of P wave duration. The recording length required to ensure reproducibility in unfiltered, signal-averaged P wave analysis was also investigated. An algorithm for automated classification was designed and its reproducibility of manual P wave morphology classification invest

Properties of Poly(ethylene oxide)-Poly(butylene oxide) Diblock Copolymers at the Interface between Hydrophobic Surfaces and Water

The interactions between molecules of a low molecular weight diblock copolymer of poly(ethylene oxide) (E) and poly(butylene oxide) (B), B8E41, at hydrophobic surfaces were investigated experimentally by using two surface force techniques and ellipsometry. Extended mean-field theory was employed to describe the adsorption of EB diblock copolymers at planar surfaces as well as the forces between su

Broadband UBVRCIC photometry of horizontal-branch and metal-poor candidates from the HK and Hamburg/ESO surveys. I.

We report broadband UBV and/or BVRCIC CCD photometry for a total of 1857 stars in the thick-disk and halo populations of the Galaxy. The majority of our targets were selected as candidate field horizontal-branch or other A-type stars (FHB/ A, N = 576), or candidate low-metallicity stars (N = 1221), from the HK and Hamburg/ESO objective-prism surveys. Similar data for a small number of additional s