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A comparative analysis of the electron-hole (e-h) excitation mechanism of impurity luminescence has been performed for wide-gap oxides (WGO) and alkali halides crystals (AHC). A low quantum yield of scintillation in WGO with respect to that in AHC is connected with the high value of the average energy needed for the creation of an e-h pair in WGO. In AHC and many WGO, the width of a valence band E

A coordinated movement is easy to recognize, but we know little about how it is achieved. In search of the neural basis of coordination, we present a model of spinocerebellar interactions in which the structure-functional organizing principle is a division of the cerebellum into discrete microcomplexes. Each microcomplex is the recipient of a specific motor error signal-that is, a signal that conv

Poly(propylene oxide)s with a comblike architecture were prepared by using an ethylene-vinyl alcohol copolymer as a macroinitiator for anionic graft polymerisation of propylene oxide. The densely grafted polymers were subsequently modified by capping the terminal hydroxyl groups with hexadecanoyl chloride to produce aggregating polymers. Dilute solution viscometry showed that the hydroxyl and hexa

An eagerly awaited prostate cancer susceptibility gene has been announced. But does the candidate live up to expectations?

Different adsorption phases of iron phthalocyanine (FePc) on highly oriented pyrolitic graphite (HOPG) have been characterized by scanning tunnelling microscopy (STM). Evaporation of FePc onto the graphite (000 1) surface, kept at room temperature. results in the formation of three-dimensional molecular islands. After annealing to 400 degrees C different two-dimensional features Lire identified. d

Background: In obese patients, jejunoileal bypass (JIB) has been used to induce weight reduction. Changes in the neuroendocrine system may be affected by the JIB-operation, because the proximal small intestinal mucosa has a rich supply of endocrine cells and peptidergic nerves. Materials and Methods: In 37 obese patients operated with JIB 1-30 years ago, small intestinal biopsies were taken at the

There are two fundamental aspects of the notion of a self: (i) it is the owner of one's experiences, that to which one's experiences are properly attributed, and (ii) it perceives itself. (ii) is a condition on the self's being capable of attributing experiences to itself or being introspectively aware of its experiences, which constitutes a third, higher-order aspect of the self. I claim that it

Tailbiting codes encoded by convolutional encoders are studied. An explanation is given for the fact that, at low signal-to-noise ratios, a systematic feedback encoder results in fewer decoding bit errors than a nonsystematic feedforward encoder for the same tailbiting code. The analysis is based on a recently introduced code property, namely, the weight density of distance-d codewords. For a give

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Popular Abstract in Swedish Värmebehandling (termoterapi) av tumör baseras på kunskap om den celldödande effekten av värme. Den har begränsats av svårigheten att kontrollera temperaturutbredningen så att en selektiv och tillräcklig effekt erhålls, och detta gäller särskilt djupt belägna tumörer. Interstitiell laser termoterapi (ILT) med Nd:YAG laser är en ny behandlingsform, som ger de tekniska föInterstitial laser thermotherapy (ILT) is a method well suited for selective local destruction of malignant tumours. In the present work, a laser thermotherapy system based on feedback temperature control of energy delivery (through computerised feedback system) was developed. Temperature control was excellent in experiments without carbonization and with preserved light penetration, whereas tempe

Popular Abstract in Swedish Syftet med denna avhandling är att bidra till diskussionen om den s k neolitiseringen av Sverige. Först genom en kritisk granskning av aktuella forskningsrapporter angående tidigneolitikum i framför allt Mellansverige, vilken bl a visar att "jordbruk" var av marginell betydelse under lång tid efter ca 4000 f Kr, samtidigt som idén om "övergången till jordbruk" begreppslThe purpose of this dissertation is to contribute to the discussion of the deeper meaning, in our contemporary context, of the ”neolithization” of Sweden. The basis for the investigation is twofold: * a critical examination of recent research reports dealing mostly with the Early Neolithic of (Middle) Sweden which shows, inter alia, that ”agriculture” was of marginal importance for a very long tim

CONTEXT: The COLIA1 gene is a strong candidate for susceptibility to osteoporosis. The causal genetic variants are currently unclear, but the most likely are functional polymorphisms in the promoter and intron 1 of COLIA1. OBJECTIVE: The objective of the study was to determine whether promoter and intron 1 polymorphisms of COLIA1 or haplotypes defined by these polymorphisms regulate bone mineral d

NOx storage and reduction experiments have been performed with stationary operation of a heavy-duty diesel engine rig. An optimization of the NOx reduction performance has been done using experimental design. The adjustable parameters in this study were cycle time, injection time, injection rate and bypass time (period of reduced flow through catalysts). NOx was reduced by 50-60% (3.3-4.1 g/kWh) w

Lipids have been implicated in ß-cell stimulus-secretion coupling. Thus, lipases in ß-cells would be required to generate coupling factors from intracellular lipids. Indeed, we found that glucose stimulates lipolysis in rodent islets and clonal ß-cells. Lipolysis and diglyceride lipase activity in islets are abolished by orlistat, a pan-lipase inhibitor. Moreover, orlistat dose-dependently inhibit