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Photochemical mineralization of dissolved organic carbon in lakes of differing pH and humic content

Photochemical mineralization of dissolved organic carbon (DOC) to dissolved inorganic carbon (DIC) was studied in surface water from 10 oligotrophic lakes in Southern Sweden differing in DOC, pH, and iron content. In addition, we studied the effects of acidification on the DOC photoreactivity. Samples from each lake were filtered through 0.2 mum-filters, acidified by one pH unit or kept under ambi

Gestures in spatial descriptions

Most studies of gesture production to date have been based on analyses of narrative discourse in face-to-face interaction. Issues such as the relationship between gesture types and the content of speech, as well as the distribution of particular gesture types across given narrative sequences have been investigated. Depictive gestures, e.g., are frequent where the content concerns the description o

Lifetimes of triaxial superdeformed states in Lu-163 and Lu-164

Lifetimes of states in the yrast superdeformed bands of Lu-163 and Lu-164 were determined in a Doppler-shift attenuation-method experiment. From fractional Doppler shifts and line shapes, average transition quadrupole moments, Q(t) = 8.2(-0.6)(+1.0) b and 7.1(-0.6)(+0.5) 1), were deduced for one of the bands in Lu-163 OX -0.6 and Lu-164, respectively. These values are much larger than the quadrupo

CALLUM Linear Transmitter - Architecture and Circuit Analysis

Popular Abstract in Swedish Upprinnelsen till detta forskningsprojekt ligger i människans önskan att kommunicera. Elektronisk komminikation startade med telegrafen i början av 1800-talet och mot slutet av samma sekel uppfanns telefonen. Till en början var telefonnätet helt passivt, men i samband med upptäckten av elektronröret kopplades förstärkare in i nätet för att lösa problematiken med dämpninThis doctoral dissertation presents a study of linear radio transmitters based on the combined analog locked loop universal modulator (CALLUM) approach. Linear architectures such as CALLUM are very attractive for power-efficient operations, since they have no fundamental limitations prohibiting a 100% efficiency for all envelope levels, without sacrificing the potential of a linear transmission. T

InAs epitaxial lateral overgrowth of W masks

The conditions for successful epitaxial lateral overgrowth of W patterns by InAs using low-pressure metalorganic vapour phase epitaxy were studied. The substrates used were InAs (0 0 1) wafers and the range of growth temperatures between 500 and 600 degrees C. The selective growth was investigated as a function of the V/III-ratio on W-ring test structures and wires oriented in different directions

On the influence of the prior distribution in image reconstruction

Two measures of the influence of the prior distribution p(B) in Bayes estimation are proposed. Both involve comparing with alternative prior distributions proportional to p(theta)(s), for s >= 0. The first one, the influence curve for the prior distribution, is simply the curve of parameter values which are obtained as estimates when the estimation is made using p(B)s instead of p(B). It measures

InAs quantum dots grown on InAlGaAs lattice matched to InP

In this paper, we present InAs quantum dots prepared on an InxAlyGa1-x-yAs surface by metal organic vapor phase epitaxy. Atomic force microscopy measurements indicate that dots grown on material with higher Al content are smaller, and that the local dot densities on step-bunched facets formed on the vicinal (0 0 1) surfaces increase. We find that these dots show luminescence at very long wavelengt

Synthesis and Characterization of Anionic Graft Copolymers Containing Poly(ethylene oxide) Grafts

Anionic graft copolymers were synthesized through grafting of poly(ethylene glycol) monomethyl ether (MPEG) onto terpolymers containing succicinic anhydride groups. The backbone polymers were prepared through radical terpolymerization of maleic anhydride, styrene, and one of the following monomers: methyl methacrylate, ethylhexyl methacrylate, and diethyl fumarate. MPEG of different molecular weig

EULAR Recommendations 2003: an evidence based approach to the management of knee osteoarthritis: Report of a Task Force of the Standing Committee for International Clinical Studies Including Therapeutic Trials (ESCISIT)

Objectives: To update the EULAR recommendations for management of knee osteoarthritis (OA) by an evidence based medicine and expert opinion approach. Methods: The literature search and guidelines were restricted to treatments for knee OA pertaining to clinical and/or radiological OA of any compartment of the knee. Papers for combined treatment of knee and other types of OA were excluded. Medline a

Exact periodic traveling water waves with vorticity

For the classical inviscid water wave problem under the influence of gravity, described by the Euler equation with a free surface over a flat bottom, we construct periodic traveling waves with vorticity. They are symmetric waves whose profiles are monotone between each crest and trough. We use global bifurcation theory to construct a connected set of such solutions. This set contains flat waves as

Patellofemoral osteoarthritis coexistent with tibiofemoral osteoarthritis in a meniscectomy population.

Objectives: To evaluate the frequency of patellofemoral osteoarthritis and its relevance to symptoms and function in a meniscectomy population. Methods: 317 patients with no cruciate ligament injury were evaluated (mean (SD) age, 54 (11) years). They had undergone meniscal resection 15 to 22 years earlier (follow up rate 70%). Standing tibiofemoral and skyline patellofemoral radiographs were grade

Spectroscopy of T=3/2 Mirror Nuclei via Two-step Fragmentation using RISING

Two two-step fragmentation reactions were performed using RISING to populate excited states in A approximate to 50 mirror nuclei near to the proton-drip line, in order to test isospin symmetry. The experiments were designed to observe gamma decays of excited states in the mirror nuclei Ni-53(28)25/Mn-53(25)28, which have a large value of total isospin (T = 3/2). In the continuing off-line analysis

Integrated stratigraphy and chronostratigraphy across the Ypresian-Lutetian transition in the Fortuna Section (Betic Cordillera Spain)

This integrated study across the Ypresian/Lutetian boundary in the Fortuna Section (Spain) allowed us to recognize a bundle of events in the transitional interval between the Ypresian and Lutetian stages. Planktic foraminifera show an apparently continuous succession spanning the planktic foraminiferal zones P9, P10 and P11. Calcareous nannofossils allowed the recognition of the nannofossil subzon

Heat loss to the ground from a building : slab on the ground and cellar

Heated buildings induce a heat flow from the building foundation into the ground. The topic of this thesis is the thermal process in the ground and, in particular, the heat losses from the building to the ground. Foundations of the three types slab on the ground, cellar, and crawl-space are dealt with. The crawl-space is treated in separate report. A reasonably complete theory for the thermal pro