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Perturbations in the carbon cycle during the carnian humid episode : Carbonate carbon isotope records from southwestern China and Northern Oman

The Carnian Humid Episode is an interval of prominent climatic changes in the Late Triassic. We studied the carbon isotope (δ13C) geochemistry of carbonates from sections in southwestern China and northern Oman. δ13C records from the Yongyue section (western Guizhou, South China) show a progressive positive shift from 1.4 to 2.8‰ in the early to middle Julian 1 substage. This positive trend is fol

Trade-off Between Antenna Efficiency and Q-Factor

The trade-off between radiation efficiency and antenna bandwidth, expressed in terms of Q-factor, for small antennas is formulated as a multi-objective optimization problem in current distributions of predefined support. Variants on the problem are constructed to demonstrate the consequences of requiring a self-resonant current as opposed to one tuned by an external reactance. The trade-offs are e

Circular dichroism and angular deviation in x-ray absorption spectra of Dy2ScN@C80 single-molecule magnets on h-BN/Rh(111)

Endohedral fullerenes, such as Dy2ScN@C80, are single-molecule magnets with long relaxation times of their magnetization. An open and anisotropic 4f electron shell in the lanthanides (here Dy) imposes a magnetic moment that maintains its orientation at liquid-helium temperatures for macroscopic times. If these molecules shall be used as single-bit information storage elements or for quantum operat

Classification of EEG signals based on mean-square error optimal time-frequency features

This paper illustrates the improvement in accuracy of classification for electroencephalogram (EEG) signals measured during a memory encoding task, by using features based on a mean square error (MSE) optimal time-frequency estimator. The EEG signals are modelled as Locally Stationary Processes, based on the modulation in time of an ordinary stationary covariance function. After estimating the mod

Dialog eller dynamit : Viktor Rydberg och August Strindberg – förtryckets fiender

Trots att Viktor Rydberg och August Strindberg tillhörde olika generationer var de verksamma samtidigt under drygt 25 års tid. För första gången får vi här en grundlig inblick i deras åsikter om varandra samt en uppfattning om de impulser de fått från varandras författarskap. Studien bygger på brevmaterial och ingående textanalyser. Under 1880-talet när motståndet mot konservatismen polariserades,

Effect of type 1 diabetes on school performance in a dynamic world : new analysis exploring Swedish register data

This paper investigates if the effect of type 1 diabetes mellitus (T1DM) on school performance, documented in prior research, has changed in more recent birth cohorts of children using national Swedish population register data. The issue is of interest because management and treatment of the disease have improved over the last decades and, furthermore, because of changes in the educational grading

EPCAM mutation update : Variants associated with congenital tufting enteropathy and Lynch syndrome

The epithelial cell adhesion molecule gene (EPCAM, previously known as TACSTD1 or TROP1) encodes a membrane-bound protein that is localized to the basolateral membrane of epithelial cells and is overexpressed in some tumors. Biallelic mutations in EPCAM cause congenital tufting enteropathy (CTE), which is a rare chronic diarrheal disorder presenting in infancy. Monoallelic deletions of the 3′ end

Modelling and Quality Assessment of Atrial Fibrillatory Waves

This doctoral thesis revolves around the analysis of electrocardiogram (ECG) signals during atrial fibrillation (AF). Special emphasis is put on the atrial fibrillatory waves, sometimes called the f-waves, which is the ECG component reflecting the electrical activity of the atria. The thesis comprises an introduction and five papers that introduce and apply methods on ECG-based analysis of AF. Pap

Omission of doxorubicin from the treatment of stage II-III, intermediate-risk Wilms' tumour (SIOP WT 2001) : an open-label, non-inferiority, randomised controlled trial

BACKGROUND: Before this study started, the standard postoperative chemotherapy regimen for stage II-III Wilms' tumour pretreated with chemotherapy was to include doxorubicin. However, avoidance of doxorubicin-related cardiotoxicity effects is important to improve long-term outcomes for childhood cancers that have excellent prognosis. We aimed to assess whether doxorubicin can be omitted safely fro

The rise of the middle class : The income gap between salaried employees and workers in Sweden, 1830–1935

We present the first comprehensive, long run salary information on Swedish middle-class employees before the twentieth century. Our data include school teachers, professors, clerks, policemen and janitors in Stockholm 1830–1935. We use the new data to compare the annual earnings of these middle-class employees with the annual earnings of farm workers and manufacturing workers. The results show tha

EMF exposure variation among MRI sequences from pediatric examination protocols

The magnetic resonance imaging (MRI) exposure environment is unique due to the mixture and intensity of magnetic fields involved. Current safety regulations are based on well-known acute effects of heating and neuroexcitation while the scientific grounds for possible long-term effects from MRI exposure are lacking. Epidemiological research requires careful exposure characterization, and as a first

The applicability of geoelectrical methods in pre-investigation for construction in rock

Constructing in rock will always involve unforeseen rock conditions. This involves a large risk to a project and can in the end entail delays and extra costs. To minimize the risks, an optimized pre-investigation program has to be conducted where essential information is gathered in order to make the best decisions throughout the construction project. In this work the main focus has been on the ap

Geoelectrical imaging for detection of water migration in a bioreactor landfill

In this paper we describe field investigations of leachate recirculation at a bioreactor landfill using geoelectrical imagining technique (i.e., electrical resistivity) combined with a tracer test. The use of geoelectrical imagining techniques is an established practice for environmental investigations and monitoring of various landfill processes and in recent years also the bioreactor landfill co

Geoelectrical resistivity monitoring for localizing gas at Landfills

In order to assess the potential of electrical resistivity for imaging gas migration at landfills, two relatively well-known sites - one bioreactor landfill and a conventional landfill - have been monitored successively. A three-dimensional resistivity image could be constructed every two hour on both sites. Meteorological parameters were monitored at the same time, with one measurement taken ever

Study of X-ray radiation damage in silicon sensors

The European X-ray Free Electron Laser (XFEL) will deliver 30,000 fully coherent, high brilliance X-ray pulses per second each with a duration below 100 fs. This will allow the recording of diffraction patterns of single complex molecules and the study of ultra-fast processes. Silicon pixel sensors will be used to record the diffraction images. In 3 years of operation the sensors will be exposed t

A new one-step multiplex PCR assay for simultaneous detection and identification of avian haemosporidian parasites

Accurate detection and identification are essential components for epidemiological, ecological, and evolutionary surveys of avian haemosporidian parasites. Microscopy has been used for more than 100 years to detect and identify these parasites; however, this technique requires considerable training and high-level expertise. Several PCR methods with highly sensitive and specific detection capabilit

It’s a long walk : Lasting effects of maternity ward openings on labour market performance

Studies showing that large-scale public health interventions in early life have lasting economic consequences are still scarce and rarely disclose the mechanisms. Being born in a hospital versus having a traditional birth attendant at home represents the most common early life policy change worldwide. Knowing the consequences of this policy is also important given the ongoing enlargement of matern