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Nanowire single-electron memory

We demonstrate storage of electrons in semiconductor nanowires epitaxially grown from Au nanoparticles. The nanowires contain multiple tunnel junctions (MTJs) of InP barriers and InAs quantum dots designed such that the metal seed particles act as storage nodes. By positioning a second nanowire close to the seed particle it is possible to detect tunneling of individual electrons through the MTJ at

A fast correlation attack on LILI-128

In this paper we demonstrate a fast correlation attack on the recently proposed stream cipher LILI-128. The attack has complexity around 2(71) bit operations assuming a received sequence of length around 2(30) bits and a precomputation phase of complexity 2(79) table lookups. This complexity is significantly lower than 2(112), which was conjectured by the inventors of LILI-128 to be a lower bound

Speciation by distance in a ring species.

Ring species, which consist of two reproductively isolated forms connected by a chain of intergrading populations, have often been described as examples of speciation despite gene flow between populations, but this has never been demonstrated. We used amplified fragment length polymorphism (AFLP) markers to study gene flow in greenish warblers (Phylloscopus trochiloides). These genetic markers sho

Direct Propane Ammoxidation to Acrylonitrile: Kinetics and Nature of the Active Phase

The kinetics of the direct synthesis of acrylonitrile from propane on V-Sb-Al-(W) mixed oxides indicate that acrylonitrile (ACN) forms by two parallel pathways, one directly from propane and the second, which is the prevalent path, through the intermediate formation of propylene (C3=). The limiting factor in the formation of ACN is the relative slowness of the step of allylic oxidation to ACN of t

Biochemical Studies of Semenogelins with Emphasis on Zinc-Binding Properties

Semenogelins I and II (SgI and SgII) are homologous and rapidly evolving proteins that have a repetitive primary structure and are synthesized mainly in the seminal vesicles. Upon ejaculation, a gelatinous coagulum is formed when the semenogelin-rich secretion from the seminal vesicles is mixed with the prostate secretion, which contains high concentrations of zinc(II) and proteases. These proteas

Polyarteritis nodosa when applying the Chapel Hill nomenclature--a descriptive study on ten patients.

Objectives. Polyarteritis nodosa (PAN) is a term that has been used to describe a wide variety of vasculitic conditions. In 1994, the Chapel Hill Consensus Conference on the nomenclature of systemic vasculitides proposed that the name classical PAN should be restricted to diseases where there is arteritis in small and medium-sized arteries without the involvement of smaller vessels. Our aim was to

Genetically engineered peptide fusions for improved protein partitioning in aqueous two-phase systems - Effect of fusion localization on endoglucanase I of Trichoderma reesei

Genetic engineering has been used for fusion of the peptide tag, Trp-Pro-Trp-Pro, on a protein to study the effect on partitioning in aqueous two-phase systems. As target protein for the fusions the cellulase, endoglucanase I (endo-1,4-β-d-glucan-4-glucanohydrolase, EC 3.2.1.4, EGI, Cel7B) of Trichoderma reesei was used. For the first time a glycosylated two-domain enzyme has been utilized for add

Kinetics of lung clearance of 99mTc-DTPA in smoking patients with sarcoidosis compared to healthy smokers.

Investigation of lung clearance of 99mTc-labelled diethylene triamine penta-acetic acid (DTPA) in smoking sarcoid patients has been impeded by difficulties to differ between pathology of clearance kinetics caused by sarcoidosis and by smoking. This study explores the kinetics of lung clearance of 99mTc-DTPA in 15 current smokers with intrathoracic sarcoidosis. The results are compared with finding

Fracture rate in a population-based sample of men in Reykjavik

The population-based Reykjavik Heart Study, started in 1967, aims at finding and evaluating risk factors for cardiovascular diseases. It included 4,137 men born between 1907 and 1934 and we examined all fractures recorded in these subjects from January 1977 until the end of December 2000, or death. Their mean age at the start of this study was 54 (42-69) years and the mean follow-up time 19 years.

The organization of articulator gestures: A comparison of Swedish, Bulgarian and Greenlandic.

This paper reports speech articulator gestures in Swedish, Bulgarian, and Greenlandic to study universal and language-specific components in articulation. This work is based on analysis of movements of individual articulators from x-ray motion films of speech, and continues from previous reports from this study by Wood [J. Phon. 7, 25–43 (1979); 19, 281–292 (1991); Proc. 3rd Conf. I.C.P.L.A., 191–

Measure-based classifier performance evaluation

The concept of measure functions for classifier performance is suggested. This concept provides an alternative way of selecting and evaluating learned classifiers, and it allows us to define the learning problem as a computational problem.

Autoimmune hepatitis among fertile women: Strategies during pregnancy and breastfeeding?

Objective. In published studies there is a lack of data about the risks, management and how women with autoimmune hepatitis (AIH) decide on and are advised about pregnancy. The aim of this study was to investigate how women with AIH consider pregnancies, are advised and pharmacologically treated, as well as the outcome. Material and methods. A questionnaire was mailed to 128 women with AIH diagnos

Effects of Vagus Nerve Stimulation and Ketogenic Diet on Quality of Life and Changes in EEG and Sleep

Popular Abstract in Swedish De flesta barn som insjuknar i epilepsi tillfrisknar eller blir anfallsfria med hjälp av antiepileptisk medicin. Hos drygt en fjärde del av barnen blir epilepsin svårbehandlad och anfallskontroll är svår att uppnå. Dessa barn ska i första hand erbjudas möjlighet till epilepsikirurgisk utredning och behandling. När epilepsikirurgisk behandling inte är möjlig att utföra eWhen anti-epileptic drugs fail, and epilepsy surgery is found unfeasible or ineffective, there remains a group of at least 25% of children with epilepsy in whom seizure control cannot be achieved. Vagus nerve stimulation (VNS) is an adjunctive treatment for medically refractory epilepsy. It is an implantable, multi-programmable pulse generator that delivers current electrical stimulation to the va

Ion channel control of phasic insulin secretion.

Glucose-stimulated insulin secretion exhibits a biphasic pattern. The mechanism underling biphasic insulin secretion is not fully understood, but consensus exists that an elevation in [Ca2+]i is required for both first- and second-phase insulin secretion. The molecular identity of the pancreatic β-cell L-type Ca2+ channel has not been established and it has variably been reported to be CaV1.2 (α1C

Synthesis of gamma-carboxylated polypeptides by alpha-cells of the pancreatic islets

gamma -Carboxylated proteins were detected in normal human pancreas by immunohistochemistry with a monoclonal antibody (M3B) specific for gamma -carboxyglutamyl residues, Staining appeared to be localized to the glucagon-secreting alpha -cells in the islets of Langerhans, Consistent with this, sections from a glucagonoma were stained much more intensely with the M3B antibody than those from an ins

Wigner-von Neumann perturbations of a periodic potential: spectral singularities in bands

Wigner-von Neumann type perturbations of the periodic one-dimensional Schrodinger operator are considered. The asymptotics of the solution to the generalized eigenfunction equation is investigated. It is proven that a subordinated solution and therefore art embedded eigenvalue may occur at the points of the absolutely continuous spectrum satisfying a certain resonance (quantization) condition betw