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Formation of trioctylamine from octylamine on Au(111)

The adsorption of octylamine on Au(111) under ultrahigh vacuum conditions is investigated. The molecules surprisingly undergo a thermally activated chemical reaction, resulting in formation of trioctylamine as confirmed both by X-ray photoelectron spectroscopy (XPS) and by comparison to the scanning tunneling microscopy (STM) signature of trioctylamine deposited directly onto the surface.

Band functions in the presence of magnetic steps

We complete the analysis of the band functions for two-dimensional magnetic Schrodinger operators with piecewise constant magnetic fields. The discontinuity of the magnetic field can create edge currents that flow along the discontinuity, which have been described by physicists. Properties of these edge currents are directly related to the behavior of the band functions. The effective potential of

A Comparison of Tumor Biology in Primary Ductal Carcinoma In Situ Recurring as Invasive Carcinoma versus a New In Situ.

Introduction. About half of all new ipsilateral events after a primary ductal carcinoma in situ (DCIS) are invasive carcinoma. We studied tumor markers in the primary DCIS in relation to type of event (invasive versus in situ). Methods. Two hundred and sixty-six women with a primary DCIS from two source populations, all with a known ipsilateral event, were included. All new events were regarded as

Lemming-Food Plant Interactions, Density Effects, and Cyclic Dynamics on the Siberian Tundra

Theory predicts that trophic interactions can produce cyclic dynamics of microtine rodents, but that in addition, social interactions are necessary to create the cyclicity. We tested the induced defence hypothesis as a component driving multiannual cycles by analyzing data on Siberian lemming (Lemmus sibiricus Kerr) populations and the levels of trypsin inhibitors (TI) and free proteins (SPP) in t

"The Logic of Care" - Parents' perceptions of the educational process when a child is newly diagnosed with type 1 diabetes

Background: The number of new cases of type 1 diabetes mellitus (T1DM) has increased substantially in recent years and it is now one of the most common long-term endocrine disorders in childhood. In Sweden the child and family are hospitalised in accordance with the national guidelines for one to two weeks at diagnosis. The purpose of this study was to describe parents' perceptions of the educatio

Antibodies against phosphorylcholine are not altered in plasma of patients with Alzheimer's disease

Background: Phosphorylcholine is one of the major epitopes of oxidised low density lipoprotein. Low levels of IgM antibodies against phosphorylcholine (anti-PC) are associated with development of myocardial infarction and stroke. It has been shown that patients with Alzheimer's disease and other dementias have significantly lower serum anti-PC levels compared to controls, suggesting that low level

Bacillus Calmette-Guerin Is Superior to a Combination of Epirubicin and Interferon-alpha 2b in the Intravesical Treatment of Patients with Stage T1 Urinary Bladder Cancer. A Prospective, Randomized, Nordic Study

Background: Bacillus Calmette-Guerin (BCG) instillation is regarded as the most effective bladder-sparing treatment for patients with high-grade T1 tumours and carcinoma in situ (CIS). The major problem with this therapy is the side-effects, making maintenance therapy difficult, even impossible, in a proportion of patients. Thus, alternative schedules and drugs have been proposed. Objective: To co

Forebrain ependymal cells are Notch-dependent and generate neuroblasts and astrocytes after stroke

Neurons are continuously generated from stem cells in discrete regions in the adult mammalian brain. We found that ependymal cells lining the lateral ventricles were quiescent and did not contribute to adult neurogenesis under normal conditions in mice but instead gave rise to neuroblasts and astrocytes in response to stroke. Ependymal cell quiescence was actively maintained by canonical Notch sig

Population structure and genetic diversity in the nannandrous moss Homalothecium lutescens: does the dwarf male system facilitate gene flow?

Nannandry is a sexual system where males ("dwarf males") are much smaller than the conspecific females. Dwarf males occur in a wide range of unrelated organisms but the evolutionary advantages of this condition are poorly understood. The dwarf male sexual system results in differences in the mode of dispersal and establishment as well as the life span between males and females. Such differences mu

The Frantic Gesture of Interpassivity – Maintaining the separation between the corporate and authentic self

Purpose - With the help of Slavoj Zizek's concept of interpassivity, this paper seeks to illustrate the frantic activities performed by employees to maintain a separation between the idea of an authentic self and the idea of a corporate self. Furthermore, this paper aims to illustrate these activities empirically. Design/methodology/approach - The empirical example is based on a case study of thre

A zero-dispersion monochromator and two-beam output for UV Fourier transform absorption spectrometry

The motivation for using a zero-dispersion monochromator as a band-pass filter with a Fourier transform spectrometer is discussed, and the design of such an instrument is presented. Benefits in performance over commercial band-pass filters are demonstrated. In addition the advantages of using the second optical output of the spectrometer are discussed, particularly with respect to absorption spect

Role of Aromatic Side Chains in Amyloid β-Protein Aggregation.

Aggregation of the amyloid β-protein (Aβ) is believed to be involved in Alzheimer's disease pathogenesis. Here we have investigated the importance of the aromatic rings at positions 19 and 20 for the aggregation rate and mechanism by substituting phenylalanine with leucine. Aggregation kinetics were monitored as a function of time and peptide concentration by thioflavin T (ThT) fluorescence, the a

Preparation and characterization of nanometer-thin freestanding polymer foils for laser-ion acceleration

We report on the production and characterization of polymer-based ultra-thin (sub 10 nm) foils suited for experiments on laser-ion acceleration in the regime of radiation pressure acceleration. Beside the remarkable mechanical stability compared with commonly used diamond-like-carbon foils, a very homogeneous layer thickness and a small surface roughness have been achieved. We describe the technic

Storm disturbances in a Swedish forest-A case study comparing monitoring and modelling

A Norway spruce (Picea abies Karst) forest site in southwest Sweden was chosen to study the effects of storm disturbances over the period 1997-2009, during which two storms, 'Lothar' (December 1999) and 'Gudrun' (January 2005), affected the area. Monitored deposition data, soil water chemistry data and forest inventory data were compared with the predictions of an integrated ecosystem model, ForSA

Patterning two-dimensional chalcogenide crystals of Bi2Se3 and In2Se3 and efficient photodetectors.

Patterning of high-quality two-dimensional chalcogenide crystals with unique planar structures and various fascinating electronic properties offers great potential for batch fabrication and integration of electronic and optoelectronic devices. However, it remains a challenge that requires accurate control of the crystallization, thickness, position, orientation and layout. Here we develop a method

Both population size and patch quality affect local extinctions and colonizations.

Currently, the habitat of many species is fragmented, resulting in small local populations with individuals occasionally dispersing between the remaining habitat patches. In a solitary bee metapopulation, extinction probability was related to both local bee population sizes and pollen resources measured as host plant population size. Patch size, on the other hand, had no additional predictive powe