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The influence of confining wall profile on quantum interference effects in etched Ga0.25In0.75As/InP billiards

We present measurements of the potential profile of etched GaInAs/InP billiards and show that their energy gradients are an order of magnitude steeper than those of surface-gated GaAs/AlGaAs billiards. Previously observed in GaAs/AlGaAs billiards, fractal conductance fluctuations are predicted to be critically sensitive to the billiard profile. Here we show that, despite the increase in energy gra

Phenotypic heterogeneity in hereditary nonpolyposis colorectal cancer: identical germline mutations associated with variable tumor morphology and immunohistochemical expression.

BACKGROUND: Hereditary non-polyposis colorectal cancer (HNPCC) is associated with high risks for colorectal and endometrial cancer, young age at onset and an increased risk of multiple primary tumours. Colorectal cancer in HNPCC is characterised by poor tumour differentiation, an expanding growth pattern, and a pronounced lymphocytic reaction with tumour-infiltrating lymphocytes. Aims and METHODS:

Revisited Abundance Diagnostics in Quasars: Fe II/Mg II Ratios

Both the Fe II UV emission in the 2000-3000 Å region [Fe II(UV)]and resonance emission line complex of Mg II at 2800 Å areprominent features in quasar spectra. The observed Fe II(UV)/Mg IIemission ratios have been proposed as means to measure the buildup ofthe Fe abundance relative to that of the alpha-elements C, N, O, Ne,and Mg as a function of redshift. The current observed ratios show largesca

Replacement names for three Swedish species of Hieracium (Asteraceae)

While working on a check-list of the Swedish species of Hieracium L. sect. Hieracium and H. sect. Vulgata (Griseb.) Willk. & Lange (now available at www.nrm.se/fbo/chk/ttlista/welcome.htmi), I found that three of the names in current usage were illegitimate, two being later homonyms and one superfluous when published. In this paper avowed substitutes (replacement names) for these names are pro

Integrating needs assessment within next generation e-learning systems: lessons learnt from a case study

In this paper we outline a method for systematically addressing needs assessment (QUALISEM-PEOPLE), alongside a case study of its use within a medium sized, German company. The method was designed in order to provide guidance in analysing skill and role competences, particularly when e-learning systems are being considered for training purposes. The method proved to be successful within the compan

BCVEGPY: an event generator for hadronic production of the B-c meson

We have written a Fortran program BCVEGPY, which is an event generator for the hadronic production of the B-c meson through the dominant hard subprocess gg --> B-c(B-c(*)) + b + c. To achieve a compact program, we have written the amplitude of the subprocess with the particle helicity technique and made it as symmetric as possible, by decomposing the gluon self couplings and then applying the symm

Investigation of the effect of different glassy carbon materials on the performance of Prussian blue based sensors for hydrogen peroxide

Three different kinds of glassy carbon (GC-R, GC-K, GC-G) were equally pretreated, further modified with electrochemically deposited Prussian Blue and used as sensors for hydrogen peroxide at an applied potential of -50 mV (vs. Ag|AgCl). Their performance was evaluated with respect to the following parameters: the coverage and electrochemistry of the electrodeposited Prussian Blue, the sensitivity

Labour-market status and first-time parenthood: The experience of immigrant women in Sweden, 1981-97

This paper investigates the impact of labour-market attachment on first births of foreign-born women in Sweden. The study uses a longitudinal, register-based dataset consisting of the entire population of immigrants from ten nations and a 5-per-cent random sample of natives. The effects of earned income are evident, with increased income levels increasing the probability of becoming a mother for a

The effect of lake trophy on lipid content and PCB concentrations in planktonic food webs

We investigated the influence of trophic status on the lipid content and polychlorinated biphenyl (PCB) concentrations in planktonic food webs from 19 lakes in southern Sweden. The lipid content in phytoplankton (10-45 mum), microzooplankton (45-150 mum) and large macrozooplankton (>500 mum) was negatively related to the total phosphorus (Tot-P) concentration in lakes. The lipid content in macrozo

Effects of halothane on mucociliary activity in vivo

The effect of halothane on mucociliary activity in the rabbit maxillary sinus in vivo was recorded photoelectrically. Administration of halothane (1%, 2% or 4%) into the maxillary sinus induced a temporary acceleration of mucociliary activity. The peak increase (39.1% +/- 9.1%, p < 0.05, n = 5) was seen after the 4% concentration. Long-term exposure (60 minutes) of the maxillary sinus to halothane