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The influence of lysine on InP(001) surface ordering and nanowire growth

We report on high resolution photoelectron core level spectroscopy (HRCLS) and scanning tunnelling microscopy (STM) measurements of the decomposition of lysine adsorbed on InP(001) substrates. We find that components from the lysine can be present on the InP surface even after annealing to 600 degrees C and desorption of the native surface oxide. We further observe that while a crystalline surface

On the evolution of corporate forms

The major theme underlying this symposium is the development and growth of many new forms of business associations over the last few decades. These new forms are characterized by a combination of personal freedom from partner/owner liability and far-reaching freedom of contract for partner/owners. The question thus becomes whether this development of new business associations amounts to an extensi

Control of unstable non-minimum-phase delayed systems

The control of systems with long delays, by considering the option of stable/unstable and minimum/non-minimum-phase processes, is a challenging one. Most of the existing solutions do not cover all the situations and, in any case, they lead to complex controllers. Simple controllers, easy to design and tune, are very important in the process industry. In this paper, some control schemes based on a

Predominant selection of T cells specific for the glycosylated collagen type II epitope (263-270) in humanized transgenic mice and in rheumatoid arthritis.

Rheumatoid arthritis (RA) is associated with certain MHC class II alleles and is characterized by a chronic autoimmune response in the joints. Using transgenic mice expressing human DR4 (DRB1*0401) and human CD4, but lacking endogenous MHC class II, we show that posttranslational glycosylation of type II collagen (CII) influences the level of T cell tolerance to this candidate cartilage-specific a

Reduction of GnRH and infertility in the R6/2 mouse model of Huntington's disease.

Reductions in testosterone and luteinizing hormone levels and reduced sexual functions have been reported in Huntington's disease (HD) patients. Atrophy of the reproductive organs and loss of fertility have also been observed in the R6/2 mouse, which is currently the most studied transgenic model of HD. In an effort to define the cause of infertility we studied the expression of gonadotropin-relea

Gene expression profiling in primary breast cancer distinguishes patients developing local recurrence after breast conservation surgery with or without postoperative radiotherapy

Introduction Some patients with breast cancer develop local recurrence after breast-conservation surgery despite postoperative radiotherapy, whereas others remain free of local recurrence even in the absence of radiotherapy. As clinical parameters are insufficient for identifying these two groups of patients, we investigated whether gene expression profiling would add further information. Methods

Antenna subset selection in measured indoor channels

Antenna subset selection can greatly reduce the implementation complexity of multiple input multiple output (MIMO) systems while retaining most of their benefits. This paper investigates the diversity gain and capacity of such systems in wireless personal area networks. Considered scenarios include both the communication between access point to a laptop, and between two handheld devices. We analys

Soft-x-ray spectroscopic investigation of ferromagnetic Co-doped ZnO

The electronic properties of cobalt-doped ZnO were investigated through site-selective and element-sensitive x-ray-absorption spectroscopy in the vicinity of the Co L-2,L-3 edge, the oxygen K edge, and at the Zn L-3 edge. The spectroscopic measurements of the ferromagnetic cobalt-doped ZnO films appear to have additional components in the O K edge x-ray-absorption spectrum not observed in the undo

Radiation efficiency and surface waves for patch antennas on inhomogeneous substrates

Surface wave characteristics and radiation efficiency are calculated for a patch antenna with a given current distribution and located on top of an inhomogeneous, isotropic substrate. The substrate is infinite in the lateral directions and inhomogeneous with respect to the height coordinate. The surface waves in the substrate are analysed using the propagator technique and residue calculus. The pr

Temperature gradients and heat flux measurements in hot pressing of paper

Impulse drying was simulated with a platen press equipped with a heated pressing head. The heat transferred to the wet paper sheet and the temperature gradient achieved in the thickness direction of the sheet during the press pulse were measured. The influence of the basis weight, the applied pressure, and the hot surface temperature on the temperature gradient and the total amount of heat transfe

Cell harvesting by cross-flow microfiltration using a shear-enhanced module

Protein, produced by a bacterial culture of recombinant Vibrio cholerae, was separated from cells in a fermentation broth by cross-flow microfiltration. A new, mechanically agitated (rotational) shear filter, the DMF(TM) filter from Pall, was used to perform the separation. Higher protein recovery and permeate flux than commonly obtained during cell harvesting were demonstrated using sixfold conce

Influence of CrgA on assembly of the cell division protein FtsZ during development of Streptomyces coelicolor

The product of the crgA gene of Streptomyces coelicolor represents a novel family of small proteins. A single orthologous gene is located close to the origin of replication of all fully sequenced actinomycete genomes and borders a conserved gene cluster implicated in cell growth and division. In S. coelicolor, CrgA is important for coordinating growth and cell division in sporogenic hyphae. In thi

High follicular phase luteinizing hormone levels in young healthy BRCA1 mutation carriers: Implications for breast and ovarian cancer risk.

BRCA1 mutation carriers have up to 80% life-time risk of developing breast cancer and 20-40% risk of developing ovarian cancer. High LH levels have been linked to increased risks of both breast and ovarian cancers in some studies and it is unknown whether gonadotropin levels are associated with BRCA1 mutation status. The aim of the study was to explore whether gonadotropin levels were associated w

Consequences of maternal yolk testosterone for offspring development and survival: experimental test in a lizard.

1. Hormone-mediated maternal effects and developmental plasticity are important sources of phenotypic variation, with potential consequences for trait evolution. Yet our understanding of the importance of maternal hormones for offspring fitness in natural populations is very limited, particularly in non-avian species. 2. We experimentally elevated yolk testosterone by injection of a physiologica

pH dependence of the four individual transitions in the catalytic S-cycle during photosynthetic oxygen evolution.

We have investigated the pH dependence for each individual redox transition in the S-cycle of the oxygen evolving complex (OEC) of photosystem II by electron paramagnetic resonance (EPR) spectroscopy. In the experiments, OEC is advanced to the appropriate S-state at normal pH. Then, the pH is rapidly changed, and a new flash is given. The ability to advance to the next S-state in the cycle at diff