508 research outputs found
The correlation of protein peroxidation with morphological changes in experimental oestradiol-induced carcinogenesis
Oestradiol-induced male Syrian hamster carcinogenesis is a well-known experimental
model of human cancer of the breast, ovary and uterus. The pathomechanism
postulated in this model is 4-hydroxylation of oestradiol and further
free radical formation. The same process is suspected in human breast cancer.
Dynamic changes in protein peroxidation were reported during the tumour induction.
In this paper we try to correlate the protein peroxidation markers with
the histopathological progression of the changes. The biochemical and histopathological
evaluations were performed after 1, 3, 6 and 9 months of the
hormone exposition. Significant protein peroxidation was observed as soon as
after 1 month and increased further until the 6th month. After 9 months however,
it was not significantly different from the control. The discrete histopathological
changes after 1 month, progressed into tubular and interstitial hyperplasias
after 3 and 6 months. After 9 months several dysplastic areas, sometimes
with features of carcinoma in situ, were observed. The severe 9-month histopathological
changes did not correlate with the protein peroxidation
Particle-unstable nuclei in the Hartree-Fock theory
Ground state energies and decay widths of particle unstable nuclei are
calculated within the Hartree-Fock approximation by performing a complex
scaling of the many-body Hamiltonian. Through this transformation, the wave
functions of the resonant states become square integrable. The method is
implemented with Skyrme effective interactions. Several Skyrme parametrizations
are tested on four unstable nuclei: 10He, 12O, 26O and 28O.Comment: 5 pages, LaTeX, submitted to Phys. Rev. Let
Three-body Faddeev Calculation for 11Li with Separable Potentials
The halo nucleus Li is treated as a three-body system consisting of an
inert core of Li plus two valence neutrons. The Faddeev equations are
solved using separable potentials to describe the two-body interactions,
corresponding in the n-Li subsystem to a p resonance plus a
virtual s-wave state. The experimental Li energy is taken as input and
the Li transverse momentum distribution in Li is studied.Comment: 6 pages, RevTeX, 1 figur
A selective sweep in a microsporidian parasite Nosema-tolerant honeybee population, Apis mellifera
Nosema is a microsporidian parasite of the honeybee, which infects the epithelial cells of the gut. In Denmark, honeybee
colonies have been selectively bred for the absence of Nosema over decades, resulting in a breeding line that is tolerant toward
Nosema infections. As the tolerance toward the Nosema infection is a result of artificial selection, we screened chromosome 14
for a selective sweep with microsatellite markers, where a major quantitative trait locus (QTL) had been identified to be
involved in the reduction in Nosema spores in the honeybees. By comparing the genetic variability of 10 colonies of the selected
honeybee strain with a population sample from 22 unselected colonies, a selective sweep was revealed within the previously
identified QTL region. The genetic variability of the swept loci was not only reduced in relation to the flanking markers on
chromosome 14 within the selected strain but also significantly reduced compared with the same region in the unselected
honeybees. This confirmed the results of the previous QTL mapping for reduced Nosema infections. The success of the selective
breeding may have driven the selective sweep found in our study.European Union’s Seventh
Framework Program BeeDoc, Deutsche Forschungsgemeinschaft
project DFG SPP 1399 (MO 373/26-1), Romanian
Centre for Bee Biotechnology (RoBeeTech) and China
Scholarship Council.http://onlinelibrary.wiley.com/journal/10.1111/(ISSN)1365-2052hb201
Does computer use pose a hazard for future long-term sickness absence?
The aim of the study was to investigate if weekly duration of computer use predicted sickness absence for more than two weeks at a later time
Breakup Reactions of 11Li within a Three-Body Model
We use a three-body model to investigate breakup reactions of 11Li (n+n+9Li)
on a light target. The interaction parameters are constrained by known
properties of the two-body subsystems, the 11Li binding energy and
fragmentation data. The remaining degrees of freedom are discussed. The
projectile-target interactions are described by phenomenological optical
potentials. The model predicts dependence on beam energy and target,
differences between longitudinal and transverse momentum distributions and
provides absolute values for all computed differential cross sections. We give
an almost complete series of observables and compare with corresponding
measurements. Remarkably good agreement is obtained. The relative neutron-9Li
p-wave content is about 40%. A p-resonance, consistent with measurements at
about 0.5 MeV of width about 0.4 MeV, seems to be necessary. The widths of the
momentum distributions are insensitive to target and beam energy with a
tendency to increase towards lower energies. The transverse momentum
distributions are broader than the longitudinal due to the diffraction process.
The absolute values of the cross sections follow the neutron-target cross
sections and increase strongly for beam energies decreasing below 100 MeV/u.Comment: 19 pages, 14 figures, RevTeX, psfig.st
Fabrication of super-hydrophobic nickel film on copper substrate with improved corrosion inhibition by electrodeposition process
Inspired by the famous “lotus effect”, we have fabricated the super-hydrophobic surfaces with nickel film on copper substrates using a one-step electrodeposition method. By adjusting processing time, water contact angle of as-prepared surfaces can reach as high as 160.3 ± 1.5° with small rolling angle of 3.0 ± 0.5°, showing excellent super-hydrophobicity. After the deposition of nickel coating, the pristine copper surfaces became much rough with packed cauliflower-/thorn-like clusters. This unique surface texture contributed to trapping large amount of air and forming the air cushion underneath the water droplet, which can prevent the liquids contacting the copper substrate. The examination of surface chemical compositions implied that the deposited super-hydrophobic coating consisted of nickel crystals and nickel myristate. In this research, the formation mechanism of the electrodeposited super-hydrophobicity was extensively explained based on the analyses of surface texture and surface chemistry. Moreover, the corrosion resistance of the as-fabricated super-hydrophobic surface was estimated by the potentiodynamic polarization tests as well as the electrochemical impedance spectroscopy (EIS) measurements. The results demonstrate that the super-hydrophobic nickel coating showed excellent corrosion inhibition in simulated seawater solution. The existence of the super-hydrophobic coating could be regarded as a barrier and thus provide a perfect air-liquid interface that inhibits the penetration of the corrosive ions. This facile and effective method of electrodeposition process offers a promising approach for mass production of super-hydrophobic surfaces on various metals
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