1,830 research outputs found
A mutational hot spot in keratin 10 (KRT 10) in patients with epidermolytic hyperkeratosis
Epidermolytic hyperkeratosis (EHK), (bullous congenital ichthyosiform erythroderma), is an autosomal dominant human skin disorder. Recently, we and others have described mutations in keratins 1 and 10 (K1 and K10) in patients with this disease. Structure-function models predict that these mutations would impair normal filament assembly and function. We have extended our earlier studies to include 8 more incidences of EHK. In half of these families, we were unable to locate a mutation within the rod domains of either K1 or K10. However, polymorphic restriction site and sequence analysis of the other families revealed a mutational hot spot within the 1A alpha-helical segment of K10. These involve Arginine to Histidine, Arginine to Cysteine and Arginine to Leucine substitutions at residue 10 of the rod domain. Interestingly, mutations in the corresponding Arginine residue in keratin K14 have been identified in patients with epidermolysis bullosa simplex. The large number of mutations found at this position in both keratins K10 and K14 suggests that other epithelia cell disorders will be discovered that are caused by the corresponding mutation in related type I keratin gene
Персональная система управления вниманием в интеллектуальных видах деятельности
В данной работе описывается процесс разработки персональной системы управления вниманием в интеллектуальных видах деятельности. Объектом исследования является концентрация внимания, а также способы её улучшения реализуемые посредством объекта промышленного дизайна.This paper describes the process of developing a personal attention management system in intellectual activities. The object of research is the concentration of attention, as well as ways to improve it, implemented through the object of industrial design
Positive-P and Wigner representations for quantum-optical systems with nonorthogonal modes
We generalize the basic concepts of the positive-P and Wigner representations to unstable quantum-optical systems that are based on nonorthogonal quasimodes. This lays the foundation for a quantum description of such systems, such as, for example an unstable cavity laser. We compare both representations by calculating the tunneling times for an unstable resonator optical parametric oscillator
Friction of the surface plasmon by high-energy particle-hole pairs: Are memory effects important?
We show that the dynamics of the surface plasmon in metallic nanoparticles
damped by its interaction with particle-hole excitations can be modelled by a
single degree of freedom coupled to an environment. In this approach, the fast
decrease of the dipole matrix elements that couple the plasmon to particle-hole
pairs with the energy of the excitation allows a separation of the Hilbert
space into low- and high-energy subspaces at a characteristic energy that we
estimate. A picture of the spectrum consisting of a collective excitation built
from low-energy excitations which interacts with high-energy particle-hole
states can be formalised. The high-energy excitations yield an approximate
description of a dissipative environment (or "bath") within a finite confined
system. Estimates for the relevant timescales establish the Markovian character
of the bath dynamics with respect to the surface plasmon evolution for
nanoparticles with a radius larger than about 1 nm.Comment: 8 pages, 1 figure; see also cond-mat/070372
Quantum Statistics of Surface Plasmon Polaritons in Metallic Stripe Waveguides
Single surface plasmon polaritons are excited using photons generated via
spontaneous parametric down-conversion. The mean excitation rates, intensity
correlations and Fock state populations are studied. The observed dependence of
the second order coherence in our experiment is consistent with a linear
uncorrelated Markovian environment in the quantum regime. Our results provide
important information about the effect of loss for assessing the potential of
plasmonic waveguides for future nanophotonic circuitry in the quantum regime.Comment: 21 pages, 6 figures, published in Nano Letters, publication date
(web): March 27 (2012
A Comparative Study of the Formation of Aromatics in Rich Methane Flames Doped by Unsaturated Compounds
For a better modeling of the importance of the different channels leading to
the first aromatic ring, we have compared the structures of laminar rich
premixed methane flames doped with several unsaturated hydrocarbons: allene and
propyne, because they are precursors of propargyl radicals which are well known
as having an important role in forming benzene, 1,3-butadiene to put in
evidence a possible production of benzene due to reactions of C4 compounds,
and, finally, cyclopentene which is a source of cyclopentadienylmethylene
radicals which in turn are expected to easily isomerizes to give benzene. These
flames have been stabilized on a burner at a pressure of 6.7 kPa (50 Torr)
using argon as dilutant, for equivalence ratios (?) from 1.55 to 1.79. A unique
mechanism, including the formation and decomposition of benzene and toluene,
has been used to model the oxidation of allene, propyne, 1,3 butadiene and
cyclopentene. The main reaction pathways of aromatics formation have been
derived from reaction rate and sensitivity analyses and have been compared for
the three types of additives. These combined analyses and comparisons can only
been performed when a unique mechanism is available for all the studied
additives
Tourism policy and destination marketing in developing countries: the chain of influence
Tourism marketers including destination marketing organisations (DMOs) and international tour operators play a pivotal role in destination marketing, especially in creating destination images. These images, apparent in tourist brochures, are designed to influence tourist decision-making and behaviour. This paper proposes the concept of a “chain of influence” in destination marketing and image-making, suggesting that the content of marketing materials is influenced by the priorities of those who design these materials, e.g. tour operators and DMOs. A content analysis of 2,000 pictures from DMO and tour operator brochures revealed synergies and divergence between these marketers. The brochure content was then compared to the South African tourism policy, concluding that the dominant factor in the chain of influence in the South African context is in fact its organic image
The Trade-Off between Phosphorus Recycling and Health Protection during the BSE Crisis in Switzerland. A “Disposal Dilemma”
Phosphorus (P) is an essential, finite resource whose geological, economic, and geopolitical accessibility may become critical in the future. Because P losses from agriculture, sewage and waste have serious environmental impacts such as eutrophication, it would be desirable to close P cycles. However, there may arise dilemmas due to trade-offs with other issues. For instance, recycling of animal bones – containing relatively high amounts of P – was prohibited in Switzerland after the BSE crisis (1989 to 2000) due to perceived health risks. Our analysis indicates that the great- est potentials for closing the P cycle in Switzerland are to reduce P losses in agriculture and to increase P recovery from sewage and waste. Whereas in agriculture significant improvements have been made, the disposal dilemma of animal bones led to diminishing amounts of P being recycled from waste. Based on their risk perception, the involved stakeholders prioritized preventing potential harm to (human) health over maximizing P recycling
Editorial Redox Biology of Exercise
Redox biology is probably the most rapidly expanding field in biology. Indeed, the number of conferences, journals, and books devoted to redox biology is increasing and it is very often seen that major biology journals publish special issues on this area (e.g., Exercise is perhaps one of the most characteristic examples demonstrating that reactive species are not necessarily "harmful" entities, considering that the well-known benefits of regular exercise on muscle function and health are accompanied by repeated episodes of oxidative and nitrosative stress. In addition, an ongoing debate exists in the literature regarding the implications of antioxidant supplementation on physical performance and redox homeostasis. Considering that the redox biology of exercise is by nature multidisciplinary, this special issue is compiled of original and review articles combining chemical, analytical, biochemical, nutritional, physiological, and medical aspects relevant to reactive species biology. Reading through these papers the multiple facets of exercise redox biology are revealed. The review article by E. C. Gomes et al. presents the current state of knowledge on the redox biology of exercise. It provides a comprehensive perspective on the contribution of various intracellular and extracellular sources and the identity of oxidants produced by exercising animals and humans. It also focuses on the possible role of these exercise-induced oxidants in important training adaptations such as angiogenesis, mitochondria biogenesis, and muscle hypertrophy. This article lays the groundwork for the other articles of the special issue that address oxidant effects on exercise performance and redox homeostasis and diseases. Specifically, H. Pan et al. indicated that electrical stimulation of skeletal muscle cells increased the production of reactive species as well as the mRNA and protein levels of interleukin-6. The authors hypothesized that reactive species generation induced by skeletal muscle contraction may be one of the factors regulating musclederived interleukin-6 production and release. Using a more physiological relevant methodology, S. Mrakic-Sposta et al. employed an electron paramagnetic resonance technique for the rapid and noninvasive measurement of reactive species concentration directly in fresh human peripheral blood. Using this innovative approach, they reported that short-term high-intensity exercise increased reactive species production whereas the resting levels of reactive species decreased following supplementation with the antioxidant cofactor α-lipoic acid
- …