Autologous keratinocyte suspension in platelet concentrate accelerates and enhances wound healing - a prospective randomized clinical trial on skin graft donor sites: platelet concentrate and keratinocytes on donor sites.

BACKGROUND: Wound healing involves complex mechanisms, which, if properly chaperoned, can enhance patient recovery. The abilities of platelets and keratinocytes may be harnessed in order to stimulate wound healing through the formation of platelet clots, the release of several growth factors and cytokines, and cell proliferation. The aim of the study was to test whether autologous keratinocyte suspensions in platelet concentrate would improve wound healing. The study was conducted at the Lausanne University Hospital, Switzerland in 45 patients, randomized to three different topical treatment groups: standard treatment serving as control, autologous platelet concentrate (PC) and keratinocytes suspended in autologous platelet concentrate (PC + K). Split thickness skin graft donor sites were chosen on the anterolateral thighs of patients undergoing plastic surgery for a variety of defects. Wound healing was assessed by the duration and quality of the healing process. Pain intensity was evaluated at day five. RESULTS: Healing time was reduced from 13.9 ± 0.5 days (mean ± SEM) in the control group to 7.2 ± 0.2 days in the PC group (P < 0.01). An addition of keratinocytes in suspension further reduced the healing time to 5.7 ± 0.2 days. Pain was reduced in both the PC and PC + K groups. Data showed a statistically detectable advantage of using PC + K over PC alone (P < 0.01). CONCLUSION: The results demonstrate the positive contribution of autologous platelets combined with keratinocytes in stimulating wound healing and reducing pain. This strikingly simple approach could have a significant impact on patient care, especially critically burned victims for whom time is of the essence. CLINICAL TRIAL REGISTRY INFORMATION: Protocol Record Identification Number: 132/03Registry URL: http://www.clinicaltrials.gov

Parameters of the Magnetic Flux inside Coronal Holes

Parameters of magnetic flux distribution inside low-latitude coronal holes (CHs) were analyzed. A statistical study of 44 CHs based on Solar and Heliospheric Observatory (SOHO)/MDI full disk magnetograms and SOHO/EIT 284\AA images showed that the density of the net magnetic flux, $B_{{\rm net}}$, does not correlate with the associated solar wind speeds, $V_x$. Both the area and net flux of CHs correlate with the solar wind speed and the corresponding spatial Pearson correlation coefficients are 0.75 and 0.71, respectively. A possible explanation for the low correlation between $B_{{\rm net}}$ and $V_x$ is proposed. The observed non-correlation might be rooted in the structural complexity of the magnetic field. As a measure of complexity of the magnetic field, the filling factor, $f(r)$, was calculated as a function of spatial scales. In CHs, $f(r)$ was found to be nearly constant at scales above 2 Mm, which indicates a monofractal structural organization and smooth temporal evolution. The magnitude of the filling factor is 0.04 from the Hinode SOT/SP data and 0.07 from the MDI/HR data. The Hinode data show that at scales smaller than 2 Mm, the filling factor decreases rapidly, which means a mutlifractal structure and highly intermittent, burst-like energy release regime. The absence of necessary complexity in CH magnetic fields at scales above 2 Mm seems to be the most plausible reason why the net magnetic flux density does not seem to be related to the solar wind speed: the energy release dynamics, needed for solar wind acceleration, appears to occur at small scales below 1 Mm.Comment: 6 figures, approximately 23 pages. Accepted in Solar Physic

Turning to God in the Face of Ostracism: Effects of Social Exclusion on Religiousness

The present research proposes that individuals who are socially excluded can turn to religion to cope with the experience. Empirical studies conducted to test this hypothesis consistently found that socially excluded persons reported (a) significantly higher levels of religious affiliation (Studies 1, 2, and 4) and (b) stronger intentions to engage in religious behaviors (Study 2) than comparable, nonexcluded individuals. Direct support for the stress-buffering function of religiousness was also found, with a religious prime reducing the aggression-eliciting effects of consequent social rejection (Study 5). These effects were observed in both Christian and Muslim samples, revealing that turning to religion can be a powerful coping response when dealing with social rejection. Theoretical and practical implications of these findings are discussed

Desingularization of vortices for the Euler equation

We study the existence of stationary classical solutions of the incompressible Euler equation in the plane that approximate singular stationnary solutions of this equation. The construction is performed by studying the asymptotics of equation -\eps^2 \Delta u^\eps=(u^\eps-q-\frac{\kappa}{2\pi} \log \frac{1}{\eps})_+^p with Dirichlet boundary conditions and $q$ a given function. We also study the desingularization of pairs of vortices by minimal energy nodal solutions and the desingularization of rotating vortices.Comment: 40 page

United classification of cosmic gamma-ray bursts and their counterparts

United classification of gamma-ray bursts and their counterparts is established on the basis of measured characteristics: photon energy E and emission duration T. The founded interrelation between the mentioned characteristics of events consists in that, as the energy increases, the duration decreases (and vice versa). The given interrelation reflects the nature of the phenomenon and forms the E-T diagram, which represents a natural classification of all observed events in the energy range from 10E9 to 10E-6 eV and in the corresponding interval of durations from about 10E-2 up to 10E8 s. The proposed classification results in the consequences, which are principal for the theory and practical study of the phenomenon.Comment: Keywords Gamma rays: burst

Critical Examination of the "Field-Theoretical Approach" to the Neutron-Antineutron Oscillations in Nuclei

We demonstrate that so called "infrared divergences" which have been discussed in some publications during several years, do not appear within the correct treatment of analytical properties of the transition amplitudes, in particular, of the second order pole structure of the amplitudes describing the $n - \bar n$ transition in nuclei. Explicit calculation with the help of the Feynman diagram technique shows that the neutron-antineutron oscillations are strongly suppressed in the deuteron, as well as in heavier nuclei, in comparison with the oscillations in vacuum. General advantages and some difficulties of the field theoretical methods applied in nuclear theory are reminded for the particular example of the parity violating $np\to d\gamma$ capture amplitude.Comment: 15 pages, 4 figures; prepared for Eur.Phys.J.

On the structure and evolution of a polar crown prominence/filament system

Polar crown prominences are made of chromospheric plasma partially circling the Suns poles between 60 and 70 degree latitude. We aim to diagnose the 3D dynamics of a polar crown prominence using high cadence EUV images from the Solar Dynamics Observatory (SDO)/AIA at 304 and 171A and the Ahead spacecraft of the Solar Terrestrial Relations Observatory (STEREO-A)/EUVI at 195A. Using time series across specific structures we compare flows across the disk in 195A with the prominence dynamics seen on the limb. The densest prominence material forms vertical columns which are separated by many tens of Mm and connected by dynamic bridges of plasma that are clearly visible in 304/171A two-color images. We also observe intermittent but repetitious flows with velocity 15 km/s in the prominence that appear to be associated with EUV bright points on the solar disk. The boundary between the prominence and the overlying cavity appears as a sharp edge. We discuss the structure of the coronal cavity seen both above and around the prominence. SDO/HMI and GONG magnetograms are used to infer the underlying magnetic topology. The evolution and structure of the prominence with respect to the magnetic field seems to agree with the filament linkage model.Comment: 24 pages, 14 figures, Accepted for publication in Solar Physics Journal, Movies can be found at http://www2.mps.mpg.de/data/outgoing/panesar

The Value of Information for Populations in Varying Environments

The notion of information pervades informal descriptions of biological systems, but formal treatments face the problem of defining a quantitative measure of information rooted in a concept of fitness, which is itself an elusive notion. Here, we present a model of population dynamics where this problem is amenable to a mathematical analysis. In the limit where any information about future environmental variations is common to the members of the population, our model is equivalent to known models of financial investment. In this case, the population can be interpreted as a portfolio of financial assets and previous analyses have shown that a key quantity of Shannon's communication theory, the mutual information, sets a fundamental limit on the value of information. We show that this bound can be violated when accounting for features that are irrelevant in finance but inherent to biological systems, such as the stochasticity present at the individual level. This leads us to generalize the measures of uncertainty and information usually encountered in information theory

Explicit formulae in probability and in statistical physics

We consider two aspects of Marc Yor's work that have had an impact in statistical physics: firstly, his results on the windings of planar Brownian motion and their implications for the study of polymers; secondly, his theory of exponential functionals of Levy processes and its connections with disordered systems. Particular emphasis is placed on techniques leading to explicit calculations.Comment: 14 pages, 2 figures. To appear in Seminaire de Probabilites, Special Issue Marc Yo

Renormalizing Partial Differential Equations

In this review paper, we explain how to apply Renormalization Group ideas to the analysis of the long-time asymptotics of solutions of partial differential equations. We illustrate the method on several examples of nonlinear parabolic equations. We discuss many applications, including the stability of profiles and fronts in the Ginzburg-Landau equation, anomalous scaling laws in reaction-diffusion equations, and the shape of a solution near a blow-up point.Comment: 34 pages, Latex; [email protected]; [email protected]