Bone regeneration with glass ceramic implants and calcium phosphate cements in a rabbit cranial defect model

Hydroxyapatite cement (BoneSource®) and brushite calcium phosphate cement (chronOS? Inject) were tested for fixation of glass ceramic implants (Bioverit®) in experimentally created cranial defects in 24 adult New Zealand White rabbits. Aim of the in vivo study was to assess and compare the biocompatibility and osseointegration of the implanted materials. Macroscopic and histological evaluations were performed 1 month, 3 months, and 6 months postoperatively. All implanted materials were well tolerated by the surrounding tissue. Both bone cements exhibited osteoconductive properties. Differences could be detected regarding to the rates of cement resorption and new bone formation. The brushite cement was resorbed faster than the hydroxyapatite cement. The chronOS? Inject samples exhibited a higher rate of connective tissue formation and an insufficient osseointegration. BoneSource® was replaced by bone with minimal invasion of connective tissue. New bone formation occurred faster compared to the chronOS? Inject group. Bioverit® implants fixed with BoneSource® were successfully osseointegrated.     

Combined curvelet shrinkage and nonlinear anisotropic diffusion.

In this paper, a diffusion-based curvelet shrinkage is proposed for discontinuity-preserving denoising using a combination of a new tight frame of curvelets with a nonlinear diffusion scheme. In order to suppress the pseudo-Gibbs and curvelet-like artifacts, the conventional shrinkage results are further processed by a projected total variation diffusion, in which only the insignificant curvelet coefficients or high-frequency part of the signal are changed by use of a constrained projection. Numerical experiments from piecewise-smooth to textured images show good performances of the proposed method to recover the shape of edges and important detailed components, in comparison to some existing methods.     

Infants communicate in order to be understood.

Infants intentionally communicate with others from before their 1st birthday. But there is some question about how they understand the communicative process. Do they understand that for their request to work the recipient must both understand the request and be cooperatively disposed to fulfill it? On the basis of the study by Shwe and Markman (1997), we developed a new paradigm that tested whether and how 18-, 24-, and 30-month-old children repair a failed request. Children at all ages repaired their requests in the case of a misunderstanding even if they had obtained the requested object already. They also repaired differently depending on the precise reason for the communicative failure (e.g., misunderstanding the referent versus the communicative intent) and did not repair in the case of correct understanding, even if they did not get the requested object. Thus, from very early in their communicative careers, young children operate with a basic understanding of the mental and cooperative nature of human communication. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Sparse Deconvolution Methods for Ultrasonic NDT

In this work we present two sparse deconvolution methods for nondestructive testing. The first method is a special matching pursuit (MP) algorithm in order to deconvolve the mixed data (signal and noise), and thus to remove the unwanted noise. The second method is based on the approximate Prony method (APM). Both methods employ the sparsity assumption about the measured ultrasonic signal as prior knowledge. The MP algorithm is used to derive a sparse representation of the measured data by a deconvolution and subtraction scheme. An orthogonal variant of the algorithm (OMP) is presented as well. The APM technique also relies on the assumption that the desired signals are sparse linear combinations of (reflections of) the transmitted pulse. For blind deconvolution, where the transducer impulse response is unknown, we offer a general Gaussian echo model whose parameters can be iteratively adjusted to the real measurements. Several test results show that the methods work well even for high noise levels. Further, an outlook for possible applications of these deconvolution methods is given.     

Nonlinear regularized reaction-diffusion filters for denoising of images with textures

Denoising is always a challenging problem in natural imaging and geophysical data processing. In this paper, we consider the denoising of texture images using a nonlinear reaction-diffusion equation and directional wavelet frames. In our model, a curvelet shrinkage is used for regularization of the diffusion process to preserve important features in the diffusion smoothing and a wave atom shrinkage is used as the reaction in order to preserve and enhance interesting oriented textures. We derive a digital reaction-diffusion filter that lives on graphs and show convergence of the corresponding iteration process. Experimental results and comparisons show very good performance of the proposed model for texture-preserving denoising.     

Medium-scale structural genomics: strategies for protein expression and crystallization

While high-throughput methods of protein production and crystallization are beginning to be well documented, owing to the output of large structural genomics programs, medium-throughput methods at the laboratory scale lag behind. In this paper, we report a possible way for an academic laboratory to adapt high-throughput to medium-throughput methods, on the basis of the first results of two projects aimed at solving the 3D structures of Escherichia coli and Mycobacterium tuberculosis (Tb) proteins of unknown function. We have developed sequential and iterative procedures as well as new technical processes for these programs. Our results clearly demonstrate the value of this medium-throughput approach. For instance, in the first 14 months of the E. coli program, 69 out of 108 target genes led to soluble proteins, 36 were brought to crystallization, and 28 yielded crystals; among the latter, 13 led to usable data sets and 9 to structures. These results, still incomplete, might help in planning future directions of expression and crystallization of proteins applied to medium-throughput structural genomics programs.     

Biomass production by thermophilic microorganisms simultaneously using reaction heat

An energy-economic use of reaction heat is possible only if thermophilic microorganisms convert carbon substrates into biomass at temperatures above 65°C. The thermophilic bacterium Bacillus stearothermophilus TP5 was isolated from a man-made hot water reservoir. The highest specific growth rate of 1.6 h^?1 was obtained in continuous cultivation (chemostat) on a glucose-containing nutrient medium at 68°C, pH 6.8 and normal pressure. The highest values for the biomass production rate (3.2 g dm^?3 h^?1) and the biomass yield coefficient (0.39 gg^?1) were obtained at a dilution rate of 1.3 h^?1 (about 80% of the highest specific growth rate) under the above-mentioned conditions. The biomass production rate of the thermophilic bacterium was higher in the chemostat than in the semicontinuous process at normal pressure. The biomass produced in the chemostat at a dilution rate of 0.4 h^?1 contained 71% of protein and 8% of RNA and had an ash content of 6%. The optimum and maximum temperatures of growth were changed by raising the pressure inside the reactor. As a prerequisite for the energy-economic use of the reaction heat, the specific heat production was determined by using a special calorimeter. The ratio of heat production to oxygen consumption (oxy-caloric coefficient) was found to be 13.6 kJ g^?1, which is close to the theoretical value deduced from mass- and energy-balance theory.