Double Differential Proton and Alpha Emission Cross Sections for Structural Fusion Materials <Superscript>94,95,96</Superscript>Mo

In this study, double differential alpha and proton emission cross sections, which is necessary in determination of heating and damages in structural fusion material research, of ^94,95,96Mo target nuclei have been theoretically calculated by the TALYS 1.8 code at 14.8 MeV neutron incident energy and also compared with available experimental data in EXFOR library. The compound nucleus formation process and pre-equilibrium contribution were found as dominant in the emission of proton and alpha particles, the direct reaction contribution also was seen as dominant in higher particle emission energies.     

Long‐term oropharyngeal colonization by C. albicans in children with cystic fibrosis

This longitudinal prospective study aimed to determine the prevalence of oropharyngeal colonization by C. albicans in children with cystic fibrosis (CF), and observe the continuity of candidal colonization and the changes in production of virulence factors, susceptibility to antifungal agents and RAPD patterns of the isolates. Thirty‐seven children with CF were followed‐up for oropharyngeal C. albicans colonization for 18 months. The colonization rate was detected in 54%. All isolates were susceptible to amphotericin B, but those isolated from one patient were resistant to fluconazole. Biofilm production, secretory acid proteinase, phospholipase and esterase activity rates were 30%, 60%, 75% and 80%, respectively. RAPD analysis with the primers OPE‐03 and OPE‐18 was performed for genotyping. RAPD patterns of the strains isolated from the same patient were related to each other, whereas they were not related with other strains isolated from different patients. Two C. albicans strains isolated from the same patient were found to be unrelated to one another. As a result, long‐lasting colonization of the oropharyngeal mucosa of children with CF by endogenous C. albicans isolates having the same RAPD pattern was demonstrated. Colonization prevalance and development of resistance to antifungal agents and the increased production of virulence factors were not correlated. Copyright © 2013 John Wiley & Sons, Ltd.     

Determination of mechanical and hydraulic properties of polyacrylamide-added bentonite-sand mixtures

Bulletin of Engineering Geology and the Environment - Bentonite-sand mixtures are typically used in engineering applications such as cutoff walls for waste containment facilities or barriers in...     

Dispersion and noise of 1.3 μm multimode lasers in microwavedigital systems

The intensity noise and the performance in a 1.7 Gb/s digital system of 1.3 μm InGaAsP multilongitudinal mode lasers is discussed. The total intensity noise, mode partitioning, and the impact of dispersion on optical noise are measured. It is found that under CW conditions the total simulated emission from unpackaged lasers is inherently quiet, with an integrated optical signal-to-noise ratio (SNR) of 26.8±1.5 dB over a bandwidth of 1.5 GHz and 5 mW/facet. The optical SNR decreased as a function of increasing reflection. Intense mode partitioning decreased the SNR of the main mode by ~20 dB and reduced the effective coherence length to ~2 cm in glass fiber. At 1.7 Gb/s, the power penalities associated with laser bias and fiber dispersion are reported. The best receiver sensitivity is obtained when the laser is biased 1.3 mA below threshold. In general, it is found that as the bit rate increases, the optimum transmitter design becomes progressively more restrictive     

Evaluation of transmission characteristics of chirped DFB lasers indispersive optical fiber

Experimental and analytical results are presented for pulse distortion and receiver penalty associated with wavelength chirp of 1.5 μm distributed feedback (DFB) lasers in the presence of fiber dispersion. An approximate analytical model for dispersion penalty due to chirp is given and shown to provide reasonable agreement with the experimental results obtained for digital transmission at 1.7 Gb/s. The model captures the important features of chirp that lead to dispersion penalty, such as the maximum wavelength excursion, the chirping time, and the energy content at the leading edge of the pulse during chirp. The utility of the model is that the parameters used in it can be readily obtained from single experimental measurements. The limitations of the model are also discussed     

Improving the prediction of page access by using semantically enhanced clustering

There are many parameters that may affect the navigation behaviour of web users. Prediction of the potential next page that may be visited by the web user is important, since this information can be used for prefetching or personalization of the page for that user. One of the successful methods for the determination of the next web page is to construct behaviour models of the users by clustering. The success of clustering is highly correlated with the similarity measure that is used for calculating the similarity among navigation sequences. This work proposes a new approach for determining the next web page by extending the standard clustering with the content-based semantic similarity method. Semantics of web-pages are represented as sets of concepts, and thus, user session are modelled as sequence of sets. As a result, session similarity is defined as an alignment of two sequences of sets. The success of the proposed method has been shown through applying it on real life web log data.     

Probing elastic modulus and depth of bottom-supported inclusions in model tissues using piezoelectric cantilevers

We have experimentally investigated the depth sensitivity limit of a piezoelectric cantilever tissue elastic modulus sensor and simultaneously determined the elastic modulus and the depth of a tumor directly. Using model tissues consisting of bottom-supported modeling clay inclusions of various depths in a gelatin matrix, we empirically determined that the depth sensitivity limit of a piezoelectric cantilever sensor was twice the linear dimension of the indentation area (or the cantilever width). Knowing the depth sensitivity limit of the individual cantilever sensor as input and treating a model tissue that has the gelatin matrix on top and the modeling clay inclusion at the bottom as two springs in series, we showed that the elastic moduli and depths of the hard inclusions could be simultaneously determined with the elastic modulus profiles measured by two cantilevers with different widths as input.     

Design of a Geomembrane-Laminated Geosynthetic Clay Liner on the Slopes of a Mine Tailings Dam in Emet,Turkey

We evaluated the potential use of a geomembrane-laminated geosynthetic clay liner (GCL) along the slopes of a boric acid tailings dam in Emet, Turkey. Even though a compacted clay liner (CCL) had been used at the bottom of the tailings dam, it was not possible to place a CCL along the slopes of the dam due to their steepness. Triaxial permeability tests were conducted on the base GCL without a geomembrane and the results indicated that although the volumetric flow through a cross section of the GCL was measured to be very low initially, it increased after a while due to the interaction of the bentonite in the GCL and the mine leachate. For this reason, using a geomembrane-laminated GCL along the steep slopes was found to be an appropriate solution. The mechanical properties of the barrier material were evaluated by performing a parametric study, including a slope stability analysis and an anchorage design for the geomembrane-laminated GCL. Based on the results, a geomembrane-laminated GCL with appropriate mechanical and hydraulic properties was chosen.     

Some Biochemical Properties of Lipase from Bay Laurel (<Emphasis Type="Italic">Laurus nobilis</Emphasis> L.) Seeds

Lipase was isolated from bay laurel (Laurus nobilis L.) seeds, some biochemical properties were determined. The bay laurel oil was used as the substrate in all experiments. The pH optimum was found to be 8.0 in the presence of this substrate. The temperature optimum was 50 °C. The specific activity of the lipase was found to be 296 U mg protein⁻¹ in optimal conditions. The enzyme activity is quite stable in the range of pH 7.0–10. The enzyme was stable for 1 h at its optimum temperature, and retained about 68% of activity at 60 °C during this time. K _m and V _max values were determined as 0.975 g and 1.298 U mg protein⁻¹, respectively. Also, storage stability and metal effect on lipolytic activity were investigated. Enzyme activity was maintained for 9, 12, and 42 days at room temperature, 4 and −20 °C, respectively. Ca²⁺, Co²⁺, Cu²⁺, Fe²⁺, and Mg²⁺ lightly enhanced bay laurel lipase activity.