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This study was aimed to assess the impact-enriched Saccharomyces cerevisiae with organic selenium addition in finishing lambs on fatty acid composition and physicochemical meat characteristics. Eighteen five-month-old Pelibuey female lambs were fed the same diet for 60 days. Animals were assigned a completely random design of three treatments, control (Se0) without the addition of selenium-yeast or supplemented with 0.35 ppm of selenium-yeast (Se35) and with 0.60 ppm of selenium-yeast (Se60). Lambs were slaughtered at an average weight of 39.5 ± 4.41 kg. Feed intake and meat water holding capacity were decreased (P = 0.001) in Se35 lambs, whereas meat moisture and fat were decreased (P = 0.002) in Se60 lambs. However, meat carbohydrates were increased (P = 0.001) in Se60 lambs. It is concluded that consumption of selenium-yeast in lambs did not alter the productive variables nor the fatty acid composition, though, the fat content is lower, and the carbohydrates are higher in physicochemical meat characteristics. [ABSTRACT FROM AUTHOR]

Nowadays, the physical analogy in biology has become a desirable research domain for academics. Here, we discussed many exciting features regarding the biological system that could help us to understand the underlying mechanism inside it. This manuscript focuses on the soliton/Bloch wave concept along with the periodic active protein polarized dendrite. The velocity of the existent soliton wave is identified by considering the transmission line model of protein polarized dendrite as a dielectric waveguide. This paper aims to understand and explore the mechanisms of biological rhythms and the role of neural oscillations and synchrony in information processing. [ABSTRACT FROM AUTHOR]

Obtaining silicon-based photonic-structures in the ultraviolet range would expand the wavelength bandwidth of silicon technology, where it is normally forbidden. Herein, we fabricated porous silicon microcavities by electrochemical etching of alternating high and low refraction index layers; and were carefully subjected to two stages of dry oxidation at 350 °C for 30 minutes and 900 °C, with different oxidation times. In this way, we obtained oxidized porous silicon that induces a shift of a localized mode in the ultraviolet region. The presence of Si-O-Si bonds was made clear by FTIR absorbance spectra. High-quality oxidized microcavities were shown by SEM, where their mechanical stability was clearly visible. We used an effective medium model to predict the refractive index and optical properties of the microcavities. The model can use either two or three components (Si, SiO2, and air). The latter predicts that the microcavities are made almost completely of SiO2, implying less photon losses in the structure. The theoretical photonic-bandgap structure and localized photonic mode location showed that the experimental spectral peaks within the UV photonic bandgap are indeed localized modes. These results support that our oxidation process is very advantageous to obtain complex photonic structures in the UV region. [ABSTRACT FROM AUTHOR]

The thermal effusivity of gold, aluminum, and copper thin films of nanometric thickness (20 nm to 200 nm) was investigated in terms of the films' thickness. The metallic thin films were deposited onto glass substrates by thermal evaporation, and the thermal effusivity was estimated by using experimental parameters such as the specific heat, thermal conductivity, and thermal diffusivity values obtained at room conditions. The specific heat, thermal conductivity, and thermal diffusivity values of the metallic thin films are determined with a methodology based on the behavior of the thermal profiles of the films when electrical pulses of few microseconds are applied at room conditions. For all the investigated materials, the thermal effusivity decreases with decreased thickness. The thermal effusivity values estimated by the presented methodology are consistent with other reported values obtained under vacuum conditions and more elaborated methodologies. [ABSTRACT FROM AUTHOR]

Optical tweezers is an example how to use light to generate a physical force. They have been used to levitate viruses, bacteria, cells, and sub cellular organisms. Nonetheless it would be beneficial to use such force to develop a new kind of applications. However the radiation pressure usually is small to think inmoving larger objects. Currently, there is some research investigating novel photonic working principles to generate a higher force. Here, we studied theoretically and experimentally the induction of electromagnetic forces in one-dimensional photonic crystals when light impinges on the off-axis direction. The photonic structure consists of a micro-cavity like structure formed of two one-dimensional photonic crystals made of free-standing porous silicon, separated by a variable air gap and the working wavelength is 633 nm. We show experimental evidence of this force when the photonic structure is capable of making auto-oscillations and forced-oscillations. We measured peak displacements and velocities ranging from2 up to 35 microns and 0.4 up to 2.1 mm/s with a power of 13 mW. Recent evidence showed that giant resonant light forces could induce average velocity values of 0.45 mm/s in microspheres embedded in water with 43 mW light power. [ABSTRACT FROM AUTHOR]

The final use that may be given to biosolids that result from the treatment of residual municipal waters depends on their physicochemical and microbiological characteristics. Their organic matter content and wealth of essential elements may allow their use for agricultural fertilization purposes. The objective of this research project was to evaluate the physicochemical interactions between soil treated with biosolids and compost from municipal residual waters, and the nutritional parameters of broad bean seeds ( Vicia faba L.). The studied area is located in the central region of the Mexican Republic. The biosolids were treated with aerated static pile composting. The experimental work was performed in the area surrounding the East Toluca Macroplant, where nine 2 × 3 m plots were defined and distributed in a Latin square; 3 plots were used as controls (without conditioning), 3 were conditioned with 4.5 Mg ha−1 of biosolids on a dry base, and 3 were conditioned with the same amount of compost. The parameters determined for biosolids, compost, and soil were: pH, electrical conductivity (EC), organic matter (OM), total nitrogen, available phosphorus, cation exchange capacity (CEC), exchangeable cations (Ca, Mg, Na and K), total and available heavy metals (Cd, Cr, Cu, Ni and Zn); for the plant: height reached, green seeds productivity and yield per treatment (ton ha−1); for the seeds: humidity, ashes, fiber, fats, protein, starch and total and available heavy metals (Cd, Cr, Cu, Ni and Zn). pH was slightly acid in soil treated with biosolids (6.71). OM and CEC did not represent significant differences. Total concentrations of Cr, Zn, Ni and Cu in soil presented significant differences ( p < 0.05) between treated soil and the control, Cd was not detected. Cu was the most available metal in soil treated with compost (15.31%), Cd and Cr were not detected. The plants had higher growth rates with biosolids (112.22 cm) and compost (103.73 cm); higher green broad bean productivity and higher seed yield, especially in plots containing biosolids, which had rates three times higher than the control. In regards to broad bean seeds, content of ashes, fiber, fats, protein, starch and heavy metals (Cu, Ni and Zn), there were no significant differences between the treatments. Cd and Cr were not detected. In conclusion, it has been proven that the use of biosolids and compost studied in this broad bean crop do not involve an environmental risk, and thus give way to a solution to the problem of final disposition of biosolids in the region. [ABSTRACT FROM AUTHOR]

The assumption of constant local coefficients is one of the first restrictions in most of the smoothing theories for transport in porous media. In this paper we present a formal analysis of the effects produced by nonconstant local transport coefficients on the nonlinear behavior of the effective transport properties. In particular, we use the volume averaging method to study heat transport in a two-component system considering the local thermal conductivities as analytical functions of the temperature. Within this approach we obtain a general expression for the effective nonlinear thermal conductivity dependence on the averaged temperature gradient. The important result is that the effective conductivity is obtained by a linearly bounded problem (the closure problem), just as if the conductivities were constants, by replacing the constant conductivities by the actual temperature dependent ones. As an example, we model the porous medium as cylindrical inclusions in a periodic array and solve the closure problem for the case of the one-equation model. We analyze the values of the second derivative of the thermal conductivity with respect to the temperature to establish the range where the nonlinear corrections must be considered to correctly describe the effective transport. [ABSTRACT FROM AUTHOR]

The purpose of this study was to determine the benefits and costs to community-based primary care physicians teaching medical students in their offices. Survey data were collected from 185 preceptors between 1990 and 1996. Respondents reported increases in their enjoyment of the practice of medicine (82%), time spent reviewing clinical medicine (66%), desire to keep up with recent developments in medicine (49%), and patients' perception of their stature (44%). However, 61% reported a decrease in the number of patients seen when a student was present. We conclude that despite the costs associated with teaching medical students in their offices, preceptors derived many benefits. [ABSTRACT FROM AUTHOR]