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We report on the use of the Z-scan technique with a beam composed with two modes to probe the nonlinear optical properties of phosphate glasses doped with Er^3+−Yr^3+ and silver nanoparticles. Understanding the linear and nonlinear properties of these materials is crucial to evaluate whether they are candidates to be used as gain media in lasers or optical amplifiers. Experiments are carried out by implementing the open-aperture Z-scan technique with bimodal laser pumping (LG_00 and LG_20) at 908.6 nm. The analysis is performed using a simplified model that incorporates nonlinear absorption and saturation intensity of the samples. The advantage of using a beam with a bimodal structure is that it allows us to evaluate the energy transfer between the modes, which is relevant, since the optical active media act as an intermediary. This process is incorporated through an effective phenomenological parameter in the model that we use in our analysis.

The objective of this review was to systematically evaluate the available clinical evidence for the prescription of strength training and cardiovascular endurance exercise programs for pediatric and adult burn survivors so that practice guidelines could be proposed. This review provides evidence-based recommendations specifically for rehabilitation professionals who are responsible for burn survivor rehabilitation. Summary recommendations were made after the literature was retrieved by systematic review, was critically appraised by multiple authors and the level of evidence determined in accordance with the Oxford Centre for Evidence-based Medicine criteria.1Although gaps in the literature persist and should be addressed in future research projects, currently, strong research evidence supports the prescription of strength training and aerobic conditioning exercise programs for both adult and pediatric burn survivors when in the presence of strength limitations and/or decreased cardiovascular endurance after evaluation.

We reported Supercontinuum (SC) generation in standard telecom fiber using picosecond pulses of microchip laser. The pulses width is 700 ps at 1064 nm, using 57 m long of standard fiber, and the spectra extend from 700 to above 1700 nm, some 100 nm further into the visible. The physical processes leading to the formation of the continuum spectrum were studied by monitoring the growth of the SC while increasing the input power. The coupling efficiency of ours experimental setup between the microchip laser and the telecom fiber helped us to obtain this wide spectrum.

Supercontinuum generation is being widely studied due to its applications in communications, medicine and metrology. Usually, special fibers, such as photonic crystal fibers and dispersion-shifted fiber, have been utilized. However, there is few information about the potential use of standard fiber with this purpose, which shows some advantages: low cost and availability. In this work, the influence of losses due to induced macrobends on the supercontinuum generation using standard fiber was studied. The losses were introduced by wrapping 30 m in length of standard fiber on cylinders with different diameter, a nanosecond microchip laser and 1064 nm of wavelength were employed. The continuum was recorded at the fiber output by using an optical spectrum analyzer and its dynamics was analyzed by tuning the launched power. In a first stage, the fiber was used without bends generating strong firs-order Raman Stokes and a supercontinuum spectrum of 636 nm. When the fiber was wrapped in a cylinder of 0.9 cm of diameter to induce macrobends, the Raman Stokes of high order were attenuated and the output spectrum was reduced to 240 nm. Also, a peak pulse was observed, around 1030 nm, that means new frequencies were generated in the near infrared region. Thus, induced macrobends affect the supercontinuum broadening.

In the paper, we investigated the bistable properties of the wideband optical filter on the basis of nonlinear 2D photonic crystal. All-optical flip-flop phenomena have been discovered in such filters which allows switching with ultra-short pulses. Particularly, the attention in this work is paid to the filter characteristics stability as respect to radiation parameters variation as well as to production defects.

Drug resistance is a worldwide problem affecting all pathogens. The human fungal pathogen Aspergillus fumigatuscoexists in the environment with other fungi targeted by crop protection compounds, being unintentionally exposed to the selective pressure of multiple antifungal classes and leading to the selection of resistant strains. A. fumigatusazole-resistant isolates are emerging in both clinical and environmental settings.

Cyclosporin A pharmacokinetics were studied following intravenous and abomasal dosing in an open, crossover study in healthy, merino ewes. Five different doses of cyclosporin A were dispersed in milk and administered into the abomasum through a surgically inserted fistula which simulates oral administration. Cyclosporin A was well tolerated. Whole blood concentrations of cyclosporin A were measured by HPLC and mean clearance (0·45 ± 0·05 L h−1kg−1), distribution volume (4·4 ± 2·0 L kg−1), mean residence time (9·6 ± 4·1 h) and half-life (12·1 ± 3·1 h) were calculated. Negligible cyclosporin A was excreted in urine or bile. Area under the curve increased proportionally with doses up to 26·3 mg kg−1, but was curvilinear above this dose. Abomasal bioavailability at 6·4 mg kg−1was 0·26 ± 0·09, and mean absorption time was 4·7 ± 11·1 h. Considerable pharmacokinetic variability was observed, particularly after abomasal administration. Cyclosporin A pharmacokinetics in sheep lie within the values reported in man after renal, bone marrow and cardiac transplantation.

Experimental observations of 1D and 2D self-focusing in a BaTiO3 crystal under externally DC applied electric field are reported. Stationary self-focusing behaviour can be obtained with and without additional uniform illumination.

The total vapor pressure of liquid mixtures of xenon and cyclopropane has been measured at 161.39 K (the triple-point of xenon) and at 182.33 K (the triple-point of dinitrogen oxide), as a function of composition. At 182.33 K the liquid densities were also measured. The mixtures show positive deviations from Raoult's law. Both the excess molar Gibbs energy (%@mt;sys@%%@ital@%G%@rsf@%%@sx@%%@ital@%m%@rsf@%%@be@%E%@sxx@%%@mx@% ) and the excess molar volume (%@mt;sys@%%@ital@%V%@rsf@%%@sx@%%@ital@%m%@rsf@%%@be@%E%@sxx@%%@mx@% ) were calculated from the experimental data. For the equimolar mixture, %@mt;sys@%%@ital@%G%@rsf@%%@sx@%%@ital@%m%@rsf@%%@be@%E%@sxx@%%@mx@% = 90.6 J mol^-1 at 161.39 K, %@mt;sys@%%@ital@%G%@rsf@%%@sx@%%@ital@%m%@rsf@%%@be@%E%@sxx@%%@mx@% = 124.1 J mol^-1 at 182.33 K, and %@mt;sys@%%@ital@%V%@rsf@%%@sx@%%@ital@%m%@rsf@%%@be@%E%@sxx@%%@mx@% = −0.758 cm³ mol^-1 at 182.33 K. The excess molar enthalpy (%@mt;sys@%%@ital@%H%@rsf@%%@sx@%%@ital@%m%@rsf@%%@be@%E%@sxx@%%@mx@% ) could be estimated from the temperature dependence of %@mt;sys@%%@ital@%G%@rsf@%%@sx@%%@ital@%m%@rsf@%%@be@%E%@sxx@%%@mx@% and found to be −168 J mol^-1. The results were interpreted using the 1cLJ perturbation theory of Fisher et al.

The formation constants of the fluoroquinolones norfloxacin and ciprofloxacin with Mg2+(log β1=2.97(4), log β2=5.6(2)), Zn2+(log β1=3.77(2), log β2=7.59(3)), and Fe2+(log β1=3.99(5), log β2=7.2(5)) were determined by potentiometric titration. The pH at which precipitation occurred in the titration solutions was compared for the metal ions Ca2+, Mg2+, Zn2+, Fe2+, Cu2+, and Al3+. The formation constants were used to predict a rank order of metals that may be expected to hinder the gastrointestinal absorption of the fluoroquinolones, in vivo. The effects of metal ions on the pharmacokinetics of orally-administered norfloxacin in the dog were investigated. Norfloxacin (12mg/kg) was administered alone or with equimolar doses of each of the chloride salts of Ca2+, Mg2+, Zn2+, Fe2+, and Al3+. Statistically significant reductions in serum norfloxacin concentrations were observed after analysis by HPLC. The Cmaxwas reduced 29–85%, while the area under the norfloxacin serum concentration–time curve (AUC0–∞) was reduced by 29–79%. The extent of the reduction in AUC0–∞was correlated with the magnitude of the formation constant of the 1:1 norfloxacin:metal chelate complex for the divalent metal ions. On coadministration of 12mg/kg norfloxacin with various doses of Mg2+and (chloride) the AUC0–∞and Cmaxdecreased with increasing Mg2+dose. The interaction peaked at a Mg2+:norfloxacin ratio of 1:2, suggesting the formation of a 1:2 Mg:norfloxacin complex. Formation constant data were used to simulate the percentage of norfloxacin complexed at pH 6.5. Combinations of metal ion and norfloxacin which result in only a small extent (<20%) of norfloxacin complex formation can result in relatively large decreases in oral bioavailability of this antimicrobial agent.

We compare the electric and pure magnetic contributions to the differential cross sectionds(np?np?)/ds' of neutron-proton bremsstrahlung. We conclude that the pure magnetic contribution cannot explain the discrepancy between the theoretical and experimental results as found by Dupont et al.

Porphyria cutanea tarda (PCT) is common and usually associated with HCV chronic infection and HFE polymorphisms. Since DAA IFN-free regimens availability, SVR for HCV is nearly a constant and we wonder whether HCV SVR determine PCT evolution.

An experimental study of the effects of an auxiliary 976 nm pump signal on the four-wave mixing parametric bands generated with a 1064 nm pump in a normal dispersion Er-doped photonic crystal fiber is presented. The four-wave mixing signal and idler bands shift to shorter and longer wavelengths, respectively, with increasing 976 nm pump power. It is shown that the wavelength-dependent resonant refractive index change in the erbium-doped core under 976 nm pumping is at the origin of the effect.

The interplay between chromatic dispersion and nonlinear effects is patent. Once a photonic crystal fiber (PCF) preform has been prepared, changing the parameters that control the fabrication process it is possible to adjust the dispersion properties of the fiber. In addition, it is very useful to develop postprocessing techniques that enable a fine adjustment of the dispersion along a section of PCF. The tapering of PCF, using a fusion and pulling technique, has been established as a rather useful technique to engineer the dispersion properties along tens of centimeters. Some of our recent experiments demonstrate that the use of erbium doped PCF enables an optical control of the dispersion through optical pumping of the rare earth ions. Our interest is focused on the exploitation of nonlinear PCF for the development of fiber light sources. Thus, we will present several experiments on supercontinuum and photon pairs generation, through degenerated four-wave mixing (FWM), in order to illustrate the control that one can achieve on the optical spectra of these light sources as a function of different dispersion control approaches.

The present study was designed to evaluate the influence of two haemodialysis membranes of different biocompatibility on red blood cell function. Twelve patients were studied in two consecutive dialyses, with cuprophan and cellulose acetate. Blood was extracted at 0, 20 and 180 min after the beginning of the haemodialysis session and general haematological parameters, osmotic fragility, deformability, methaemoglobin concentration and malonyldialdehyde (MDA) red blood cell content were determined. Osmotic fragility improved with both membranes, but this improvement was more marked with cellulose acetate. MDA red blood cell content showed a tendency to increase after 3h with cuprophan (114±11% of the basal value), whereas it tended to decrease with cellulose acetate (92±12%), the differences between the two groups being statistically significant. These results suggest that red cell function may improve by changing the characteristics of haemodialysis membranes. This phenomenon could be related to a better biocompatibility.