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We present a carrier-envelope offset (CEO) stable ytterbium-doped fiber chirped-pulse amplification system employing the technology of coherent beam combining and delivering more than 1 kW of average power at a pulse repetition rate of 80 MHz. The CEO stability of the system is 220 mrad rms, characterized out-of-loop with an f-to-2f interferometer in a frequency offset range of 10 Hz to 20 MHz. The high-power amplification system boosts the average power of the CEO stable oscillator by five orders of magnitude while increasing the phase noise by only 100 mrad. No evidence of CEO noise deterioration due to coherent beam combining is found. Low-frequency CEO fluctuations at the chirped-pulse amplifier are suppressed by a “slow loop” feedback. To the best of our knowledge, this is the first demonstration of a coherently combined laser system delivering an outstanding average power and high CEO stability at the same time.

Exploring the formation of diatomic radicals in femtosecond plasmas is important to establish the most dominant kinetic pathways following ionization and dissociation of small molecules. In this work, cyano radical formation has been studied from bromoform, acetonitrile, and methanol in nitrogen and argon plasmas created with a focused femtosecond laser beam operating at 100 kHz repetition rate and 1030 nm wavelength with 43 fs pulse length and 250 μJ pulse energy. Time-resolved Fourier transform fluorescence spectroscopy was applied in the ultraviolet–visible (UV–vis) spectral range for the characterization of the rotational and vibrational temperatures of the CN(B) radicals via fitting the experimental data. The high repetition rate of the laser allows efficient coupling with the step-scan Fourier transform spectroscopy method. Coulomb explosion at the very high intensity (∼1016W/cm2) resulted in the formation of nascent atoms, ions, and electrons. The condensation reactions of carbon and reactive nitrogen species resulted in the formation of CN(B2Σ+) radicals and C2(d3Πg) dicarbon molecules/radicals. The CN(B) radicals were formed at the highest concentration in the case of bromoform because the weak carbon–bromine bonds resulted in reactive carbon atoms and CH radicals, which are reactive precursors for the CN(B) radical formation. In the case of acetonitrile, immediate production of CN(B) is observed with nanosecond resolution, which suggests that the CN is formed either via photodetachment or via roaming reaction associated with the Coulomb explosion of the parent molecule. The nascent rotational temperature was very high (∼6000–8500 K) and rapidly decreased in all instances within 40 ns with bromoform and acetonitrile. The highest vibrational temperature (∼7800 K) was observed in an acetonitrile/Ar mixture that decreased in about 30 ns and then increased in the observed time window. The vibrational temperature increased in all samples between 30 and 200 ns. The time dependence of fluorescence is described with a monoexponential decay in the case of acetonitrile/Ar and with biexponential decays in all other instances in the 0–250 mbar total pressure range. The shorter time constant is close to the radiative lifetime of CN(B) emission (∼60–80 ns), which can be attributed to the CN(B) radicals produced in the first few collisions at lower pressures. The longer CN(B) emission is from CN(B) created by slower chemical reactions involving carbon atoms, C2radicals, and reactive nitrogen-containing species.

In our experiments we compared the serum lipoprotein lipid composition of Fischer 344 (F344) and Long-Evans (LE) inbred rats as well as of their hybrid FLF1from both sexes after feeding them for 2, 4 and 8 weeks with different diets. The following diets were used: 1) standard diet marked as CRLT/N; 2) diet reach in butter marked as BR; 3) diet containing cholesterol, sodium cholate and methylthiouracil marked as CR; 4) diet marked as BRC, which is the Hartroft-Sós diet modified by our research group consisting of the diets BR and CR. The latter diet was the most effective, because within two weeks the level of serum total cholesterol, LDL-cholesterol, HDL-cholesterol and triglyceride in the F344 female rats increased 8, 30, 4 and 8 times, respectively. The male rats of the Long-Evans strain showed moderately increased values while the FLF1female hybrids derived from the hybridization of LE males and F344 females had values closer to those of the mother strain. Despite the fact that during this time the LDL/HDL ratio increased from 0.06 to 2.97 and the PON-1 activity decreased to one-third, a significant lipid deposition could not be shown in the wall of the abdominal aorta even two months later. Our experimental model is suitable for the chemoprevention of dyslipidaemia or rapid testing of molecules chosen for its treatment.

Background: Altered secretion of adipokines and non-esterified fatty acid (NEFA) seems to play a pivotal role in the abdominal obesity-related insulin resistance (IR). Aim: To determine semi-quantitatively the impact of serum NEFA, interleukin-6 (IL-6), tumor necrosis factor-α (TNF-α), leptin, adiponectin, and resistin levels on IR measured by homeostasis model assessment (HOMA-IR). Material/subjects: Seventy-four Caucasian subjects forming 3 age-, and sex-matched groups were included into the study [Group 1 and 2: non-diabetic obese patients, no.= 25, body mass index (BMI): 28–39.9 kg/m2, no.=25, BMI≥40 kg/m2, respectively, and Group 3: 24 healthy, normal weight control subjects]. Methods: Serum levels of NEFA and adipokines as well as other metabolic variables including HOMA-IR were measured. Results: HOMA-IR was associated positively with BMI, waist circumference, serum NEFA, leptin, IL-6, and TNF-α levels, negatively with adiponectin, with no significant relation to resistin. In multiple regression analyses, of these factors leptin was a strong, IL-6 and adiponectin were weak independent predictors of HOMA-IR, while the others were not significant determinants of HOMA-IR. However, even together, they explained only 35–36% of variance of HOMA-IR. Conclusions: Although IR has associations with many of the investigated parameters, of these, only serum level of leptin, and in lesser degree IL-6 and adiponectin are independent determinants of the severity of IR. Moreover, even together they explain only a minority of variance IR.

SUMMARYObjective:High-density lipoprotein (HDL)-associated paraoxonase (PON) activity may play an important role in the inhibition of low-density lipoprotein (LDL) oxidation. Previous studies have demonstrated that serum PON activity is decreased in patients with hyperlipoproteinaemia and coronary heart disease. The study presented here examined the effect of short-term treatment with simvastatin and atorvastatin on lipids and PON activity in patients with hyperlipoproteinaemia.Research design and methods:A prospective, non-blinded, single-group, cross-over, comparative trial was performed. Following an 8-week dietary run-in period, 49 patients (23 men and 26 women, mean age: 59.8 ± 7.9 years) with Fredrickson type IIa. and IIb. hyperlipoproteinaemias were randomized to receive either simvastatin 20 mg/day or atorvastatin 10 mg/day for 3 months. Following an 8-week washout period, patients were crossed-over to receive the other drug for a further 3 months. Serum lipids were measured and serum PON activity was determined spectrophotometrically using paraoxon as a substrate.Results:Simvastatin treatment significantly reduced serum cholesterol, LDL-cholesterol (LDL-C) and apolipoprotein (apo) B levels ( p< 0.001). Atorvastatin had a more pronounced cholesterol, LDL-C- and apo B-lowering effect ( p< 0.001) compared with simvastatin. Both statins also significantly reduced serum triglyceride levels ( p< 0.01). Simvastatin and atorvastatin caused no significant change in the levels of HDL-cholesterol (HDL-C) and apo A1. HDL-associated PON activity did not change significantly after simvastatin therapy, but significantly increased after atorvastatin treatment ( p< 0.05).Conclusions:Short-term administration of simvastatin did not increase PON activity. Atorvastatin treatment had a favourable effect on lipid profile and increased the activity of HDL-associated PON.

Cytosolic free calcium ([Ca(2+)](i)) is an important second messenger during stimulation in a wide variety of cells, including polymorphonuclear leukocytes (PMNs). Its mobilization in PMNs is altered in various diseases such as atherosclerosis and ageing. In chronic haemodialysis (HD) patients, both atherosclerosis and accelerated ageing are well known. Therefore [Ca(2+)](i) in resting PMNs of HD patients was determined along with certain parameters which might affect it, such as recombinant human erythropoietin (rHuEpo) treatment, calcium-phosphate balance, and biocompatibility of dialysis membranes.

In supply chains of willow (Salix viminalis) biomass to energy plants, drying is advisable in order to enable safe long-term storage, increase boiler efficiency and reduce gaseous emissions. To gain insight into the drying process, drying characteristics of willow chips and stems were investigated experimentally in a drying installation. The drying process was modelled with a diffusion equation. The effective water diffusivity Deffwas assumed to be a simple algebraic function of the dimensionless moisture concentration m:Deff=D0ma, with D0being the initial diffusivity, and aan empirical exponent. Drying of a chip and of a stem without bark could be successfully described with a diffusion equation for a plane sheet and a cylinder, respectively. Drying of a stem with bark could be successfully described as drying of a stem without bark surrounded by a thin layer (bark) with a much lower diffusivity. Compared to a chip, a stem without bark dried approximately 10 times slower from fresh state to equilibrium moisture content, mainly due to the larger diffusion distance of the stem. A stem with bark dried approximately 10 times slower than a stem without bark due to the low diffusivity of the bark.

In the present study the signal transduction of the formyl-Met-Leu-Phe receptor was studied in granulocytes obtained from control subjects and patients with elevated low density lipoprotein levels. According to our results, 10 nm formyl-Met-Leu-Phe in control cells activates phospholipase C inducing a pronounced inositol phosphate production followed by a Ca(2+) signal from intracellular pools. The pertussis toxin-sensitive O(2)(-) generation and leukotriene synthesis were moderate. In contrast, in granulocytes from hypercholesterolemic patients, formyl-Met-Leu-Phe triggered an intensive pertussis toxin-insensitive oxidative burst and leukotriene synthesis. The inositol trisphosphate and Ca(2+) signals were decreased significantly in granulocytes of hypercholesterolemic patients and seem to be dependent on the extracellular Ca(2+) content. Furthermore, in the resting granulocytes of hypercholesterolemic patients the [Ca(2+)]i and the membrane-bound protein kinase C activity were higher than in controls, the time of normalization after the low Ca(2+) signal was delayed, while the membrane fluidity was decreased. Our results suggest that in these ex vivo experiments, the high level of circulating low density lipoprotein in patients can affect the membrane composition of granulocytes leading to altered signal transduction by the formyl-Met-Leu-Phe receptor, to altered Ca(2+) pump-activity, and protein kinase C translocation.

The main functional characteristics of a modular solar dryer are described briefly on the base of the non-equilibrium thermodynamics with emphasis on the possibility of a complete modelling of the plant. A new algorithm based on non-equilibrium thermodynamics principle is proposed for modelling of the crucial simultaneous heat and mass transfer problem in crop layers. An analytical solution is given for the first-order approximation of the relevant coupled transport equations.

The effect of sulindac, a nonsteroidal anti-inflammatory drug, on renal prostaglandin synthesis and renal function variables was investigated in six cirrhotic patients with tense ascites and marked sodium retention. We studied serum thromboxane (TXB2) production, urinary prostaglandin excretion (6-keto-prostaglandin F1 a and TXB2) and renal function before and after administration of a therapeutic dose of sulindac (400 mg). After treatment, no significant changes were observed in urinary prostaglandin excretion, serum creatinine concentration, urine volume, or urinary sodium and creatinine clearance, whereas the serum TXB2 concentration was reduced in 89%. In five patients systemic prostaglandins were inhibited, but renal excretion remained unchallenged. However, one patient showed marked reduction of urinary prostaglandins associated with a depression of renal function. The study suggests that sulindac could be a safe substitute for other nonsteroidal anti-inflammatory drugs in cirrhotic patients with ascites. Further pharmacological trials seem to be warranted.

Steady-state parameters of whole-cell K+current have been determined in human peripheral blood lymphocytes of young (20-50 y.) and elderly (>90 y.) volunteers by patch-clamp. The magnitude and voltage dependence of the K+conductance were similar in both lymphocyte populations. The midpoint of steady-state inactivation was −53.3 ± 2.3 mV for lymphocyte population of young individuals and −65.0 ± 3.0 mV for that of elderly, showing a significant shift to hyperpolarized potentials. The peak of the steady-state open probability of the K+channels was decreased and shifted to depolarized potentials by approx. 12.5 mV for lymphocytes of elderly donors. It is suggested that the observed differences in the K+current parameters may be at least partly responsible for the impaired responsiveness of elderly lymphocytes to proliferative stimuli.

In this paper the main characteristics of a modular solar dryer are described briefly. A detailed calculation of the collector unit is performed in order to obtain the main thermo-hydrodynamical properties of its functioning. It is shown, that the turbulence phenomena must be taken into account and the change of the air pressure is determined along with the turbulent boundary layer theory. A new, general algorithm based on the properties of stratified media is proposed for modelling of the dryer unit.

From perianth of Lilium candidum L. a new flavonoid, lilyn has been isolated by column chromatography and identified by 1H and 13C NMR spectroscopy as 3-O-[β-D-glucopyranosyl (1-2)β-D-galactopyranoside]-kaempferol.