Comprehensive knowledge of hydrodynamics inside the feeding channels of spira-lwound membrane modules is recognized as crucial for the efficient operation of such separation equipments. Slits are laboratory models widely used to mimic the fundamentals of hydrodynamics and mass transfer in spiral-wound membrane modules. In this work micro-PIV was the technique chosen to characterize fully developed laminar flows in a slit for both Newtonian and non-Newtonian fluids. Experiments with water, water-glycerol and water-glycerol-xanthan were carried out at different flow rates, ranging from 4.3. to 25.3 L/h. The ternary mixture water-glycerol-xanthan simulates the non-Newtonian rheological behavior of blood. The other fluids are Newtonian and exhibit different viscosities. The fluids rheology was characterized making recourse to a viscometer. Using micro-PIV, velocity maps at several depths of the channel were obtained. As expected, results showed that the Newtonian fluids flows exhibit parabolic profiles typical of laminar developed flows in slits. On the other hand, slightly flattened profiles characterize the non-Newtonian fluid flows. Comparisons with the analytical solutions for laminar developed flows in rectangular slits are very encouraging. and Obsahuje seznam literatury
The objective of this study was to assess a possible link between microalbuminuria (MA), a major ri sk factor of the cardiorenal syndrome and the brain natriuretic peptide (BNP), a marker of cardiac hypertrophy. Two kidney-one clip (2K-1C) renovascular hypertension was induced in 24 male Wistar rats (weighing 220-250 g). Rats were randomized into four groups for 8 weeks: Sham, not treated; Bos, treated with bosentan; Cap, treated with captopril; Bos/Cap, treated with both drugs. Blood pressure, plasma BNP and transforming growth factor β1 (TGF-β1) concentrations, microalbuminuria and creatininemia as well as cardiac mass, BNP, α- and β-myosin heavy chain (MHC) gene expression and kidney histology were determined. Following stenosis, Sham rats developed hypertension (p<0.001), an increase in BNP (p<0.05) and TGF-β1 (p<0.005) concentrations, creatinine levels (p<0.001), and urinary albumin (p<0.001). Under drug treatment, decreases in blood pressure (p<0.001), creatinine levels (p<0.05), plasma TGF-β1 (p<0.005) and BNP (p<0.05) concentrations, were co ncomitant with the absence of MA which was significantly correlated with reductions in cardiac mass (p<0.05) and hypertrophy markers (BNP and β-MHC gene expression) (p<0.005) as well as in renal fibrosis. These findings suggest a potential link between microalbuminuria evolution and BNP as well as a possible effect of microalbuminuria-lowering therapy on halting the progression, or even inducing the regression of cardiac hypertrophy., Y. Saliba, E. Chouery, A. Mégarbané, H. Jabbour, N. Farès., and Obsahuje bibliografii
The microcirculation, like all physiological systems undergoes modifications during the course of pregnancy. These changes aid the adaption to the new anatomical and physiological environment of pregnancy and ensure adequate oxygen supply to the fetus. Even though the microcirculation is believed to be involved in major pregnancy related pathologies, it remains poorly understood. The availability of safe and non-interventional technologies enabling scientists to study the intact microcirculation of the pregnant patient will hopefully expand our understanding. In this article we review the physiological changes occurring in the microcirculation during pregnancy and the role of the microcirculation in gestational related pathologies. We will also describe the available techniques for the measurement and evaluation of the microcirculation. Lastly we will highlight the possible fields in which these techniques could be utilized to help provide a clearer view of the microcirculation in the pregnant woman., I. Abdo, R. B. George, M. Farrag, V. Cerny, C. Lehmann., and Obsahuje bibliografii
Using some observational evidences of filament disturbances associated with microflares we point out the following results:
1. The filament destabilization begins at one of its footpoint,
2. Glose to this footpoint one of two pores are observed, they move with an anomalous velocity as seen in white light pictures.
3. Bríghtenings in Hα and in C IV overlie the location of the pores. The pores may be the signature of new emerging flux.
4. The dynamics observed in Hα filament is generally associated with heating of the filament transitíon zone.
5. The excess energy is released at different places along the filament, but this process does not seem to imply a heating conduction front.
Xenomas caused by Microgemma vivaresi Canning, Feist, Longshaw, Okamura, Anderson, Tsuey Tse et Curry, 2005 were found in liver and skeletal muscle of sea scorpions, Taurulus bubalis (Euphrasen). All muscle xenomas examined were in an advanced stage of destruction. In developing xenomas found in liver, parasites were restricted to the centre of the cell, separated from a parasite-free zone by a nuclear network formed by branching of the host cell nucleus. Although xenomas were able to reach a size of several hundred microns, the surface remained a simple plasma membrane. Host reactions took the form of penetration by phagocytes and isolation by fibroblasts. Once the xenoma had been attacked, the nuclear profiles became pycnotic and the barrier between parasitized and parasite-free zones was lost. Parasite antigens cannot be exposed at the surface of intact xenomas, as the host does not recognise the enlarging cell as foreign. Breaches in the plasma membrane of the xenoma and leakage of parasite antigens are thought to be the stimuli for phagocyte entry into the cell, its isolation by fibroblasts and eventual granuloma formation.
Microhabitat preference of the monogenean Discocotyle sagittata (Leuckart, 1842) was determined in late spring and late autumn in rainbow trout, Oncorhynchus mykiss (Walbaum), reared in the Isle of Man, UK. Discocotyle sagittata exhibits a preference for attachment to anterior gill arches: 29% of all worms occurred on gill arch I, 28% on II, 25% on III and 18% on IV. This distribution pattern on the introduced salmonid species is the same as reported for its native European host, the brown trout Salmo trutta (L.). Previous experimental work suggested that invasion is a passive process followed by post-invasion migration to anterior gill arches; the present work provides evidence of equivalent site selection taking place in fishes maintained under conditions promoting continuous reinfection in aquaculture. Migration may be density-dependent, since a significant inverse association was found between the intensity of mature parasites and their proportion on anteriormost gill arch I.
Salusin-β is newly identified bioactive peptide of 20 amino acids, which is widely distributed in hematopoietic system, endocrine system, and the central nervous system (CNS). Although salusin- β extensively expressed in the CNS, the central cardiovascular functions of salusin-β are unclear. Our main objective was to determine the cardiovascular effect of microinjection of salusin-β into the nucleus tractus solitarii (NTS) in anesthetized rats. Bilateral or unilateral microinjection of salusin-β (0.94-94 μg/rat) into the NTS dose-dependently decreased blood pressure and heart rate. Bilateral NTS microinjection of salusin-β (9.4 μg/rat) did not alter baroreflex sensitivity. Prior application of the glutamate receptor antagonist kynurenic acid (0.19 μg/rat, n=9) into the NTS did not alter the salusin-β (9.4 μg/rat) induced hypotension and bradycardia. However, pretreatment with the GABA receptor agonist muscimol (0.5 ng/rat) within the rostral ventrolateral medulla (RVLM) completely abolished the hypotension (-14±5 vs. -3±5 mm Hg, P <0.05) and bradycardia (-22±6 vs. -6±5 bpm, P <0.05) evoked by intra-NTS salusin-β (9.4 μg/rat). In addition, we found that vagotomy didn’t influence the actions of salusin-β (9.4 μg/rat) in the NTS. In conclusion, our present study shows that microinjection of salusin-β into the NTS significantly produces hypotension and bradycardia, presumably by suppressing the activities of presympathetic neurons in the RVLM., Y. Lu, Y. S. Wu, D. S. Chen, M. M. Wang, W. Z. Wang, W. J. Yuan., and Obsahuje bibliografii
This paper ceals with a newly developed electronic system used in the INTERKOSMOS satellite tracking stations. The system consists
o microprocessor nbased single board microcomputer, laser clock board with 100ns accuracy and extermal synchronization logic, time gate board (full programable - delay 100ns to 1s, gate 100ns to 1ms. both with steps 100ns) with laser trigger logic and two communication boards. The system is very flexible by means of software. It may be used in the first generation laser radar (like in Vietnam station) or the second generation with reprate 10 Hz.
Parenteral nutrition-associated liver disease (PNALD) is a severe
complication in patients completely dependent on parenteral
nutrition (PN). The gold diagnostic standard, liver biopsy, is
associated with significant health risk and therefore its use is
limited. MicroRNAs (miRNAs) are small non-coding regulatory
RNA molecules with highly tissue-specific expression and the
secreted miRNAs may serve as non-invasive diagnostic
biomarkers. The aim of this study was to evaluate the expression
of a panel of specific miRNAs associated with liver diseases of
different origin in PN-dependent adult patients in order to design
miRNA panel enabling to precise monitoring of PNALD
progression. Twelve PN-dependent patients with short bowel
syndrome (SBS) were monitored on three/four-month basis for
up to 24 months. Forty-five age- and sex-matched subjects
without any known liver pathology served as controls. Specific
miRNAs expression was determined by RT-qPCR using TaqMan
probes (Thermofisher). Liver function test parameters were
determined in certified clinical laboratories. Six of the tested
miRNAs exhibited significantly altered expression compared with
healthy controls, three of them (MIR122, MIR1273g, and
MIR500a) were upregulated while three were down-regulated
(MIR505, MIR199a, MIR139). MIR122 positively correlated with
serum AST and ALT activities while MIR1273g positively
correlated with serum CRP concentration and GGT activity.
MIR505, MIR199a, and MIR139 negatively correlated with serum
GGT activity. Fluctuation of these parameters well paralleled
serum miRNA concentrations in all patients throughout the whole
observation period. We identified six miRNAs whose serum
concentrations are significantly altered in PN-dependent patients
with PNALD and correlate with markers of inflammation,
cholestasis or hepatic injury. Their reliability as markers of PNALD
progression needs to be further evaluated.
Marssoniella elegans Lemmermann, 1900, a parasite of ovarial tissues of the copepod Cyclops vicinus Uljanin, 1875, was studied as a representative of aquatic-clade microsporidia which form ''heteroinfectious spores'' (spores not infective to the original host as opposed to ''homoinfectious spores'' which are infective for the original host) and which thus should require an alternate host. Several structural characters of this microsporidian are similar to those of copepod morphs of microsporidia infecting mosquitoes. However, small subunit ribosomal DNA phylogeny indicates that caddis flies (Insecta, Trichoptera) might be the alternate hosts of Marssoniella. Ultrastructural data obtained are used to redefine the genus Marssoniella Lemmermann, 1900 and its type species Marssoniella elegans.