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Detailed morphometric data concentrating on the development of primary ossification centers in human fetuses is critical for the early detection of developmental defects. Thus, an understanding of the growth and development of the parietal bone is crucial in assessing both the normal and pathological development of the calvaria. The size of the parietal primary ossification center in 37 spontaneously aborted human fetuses of both sexes (16 males and 21 females) aged 18-30 weeks was studied by means of CT, digital-image analysis and statistics. The numerical data of the parietal primary ossification center in the human fetus displays neither sex nor laterality differences. With relation to fetal age in weeks, the parietal primary ossification center grew in sagittal diameter according to the quadratic function y = 16.322 + 0.0347 × (age)² ± 1.323 R² = 0.96, in projection surface area according to the cubic function y = 284.1895 + 0.051 × (age)³ ± 0.490, while in both coronal diameter and volume according to the quartic functions: y = 21.746 + 0.000025 × (age)⁴ ± 1.256 and y = 296.984 + 0.001 × (age)⁴, respectively. The obtained morphometric data of the parietal primary ossification center may be considered age-specific references, and so may contribute to the estimation of gestational ages and be useful in the diagnostics of congenital cranial defects.

Summary: In this work, the author refers to the own research entitled ''Citizens' participation in the creation and implementation of public policy. Electoral participation''. The aim of this study was to analyze factors affecting civic participation in the form of participation in general elections. The study gave a reason to look more deeply into the formation of a pluralistic society in the age of climate change and social unrest. In this article, however, the author analyzes the impact of climate change in the process of creating a pluralistic society. The focal point of the paper has to do with the implementation of the Lifelong Learning concept in contemporary society. The aim of this work is to indicate the public authority the need for the more effective methods of activating and educating our society in the fight against climate change.

Functional decomposition might be used during logic synthesis, machine learning, data mining and other domains. Decomposition of binary functions is widely used during LUT-based FPGA technology mapping. However, the range of applications of functional decomposition might be wider when multiple-valued functions are considered. In this paper, DECOLib: a Java library for functional decompositions of discrete functions is presented. The library is based on blanket algebra and provides data structures and functions, which allow building the decomposition algorithms for binary/multiple-valued functions. Examples demonstrating applications of these algorithms, as well as suggestions for further research directions, are also presented.

The paper presents the BMB methodology for synthesis of binary functions, which can be applied to synthesis of functions implemented in LUT-based FPGAs. The BMB synthesis uses the functional decomposition based on symbolic decomposition and symbolic encoding. The methodology uses two optimization methods. First, the symbolic decomposition is used to build the multiple-valued network of functions. Second, the symbolic encoding is used to find an encoding that simplifies the decomposition. The symbolic optimization overpasses limits of the existing decomposition methods, where optimal encoding for LUT-based implementations is not possible. Simultaneously, the method can be used in the synthesis of high-level architecture where dependencies can be described using symbolic values. Experimental results showed that the presented methodology allows significant reduction of the cost of the FPGA implementation.

The Polish Fireball Network (PFN) is a project to monitor regularly the sky over Poland in order to detect bright fireballs. In 2016 the PFN consisted of 36 continuously active stations with 57 sensitive analogue video cameras and 7 high resolution digital cameras. In our observations we also use spectroscopic and radio techniques. A PyFN software package for trajectory and orbit determination was developed. The PFN project is an example of successful participation of amateur astronomers who can provide valuable scientific data. The network is coordinated by astronomers from Copernicus Astronomical Centre in Warsaw, Poland. In 2011–2015 the PFN cameras recorded 214,936 meteor events. Using the PFN data and the UFOOrbit software 34,609 trajectories and orbits were calculated. In the following years we are planning intensive modernization of the PFN network including installation of dozens of new digital cameras.

The commonly used flax process of decortication allows the mechanical extraction of fibre from plant stems without prior retting. The one-type fibre obtained in this process is characterised by very low quality, as it is poorly divided, has high linear mass and high amounts of impurities. This paper presents a description of a newly developed method of obtaining high quality flax cottonized fibre from low quality decorticated fibre by application of a wet degumming process for fibre. The experiment involved studying the parameters of flax fibres after each step of the technological process i.e. after decortication, wet degumming and final mechanical cottonisation. The study covered tests of the following fiber parameters: linear mass, length, impurities, chemical composition as well as thermogravimetric analysis, Fourier transform infrared spectroscopy analysis and scanning electron microscopy images. The results confirm the efficiency of the method applied for obtaining high quality fibre from decorticated flax fibre.

The paper presents an analysis of Polish Fireball Network (PFN) observations of enhanced activity of the Southern Taurid meteor shower in 2005 and 2015. In 2005, between October 20 and November 10, seven stations of PFN determined 107 accurate orbits with 37 of them belonging to the Southern Taurid shower. In the same period of 2015, 25 stations of PFN recorded 719 accurate orbits with 215 orbits of the Southern Taurids. Both maxima were rich in fireballs which accounted to 17% of all observed Taurids. The whole sample of Taurid fireballs is quite uniform in the sense of starting and terminal heights of the trajectory. On the other hand a clear decreasing trend in geocentric velocity with increasing solar longitude was observed. Orbital parameters of observed Southern Taurids were compared to orbital elements of Near Earth Objects (NEO) from the NEODYS-2 database. Using the Drummond criterion $D'$ with threshold as low as 0.06, we found over 100 fireballs strikingly similar to the orbit of asteroid 2015 TX24. Several dozens of Southern Taurids have orbits similar to three other asteroids, namely: 2005 TF50, 2005 UR and 2010 TU149. All mentioned NEOs have orbital periods very close to the 7:2 resonance with Jupiter's orbit. It confirms a theory of a "resonant meteoroid swarm" within the Taurid complex that predicts that in specific years, the Earth is hit by a greater number of meteoroids capable of producing fireballs., 13 pages, 10 figures, accepted for publication in MNRAS

On the night of Oct 31, 2015 two bright Southern Taurid fireballs occurred over Poland, being one of the most spectacular bolides of this shower in recent years. The first fireball - PF311015a Okonek - was detected by six video stations of Polish Fireball Network (PFN) and photographed by several bystanders, allowing for precise determination of the trajectory and orbit of the event. The PF311015a Okonek entered Earth's atmosphere with the velocity of 33.2 +\- 0.1 km/s and started to shine at height of 117.88 +\- 0.05 km. The maximum brightness of -16.0 +\- 0.4 mag was reached at height of 82.5 +\- 0.1 km. The trajectory of the fireball ended at height of 60.2 +\- 0.2 km with terminal velocity of 30.2 +\- 1.0 km/s. The second fireball - PF311015b Ostrowite - was detected by six video stations of PFN. It started with velocity of 33.2 +\- 0.1 km/s at height of 108.05 +\- 0.02 km. The peak brightness of -14.8 +\- 0.5 mag was recorded at height of 82.2 +\- 0.1 km. The terminal velocity was 31.8 +\- 0.5 km/s and was observed at height of 57.86 +\- 0.03 km. The orbits of both fireballs are similar not only to orbits of Southern Taurids and comet 2P/Encke, but even closer resemblance was noticed for orbits of 2005 UR and 2005 TF50 asteroids. Especially the former object is interesting because of its close flyby during spectacular Taurid maximum in 2005. We carried out a further search to investigate the possible genetic relationship of Okonek and Ostrowite fireballs with both asteroids, that are considered to be associated with Taurid complex. Although, we could not have confirmed unequivocally the relation between fireballs and these objects, we showed that both asteroids could be associated, having the same origin in a disruption process that separates them., Comment: 12 pages, 10 figures, accepted for publication in MNRAS

Multivalued logical network consists of modules connected by multivalued signals. During synthesis each module is decomposed into smaller ones using the symbolic decomposition. Since the efficiency of the decomposition strongly depends on encoding of multivalued signals, the result of synthesis depends on the order, in which the consecutive modules are implemented. This paper presents the method of FPGA-oriented synthesis of multivalued logical networks. Experimental results showed that our approach significantly reduces the cost of implementation.

Context. We report an analysis of photometric behaviour of DI UMa, an extremely active dwarf nova. The observational campaign (completed in 2007) covers five superoutbursts and four normal outbursts.Aims. We examined principal parameters of the system to understand peculiarities of DI UMa, and other active cataclysmic variables.Methods. Based on precise photometric measurements, temporal light curve behaviour, $\rm O{-}C$ analysis, and power spectrum analysis, we investigated physical parameters of the system.Results. We found that the period of the supercycle now equals $31.45 \pm 0.3$ days. Observations during superoutbursts infer that the period of superhumps equals $P_{\rm sh} = 0.055318(11)$ days ($79.66\pm 0.02$ min). During quiescence, the light curve reveals a modulation of period $P_{\rm orb} = 0.054579(6)$ days ($78.59 \pm 0.01$ min), which we interpret as the orbital period of the binary system. The values obtained allowed us to determine a fractional period excess of $1.35\% \pm 0.02\%$, which is surprisingly small compared to the usual value for dwarf novae (2%–5%). A detailed $\rm O{-}C$ analysis was performed for two superoutbursts with the most comprehensive coverage. In both cases, we detected an increase in the superhump period with a mean rate of $\dot P/P_{\rm sh} = 4.4(1.0)\times 10^{-5}$.Conclusions. Based on these measurements, we confirm that DI UMa is probably a period bouncer, an old system that reached its period minimum a long time ago, has a secondary that became a degenerate brown dwarf, the entire system evolving now toward longer periods. DI UMa is an extremely interesting object because we know only one more active ER UMa star with similar characteristics (IX Dra).

Solubility of water and association of selected surfactants in gasoline modified with hydrophilic modifiers was studied. The solubility of water can also be modified by the presence of amphiphilic substances which, also when present in negligible amounts, can promote the association phenomena with the formation of reversed micelles. The cores of such micelles containing hydrophilic groups located inside the micelle can contain water pools, enhancing in this way the solubility of water and improving some properties for which an aqueous environment is needed. The aim of this work was to study the effect of some hydrophilic additives (alcohols and t-butylmethyl ether) and some selected surfactants (sodium bis-(2-ethylhexyl)sulfosuccinate, calcium dodecylbenzenesulfonate and branched alkylamines) upon the solubility of water in modified gasoline, interfacial tension isotherms at modified/water interfaces.

A bright fireball of −10.5 absolute magnitude was observed over Poland on 2005 April 3 at 21:04:41 UTC. It was recorded by two photographic and three video stations of Polish Fireball Network (PFN). A description, atmospheric trajectory, fragmentation details, velocity evolution and orbital data for the meteor are presented.

We report on extensive photometry of the dwarf nova SS Ursae Minoris throughout nine months of 2004. In total, we recorded two superoutbursts and 11 normal outbursts of the star. SS UMi has been known to show frequent superoutbursts with a mean interval of 84.7 days. Our data suggest that the interval between successive superoutbursts lengthened to 197 days, indicating that SS UMi entered a period of untypical behavior manifested by a growth in the quiescent magnitude of the star and a series of frequent, low-amplitude, normal outbursts observed from July to September 2004. The mean superhump period derived for the April 2004 superoutburst of SS UMi is $P_{\rm sh} = 0.070149(16)$ days ($101.015\pm0.023$ min). Combining this value with an earlier orbital period determination, we were able to derive the period excess, which is equal to $3.5\pm1.6$%, and estimate the mass ratio of the binary system as equal to $q=0.16\pm0.07$. During the entire superoutburst, the period decreased at a rate of $\dot P/P_{\rm sh} = -6.3(1.4) \times 10^{-5}$. However, detailed analysis of the timings of superhump maxima seem to suggest a more complex period change, with a decrease in the period during the first and last stages of the superoutburst but an increase in the middle interval.

A theoretical solution to the elastohydrodynamic (EHD) lubrication problem in sliding contacts, which takes into consideration the effect of the change in shape of the gap due to wear on the load-carrying capacity, is presented. The model of such a contact is based on assumptions of Grubin and Ertel (von Mohrenstein). The resultant dimensionless Reynolds and film profile equations have been solved numerically for a number of cases with several values of thickness of the worn layer. Iteration of the EHD film thickness is performed by means of the secant method. Values of the calculated dimensionless film thickness are presented as a function of dimensionless wear. The conclusions concern the influence of the linear wear on the film thickness in heavily loaded sliding contacts. Copyright © 2006 John Wiley & Sons, Ltd.

The single-impurity specific heat c i ( T ) and impurity susceptibility χ i ( T ) of an extended s–d Hamiltonian H are derived and examined in the vicinity of the transition temperature T c . c i ( T ) is found by exploiting the single-impurity solution of H due to Andrei et al., whereas χ i ( T ) by applying second-order perturbation theory for the free energy.

The adsorption and oxidation of ammonia over carbons differing in the chemical structure of surface functional groups have been investigated by FTIR spectroscopy. The reactions of NH3 with carbons have been studied both in the presence and in the absence of oxygen. As a result of NH3 chemisorption, in addition to ammonium salts, there are formed surface amide and imide structures. At the higher temperature surface isocyanate species are formed. Thermal stabilities of surface structures, formed as a result of NH3 chemisorption have been determined by means of FTIR spectroscopy. The activity and selectivity of carbons for the selective catalytic oxidation (SCO) of NH3 to N2 with excess O2 has been shown by microreactor studies at 295–623 K. Carbon catalysts are very active for NH3 oxidation. Nitrogen is generally the predominant product of ammonia oxidation. The selectivity to N2, N2O and NO is determined by the surface oxygen coverage and reaction temperature. The data obtained indicate that the N2 is formed via selective catalytic reduction (SCR) between NHx surface species and NO formed from NH4+ oxidation. This implies that ammonia is activated in the form of NH4+ species for both SCR and SCO processes.

The influence of metal (Pt, Ni) loading and the nature of the active surface of carbon-supported metal catalysts on the reaction of ammonia oxidation have been investigated to understand the high N 2 selectivity of some catalysts. The comparison of the activities of catalysts has shown that NH 3 is converted into N 2 , N 2 O and NO. For all examined catalysts, the N 2 selectivity depends on the temperature of the reaction. Parallel in situ investigations reveal the presence of intermediate surface species. The NH 3 chemisorption on the oxidized carbon sample leads to the formation of the bands attributed to ammonium salts of carboxylic acids. Their rearrangement causes the formation of amide and imide structures. With the rise of the reaction temperature the bands, attributed to –CN at 2158 cm −1 and –NCO at 2220 cm −1 appear.

We have constructed an artificial meteor database resembling in all details the real sample collected by the observers of the Comets and Meteors Workshop in the years 1996-1999. The artificial database includes the sporadic meteors and also events from the following showers: Perseids, Aquarid complex, Alpha Capricornids, July Pegasids and Sagittarids. This database was searched for the presence of the radiants of two weak showers: Alpha Cygnids and Delphinids. The lack of these radiants in the artificial database and their existence in the real observations suggests that Alpha Cygnids and Delphinids are the real showers and their radiants could not be formed as an effect of intersections of back prolongated paths of meteors belonging to other showers., accepted for publication in A&A, 15 pages

An anisotropic generalization of the reduced s–d model with antiferromagnetically coupled impurities is proposed. This extension consists in introducing different coupling constants of s–d interaction and interimpurity coupling for spin components along the c-axis and perpendicular to the c-axis. It is shown that the Hamiltonian of the anisotropic version of the reduced s–d model (AERs–dM), constructed in this manner, is equivalent in the thermodynamic limit to the corresponding mean-field Hamiltonian. Equations for the mean-field parameters are derived. The discussion of the possible solutions of these equations is carried out. The predictions of the AERs–dM are compared with experimental data for magnetization of uranium Kondo compounds UAsS, UAsSe, as function of external magnetic field and temperature. Appropriate adjustment of the parameters of the model allows the theory to reproduce basic features of the substances discussed, viz., c-axis oriented spontaneous magnetization of the system which does not change significantly even in strong external magnetic field perpendicular to this axis.

The RKKY perturbation scheme for the spin 12 s–d exchange model is reexamined in the case of a finite number of electrons per impurity. The distribution of impurities is assumed to be random. The free electron gas representing the unperturbed system in the RKKY approach is replaced by a mean-field system hr asymptotically equivalent to the reduced s–d model Hr which includes part of the s–d exchange. Below the transition temperature Tc of hr the lowest energy levels of the s–d exchange Hamiltonian HK resulting from second-order perturbation theory prove to be ordered in the same manner as those of hr in the limit of weak s–d exchange, favouring the same definite parallel alignment of any pair of impurity spins. It follows therefore that in the low temperature, weak coupling regime, the s–d model exhibits ferromagnetic ordering of impurities. At temperatures above Tc there is no ordering and impurity–impurity exchange has the RKKY form. These observations are consistent with the presence of a low-temperature ferromagnetic phase in numerous compounds with s–d exchange interaction.

This paper describes some results of evaluating the influence of contact geometry on tribological characteristics. Friction characteristics obtained for a distributed contact (pin-on-disc and block-on-ring), a linear concentrated contact (pin and vee-block and block-on-ring) and a point concentrated contact (ball-on-disc and three cylinder-cone) are presented. The wear scars were analysed using scanning electron microscopy (SEM) and energy dispersive spectrometry (EDS). The results show different values of friction and wear coefficients for the different types of contact geometry. The paper also assesses the effect of non-test characteristics, e. g., vibration.

The reduced s–d model with antiferromagnetically coupled impurity spins is tested on specific heat measurements of (La 1− x Ce x )Al 2 for varying Ce concentration c and magnetic field B . The s–d exchange coupling constant J , conduction bandwidth D and coupling between impurities γ 2 are adjusted to obtain the best fit of theoretical normalized specific heat c i ∗ (T,B) with experiment. The agreement between ERs-dM and experimental data, although limited by the different type of magnetic ordering observed in (La 1− x Ce x )Al 2 and predicted by the ERs-dM, appears to be satisfactory.

Extraction of As(III) and As(V) from sulphuric acids solutions of H2SO4 of various concentration (50–200 g/dm3 with Cyanex 923 dissolved in Exxsol 220/230 (50% v/v) was studied and compared. Cyanex 923 can be considered as an effective arsenic extractant. Sulphuric acid is co-extracted. Extraction both of As(III) and As(V) occurs quickly and the equilibrium is obtained after 5 minutes. The isotherms of As(III) and As(V) extraction at various sulphuric acid concentrations were determined and used to model the multistage countercurrent process. Arsenic can be stripped with water.

Extraction of arsenic(V) from sulfuric acid solutions with various extractants in multistage counter-current extraction-stripping systems was compared. The extraction ability of the extractants studied showed the following order: ENIM 100>TBP=CYANEX 923>2-methylhexanol. The extraction depends significantly on the number of extraction stages and the phase ratios in extraction. The effects of the number of stripping stages and the phase ratio in stripping are less important.

The reduced s-d model with antiferromagnetically coupled impurity spins, previously tested on susceptibility measurements of (La 1− x Ce x )Al 2 , is applied to CePd 2 Ga 3 . The s-d exchange coupling constant J , and conduction bandwidth D are adjusted to obtain the best fit of theoretical specific heat c i ( T , B ) and magnetization m i ( T , B ) with experimental c e ( T , B ), m e ( T , B ). The c i ( T , B ) and m i ( T , B ) curves coincide with the c e ( T , B ), m e ( T , B ) ones with high accuracy for | J | = 0.042 eV and D = 0.07 eV.

The first- and second-order terms of a perturbation expansion of free-energy density of the s-d exchange Hamiltonian with random impurity positions, in the presence and absence of an external magnetic field B, are evaluated. The reduced s-d Hamiltonian Hr(B) is chosen for the Hamiltonian of the unperturbed system. For weak fields B, the expansion takes different forms at temperatures T > Tc and T < Tc, Tc being the temperature at which Hr(B) exhibits a second-order phase transition.

The thermodynamic limit of free energy per electron lim ƒ(HF(n, M), β) (with the number of electrons n, number of impurities M and volume ¦Λ¦ tending to infinity under the constraints n¦Λ¦−1 = d, n−1M = v) of the reduced s-d Hamiltonian HF(n, M) with antiferromagnetic Ising and Heisenberg interactions between M spin S impurities is examined. It is shown that lim ƒ(HF(n, M), β) = lim ƒ(hF(n, M), β), where hF(n, M) represents a system of n electrons decoupled from M impurities which undergoes a second-order phase transition at Tc, accompanied at T < Tc by antiparallel alignment of impurity spins and those of mobile electrons with momenta close to the Fermi surface.

On the night of Oct 18/19, 2012 at 00:23 UT a -14.7 mag Orionid fireball occurred over northeastern Poland. The precise orbit and atmospheric trajectory of the event is presented, based on the data collected by five video and one photographic Polish Fireball Network (PFN) stations. The beginning height of the meteor is 168.4 +\- 0.6 km which makes the PF191012 Myszyniec fireball the highest ever observed, well documented meteor not belonging to the Leonid shower. The ablation became the dominant source of light of the meteor at a height of around 115 km. The thermalization of sputtered particles is suggested to be the source of radiation above that value. The transition height of 115 km is 10-15 km below the transition heights derived for Leonids and it might suggest that the material of Leonids should be more fragile and have probably smaller bulk density than in case of Orionids., 5 pages, 5 figures, accpeted for publication in Astronomy & Astrophysics

The antiarrhythmic effect of oral captopril was studied during the early (day 3) and late (day 14) phase of acute myocardial infarction among 304 patients in a randomized placebo-controlled substudy of ISIS-4. Ventricular arrhythmias (ventricular ectopic beats per hour) occurred significantly less frequently among captopril-allocated patients than among those allocated placebo at day 3 (logarithmic scale: 0·48 ± 0·8 captopril vs 0·84 ± 1·3 placebo; P

An antiferromagnetic equivalent-neighbour Heisenberg interaction Hi between impurity spins is added to the reduced s-d Hamiltonian Hr previously introduced by simplifying the Kondo s-d exchange Hamiltonian HK. Asymptotic mean-field theory is developed for Hr + Hi, in the presence and absence of external magnetic field, and applied to (La1−xCex)Al2 alloys. Specific heat ci(T) and zero-field susceptibility χi(0,T) curves for (La1−xCex)Al2 are depicted. The coupling constants of Hr + Hi and conduction bandwidth are adjusted so that Tc temperatures for x = 0.2, 0.1 are equal to the experimental values. ci(T) exhibits a jump at Tc and is decreasing for T 0. These results improve those obtained earlier on the grounds of Hr theory.

The Hamiltonian HK(B) of the spin 1 2 s-d exchange model in a uniform magnetic field B is reduced by a method previously applied to HK(0). The reduced s-d Hamiltonian Hr(B) is asymptotically equivalent in the thermodynamic limit to a mean-field hr(B), which exhibits a 2nd order phase transition at Tc if B is weak. hr(B) is applied to (LaCe)Al2 alloys. There is correspondence between theoretical and experimental curves of zero-field susceptibility χi(0, T): the theoretical χi(0, T) has a first-order pole at Tc, below the Kondo temperature TK; the experimental χie(0, T) curve has a finite maximum below TK. The zero-field theoretical specific heat of (LaCe)Al2 exhibits a finite discontinuity at Tc. Above Tc the expression for resistivity coincides with the one given by Kondo and the limiting T → 0 resistivity is finite.

Interfacial activity of 4-decylphenylamine was studied in model extraction systems. Szyszkowski equation, logarithmic polynomial and the spline function give similar estimations of adsorption parameters (surface excess and molecular area) in model systems of various acidities of the aqueous phase which do not contain electrolyte. They deviate significantly in systems containing NaCl. Interfacial activity of 4-decylphenylamine rises with an increasing aqueous phase acidity. Interfacial tension falls to low values in systems containing 3M HCl in aqueous phase. The formation of microemulsions is possible.

The interfacial activity of 2-hydroxy-5-tert-butylbenzaldehyde oxime was studied in systems containing toluene, octane, and mixtures of these diluents containing up to 20% toluene. A significant change in the interface character of the system containing 20% toluene is observed. The interface, however, is still not fully aromatic. For a system containing 1% toluene, the interface seems to have an aliphatic character.

The rate of growth of the left common carotid artery during gestation has not been sufficiently evaluated. The present study was performed on 128 spontaneously aborted human foetuses aged 15-34 weeks to compile normative data for the dimensions of the left common carotid artery at varying gestational ages. Using anatomical dissection, digital image analysis (system of Leica Q Win Pro 16) and statistical analysis (ANOVA, regression analysis), a range of measurements (length, original external diameter and volume) for the left common carotid artery during gestation was examined. No significant gender differences were found (p0.05). The growth curves of the best fit for the plot of each morphometric parameter against gestational age were generated. The lengths ranged from 14.82 +/- 2.22 to 42.84 +/- 4.32 mm, according to the linear model y = -9.6918 + 1.5963 x +/- 3.1706 (r = 0.95; p0.001). The original external diameter increased from 0.72 +/- 0.18 to 3.28 +/- 0.40 mm, according to the linear function y = -1.5228 + 0.1428 x +/- 0.2749 (r = 0.95; p0.001). The left common carotid artery-to-aortic root diameter ratio increased from 0.356 +/- 0.062 to 0.480 +/- 0.101. The left common carotid artery-to-aortic arch diameter ratio increased from 0.447 +/- 0.079 to 0.535 +/- +/- 0.113. The volume ranged from 6.73 +/- 4.06 to 369.30 +/- 107.42 mm3 in accordance with the quadratic function y = 344.8 - 41.001 x + 1.254 x2 +/- +/- 46.955 (R2 = 0.87). The parameters examined have clinical application in the early recognition of arterial abnormalities, especially aortic coarctation.

Interfacial tension isotherms were determined in hydrocarbon—water systems for 4-alkylphenylamines containing from 6 to 16 carbon atoms in their alkyl groups, and the surface excess isotherms were computed using various adsorption isotherms. Palladium (II) was extracted with 4-alkylphenylamines from 3 N HCl solutions. The maximum extraction rate of palladium (II) is observed for 4-decyl- and 4-dodecylphenylamines characterized by their best adsorption at the interface. Compounds easily soluble in the aqueous phase (4-hexylphenylamine) or in toluene (4-hexadecylphenylamine) extract palladium (II) slower than 4-decyl- and 4-dodecylphenylamines.

4-Octylphenylamine, decyl isonicotiniate, decyl nicotiniate, decyl 2-hydroxyethyl sulphide and its analg with partly fluorinated alkyl group were used for palladium(II) extraction from 3M HCl. The adsorption of these compounds at toluene/HCl solution was also studied and interpreted. 4-Octylphen adsorbs at the hydrocarbon/HCl solution at much lower concentration range than other extractants and can be used as a phase transfer catalyst. The addition of 4-octylphenylamine increases the extraction rate with esters of pyridine carboxylic acids and decreases the time needed to obtain the equilibrium of extraction.

Bacterial movement inside the cytoplasm is a major virulence factor in that it is necessary for efficient colonization of the infected tissues. Molecules from both the host and the pathogen present possible sites of pharmacologic intervention. Because locomoting Listeria and Shigella mimic the activated state of the leading edge of nonmuscle cells, these pathogens are powerful tools for dissecting the molecular machinery of actin-based motility. Analysis of the movement linked to cytoskeleton may lead to: (I) improved understanding of the mechanisms of disease transmission, including carriers and carrier states, pathogen movements, environmental factors and pharmacokinetics of the uptake and residues of vaccines and other biologics, and drugs in cultivated organisms; (II) new therapeutic developments, since it identifies the molecular targets involved in the pathogenicity of Listeria and Shigella and vaccinia intracellular enveloped virus. Recent knowledge about the intracellular movement in cytoplasm may lead to a better understanding of the processes governing actin dynamics within the cell and disease spread.

Od listopada 2002r. autorzy wykonali 5 rekonstrukcji wolnymi platami skornopowieziowymi z przedramienia po resekcjach raka przedniego odcinka dna jamy ustnej u 3 pacjentow i jezyka 2 pacjentow. Wszystkie rekonstrukcje wykonano jednoczasowo z resekcją. 1 pacjent byl leczony uprzednio radioterapią radykalną. U 3 pacjentow plat pobierano z przedramienia w niedokrwieniu stosując wycisk, u pozostalych niestosowano wycisku i mankietu. Zespolenia naczyniowe wykonywano w trzech przypadkach szwami nylonowymi 10/0, w dwoch szwami nylonowymi 7/0. Tetnice promieniową zespalano z jedną z galezi tetnicy szyjnej zewnetrznej lub z tetncą szyjną zewnetrzną koniec do konca. Żyle odpromieniową zespalano z galezią zyly szyjnej wewnetrznej koniec do konca. Plat wszywano starając sie odtwarzac w sposob anatomiczny ubytkipo resekcjach nowotworowych. Wyniki 1. Czterech pacjentow wygoilo sie bez powiklan, u jednego (pacjent po radioterapii) w drugiej dobie wystąpila zakrzepica zylna i mimo natychmiastowej rewizji plat ulegl martwicy, pacjent wymagal reoperacji i rekonstrukcji platem piesiowym. 2. Wszyscy wygojeni pacjenci mowili w sposob zrozumialy odzywiając sie bez problemow doustnie. Wnioski 1. Wolny plat skorno-powieziowy z przedramienia dzieki swojemu ksztaltowi jest latwy do modelowania i stanowi dobry material do rekonstrukcji po resekcjach niezaawansowanych nowotworow jamy ustnej. 2. Preparowanie i przygotowanie plata nie jest trudne, naczynia plata w porownaniu z naczyniami innych wolnych platow są stosunkowo szerokie, co znacznie ulatwia zespolenie. 3. U pacjentow po radioterapii nalezy szczegolną uwage zwrocic na wybor zylnego naczynia biorczego. W tym przypadku rozwazyc nalezy zespolenie zyly plata z zylą szyjną wewnetrzną koniec do boku.

The study of the mutant strain described here demonstrates that several characteristics contribute to maximal virulence of pathogenic strains of L. monocytogenes. The invasion levels of L. monocytogenes JB1115, a p60-deficient strain, were the same as for the parent strain L. monocytogenes 1043S in J774 macrophage-like cells. The invasion level of Listeria strains in Int407 cells was 100 times lower than in J774 cells. In epithelial Int407 cells, the time of division of p60- strain L. monocytogenes JB1115 was 43% slower than for the parent strain. In this study, two lisosomotrophic agents, ammonium chloride and chlorquinoline were tested in experimental L. monocytogenes 1043S and p60-deprived mutant JB1115 infection in both cell lines. The presence of ammonium chloride increased the level of infection (calculated as number of gentamicin-resistant cells) of both Listeria strains, but in the case of infection by p60 mutant, the increased amount of ammonium chloride showed only a minimal effect on the number of isolated bacteria. In both cell lines treated with chlorquinoline we observed a decrease in the number of viable intracellular bacteria isolated from infected monolayers. Our observation of parental and mutated strains of Listeria showed that phospholipase activity also depends on the presence of p60 protein. Mutated strain showed 31.46% reduction of PI-PLC activity measured in normal growth conditions. Protein p60 plays a role not only in listeriolysin O mediated haemolytic activity but full phospholipase C activity is also dependent on the presence of the Iap protein.

The numerical density of microglial cells is reduced by 47% in the corpus callosum, by 37% in the parietal cortex and by 34% in the frontal cortex of mice mutant at the op locus which are totally devoid of colony stimulating factor-1 (CSF-1), the major growth factor for macrophages. Moreover, microglia in the frontal cortex of the op/op mice are smaller and have shorter cytoplasmic processes compared to control mice. Study suggests that CSF-1 plays a role in vivo in the formation and maturation of microglia and has little or no effect on perivascular cells.

The aim of this study was to investigate the time of expression of the adhesion molecule platelet endothelial cell adhesion molecule-1 (PECAM-1/CD31) in the developing mouse blood-brain barrier (BBB). Ultrastructural studies employing a preembedding technique described herein demonstrate that PECAM-1 is initially expressed on the luminal and abluminal endothelial cell surfaces in the newborn animals. This adhesion molecule expression appears to increase in intensity at 7-10 days post partum and then decreases to a weak labelling of the luminal endothelial cell surfaces at two weeks after birth. Our results present immunocytochemical detection of active angiogenesis during early brain development in the mouse. Moreover, because of the important role that adhesion molecules play in immune responses in the central nervous system, upregulation of PECAM-1 prior to structural maturity of the BBB may suggest that the development of an "immune BBB" manifests prior to anatomical closure of the BBB in the mouse.

Brain of twelve, 44-78 years old non-demented patients affected by total ischemia after cardiac arrest, were used in the study. All of them were resuscitated within a few minutes after cardiac arrest and they survived for 3 to 36 days afterward. In all cases, after cardiac arrest, beta PP overexpression was found by immunocytochemical methods in many cortical and subcortical neurons as well as in ependymal and choroid plexus cells. This overexpression of beta PP, was concomitant with formation of many A beta nonfibrillar (thioflavine-negative) plaques in the neuropil. Because of a break in the blood-brain barrier around many vessels, weakly A beta-immunoreactive material was also found. The data presented provided strong evidence that the total brain ischemia resulting from cardiac arrest is a risk factor for beta-amyloidosis.