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In this study, electron diffraction patterns observed under high vacuum conditions for an SrTiO3 surface were interpreted in detail while paying special attention to the features of inelastic effects. The surface of the SrTiO2 was carefully prepared to enforce its termination with single domains of TiO2 layers at the top. The inelastic patterns were interpreted using analytical models. Two types of Kikuchi lines are recognized in this paper: those which can be described with the Bragg law and those which appear due to surface wave resonance effects. However, we also discuss that there exists a formal connection between the two types of the Kikuchi lines observed.

The successful synthesis of one-dimensional nanostructures of a narrow band gap semiconductor, exhibiting a ferromagnetic response at room temperature, is reported. High-quality nanowires of InSb-Mn have been produced by template-assisted pulse electrodeposition. Detailed structural and spectroscopic characterizations revealed good crystallinity, a narrow size distribution of the nanostructures, and the ability to control the Mn doping level. The dominating magnetic response at a cryogenic temperature evolves with an increasing Mn concentration from paramagnetic through antiferromagnetic to ferromagnetic. A robust ferromagnetic response of InSb nanowires doped with 2.5% at. of Mn is retained up to a Curie temperature of nearly 500 K.

Presented work focuses on the tremendous and often skipped role of pulse frequency on the structural, optical and electrical properties of electrodeposited InSb films. Tailoring the pulse frequency during electrodeposition allows to obtain stoichiometric, nanocrystalline, smooth films with relatively high electrical conductivity or Sb-rich, almost insulating, ultra smooth ones. It was observed that a double coherent domain size reduction (via decrease of pulse frequency) leads to a six fold increase in resistivity of the film. Further increasing pulse on time results in increasing resistivity of the material up to ca. 540 Ω cm. Based on the FTIR and SPV measurements it was confirmed that obtained materials are characterized by small band gap and p-type conductivity. Moreover, stoichiometric, ultra smooth InSb films obtained with 10 ms pulse on time have high photovoltage amplitude and charging time constant with relatively high conductivity, which makes them a good, low-cost candidate for optoelectronic devices.

Changes in stoichiometry, temperature, strain and other parameters dramatically alter properties of LSMO perovskite. Thus, the sensitivity of LSMO may enable control of the magnetic properties of the film. This work demonstrates the capabilities of interface engineering to achieve the desired effects. Three methods of preparing STO substrates were conducted, i.e., using acid, buffer solution, and deionized water. The occurrence of terraces and their morphology depend on the preparation treatment. Terraces propagate on deposited layers and influence LSMO properties. The measurements show that anisotropy depends on the roughness of the substrate, the method of preparing the substrate, and oxygen treatment. The collected results suggest that the dipolar mechanism may be the source of LSMO anisotropy.

Both preserved gapless states and gapping of Dirac states due to broken time reversal symmetry in bismuth chalcogenide topological insulators with surface and bulk magnetic impurities have been observed and reported in the literature. In order to shed more light on the mechanism of such effects we have performed comprehensive element selective study of the impact of Fe impurity position in the Bi2Se3 lattice on its magnetism. The iron atoms were imbedded in the structure (volume dopants) or deposited on the surface (adatoms) and they revealed striking phenomena. Volume doping preserves non-trivial topology of Bi1.98Fe0.02Se3. Fe atoms not only substitute Bi, but also locate in van der Waals gap. The former are magnetically isotropic, while the latter reveal large magnetic moment (4.5 μ B) with perpendicular anisotropy if located near the surface. Majority of Fe adatoms on the surface of Bi2Se3 exhibit weaker moment (3.5 μ B) with in-plane anisotropy, as expected for non-interacting species. Negligible interaction between surface electronic states and magnetic adatoms is confirmed by identical vibration spectra of Fe deposited on TI surface of Bi2Se3 and non-TI surface of Bi2S3. The data gathered show how indispensable is the knowledge of the magnetic impurity distribution for applications of bismuth chalcogenide systems.

The process of preparation of nanostructured thin films in high vacuum can be monitored with the help of reflection high energy diffraction (RHEED). However, RHEED patterns, both observed or recorded, need to be interpreted. The simplest approaches are based on carrying out the Ewald construction for a set of rods perpendicular to the crystal surface. This article describes how the utilization of computer graphics may be useful for realistic reproduction of experimental conditions, and then for carrying out the Ewald construction in a reciprocal 3D space. The computer software was prepared in the Java programing language. The software can be used to interpret real diffractions patterns for relatively flat surfaces, and thus it may be helpful in broad research practice.

Chalcopyrite-type (Cu–Fe–S2) ternary nanocrystals stabilized by long aliphatic chain ligands could be considered as isolated hard nanoobjects dispersed in a soft network of organic ligands. The main attention was paid to the behavior of the particles whose average size was varied in a controllable manner from 3 to 20 nm. Dynamics of the nanoparticles was studied by applying Mossbauer spectroscopy. The fast dynamics could be described by a two-level environment. The deeper level (atomic) was practically the same as for bulk material except for the Debye temperature, but the higher level (particle motion) was described by the classical harmonic oscillator with the spring constant dramatically softening with increasing temperature. Such behavior led to a fast decrease of the fraction detectable by Mossbauer spectroscopy with increasing temperature. The induced internal oscillations within a particle by the surrounding thermal bath additionally contribute to the shift of measured spectra. Slow dynamics was ch...

We investigate the use of Cu

The maximum magnetisation (saturation magnetisation) obtainable for iron oxide nanoparticles can be increased by doping the nanocrystals with non-magnetic elements such as zinc. Herein, we closely study how only slightly different synthesis approaches towards such doped nanoparticles strongly influence the resulting sub-nano/atomic structure. We compare two co-precipitation approaches, where we only vary the base (NaOH versus NH\(_3\)), and a thermal decomposition route. These methods are the most commonly applied ones for synthesising doped iron oxide nanoparticles. The measurable magnetisation change upon zinc doping is about the same for all systems. However, the sub-nano structure, which we studied with Mossbauer and X-ray absorption near edge spectroscopy, differs tremendously. We found evidence that a much more complex picture has to be drawn regarding what happens upon Zn doping compared to what textbooks tell us about the mechanism. Our work demonstrates that it is crucial to study the obtained structures very precisely when "playing'' with the atomic order in iron oxide nanocrystals.

We present an electrochemical route to prepare nanocrystalline InSb thin films that can be transferred to an industrial scale. The morphology, composition, and crystallinity of the prepared uniform and compact thin films with a surface area of around 1 cm2 were investigated. The essential electrical characteristics such as conductivity, Seebeck coefficient, the type, concentration and mobility of charge carriers have been examined and compared with InSb nanowires obtained in the same system for electrochemical deposition (fixed pulse sequence, temperature, electrolyte composition, and system geometry). Moreover, obtained thin films show much higher band gap energy (0.53 eV) compared to the bulk material (0.17 eV) and InSb nanowires (0.195 eV).

We carried out comprehensive structural, magnetic and toxicity studies of Mg1−xZnxFe2O4 and Cu1−xZnxFe2O4 ferrites that we plan to use as contrast agents for magnetic resonance-imaging thermometry. Samples were prepared by a standard ceramic technique. Their structural properties were investigated with an x-ray diffraction system, and data was analyzed using the Rietveld method that allowed us to determine cations distribution. Magnetic properties of MgZn and CuZn ferrites were studied using a superconducting quantum interference device magnetometer, a vibrating sample magnetometer, and Mossbauer spectrometer. Magnetometry measurements were cross-correlated with XRD results and compared with magnetic properties determined by Mossbauer spectroscopy, allowing us to understand the magnetic structure of studied ferrites. The temperature dependent magnetic measurements were used as guidance to select the most suitable MgZn and CuZn ferrites compositions for MRI thermometry near human body temperature. The inflammation studies indicated that MgZn ferrites are more suitable from the toxicology point of view for MRI thermometry.

Here, we demonstrate heteroepitaxial growth of MgO/TiN thin films on flexible metal foil of copper substrates using pulsed laser deposition. X-ray and electron diffraction measurements revealed that the epitaxial MgO/TiN bilayer was oriented along [002] direction. The large mismatch between TiN film and Cu substrate was effectively reduced by the 5/6 and 6/7 variations of domains. Despite the local irregularity of misfit dislocations at TiN/Cu, the domain-matching epitaxy paradigm is a remarkably accurate theory. MgO/TiN bilayer is chemically homogeneous and Mg, Ti, or Cu atoms do not segregate into the low-angle grain boundaries regardless of MgO/TiN films thickness. Thus, it appears that thickness may be reduced up to the value in which TiN fully covers the rough surface of Cu tape. Unfortunately, issues related to the presence of in-plane TiN contraction, probably generated by the difference in thermal expansion coefficient, and the origin of misfit dislocations irregularity at TiN/Cu interface remain unresolved. Our findings can make a substantial contribution to further research on Cu-based coated conductors and help in better understanding the ways that MgO/TiN bilayer are grown on Cu tape.

We investigate the use of Cu1-x Zn x Fe2O4 ferrites (0.60 < x < 0.76) as potential sensors for magnetic- resonance-imaging thermometry. Samples are prepared by a standard ceramic technique. Their structural and magnetic properties are determined using x-ray diffraction, scanning electron microscopy, super-conducting quantum-interference device magnetometry, and Mossbauer and 3-T nuclear-magnetic-resonance spectroscopies. We use the mass magnetization of powdered ferrites and transverse relaxivity r*2 of water protons in Ringer's-solution-based agar gels with embedded micron-sized particles to determine the best composition for magnetic-resonance-imaging (MRI) temperature sensors in the (280-323)-K range. A preclinical 3-T MRI scanner is employed to acquire T*2 weighted temperature-dependent images. The brightness of the MRI images is cross-correlated with the temperature of the phantoms, which allows for a temperature determination with approximately 1°C accuracy. We determine that the composition of 0.65 < x < 0.70 is the most suitable for MRI thermometry near human body temperature.

The growing demand for clean energy catalyzes the development of new devices capable of generating electricity from renewable energy resources. One of the possible approaches focuses on the use of thermoelectric materials (TE), which may utilize waste heat, water, and solar thermal energy to generate electrical power. An improvement of the performance of such devices may be achieved through the development of composites made of an organic matrix filled with nanostructured thermoelectric materials working in a synergetic way. The first step towards such designs requires a better understanding of the fundamental interactions between available materials. In this paper, this matter is investigated and the questions regarding the change of electrical and thermal properties of nanocomposites based on low-conductive polypyrrole enriched with bismuth nanowires of well-defined geometry and morphology is answered. It is clearly demonstrated that the electrical conductivity and the Seebeck coefficient may be tuned either simultaneously or separately within particular Bi NWs content ranges, and that both parameters may be increased at the same time.

The pattern of microhabitat preferences of Ukrainian brook lamprey Eudontomyzon mariae ammocoetes was examined in two rivers of central Poland: the Pilica River (the Vistula River basin) and the Grabia River (the Odra River basin). A comparison of abiotic factors of the rivers revealed differences in water speed and principal components: PC1 (determining gradient from decreasing medium sand to the increasing share of three fractions of gravel), PC2 (a gradient from the declining share of very coarse and coarse sand fractions to the growing content of fine sand) and PC3 (correlated with an increasing proportion of silt). The sites did not differ significantly in terms of water depth. Relative abundance and frequency of ammocoete occurrence in the Grabia River were higher than in the Pilica River. Only speed, PC1 and PC2 made a significant contribution to the prediction of larval occurrence. Eudontomyzon mariae larvae preferred substrata with a reduced amount of medium sand and increased content of gravel (PC1) as well as with a lower content of coarse sand and higher proportion of fine-grained sand (PC2). The ammocoetes also preferred areas with a water speed of 0A‚·2 m s(-1) but avoided speeds A¢Â‰Â¥ 0A‚·6 m s(-1). The abundance of E. mariae was affected by water speed, as well as by all PCs. The mean A‚± s.e. optimal current speed was 0A‚·265 A‚± 0A‚·007 m s(-1), while abundance decreased with increasing amounts of gravel (PC1) and increased with increasing amounts of fine sand and silt in the bottom substratum (PC2 and PC3). Comparison of ammocoete microhabitat use in the Pilica and Grabia Rivers showed the lack of differences in distribution in the preferred values of current speed, PC1 and PC2.

The paper presents the physical properties of soft magnetic iron composites and Nd-Fe-B bonded permanent magnets measured at room temperature and at liquid nitrogen. The objective of research was a determination of influence of liquid nitrogen temperature on the magnetic properties, resistivity and mechanical properties of different powder magnetic materials. Research was carried out for three powder materials: soft magnetic, i.e. Somaloy 700, AncorLam and hard magnetic powder MQP-B used for production of bonded magnets. Composite specimens were prepared by compression moulding technology.

Diabetic foot ulceration poses a significant threat of osteomyelitis (OM) and subsequent amputation. The diagnosis of OM via imaging studies is difficult as radiographic findings do not present immediately and advanced imaging studies may be contraindicated or unavailable. A novel diagnostic tool has been developed which synthesises technetium-99 white blood cell-labelled single-photon emission computed tomography and computed tomography (Tc99mWBC labelled-SPECT/CT) imaging, effectively enhancing anatomic detail. The aim of this pilot study was to determine the validity and reliability of this novel imaging technique in patients with diabetic foot ulcers in a Veterans Affairs healthcare facility. A retrospective review was performed on consecutive patients who met the inclusion criteria (n = 14) and underwent Tc99mWBC-labelled SPECT/CT for suspected OM. Histopathologic analysis of bone specimen (when available) and International Working Group on the Diabetic Foot consensus criteria were used as a reference standard. The sensitivity and specificity of Tc99mWBC-labelled SPECT/CT were 87·50% [confidence interval (CI): 64·58–110·42%] and 71·43% (CI: 37·96–104·90%), respectively. Negative predictive value (NPV) and positive predictive value (PPV) were 83·33% (CI: 53·51–113·15%) and 77·78% (CI: 50·62–104·94%), respectively, with a likelihood ratio (LR) of 3·063 and an accuracy of 80%. These findings suggest Tc99mWBC-labelled SPECT/CT can be useful in imaging OM in patients with diabetic foot ulcers.

Magnetic properties of Fe based composite materials with different particle sizes under a cryogenic condition have been investigated. Realisation of this venture has been carried out at the liquid nitrogen temperature. Results of energy loss density were obtained from measurements of the static (dc) hysteresis cycles ranging from 0·1 to 1·0 T. In turn, results of power loss density were obtained from measurements of the dynamic (ac) hysteresis cycles ranging from 50 to 1000 Hz and at the maximum flux density of 0·5, 0·8 and 1·0 T. The study confirmed the influence of temperature on magnetic parameters. It has been shown that total power loss density has increased with decreasing temperature. We report changes in a nature of energy loss after immersing specimens made of soft magnetic composites in liquid nitrogen. Measurements of the maximum relative permeability were also conducted.

Adenoviral infections of the central nervous system are rare, but they are characteristic for their high mortality rate. People with impaired immunity and children are particularly vulnerable. A few reports of neuroinfections caused by adenoviruses are found in literature. In this study the tropism of the human adenoviruses type 4, 5, 7 to primary cultures of murine neurons and the influence of infection on the neuron morphology and actin cytoskeleton was examined. The A549 non-small-cell lung cancer cell line was used as a reference line. Viral effects upon the cell culture were evaluated by direct immunofluorescence. The levels of adenovirus replication in the above-mentioned cell cultures were determined by real-time PCR. In the current study we demonstrated for the first time that human adenovirus (HAdV) type 4, 5 and 7 exhibits tropism for neurons cultured in vitro followed by the extensive replication of all serotypes in the primary culture of murine neurons. Immunofluorescent labelling and confocal microscopy revealed the changes in cell morphology, destruction of actin cytoskeleton and cell lysis as the final stage of infection. According to the obtained results we can assume that productive cycle of HAdV in the studied cell cultures occurred. We also observed accumulation of nuclear actin within nuclei of infected cells which may indicate that it plays role in adenovirus infection and replication in neurons and A549 cells.

Correction for ‘Electrochemically deposited nanocrystalline InSb thin films and their electrical properties’ by K. E. Hnida et al., J. Mater. Chem. C, 2016, 4, 1345–1350.

Corneal transplants have one of the highest success rates among all transplantological procedures. Corneas intended for transplantation are stored in a preservation fluid, which is then tested for bacterial and fungal infections. Among all analyses of infectious complications following corneal transplants, infections caused by bacteria or fungi are the most prominent. Surprisingly, however, apart from a few publications, there is a lack of data regarding the occurrence of viruses in donor corneas and the risk of transmitting these to their recipients. The intention of this research was therefore to determine the frequency with which human herpesvirus 1 (HHV-1), human herpesvirus 2 (HHV-2), and human adenovirus (HAdV) occur in transplanted corneal tissue, as well as in samples of preservation fluid. The study comprised 57 paired samples, with each pair consisting of a fragment of the corneal tissue remaining after its trepanation for transplantation surgery and a sample of corneal preservation fluid. Sample pairs were all tested for the presence of the DNA of three viruses (HHV-1, HHV-2, and HAdV) using real time PCR technique. Viral DNA was found in three of the tested corneas-HHV-1 DNA in one paired sample (1.8%) and adenovirus DNA in two single samples (3.5%). We postulate that virological testing of corneas for transplantation should be considered, particularly in the case of donors with increased risk factors for herpesvirus and adenovirus reactivation. J. Med. Virol. 89:732-736, 2017. © 2016 Wiley Periodicals, Inc.

It is demonstrated that ternary Cu–Fe–S nanocrystals differing in composition (from Cu-rich to Fe-rich), structure (chalcopyrite or high bornite) and size can be obtained from a mixture of CuCl, FeCl3, thiourea and oleic acid (OA) in oleylamine (OLA) using the heating up procedure. This new preparation method yields the smallest Cu–Fe–S nanocrystals ever reported to date (1.5 nm for the high bornite structure and 2.7 nm for the chalcopyrite structure). A comparative study of nanocrystals of the same composition (Cu1.6Fe1.0S2.0) but different in size (2.7 nm and 9.3 nm) revealed a pronounced quantum confinement effect, confirmed by three different techniques: UV-vis spectroscopy, cyclic voltammetry and Mossbauer spectroscopy. The optical band gap increased from 0.60 eV in the bulk material to 0.69 eV in the nanocrystals of 9.3 nm size and to 1.39 eV in nanocrystals of 2.7 nm size. The same trend was observed in the electrochemical band gaps, derived from cyclic voltammetry studies (band gaps of 0.74 eV and 1.54 eV). The quantum effect was also manifested in Mossbauer spectroscopy by an abrupt change in the spectrum from a quadrupole doublet to a Zeeman sextet below 10 K, which could be interpreted in terms of the well defined energy states in these nanoparticles, resulting from quantum confinement. The Mossbauer spectroscopic data confirmed, in addition to the results of XPS spectroscopy, the co-existence of Fe(III) and Fe(II) in the synthesized nanocrystals. The organic shell composition was investigated by NMR (after dissolution of the inorganic core) and IR spectroscopy. Both methods identified oleylamine (OLA) and 1-octadecene (ODE) as surfacial ligands, the latter being formed in situ via an elimination–hydrogenation reaction occurring between OLA and the nanocrystal surface.

We report on an effect of CoPt layer thickness on the magnetic properties of 3D CoPt-Pt multilayered nanowire arrays. The nanowires exhibit ferromagnetic behavior for the CoPt segments even only a few nanometers thick. It was found that decreasing thickness of CoPt nanosegments, by shortening the time of ‘magnetic material pulse’ during electrodeposition, leads to a stronger dependence of magnetization on temperature and the decrease of critical temperature. Also other magnetic parameters such as ground state magnetization, spin-wave parameter and Bloch exponent were determined for the CoPt-Pt nanowire arrays. The ground-state values of magnetization suggest that the mixing of Co and Pt occurs within the whole segment’s volume, however, the segments remain ferromagnetic. It is demonstrated that temperature dependencies of magnetization qualitatively follow the predictions of the spin-wave theory. Furthermore, based on the angle-dependent measurements of magnetization versus applied magnetic field, the coherent spin rotation was determined as a mechanism of magnetization reversal in the CoPt-Pt multilayered nanowire arrays.

Magnetite (Fe 3 O 4 ) thin films have been grown epitaxially on zinc oxide (ZnO) substrates, using reactive molecular beam epitaxy. The film quality was found to be strongly dependent on the oxygen partial pressure during growth. For a uniform Fe 3 O 4 film a certain pressure variation was needed during growth. Structural, electronic, and magnetic properties were analyzed utilizing low energy electron diffraction, Hard X-ray Photoelectron Spectroscopy (HAXPES), Magneto-Optical Kerr Effect (MOKE), and X-ray Magnetic Circular Dichroism (XMCD). Diffraction patterns show clear indication for growth of Fe 3 O 4 in the [111] direction on ZnO(0001). Non-destructive depth profiling by HAXPES revealed uniform magnetite thin films. Both, MOKE and XMCD measurements show easy in-plane magnetization. The dichroic spectra clearly support the formation of Fe 3 O 4 .

The paper deals with methods of tailoring magnetic properties of soft and hard magnetic composites. Comparison of magnetic properties of injection moulding and compression moulding Nd-Fe-B magnets are presented. Magnetic properties of Nd-Fe-B bonded magnets were tailored by different ways such as: amount of resin, addition of barium ferrite, Al or Fe powders. Influence of technological parameters such as compression pressure, time and temperature of curing on magnetic parameters of Nd-Fe-B bonded magnets are presented in the paper. Magnetic properties of soft magnetic composites made of Fe, Ni, Co are presented in the paper. Influence of technological parameters such as compression pressure, time and temperature of curing on magnetic parameters of iron soft magnetic composites are presented also in the paper.

The current global epidemic of type two diabetes mellitus has led to an accompanying increase in both foot ulceration and amputations, which pose significant health problems to populations worldwide. If improved treatment options are to be offered, then we clearly need a better understanding of all aspects of this disease. To date the major focus of diabetes research has been on physical factors, which are undeniably important, but there has been little acknowledgement of the significant psychological effects that can influence health and delay wound healing. The ‘health locus of control’ (HLC) theory, a psychological theory concerning patients' perceptions of how much control they have over life events (both positive and negative) may well be of use in this patient group. It has been suggested that concordance with treatment is improved when patients have a high ‘internal’ HLC (as measured by a questionnaire), which aligns with the belief that they have greater control over their health. It has further been suggested that through the implementation of ‘group-care’ education programmes, patients' attitudes can change, with a shift towards higher ‘internal’ HLC values. Thus a new approach in patient management might be to implement such education programmes, in the hope of improving adherence to treatment regimens and, hence, patient outcomes. To date there has been little conclusive evidence of the application of this theory, and although various studies have been performed in diabetic populations, only one study has been conducted specifically regarding diabetic foot ulcers. Clearly more research is needed.

The feeding habits of spirlin Alburnoides bipunctatus were investigated in a tributary of the River Vistula (Poland). To evaluate size-related patterns of resource use, fish were assigned to three size classes, defined according to size at first maturation: small (29–70-mm total length, TL), medium (71–90mm TL) and large (91–104mm TL). There was a significant ontogenetic shift in the feeding pattern among size classes, marked by differences in the proportion of the main taxonomic groups of prey consumed: small spirlin primarily consumed chironomid larvae, whereas medium and large spirlin showed a preference for Coleoptera, Ephemeroptera and imagines of unidentified insects. The proportion of prey taken from the water column was significantly lower for small- than medium- and large-sized spirlin. This difference was attributed to the benthic habits of small spirlin compared with medium and large spirlin. The shift to open water feeding in spirlin corresponded with sexual maturation, with habitat segregation between the smallest size class (comprising juveniles) and larger size classes (mature individuals). Size-specific changes in the diet composition of this species have not previously been documented.

The CXCR4 chemokine receptor is a seven transmembrane G protein-coupled receptor present on the surface of various cells including cancer cells. The CXCR4 receptor contributes to the induction of several intracellular signalling pathways that enhance survival, proliferation, and migration of malignant cells. We observed that tamoxifen (Tam) reduced the CXCR4 transcript and protein levels in MCF-7 breast cancer cells. However, we did not see a Tam effect on CXCR4 transcript and protein levels in MCF-7(LVMT3B) cells with RNA interference-mediated knockdown of DNMT3B. We also observed that Tam significantly increased, for several hours, the expression of enzymatically active DNMT3B splice variants in MCF-7 cells. However, there was no Tam effect on these DNMT3B splice variants' expression in MCF-7(LVMT3B) cells. Bisulfite sequencing suggests that Tam may reduce CXCR4 expression via increased methylation of cytosine in the cytosine-guanosine (CpG) dinucleotide island of the CXCR4 promoter of MCF-7 breast cancer cells. Our findings suggest that Tam induces an increase in DNMT3B expression that is associated with the increase of CpG dinucleotide methylation in the CXCR4 promoter and significant reduction of CXCR4 gene expression in MCF-7 cells.

Electrophoretic variation of 13 presumptive enzymatic loci was studied in sticklebacks (Gasterosteus aculeatus) at 6 marine (Baltic) and 13 freshwater sites from Poland. Marine samples are significantly more variable (proportion of polymorphic loci, p # 0.38) than freshwater Samles (p # 0.12). Also the mean number of alleles per locus is significantly higher in the marine samples (n # 1.54) than in freshwater samples (n # 1.14). There is however no significant difference in values of mean heterozygosity between marine and freshwater sticklebacks. Some alleles are found in Baltic sticklebacks only, but all these occur in very low frequencies. Genetic distance between samples is low ranging from D = 0.000053 to 0.031410. However D is significant smaller between marine samples than between freshwater Samles. We suggest than this probaily is the result of larger genetic subdivision of freshwater populations. The low genetic divergence of marine and freshwater populations of the stickleback from poland might be expfained by the recent postglacial colonization of this area from a common refugium.

The coevolutionary dynamics between European bitterling Rhodeus amarus and freshwater unionid mussels, which the former parasitize by laying eggs on their gills, were tested. In a series of experiments fish preferences and mussel responses were compared in parasites and hosts of recent (Europe) and ancient (Asia) sympatry. Rhodeus amarus readily oviposited on the gills of all mussel species tested. Fish that laid their eggs on the gills of Asian Anodonta woodiana, however, suffered a dramatic reduction in reproductive success compared to fish that oviposited on the gills of European mussels: Unio pictorum, Unio tumidus, Anodonta anatina and Anodonta cygnea. This difference was the result of egg ejection behaviour by mussels rather than the unsuitability of the internal gill environment for European bitterling embryo development. The ejection response of mussels with a long sympatry with European bitterling was considerably more pronounced than that of mussels with a substantially shorter sympatry. The data support a coevolutionary arms race between bitterling and mussels and point to an evolutionary lag in the relationship between R. amarus and its European mussel hosts. (c) 2007 The Authors. Journal compilation (c) 2007 The Fisheries Society of the British Isles.

The pattern of microhabitat preferences of Ukrainian brook lamprey Eudontomyzon mariae ammocoetes was examined in two rivers of central Poland: the Pilica River (the Vistula River basin) and the Grabia River (the Odra River basin). A comparison of abiotic factors of the rivers revealed differences in water speed and principal components: PC1 (determining gradient from decreasing medium sand to the increasing share of three fractions of gravel), PC2 (a gradient from the declining share of very coarse and coarse sand fractions to the growing content of fine sand) and PC3 (correlated with an increasing proportion of silt). The sites did not differ significantly in terms of water depth. Relative abundance and frequency of ammocoete occurrence in the Grabia River were higher than in the Pilica River. Only speed, PC1 and PC2 made a significant contribution to the prediction of larval occurrence. Eudontomyzon mariae larvae preferred substrata with a reduced amount of medium sand and increased content of gravel (PC1) as well as with a lower content of coarse sand and higher proportion of fine-grained sand (PC2). The ammocoetes also preferred areas with a water speed of 0·2 m s(-1) but avoided speeds ≥ 0·6 m s(-1). The abundance of E. mariae was affected by water speed, as well as by all PCs. The mean ± s.e. optimal current speed was 0·265 ± 0·007 m s(-1), while abundance decreased with increasing amounts of gravel (PC1) and increased with increasing amounts of fine sand and silt in the bottom substratum (PC2 and PC3). Comparison of ammocoete microhabitat use in the Pilica and Grabia Rivers showed the lack of differences in distribution in the preferred values of current speed, PC1 and PC2.

The objective of this study was to evaluate the ability of a preoperative serum CA125 to predict whether optimal debulking (OD) could be achieved for patients with stage III and IV epithelial ovarian cancer (EOC). The records of consecutive patients who underwent primary surgery for EOC at Indiana University Hospital between January 1997 and January 2003 were reviewed. Eligibility criteria included FIGO stage III/IV disease, surgery by gynecologic oncology faculty, preoperative CA125, and an operative note clearly defining volume of residual disease. The Medcalc software statistical package was used to generate a receiver-operating characteristic (ROC) curve. Two hundred and eighty-nine cases of stage III/IV EOC were identified, of which 164 met the eligibility criteria. Serum CA125/=400 was associated with OD/=75% of the time. Conversely, OD was achieved in/=40% of patients with CA125/=4500. The area under the ROC curve for CA125 was .670. The OD rate for those with and without ascites was 49% and 79%, respectively (P0.001). In a multivariate analysis using CA125, age, and ascites, the area under the curve was 0.686. We conclude that preoperative serum CA125 did not reliably predict OD in patients with stage III-IV EOC.

Summary We examine the evolving concept of what constitutes a nonnative (or alien) freshwater fish. In an attempt to distinguish between biogeographical and socio-political perspectives, we review the patterns in the introduction and dispersal of nonnative fishes in Europe and North America, and especially the recent expansion of Ponto-Caspian gobies in Europe. We assess patterns in the development of national policy and legislation in response to the perceived threat of non-native fish introductions to native species and ecosystems. We review, and provide a glossary of, the terms and definitions associated with non-native species. Finally, we discuss perspectives as regards the future treatment of naturalized species.

GEANT is the pan-European 10 Gbs network interconnecting European national research and educational networks (NRENs). A Premium IP service based on the DiffServ EF PHB has been specified and implemented for this environment to provide quality of service to selected user groups on a Europe-wide scale. Basic features of Premium IP are described, and results from early experiments in the production networks of GEANT and the NRENs are presented. Next steps are proposed for achieving a fast and wide availability of Premium IP in the European research networks.

We report on the structural and magnetic characterization of Ni/Fe/MgO/Fe structures grown on GaAs(001) and InP(001). High-resolution transmission electron microscopy images confirm a good crystallographic order of the structures grown on GaAs(001). On the contrary, the structures grown on InP(001) do not show any long-range crystallographic order. For structures grown on GaAs(001), magneto optic Kerr effect analysis shows steps in the hysteresis loops corresponding to magnetization reversal processes that occur independently in both ferromagnetic (FM) films. No FM coupling between the bottom Fe and the top Ni/Fe films is detected. The coercivity of the bottom Fe film in the junction is increased in comparison to the Fe/GaAs(001) film of the same thickness most likely due to crystallographic defects. The defects are created in the top Ni/Fe bilayer and are spread over the whole single-crystalline structure. For structures grown on InP(001), a strong FM coupling is deduced from the hysteresis loops and is interpreted in terms of the orange-peel coupling.

We report on the magnetic and structural characterization of Au/(Ni)Fe/MgO/Fe magneto-tunnel junctions grown on InP(0 0 1) and GaAs(0 0 1). On GaAs substrates almost perfect single crystal junctions with sharp interfaces were achieved as seen by low energy electron diffraction and transmission electron microscopy. In situ magnetization loops obtained with the longitudinal magneto-optic Kerr effect show an independent switching of magnetization of both Fe layers suggesting that the two Fe layers are magnetically decoupled by the MgO layer.