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•Cell cycle re-entry accounts for most new cardiomyocytes and endothelial cells in the adult heart.•The extracellular matrix is a key source of molecules that regulate heart cell behaviour.•Fibroblasts change their phenotype to resolve inflammation after phagocytosing apoptotic cells.

In this work, we report the sol-gel alkoxide route preparation of nanostructured SiO2 and TiO2 powders as well as TiO2-SiO2 thin films obtained by dip-coating. Thermal analysis, morphology and structure were characterized for powders and correlation between preparation method and optical properties of binary materials (SiO2-TiO2) for thin films was approached. Spectroscopic Ellipsometry (SE), Fourier Transform Infrared Spectroscopy (FTIR) and scanning electron microscopy (SEM) have been used for the physical characterization of the films.

Abstract: The magnetic nanocomposite materials represent an important class of nanomaterials extensively studied nowadays due to their varied applications from medical diagnostic to storage information. The iron oxides in silica matrix systems are highly investigated. The sol-gel method is a suitable way of preparation of Fe3O4-SiO2 nanocomposite materials, since this method allowed the preparation of nanocomposite materials with narrow size distribution of magnetite in silica matrix. In the present work, nanocomposite materials in the Fe3O4-SiO2 system were prepared by sol-gel method via alkoxide and aqueous route. As SiO2 sources, tetraethoxysilan (TEOS) for the alkoxide route, as well as silica sol Ludox (30%) for the aqueous route, were used. This study shows the influence of the type of silica matrix on the structure, size, and distribution of the Fe3O4 nanoparticles in the Fe3O4-SiO2 systems. The gels were annealed at 550°C in order to consolidate the matrices. The structural characterization of the obtained materials via the two preparation routes was performed by DTA/TGA analysis, X-ray diffraction, IR and Mössbauer spectroscopy, Transmission Electron Microscopy (TEM) and Selected Area Electron Diffraction (SAED).

Abstract: The magnetic nanocomposite materials represent an important class of nanomaterials extensively studied nowadays due to their varied applications from medical diagnostic to storage information. The iron oxides in silica matrix systems are highly investigated. The sol-gel method is a suitable way of preparation of Fe3O4-SiO2 nanocomposite materials, since this method allowed the preparation of nanocomposite materials with narrow size distribution of magnetite in silica matrix. In the present work, nanocomposite materials in the Fe3O4-SiO2 system were prepared by sol-gel method via alkoxide and aqueous route. As SiO2 sources, tetraethoxysilan (TEOS) for the alkoxide route, as well as silica sol Ludox (30%) for the aqueous route, were used. This study shows the influence of the type of silica matrix on the structure, size, and distribution of the Fe3O4 nanoparticles in the Fe3O4-SiO2 systems. The gels were annealed at 550C in order to consolidate the matrices. The structural characterization of the obtained materials via the two preparation routes was performed by DTA/TGA analysis, X-ray diffraction, IR and Mssbauer spectroscopy, Transmission Electron Microscopy (TEM) and Selected Area Electron Diffraction (SAED).

Abstract: We study the behavior of the nonzero temperature quantum nonlinear sigma model in d = 2 dimensions at finite temperatures in the presence of the damping term. Using the renormalization group (RG) method we calculated the effect of the finite temperature on the magnetic coherence length and the damping of the fluctuations. The results have been used to calculate the relaxation rates from nuclear magnetic resonance, which have been analyzed phenomenologically by different authors in order to get the phase diagram in the doped cuprate superconductors. Our calculations showed a good agreement with the experimental data, but we also evaluated the corrections which appear due to a more accurate analysis performed using the RG method.

Abstract: We study the behavior of the finite temperature quantum nonlinear sigma model in two dimensions in the presence of the damping of the formf (|θ n |) = γ|ω n |α, whereα satisfiesα ≥ 1. The analytical calculations will be performed usingα=2 and the results will be compared with the standard results obtained for the standard quantum nonlinear sigma model. The behavior of such a system is connected with the pseudogap which appears in the normal state of the cuprate superconductors.

We analyze the non-Fermi liquid behavior in the proximity of the quantum phase transition induced by the strong polarization of the electrons due to local magnetic moments in NixPd1-xalloys. We use the renormalization group approach introduced by Hertz–Mi11is–Moriya (HMM) to estimate the temperature dependence of the electrical resistivity for the case of three dimensional itinerant ferromagnets. We study two different cases, namely, the clean and disordered ferromagnets, and argue that at the present time more experimental data are needed to decide if the HMM theory can accurately describe the physical properties in NixPd1-xalloys.

The effective mass in heavy fermion materials is calculated, taking into consideration both the antiferromagnetic and ferromagnetic fluctuations. The temperature and the proximity of a quantum critical point effects are considered. The effective mass diverges at the quantum critical point and in the zero temperature limit.

We showed that in a d-wave two-dimensional superconductor the disorder given by non-magnetic impurities at low temperature leads to a non-Fermi behavior for the normal state. The transition is similar to the superconductor–insulator transition in a model with a dissipative term.

We propose a model for the explanation of the non-Fermi behavior near the ferromagnetic quantum phase transition. The scaling equations have been used to calculate the specific heat and we showed that the quantum effects are responsible for the Tln Tterm from the specific heat. The results are in agreement with recent experimental data obtained in the NixPd1 − xsystem. The relation with the other approaches was also discussed.

We used the Renormalization Group (RG) method in the Hertz–Millis version to study the quantum phase transition of the itinerant-electron ferromagnet. Near the quantum phase transition point the system present a non-Fermi behavior in agreement with the experimental results. The importance of long-range interactions considered by Belitz–Kirkpatrick–Vojta was taken into consideration, showing the importance of the marginal parameters.

We derive the expression of the specific heat of a three-dimensional semimetal near a zero-temperature phase transition with dynamic exponent z. The result showed the occurrence of a non-Fermi behavior for z = 3, according to the general conjecture that the systems with d = z may present a T ln T contribution in the specific heat, which is typical for the non-Fermi behavior.

Composite SiO2—iron oxide materials were prepared by three experimental procedures. In the first case, the iron oxides were precipitated during a sol-gel process. In the second case, a SiO2matrix was initially obtained, and the iron oxides were formed by thermal treatment after impregnation of a soluble Fe2+salt in the previously processed matrix. In the third method, ferrite powders, prepared by wet chemical method, were embedded into a SiO2based sol-gel matrix. Materials with convenient porosity and nano-sized iron oxide content could be prepared using the mentioned methods. The prepared composite has been tested for arsenic(V) removal.

We studied the influence of the electron–boson interaction (hybridization) on the bosonic spectrum in the case of a two dimensional (2D) electronic system. The boson dispersion is affected by this interaction and we showed that for a constant density of states the wavevector dependence is quadratic for qvF/4T≪ 1, and the imaginary part is small for qvF/4T≫ 1. However, the 2D electronic system presents a van Hove density of states, and we considered this energy dependence in the calculation of the bosonic energy spectrum. The real part becomes logarithmic dependent on the wavevector and the imaginary part can be neglected if qvF∼ EFor 2 Ec∼ z,for qvF/4T≫ 1.

The electronic self-energy due to the electron–spin fluctuation interaction is calculated using the one loop approximation for a two-dimensional system and quasi-two-dimensional (anisotropic) model. We analyzed the relevance of the diffusive modes and the temperature dependence of the magnetic correlation length for a possible temperature dependence of the pseudogap.

We consider a two-dimensional (2D) Fermi liquid with attraction in the dchannel. The critical temperature, the order parameter at T= 0 and the temperature dependence of the order parameter have been calculated analytically for a constant, an ɛr-energy dependent, and a van Hove density of states.

The critical temperature of a superconductor with a non-Fermi liquid ground state has been calculated. The density of states has two different forms and is energy dependent. The critical values of the coupling factor λ were calculated. The constant density of states results are obtained as particular cases. These results are an extension of the work done by Grosu et al.[Phys. Rev. B56, 8298 (1997)].

The gels which are precursors of TiO2porous materials are prepared by the controlled hydrolysis-condensation of titanium isopropoxide by polymeric method. In the present work, a study of the influence of different experimental conditions (water/alkoxide ratio, solvent/alkoxide ratio and temperature) on the structure and texture of the polymeric gels obtained with the same type of alkoxide has been investigated. The structural and textural modifications for the unsupported materials have been detected using DTA/TGA, XRD, specific surface area and pore size computerized measurements. The optical properties of the supported materials deposited on silicon wafers have been investigated using ellipsometric method. Supported and unsupported porous materials with different structure and texture have been obtained depending on different experimental and thermal treatment conditions.

We used the flow equation method to obtain from the electron–magnon Hamiltonian an effective electron–electron Hamiltonian with renormalized single-particle energy. In the Cooper channel the electron–electron interaction was found to be attractive. The energy scale of the superconducting critical temperature is determined by the spin splitting, which gives rise to the realistic energy scale.

We discussed the validity of the Abrikosov–Gorkov formula for the description of the decreasing of Tcin the d-pairing superconductors. A scaling behavior of Tcwith the concentration of nonmagnetic impurities has been obtained in the unitary limit scattering. The average of the impurities has also been discussed in different models and we showed that the validity of the procedure is sensitive to the ratio R= 2Δ(0)/Tc.

The gels which are precursors of TiO2porous materials are prepared by the controlled hydrolysis-condensation of titanium isopropoxide by polymeric method. In the present work, a study of the influence of different experimental conditions (water/alkoxide ratio, solvent/alkoxide ratio and temperature) on the structure and texture of the polymeric gels obtained with the same type of alkoxide has been investigated. The structural and textural modifications for the unsupported materials have been detected using DTA/TGA, XRD, specific surface area and pore size computerized measurements. The optical properties of the supported materials deposited on silicon wafers have been investigated using ellipsometric method. Supported and unsupported porous materials with different structure and texture have been obtained depending on different experimental and thermal treatment conditions.

Damping of the quasiparticles in a layered two-dimensional electron gas has been calculated including the electron-phonon and electron-electron interaction. The calculations performed atT=0 andT?0 show that the non-Fermi behavior can appear as in the case of the electron-plasmon interaction, but it is also enhanced by the presence of the phonons.

The critical temperature of a pairing model for HTcS has been calculated using an energy-dependent density of states. We showed that the problem which is connected with the van Hove scenario is very sensitive to the energy scale and to the behavior of the density of states at low and high energy.

The critical temperature of a layered superconductor has been calculated using the model of an electron-bosonic pairing. Influence of impurities has been considered using for the bosonic propagator the modified plasmonic propagator. The main result is a decreasing of the critical temperature due to the nonmagnetic impurities. The results are important for the case of high critical temperature superconductors doped with nonmagnetic impurities.

The temperature dependence of a marginal Fermi liquid has been calculated. We showed that the expectedT lnT correction is characteristic for the low-temperature domain. The high-temperature domain has a supplementary correction. The results are in agreement with the non-Fermi behavior of some metallic systems the in low-temperature domain.

The possibility of a coexistent superconducting and magnetic phase in layered transition metal dichalcogenides of the type MX2Ax is investigated (M =transition metal; X = S, Se; A = magnetic ion; x = 0.25). Describing such systems with a model in which a highly anisotropic electron gas interacts with a quasi-two-dimensional Heisenberg magnet, we find the following conditions for coexistence: (1) The coupling between adjacent layers of ferromagnetically ordered magnetic ions needs to be antiferromagnetic ( = 0) in order to have no pair-breaking internal fields. (2) The exchange interaction between conduction electrons and magnetic ions must be very small (? 0.003 eV), since otherwise, due to the high concentration of localized magnetic moments, spin-flip scattering processes and spin fluctuations would destroy superconductivity. The theoretical prediction for the persistence of superconductivity up to concentrations of x˜ 0.25 of magnetic ions is compared with recent experiments on Eu-intercalated TaS2 and NbS2 and related compounds showing a tendency for ferromagnetically ordered layers of Eu impurities and antiferromagnetic coupling between neighboring layers but no superconductivity for x exceeding a few percent. Reasons for the quick disappearance of superconductivity in these systems and criteria for possible observation of “high-magnetic-impurity-concentration superconductivity” in other layered compounds are given.

We present a calculation of the coexistence of superconductivity and ferromagnetism in the s-d model for the case when the exchange interaction between the ferromagnetically aligned d electrons and the conduction electrons is weak and the effects can be considered of the first order. The equations for the order parameter and the polarization of the conduction electrons have been derived using a Green's function method for two limiting cases: (a) a d-function density of states and (b) a constant density of states.

Abstract:: We derive the jump in the specific heat at T=T c for a superconductor in a non-Fermi liquid model. We took into consideration the two possible limits in this problem: the spin-charge separation model for a Fermi liquid and the usual non-Fermi liquid model which satisfies the homogeneity relation for the spectral function $$A(\Lambda k,\Lambda \omega ) = {\Lambda ^{ - 1 + \alpha }}A(k,\omega )$$. We also derive the order parameter behavior for these two cases in the vecinity of the critical temperature.

This paper reports a 28-year-old woman with Philadelphia chromosome (Ph1)-positive chronic myeloid leukemia (CML) who developed two marrow cell lines during the blastic phase: one with the translocation (12; X) (q 11; p 22) and the other with the translocation (4; 6) (p 16; q 25). The literature on involvement of chromosomes 12 and X in translocations and the appearance of 6 q- aberration in CML is summarized. The relationship between the 6 q- aberration and the blast cells with lymphoid appearance in the plastic phase of CML is discussed.

Abstract: The critical temperature of a superconductor with a layered structure has been calculated. The influence of the electron-electron and electron-phonon interaction was considered in a microscopic model based on the layered two-dimensional Fermi gas. The calculations have been performed using the influence of the electron-phonon interaction on the Coulomb potential. An increasing of the critical temperatureT c was obtained due to the influenceof the electron-phonon interaction.

Abstract: It is shown that a single impurity can produce a pair of bound states inside the gap of thes-wave van Hove superconductor. Both nonmagnetic and magnetic states have been considered using the Anderson Hamiltonian. The results are discussed relative to the case of the classical spin in thes-wave van Hove superconductor.

We study the crossover between weak coupling and strong coupling in two-dimensional (2D) superconductors atT⊋0 in the weak coupling regime, described by the BCS state, and we calculate the order parameter and the chemical potential atT=0andT⊋0 for the model of a 2D superconductor. In the strong coupling regime the energy excitation has the scale of the pairs generated by the attractive interaction. The order parameter and the chemical potential atT⊋0 are calculated, and we show that there is a continuous transition between the two regimes.

Following the flow equations given by Wegner, we study the single impurity state in a 2D superconductor with an energy-dependent density of states. The Anderson model withU= 0 has been used to perform analytical calculations of the single impurity energy in a superconductor with different energy spectrum. We showed that the single impurity energy is drastically affected by an energy-dependent density of states. For the 2D van Hove superconductor the correction is of the order of δ2.

The temperature dependence of the thermal conductivity for a superconducting spin-glass is calculated, taking a short-range spin-spin interaction in a superconductor carrying a uniform flow. The presence of the short-range interaction between frozen spins gives rise to a strong depression in the thermal conductivity.

Abstract: We calculated the self-energy atT = 0 for a two-dimensional fermionic system with hyperbolic dispersion. The existence of the saddle points in the energy gives rise to a marginal behavior, a result which has been obtained by numerical calculations.

Abstract: he pair breaking effect in the critical temperature has been considered. We showed that the decrease in the critical temperature can be described by an Abrikosov-Gorkov-like formula which contains the correction due to the van Hove density of states.

An algebric method of the renormalization group equations is proposed in order to study the field theory with multiple coupling constants for Γi= 0. The method is applied to a non abelian gauge theory with two scalar fields.

Abstract: The deviation of the superconducting transition temperature from the Abrikosov-Gorkov behavior in the case of La1−xGd x is explained considering the presence of short range spin-glass at low temperature. The theoretical results show good agreement with the experimental data.

The nuclear spin relaxation rateT1-1 is calculated for a disordered two dimensional highcritical temperature superconductor taking into consideration the inelastic scattering of the electrons on the impurities. The deviation from the Korringa law of the formT1-1 =AT+ B has been obtained if the quantum correction to the transport is dominated by the magnetic correlations.

We calculated the self-energy of a Fermi system interacting with bosonic excitation. If the bosonic system is near instability, the imaginary part of the self-energy which measures the lifetime of quasiparticles is of the order of (?(p)-?F) which is typical for a marginal Fermi liquid. Such a behavior can appear for three- and two-dimensional Fermi systems.

The self-energy of a layered two-dimensional (2D) electron gas interacting with localized spins has been calculated in the Fermi liquid approach. The (2D) electron-spin interaction gives rise to a spin gap in the energy spectrum, and if we include the plasmonic excitations a marginal behavior can occur for different values of the interlayer distance. The electron-spin interaction gives as the main effect the enhancement in the energy scale of the electronic excitations.

Using the Eliashberg equations, we calculated the critical temperature of a two-dimensional superconductor with strong disorder. The retarded Coulomb interaction and the magnetic correlations have been included in the renormalization function Z(?). The critical temperature decreases with the concentration of impurities, in agreement with the experiments.

The imaginary part of the self-energy of a two-dimensional Fermi system interacting with bosonic excitations has been calculated analytically and numerically. The result shows a marginal Fermi liquid behavior. The model can be a reasonable approach for studying the marginal behavior of a two-dimensional Millis-Monien-Pines phenomenological model.

We analyze the electron-boson interaction using many-body methods in the framework of the marginal Fermi liquid theory. Special attention is paid to the approximations necessary to obtain a marginal behavior. We show that the effective coupling constant between electrons is attractive on the entire energy scale. The renormalization of the bosonic spectrum due to the Coulomb interaction is also analyzed.

The effect of disorder on the phononic-plasmonic microscopic model for high-critical-temperature superconductors has been studied. The dynamic screening of the Coulomb interaction due to the disorder results in a decrease inTc. For a two-dimensional electronic system the plasmon modes are strongly affected by disorder. Taking this effect into consideration, we show thatTc can decrease but there is also an additional effect to the phonon-plasmon attractive contribution.

he pair breaking effect in the critical temperature has been considered. We showed that the decrease in the critical temperature can be described by an Abrikosov-Gorkov-like formula which contains the correction due to the van Hove density of states.