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The fission probability of $$^{238}$$ 238 Np was measured as a function of the excitation energy in the energy range of E$$^* = 5.4 - 6.2$$ ∗ = 5.4 - 6.2 MeV in order to search for transmission fission resonances. A radioactive $$^{237}$$ 237 Np target was bombarded with deuterons of E$$_d$$ d = 12 MeV, whereas the energy of the protons was analyzed with a superior resolution of $$\varDelta $$ Δ E = 8 keV. The experiment was performed at the Tandem accelerator of the Maier-Leibnitz Laboratory in Garching employing the $$^{237}$$ 237 Np(d,pf) reaction. A group of fission resonances has been observed at excitation energies between E$$^* = 5.5 - 5.8$$ ∗ = 5.5 - 5.8 MeV, which could be ordered into three (superdeformed) rotational bands with a rotational parameter of $$\hbar ^2/2\varTheta = 3.507$$ ħ 2 / 2 Θ = 3.507 keV, and identified as the first direct observation of transition states composing rotational bands in an odd-odd nucleus as they appear above the top of the outer fission barrier. Nuclear reaction code (talys1.95) calculations were also performed to extract the multi-humped fission barrier parameters of $$^{238}$$ 238 Np by fitting them to the experimental data of the present (d,pf) and previous (n,f) experiments. The extracted barrier parameters also support the above interpretation of the observed resonances.

To ensure clinical success, the implant and the surrounding bone tissue must not only be integrated, but also must not be suspected of infection. In this work, an antibacterial and bioactive nanostructured calcium silicate (CaSi) layer on titanium substrate by an electrospray deposition method was prepared, followed by annealing at 700, 750 and 800 °C to improve the bonding strength of the CaSi coating. The phase composition, microstructure and bonding strength of the CaSi coatings were examined. Human mesenchymal stem cells (hMSCs), Gram-negative Escherichia coli (E. coli) and Gram-positive Staphylococcus aureus (S. aureus) species were used to analyze the osteogenic and antibacterial activity of the coatings, respectively. Experimental results showed that the as-prepared CaSi coating was mainly composted of β-dicalcium silicate phase with a particle size of about 300 nm. After annealing, the thickness of the oxidation reaction layer increased obviously from 0.3 μm to 1 μm with increase in temperature, which was confirmed by the cross-sectional morphology and element depth profile. The bonding strength of the coating annealed at 750 °C (19.0 MPa) was significantly higher (p < 0.05) than that of the as-prepared coating (4.4 MPa) and the ISO 13,779 standard (15 MPa). The results of antibacterial efficacy and stem cell osteogenesis consistently elaborated that the 750 °C-annealed coating had higher activity than the as-prepared coating and the Ti control. It is concluded that after annealing at 750 °C, the CaSi nanoparticle-coated Ti implant had good bond strength, osteogenic and antibacterial activity.

Formation and transformation of micron-sized structures on PbTe crystal surfaces under impact of low energy Ar+ ions is studied. New phenomena occurring due to interaction of energetic ions and atoms forming the main crystallographic planes of solid crystalline compounds, namely the transformation of ion-induced conical structures into pyramidal ones and the formation of facets of the micropyramids with well-ordered ripples during the process of transformation are revealed. We show that conical-pyramidal transformations occur on any PbTe sputtering surface, but the shape of pyramidal structures depends on the surface crystallographic orientation. If the pyramid originates from the ion-induced conical structure on PbTe target of (100) orientation it has the tetrahedral shape and its facets are covered with pronounced well-ordered ripples arranged in parallel to the base of the pyramid and closed at its edges. We show that: (i) micro-sized conical structures ion-induced on PbTe surface are transformed into pyramidal ones due to the tendency of the PbTe compound to the easy cleavage along crystallographic planes of high reticular density; (ii) the well-ordered ripples on the facets of the tetrahedral pyramids forming from conical structures appear due to self-organization of {111} and {110} crystallographic planes shaping pyramidal facets.

Charged-particle induced radioluminescence (RL) of CsPbBr3 (CPB) perovskite quantum dots (QD) in their clustered state was investigated using α-particles from a radiation source. The RL response was analyzed with photomultiplier tubes (PMT) combined with the pulse-digitization technique, which enabled the evaluation of time-resolved waveforms for individual α-radiation events. The rising and decay transition times of electric pulses were found very close to the instrumental limitation, while orders of magnitude shorter than typically measured in conventional inorganic scintillators. Based on the statistical analysis of timing characteristics, our study assessed the potentials of employing perovskite nanomaterials in precise timing applications as demonstrated in a comparative measurement with a CsI(Tl) scintillator. The distribution of pulse charge was converted to luminescence intensities, which were fitted with Monte Carlo simulations giving an estimate of 2.95 photon/keV for the RL yield and 29.2% for detection efficiency (DE), referring to our mean cluster thickness of 5 QD layers.

The exact partition function, free energy, pair-correlation function, and connected quantities like entropy, specific heat, and magnetic susceptibility were deduced for an Ising chain in which each spin interacts with its mirror-image spin and the neighbors of the image. A qualitatively different behavior was found for the pair-correlation function in low- and high-temperature limits, which was interpreted in terms of bound spin pairs emerging in the low-T regime. The physical implications of the model are analyzed, and applications in condensed matter and biology discussed. \textcopyright{} 1996 The American Physical Society.

Author attempted to collect all available medical data of the period of the reign of Mathias Corvinus (1443-1490) who ruled Hungary for 32 years. First part of this article outlines the general medical history of this era. In the 15th century the flourishing Kingdom of Hungary was inhabited by 3-3.2 million people. Under the rule of King Matthias epidemies were frequent visitors, plague e.g. was registered 11 times, while sudor anglicus once (in 1485). The ca. 120 hospitals of the era were founded mostly in towns and market-towns. At the same time 12 leprosories worked throughout the country. Strikingly many dates and details could be collected concerning medical doctors and surgeons working in Hungary. A list of 69 medical doctors and surgeons (60 physicians and 9 surgeons) of this era known by their names is attached to the article. The second and third part of the treatise is a medical history of King Matthias of his relatives and of his court. We can read here a report on the illnesses and death of Janus Pannonius and of Joannes Vitéz who both played an important role in Hungarian culture. Author's further inquiry is focused on diseases and death of the king. Cause of his death was--according to contemporary sources and our present-day knowledge--a cerebral apoplexy. On 6th April 1490 Matthias died suddenly but not unexpected, since his health had already been deteriorated critically during the previous two years, and he had long been crippled by gout. The king's condition had been worsened probably as an effect of factors caused by visceral form of gout. These factors were cardiovascular and renal damages and hypertension, which resulted the fatal cerebral apoplexy causing the king's sudden death.

The flutter instability analysis of a bridge deck is based on flutter derivatives determined by wind tunnel tests on a section model having two degrees of freedom, heave and pitch (hereafter referred to as the heave-pitch model). The imperfections and the eccentricity that arise during the forced sinusoidal vibration of the section yield erroneous derivatives. This paper studies the relationship between these errors and the imperfections. Rotational excitations around two eccentric axes (hereafter referred to as the pitch-pitch model) of the section model show that the determined derivatives are less error-prone to imperfections. Determining the derivatives, like angular speed flutter derivative A_2^\ast for the aeroelastic torsion moment, gives a more accurate value, so the flutter instability analysis yields a more accurate estimate of the flutter wind speed. Numerical values are presented for the case of a thin airfoil and a bluff bridge cross section.

An Ising chain with mirror-image type interactions was analyzed exactly at nonzero temperatures. However the thermodynamic function of the model is analytic, a careful study revealed an accentuately rich internal physics whose interpretation in terms of correlation functions lead us to consider hidden internal ordering within the system at least of short-range type.

The isoscalar giant dipole resonance (ISGDR), which is the lowest-energy overtone mode of the isoscalar giant resonances, has been studied in some medium-heavy and heavy nuclei in coincidence measurements. The observation of the direct nucleon decay channels significantly helped to enhance giant resonance strengths with respect to the underlying background and continuum, which gave an indication for the existence of a new mode with L = 2 character, assumingly the overtone of the ISGQR.

Sharp transmission resonances have been observed in the U-235(d, Pf) U-236 reaction. The shapes of the resonances as well as the angular distributions of the associated fission fragments are analyzed together with the data obtained previously for U-234. The resonances are interpreted as being hyperdeformed rotational bands with (h) over bar(2)/2 theta = 1.8(-0.7)(+0.5) and 1.6(-0.4)(+1.0) keV and K values of 1, 2, and 4 for U-234 and U-236, respectively.