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[en] A new indium(III) fluoride complex with the ammonium cation (NH4)2[InF5] is synthesized and its crystal structure is studied. The structure of (NH4)2[InF5] is formed of NH4+ cations and complex [InF5]2- anions. The In atom in the complex anion surrounded by four terminal and two bridging F atoms forms an almost regular octahedral coordination polyhedron (CN 6) with two terminal F atoms in the axial positions and two terminal and two bridging F atoms in the equatorial plane. Through bridging F atoms, the InF6 polyhedra are arranged in polymer trans- vertex-connected corrugated anion chains (InF5)n2n- directed along the c axis. The N-H..F hydrogen bonds organize the chains in a three-dimensional framework.
[en] The paper represents a rigorous treatment of the underlying quantum theory, not just in words but providing the underlying technical details, as to why matter occupies so large a volume and its intimate connection with the Pauli exclusion principle, as more and more matter is put together, as well as of the contraction or shrinkage of “bosonic matter”, upon collapse, for which the Pauli exclusion is abolished. From the derived explicit bounds of integrals of powers of the particle number densities, explicit bounds on probabilities of the occurrences of the events just described are extracted. These probabilities lead one to infer the change of the “size” or extension of such matter, upon expansion or contraction, respectively, as their content is increased. (general)
[en] Several studies came to the conclusion that chaotic phenomena are worth including in high school and undergraduate education. The double pendulum is one of the simplest systems that is chaotic; therefore, numerical simulations and theoretical studies of it have been given large publicity, and thanks to its spectacular motion, it has become one of the most famous demonstration tools of chaos, either through simulations or in real experiments. Although several attempts have been made to use the experiment in laboratory exercises, as the friction in the real experiment changes the nature of the motion and the values of characteristic parameters during the motion, examining the measured (dissipative) motion and comparing it with theoretical results raises several questions. In our review, we present a measurement system which is able to analyse these questions. The system, which consists of simple yet precise data acquisition electronics, easily attainable sensors, a Bluetooth module (to communicate with the PC) and open-source software, demonstrates on-line the main characteristics of chaos and the methods of its study and allows us to analyse the dissipative motion. Further information (including downloadable software) is provided on a dedicated page, http://www.inf.u-szeged.hu/noise/Research/DoublePendulum/. (paper)
[en] We prove the existence of weak solutions in the space of energy for a class of nonlinear Schrödinger equations in the presence of a external, rough, time-dependent magnetic potential. Under our assumptions, it is not possible to study the problem by means of usual arguments like resolvent techniques or Fourier integral operators, for example. We use a parabolic regularisation, and we solve the approximating Cauchy problem. This is achieved by obtaining suitable smoothing estimates for the dissipative evolution. The total mass and energy bounds allow to extend the solution globally in time. We then infer sufficient compactness properties in order to produce a global-in-time finite energy weak solution to our original problem.
[en] We have studied the structural evolution of crystalline InCl starting from an amorphous deposit, generated by PVD on a sapphire substrate kept at -196 and -228 C. The first crystalline modification occurred at heating up to -100 C and was identified as β-InCl, the high temperature modification. Formation of metastable β-InCl at the conditions given can only be rationalized by assuming control of phase formation by more efficient nucleation of the metastable, low density polymorph in accordance with the Ostwald-Vollmer rule. At 70 C the system becomes sufficiently activated that the equilibrium polymorph α-InCl occurs, which in a reversible process finally transforms to β-InCl. During subsequent cooling to room temperature the α-InCl is recovered. (Copyright copyright 2013 WILEY-VCH Verlag GmbH and Co. KGaA, Weinheim)
[en] Highlights: • Femoral metastatic disease impairs patients’ quality of life and prognosis. • Surgical management may deleteriously impair patients’ survival. • Several different minimally invasive interventional treatments have been proposed. • Percutaneous image guided osteosynthesis has been reported with promising results. - Abstract: Aim: To present percutaneous image-guided screw-mediated osteosynthesis (PIGSMO) for fixation of impending fractures (ImF) and non-displaced/mildly displaced pathological/insufficient fractures (PF/InF) of the femoral neck in non-surgical cancer patients. Materials and methods: This is a double-centre single-arm observational study. Retrospective review of electronic records identified all oncologic patients who had undergone femoral neck PIGSMO. Inclusion criteria were: non-displaced or mildly displaced PF/InF, and ImF (Mirels’ score ≥8); life expectancy ≥1 month; unsuitability for surgical treatment due to sub-optimal clinical fitness, refusal of consent, or unacceptable delay to systemic therapy. Results: Eleven patients were treated (mean age 63.7 ± 13.5 years) due to ImF (63.6%, mean Mirels’ score 10.1), PF (27.3%) or post-radiation InF (9.1%) under CT/fluoroscopy- (36.4%) or CBCT- (63.6%) guidance. Thirty-two screws were implanted and cement injection was added in 36.4% cases. Technical success was 90.9%. No procedure related complications were noted. At 1-month clinical follow-up (pain/walking impairment), 63.6% and 27.3% patients reported significant and mild improvement, respectively. Imaging follow-up (available in 63.6% cases) showed no signs of secondary fractures, neither of screws loosening at mean 2.8 months. Five patients (45.5%) died after PIGSMO (mean time interval 3.6 months). Conclusions: PIGSMO is technically feasible and safe in cancer patients with limited life expectancy; it offers good short-term results. Further prospective studies are required to corroborate mid- and to prove long-term efficacy of the technique.
[en] Chenopodium album and C. murale are cosmopolitan, annual weed species of notable economic importance. Their unique biological features, including high reproductive capacity, seed dormancy, high persistence in the soil seed bank, the ability to germinate and grow under a wide range of environmental conditions and abiotic stress tolerance, help these species to infest diverse cropping systems. C. album and C. murale grow tall and absorb nutrients very efficiently. Both these species are allelopathic in nature and, thus, suppress the germination and growth of native vegetation and/or crop plants. These weed species infest many agronomic and horticultural crops and may cause > 90% loss in crop yields. C. album is more problematic than C. murale as the former is more widespread and infests more number of crops, and it also acts as an alternate host of several crop pests. Different cultural and mechanical methods have been used to control these weed species with varying degrees of success depending upon the cropping systems and weed infestation levels. Similarly, allelopathy and biological control have also shown some potential, especially in controlling C. album. Several herbicides have been successfully used to control these species, but the evolution of wide-scale herbicide resistance in C. album has limited the efficacy of chemical control. However, the use of alternative herbicides in rotation and the integration of chemicals and biologically based control methods may provide a sustainable control of C. album and C. murale.
[en] In this paper, we attempt to understand complex network evolution from the underlying evolutionary relationship between biological organisms. Firstly, we construct a Pfam domain interaction network for each of the 470 completely sequenced organisms, and therefore each organism is correlated with a specific Pfam domain interaction network; secondly, we infer the evolutionary relationship of these organisms with the nearest neighbour joining method; thirdly, we use the evolutionary relationship between organisms constructed in the second step as the evolutionary course of the Pfam domain interaction network constructed in the first step. This analysis of the evolutionary course shows: (i) there is a conserved sub-network structure in network evolution; in this sub-network, nodes with lower degree prefer to maintain their connectivity invariant, and hubs tend to maintain their role as a hub is attached preferentially to new added nodes; (ii) few nodes are conserved as hubs; most of the other nodes are conserved as one with very low degree; (iii) in the course of network evolution, new nodes are added to the network either individually in most cases or as clusters with relative high clustering coefficients in a very few cases. (general)
[en] We have applied fast-ion-beam laser-fluorescence spectroscopy to measure the isotope shifts of 73 optical transitions in the wavelength range 421.5–455.8 nm and the hyperfine structures of 35 even parity and 33 odd parity levels in Gd II. Many of the isotope shifts and hyperfine structure measurements are the first for these transitions and levels. These atomic data can be used to correct for saturation and blending in the analysis of stellar spectra to determine chemical abundances. As a result, they have an important impact on studies of the history of nucleosynthesis in the Universe and on the use of photospheric abundance anomalies in Chemically Peculiar stars to infer indirect information about stellar interiors. - Highlights: • Extensive set of new precision laser spectroscopy data on Gd II. • Hyperfine structure of 68 levels measured. • Isotope shifts of 73 optical transitions measured. • Important atomic data for astrophysical stellar spectroscopy.
[en] The spectra of sets of optical fundamental functions are determined for an indium-bromide crystal in the range of 0–30 eV at 4.2 K for the polarizations E ∥ a and E ∥ c. The calculations are carried out using experimental reflection spectra R(E) and several software packages. Their basic features are established.