Your email was sent successfully. Check your inbox.

An error occurred while sending the email. Please try again.

Proceed reservation?

Export
  • 1
    ISSN: 1572-9834
    Keywords: Climatic change ; eco-hydrology ; evapotranspiration ; soil moisture ; water resource problems ; Poland
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology
    Notes: Abstract The impact of climatic change on variables of concern to eco-hydrology was examined. Long time series of records of temperature, precipitation and river flow for Poznan were analyzed and forecasts of tendencies were made. Spatial distribution of runoff and of the ratio of evapotranspiration to precipitation was obtained for the country. It was found likely that the dynamics of the hydrological cycle will accelerate. Annual precipitation, runoff and evapotranspiration will increase. The joint effect, including estimated growth in water demand, is likely to be a decrease in the amount of soil moisture.
    Type of Medium: Electronic Resource
    Signatur Availability
    BibTip Others were also interested in ...
  • 2
    Electronic Resource
    Electronic Resource
    Springer
    The European physical journal 36 (1987), S. 665-667 
    ISSN: 1434-6052
    Source: Springer Online Journal Archives 1860-2000
    Topics: Physics
    Notes: Abstract The gauge-fixing terms of the free, real-time thermal gauge field propagators corresponding to quantization in a covariant gauge obtained by Kobes, Semenoff, and Weiss are shown to be incorrect, apart from well-known signature ambiguities in the off-diagonal elements, and to differ from those obtained by Landsman using the method of the Klein-Gordon divisor. We obtain the correct forms which are then shown to coincide with Landsman's results by means of a distributional identity.
    Type of Medium: Electronic Resource
    Signatur Availability
    BibTip Others were also interested in ...
  • 3
    ISSN: 1573-5001
    Keywords: GATA-1 ; protein-protein interactions ; solution structure ; zinc finger
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology , Chemistry and Pharmacology
    Notes: Abstract Zinc fingers (ZnFs) are generally regarded as DNA-binding motifs. However, a number of recent reports have implicated particular ZnFs in the mediation of protein-protein interactions. The N-terminal ZnF of GATA-1 (NF) is one such finger, having been shown to interact with a number of other proteins, including the recently discovered transcriptional co-factor FOG. Here we solve the three-dimensional structure of the NF in solution using multidimensional 1H/15N NMR spectroscopy, and we use 1H/15N spin relaxation measurements to investigate its backbone dynamics. The structure consists of two distorted β-hairpins and a single α-helix, and is similar to that of the C-terminal ZnF of chicken GATA-1. Comparisons of the NF structure with those of other C4-type zinc binding motifs, including hormone receptor and LIM domains, also reveal substantial structural homology. Finally, we use the structure to map the spatial locations of NF residues shown by mutagenesis to be essential for FOG binding, and demonstrate that these residues all lie on a single face of the NF. Notably, this face is well removed from the putative DNA- binding face of the NF, an observation which is suggestive of simultaneous roles for the NF; that is, stabilisation of GATA-1 DNA complexes and recruitment of FOG to GATA-1-controlled promoter regions.
    Type of Medium: Electronic Resource
    Signatur Availability
    BibTip Others were also interested in ...
  • 4
    ISSN: 0020-7608
    Keywords: coupled-cluster theory ; electron correlation effects ; molecular orbital choice ; reference determinant choice ; quasi-degenerate states ; Chemistry ; Theoretical, Physical and Computational Chemistry
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Notes: The impact of the choice of molecular orbital sets on the results of single-reference-state coupled-cluster (CC) methods was studied for the H4 model. This model offers a straightforward way of taking into account all possible symmetry-adapted orbitals. Moreover, the degree of quasi-degeneracy of its ground state can be varied over a wide range by changing its geometry. The CCD, CCSD, and CCSDT approaches are considered. Surfaces representing the dependence of the energy on the parameters defining the orbitals are obtained. It is documented that for every method there exist alternative orbital sets which allow one to obtain more accurate energies than the standard (HF, BO, and NO) ones. However, for many of the former orbital sets, one obtains relatively large one-body amplitudes or one may encounter problems with solving the CC equations by conventional methods. An interesting variety of orbitals which might be useful for studies of quasi-degenerate states by the CCD method was found.   © 1998 John Wiley & Sons, Inc. Int J Quant Chem 67: 205-219, 1998
    Additional Material: 5 Ill.
    Type of Medium: Electronic Resource
    Signatur Availability
    BibTip Others were also interested in ...
  • 5
    ISSN: 1089-7690
    Source: AIP Digital Archive
    Topics: Physics , Chemistry and Pharmacology
    Notes: The structure and physical significance of the full set of solutions to coupled-cluster (CC) equations at various stages of the dissociation process and the impact of the choice of reference functions on these solutions have been studied for the first time. The equations for the CC method involving double excitations (CCD) are obtained for the P4 model consisting of two H2 molecules in a rectangular nuclear configuration determined by a geometry parameter α. We consider equations for the reference states |ΦA〉, |ΦQ〉, and |ΦB〉 corresponding to the lowest, highest, and intermediate Hartree–Fock (HF) energies, respectively. The first two states provide a size-consistent description of the dissociation process. For the compact-molecule geometries (α〈10.0) the sets of complete solutions to the standard CCD equations [based on molecular orbitals (MOs) of D2h symmetry] in the spin–orbital and spin–symmetry-adapted versions always consist of 20 and 12 entries, respectively. For |ΦA〉 and |ΦB〉 in the dissociation limit (α→∞) only for the latter version the solutions can be attained by homotopy method. In this case we have reformulated the standard spin–symmetry-adapted CCD equations to a version based on the use of localized orbitals (LO) which is extremely simple and can be solved analytically providing an understanding of the unexpected peculiarities of the solutions for α→∞. For |ΦA〉 and |ΦQ〉, there are only two regular solutions. For the remaining 10 solutions, the CCD wave functions are meaningless despite the fact that the corresponding CCD energies are equal to the exact values. © 1999 American Institute of Physics.
    Type of Medium: Electronic Resource
    Signatur Availability
    BibTip Others were also interested in ...
  • 6
    Electronic Resource
    Electronic Resource
    College Park, Md. : American Institute of Physics (AIP)
    Journal of Mathematical Physics 38 (1997), S. 2483-2505 
    ISSN: 1089-7658
    Source: AIP Digital Archive
    Topics: Mathematics , Physics
    Notes: It is demonstrated that nonlinear dynamical systems with analytic nonlinearities can be brought down to the abstract Schrödinger equation in Hilbert space with boson Hamiltonian. The Fourier coefficients of the expansion of solutions to the Schrödinger equation in the particular occupation number representation are expressed by means of the classical orthogonal polynomials. The introduced formalism amounts to a generalization of the classical methods for linearization of nonlinear differential equations such as the Carleman embedding technique and Koopman approach. © 1997 American Institute of Physics.
    Type of Medium: Electronic Resource
    Signatur Availability
    BibTip Others were also interested in ...
  • 7
    Electronic Resource
    Electronic Resource
    College Park, Md. : American Institute of Physics (AIP)
    Journal of Mathematical Physics 42 (2001), S. 4138-4147 
    ISSN: 1089-7658
    Source: AIP Digital Archive
    Topics: Mathematics , Physics
    Notes: The Bargmann representation is constructed corresponding to the coherent states for a particle on a sphere introduced in Kowalski and Rembielinski, J. Phys. A: 33, 6035 (2000). The connection is discussed between the introduced formalism and the standard approach based on the Hilbert space of square integrable functions on a sphere S2. © 2001 American Institute of Physics.
    Type of Medium: Electronic Resource
    Signatur Availability
    BibTip Others were also interested in ...
  • 8
    ISSN: 0020-7608
    Keywords: Computational Chemistry and Molecular Modeling ; Atomic, Molecular and Optical Physics
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Notes: Single-reference coupled-cluster methods corresponding to various approximate forms of the cluster operator including up to four-electron operators are applied to the simple H4 model system with the aim of numerically studying the attainability and properties of multiple solutions of the systems of nonlinear equations for the cluster amplitudes. Various solutions have been obtained for the excited states 21 A1 and 51 A1. It is documented that there exist nonphysical nonstandard solutions that yield energies very close to the physical ones. A simple way of selecting the physically meaningful solutions is proposed. It is demonstrated that the attainability of nonstandard solutions describing a state of H4 within the framework of a given SE-CC method strongly depends on the cluster structure of that state. © 1994 John Wiley & Sons, Inc.
    Additional Material: 7 Tab.
    Type of Medium: Electronic Resource
    Signatur Availability
    BibTip Others were also interested in ...
  • 9
    ISSN: 0020-7608
    Keywords: Computational Chemistry and Molecular Modeling ; Atomic, Molecular and Optical Physics
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Notes: Single-reference coupled-cluster (SR-CC) methods parametrized with respect to four alternative reference-state configurations and orbital sets are applied to the simple H4 model system in which the degree of quasi-degeneracy of the electronic states can be varied in a wide range. Both the ground state and 10 excited states are considered with the aim of numerically studying the attainability and properties of multiple solutions of the system of nonlinear equations for the cluster amplitudes. Comparisons of up to four alternative descriptions of a given state in terms of various solutions of the SR-CC equations are made. It is found that for some excited states different parametrizations yield very close results and that the classification of the solutions into standard and nonstandard ones may not be straightforward. © 1995 John Wiley & Sons, Inc.
    Additional Material: 12 Tab.
    Type of Medium: Electronic Resource
    Signatur Availability
    BibTip Others were also interested in ...
  • 10
    ISSN: 0006-291X
    Source: Elsevier Journal Backfiles on ScienceDirect 1907 - 2002
    Topics: Biology , Chemistry and Pharmacology , Physics
    Type of Medium: Electronic Resource
    Signatur Availability
    BibTip Others were also interested in ...
Close ⊗
This website uses cookies and the analysis tool Matomo. More information can be found here...