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Abstract: We present the concept of a certificate-based proxy decryption (CBPd) system with revocability, which has the following properties: (1) key-escrow freeness; (2) implicit certification; (3) revocability without public key change; and (4) fine-grained delegation. A concrete CBPd scheme is also proposed. The scheme is semantically secure against adaptive chosen plaintext attack (IND-CBPd-Rev-CPA) under the decisional bilinear Diffie-Hellman assumption in the standard model. We also give an enhanced scheme that is secure against adaptive chosen ciphertext attacks (IND-CBPd-Rev-CCA) in the standard model. [Copyright &y& Elsevier]

The African clawed frog, Xenopus laevis, is widely used in biological studies. Ovulation of Xenopus is normally induced by the injection of human chorionic gonadotropin (hCG) into the dorsal lymph sac of fully-grown female frogs. Previously, we reported a novel method for inducing Xenopus ovulation by adding a mixture of steroids into the surrounding water. In the present study, we demonstrate how to induce reproductive behavior in male frogs using the same methodology. The types and concentrations of steroids were evaluated, and the efficiency of the selected steroid for the induction of ejaculation was examined. New procedures were also examined for inducing mating by mixing both females and males activated by steroids. In male frogs, testosterone was effective for the induction of physiological changes, accumulation of melanin in the hands and induction of amplexus. Time course experiments revealed that eight hours were sufficient to induce male reproductive behavior and ovulation in females. Finally, we established an efficient means of inducing pairing in frogs that involved pre-treatment of frogs with salt solution followed by testosterone for males and a mixture of estradiol and progesterone for females. Although the numbers of oocytes obtained were relatively fewer than those resulting from hCG injection, the fertilization rate of eggs ovulated using the new treatment method was similar to that with eggs obtained by hCG-injection, and juveniles developed normally. In conclusion, we have developed a novel method to induce pairing in frogs without the need for injections. [ABSTRACT FROM AUTHOR]

Abstract: In order to simplify certificate management in traditional public key cryptography and solve the key escrow problem in identity-based cryptography, the notion of certificate-based cryptography was introduced. Recently, Ming and Wang proposed a certificate-based signature scheme without pairings. They claimed that the scheme was existentially unforgeable against adaptive chosen message and identity attacks in the random oracle. In this paper, we show that the scheme is insecure against a malicious certifier under existing security model. We also propose a new efficient certificate-based signature scheme without pairings, which is proven secure in the random oracle model. Compared with the existed certificate-based signature schemes without parings, our scheme enjoys shorter signature length and less operation cost. [Copyright &y& Elsevier]

Abstract: We describe the first version (v1.00) of the code hfbrad which solves the Skyrme–Hartree–Fock or Skyrme–Hartree–Fock–Bogolyubov equations in the coordinate representation with spherical symmetry. A realistic representation of the quasiparticle wave functions on the space lattice allows calculations to be performed up to the particle drip lines. Zero-range density-dependent interactions are used in the pairing channel. The pairing energy is calculated by either using a cut-off energy in the quasiparticle spectrum or the regularization scheme proposed by A. Bulgac and Y. Yu. Program summary: Title of the program: hfbrad (v1.00) Catalogue indentifier:ADVM Program summary URL: http://cpc.cs.qub.ac.uk/summaries/ADVM Program obtainable from: CPC Program Library, Queen''s University of Belfast, N. Ireland Licensing provisions: none Computers on which the program has been tested: Pentium-III, Pentium-IV Operating systems: LINUX, Windows Programming language used:FORTRAN-95 Memory required to execute with typical data: 30 MBytes No. of bits in a word: The code is written with a type real and uses the intrinsic function selected_real_kind at the beginning of the code to ask for at least 12 significant digits. This can be easily modified by asking for more significant digits if the architecture of the computer can handle it. No. of processors used:1 Has the code been vectorized?:No No. of bytes in distributed program, including test data, etc.: 40 308 No. of lines in distributed program, including test data, etc.: 5370 Distribution format:tar.gz Nature of physical problem: For a self-consistent description of nuclear pair correlations, both the particle–hole (field) and particle–particle (pairing) channels of the nuclear mean field must be treated within a common approach, which is the Hartree–Fock–Bogolyubov theory. By expressing these fields in spatial coordinates one can obtain the best possible solutions of the problem; however, without assuming specific symmetries the numerical task is often too difficult. This is not the case when the spherical symmetry is assumed, because then the one-dimensional differential equations can be solved very efficiently. Although the spherically symmetric solutions are physically meaningful only for magic and semi-magic nuclei, the possibility of obtaining them within tens of seconds of the CPU makes them a valuable element for studying nuclei across the nuclear chart, including those near or at the drip lines. Method of solution: The program determines the two-component Hartree–Fock–Bogolyubov quasiparticle wave functions on the lattice of equidistant points in the radial coordinate. This is done by solving the eigensystem of two second-order differential equations using the Numerov method. A standard iterative procedure is then used to find self-consistent solutions for the nuclear product wave functions and densities. Restrictions on the complexity of the problem: The main restriction is related to the assumed spherical symmetry. Typical running time: One Hartree–Fock iteration takes about 0.4 s for a medium mass nucleus, convergence is achieved in about 40 s. Unusual features of the program: none [Copyright &y& Elsevier]

Abstract: We describe the program HFBTHO for axially deformed configurational Hartree–Fock–Bogolyubov calculations with Skyrme-forces and zero-range pairing interaction using Harmonic-Oscillator and/or Transformed Harmonic-Oscillator states. The particle-number symmetry is approximately restored using the Lipkin–Nogami prescription, followed by an exact particle number projection after the variation. The program can be used in a variety of applications, including systematic studies of wide ranges of nuclei, both spherical and axially deformed, extending all the way out to nucleon drip lines. Program summary: Title of the program: HFBTHO (v1.66p) Catalogue number: ADUI Program obtainable from: CPC Program Library, Queen''s University of Belfast, N. Ireland Program summary URL: http://cpc.cs.qub.ac.uk/summaries/ADUI Licensing provisions: none Computers on which the program has been tested: Pentium-III, Pentium-IV, AMD-Athlon, IBM Power 3, IBM Power 4, Intel Xeon Operating systems: LINUX, Windows Programming language used: FORTRAN-95 Memory required to execute with typical data: 59 MB when using No. of bits in a word: 64 No. of processors used: 1 Has the code been vectorized?: No No. of bytes in distributed program, including test data, etc.: 195 285 No. of lines in distributed program: 12 058 Distribution format: tar.gz Nature of physical problem: The solution of self-consistent mean-field equations for weakly bound paired nuclei requires a correct description of the asymptotic properties of nuclear quasiparticle wave functions. In the present implementation, this is achieved by using the single-particle wave functions of the Transformed Harmonic Oscillator, which allows for an accurate description of deformation effects and pairing correlations in nuclei arbitrarily close to the particle drip lines. Method of solution: The program uses the axially Transformed Harmonic Oscillator (THO) single-particle basis to expand quasiparticle wave functions. It iteratively diagonalizes the Hartree–Fock–Bogolyubov Hamiltonian based on the Skyrme-forces and zero-range pairing interaction until a self-consistent solution is found. Restrictions on the complexity of the problem: Axial-, time-reversal-, and space-inversion symmetries are assumed. Only quasiparticle vacua of even–even nuclei can be calculated. Typical running time: 4 s per iteration on an Intel Xeon 2.8 GHz processor when using Unusual features of the program: none [Copyright &y& Elsevier]

We describe the new version (v2.08i) of the code HFODD which solves the nuclear Skyrme–Hartree–Fock or Skyrme–Hartree–Fock–Bogolyubov problem by using the Cartesian deformed harmonic-oscillator basis. In the new version, all symmetries can be broken, which allows for calculations with angular frequency and angular momentum tilted with respect to the mass distribution. The new version contains an interface to the LAPACK subroutine ZHPEVX.: Program summaryTitle of the program: HFODD (v2.08i)Catalogue number: ADTOProgram obtainable from: CPC Program Library, Queen''s University of Belfast, N. IrelandProgram summary URL: http://cpc.cs.qub.ac.uk/summaries/ADTOReference in CPC for earlier version of program: J. Dobaczewski and J. Dudek, Comput. Phys. Commun. 131 (2000) 164 (v1.75r)Catalogue number of previous version: ADMLLicensing provisions: noneDoes the new version supersede the previous one: yesComputers on which the program has been tested: SG Power Challenge L, Pentium-II, Pentium-III, AMD-AthlonOperating systems: UNIX, LINUX, Windows-2000Programming language used: FORTRAN-77 and FORTRAN-90Memory required to execute with typical data: 10 MwordsNo. of bits in a word: The code is written in single-precision for the use on a 64-bit processor. The compiler option -r8 or +autodblpad (or equivalent) has to be used to promote all real and complex single-precision floating-point items to double precision when the code is used on a 32-bit machine.Has the code been vectorised?: YesNo. of bytes in distributed program, including test data, etc.: 265352No. of lines in distributed program: 52656Distribution format: tar gzip fileNature of physical problem: The nuclear mean-field and an analysis of its symmetries in realistic cases are the main ingredients of a description of nuclear states. Within the Local Density Approximation, or for a zero-range velocity-dependent Skyrme interaction, the nuclear mean-field is local and velocity dependent. The locality allows for an effective and fast solution of the self-consistent Hartree–Fock equations, even for heavy nuclei, and for various nucleonic (n-particle n-hole) configurations, deformations, excitation energies, or angular momenta. Similar Local Density Approximation in the particle-particle channel, which is equivalent to using a zero-range interaction, allows for a simple implementation of pairing effects within the Hartree–Fock–Bogolyubov method.Method of solution: The program uses the Cartesian harmonic oscillator basis to expand single-particle or single-quasiparticle wave functions of neutrons and protons interacting by means of the Skyrme effective interaction and zero-range pairing interaction. The expansion coefficients are determined by the iterative diagonalization of the mean field Hamiltonians or Routhians which depend non-linearly on the local neutron and proton densities. Suitable constraints are used to obtain states corresponding to a given configuration, deformation or angular momentum. The method of solution has been presented in: J. Dobaczewski, J. Dudek, Comput. Phys. Commun. 102 (1997) 166.Summary of revisions:

The explanation could even be used to make vegetables more appealing. [ABSTRACT FROM AUTHOR]

Abstract: We describe the new version (v2.08k) of the code HFODD which solves the nuclear Skyrme–Hartree–Fock or Skyrme–Hartree–Fock–Bogolyubov problem by using the Cartesian deformed harmonic-oscillator basis. Similarly as in the previous version (v2.08i), all symmetries can be broken, which allows for calculations with angular frequency and angular momentum tilted with respect to the mass distribution. In the new version, three minor errors have been corrected. New Version Program Summary: Title of program: HFODD; version: 2.08k Catalogue number: ADVA Catalogue number of previous version: ADTO (Comput. Phys. Comm. 158 (2004) 158) Program summary URL: http://cpc.cs.qub.ac.uk/summaries/ADVA Program obtainable from: CPC Program Library, Queen''s University of Belfast, N. Ireland Does the new version supersede the previous one: yes Computers on which this or another recent version has been tested: SG Power Challenge L, Pentium-II, Pentium-III, AMD-Athlon Operating systems under which the program has been tested: UNIX, LINUX, Windows-2000 Programming language used: Fortran Memory required to execute with typical data: 10M words No. of bits in a word: 64 No. of lines in distributed program, including test data, etc.: 52 631 No. of bytes in distributed program, including test data, etc.: 266 885 Distribution format:tar.gz Nature of physical problem: The nuclear mean-field and an analysis of its symmetries in realistic cases are the main ingredients of a description of nuclear states. Within the Local Density Approximation, or for a zero-range velocity-dependent Skyrme interaction, the nuclear mean-field is local and velocity dependent. The locality allows for an effective and fast solution of the self-consistent Hartree–Fock equations, even for heavy nuclei, and for various nucleonic (n-particle n-hole) configurations, deformations, excitation energies, or angular momenta. Similar Local Density Approximation in the particle–particle channel, which is equivalent to using a zero-range interaction, allows for a simple implementation of pairing effects within the Hartree–Fock–Bogolyubov method. Solution method: The program uses the Cartesian harmonic-oscillator basis to expand single-particle or single-quasiparticle wave functions of neutrons and protons interacting by means of the Skyrme effective interaction and zero-range pairing interaction. The expansion coefficients are determined by the iterative diagonalization of the mean field Hamiltonians or Routhians which depend non-linearly on the local neutron and proton densities. Suitable constrains are used to obtain states corresponding to a given configuration, deformation or angular momentum. The method of solution has been presented in [J. Dobaczewski, J. Dudek, Comput. Phys. Comm. 102 (1997) 166]. Summary of revisions: 1. Incorrect value of the “” force parameter for SLY5 has been corrected. 2. Opening of an empty file “FILREC” for IWRIRE=−1 has been removed. 3. Call to subroutine “OLSTOR” has been moved before that to “SPZERO”. In this way, correct data transferred to “FLISIG”, “FLISIM”, “FLISIQ” or “FLISIZ” allow for a correct determination of the candidate states for diabatic blocking. These corrections pertain to the user interface of the code and do not affect results performed for forces other than SLY5. Restrictions on the complexity of the problem: The main restriction is the CPU time required for calculations of heavy deformed nuclei and for a given precision required. Pairing correlations are only included for even–even nuclei and conserved simplex symmetry. Unusual features: The user must have access to the NAGLIB subroutine F02AXE or to the LAPACK subroutines ZHPEV or ZHPEVX, which diagonalize complex Hermitian matrices, or provide another subroutine which can perform such a task. The LAPACK subroutines ZHPEV and ZHPEVX can be obtained from the Netlib Repository at University of Tennessee, Knoxville: http://netlib2.cs.utk.edu/cgi-bin/netlibfiles.pl?filename=/lapack/complex16/zhpev.f and http://netlib2.cs.utk.edu/cgi-bin/netlibfiles.pl?filename=/lapack/complex16/zhpevx.f, respectively. The code is written in single-precision for use on a 64-bit processor. The compiler option -r8 or +autodblpad (or equivalent) has to be used to promote all real and complex single-precision floating-point items to double precision when the code is used on a 32-bit machine. Typical running time: One Hartree–Fock iteration for the superdeformed, rotating, parity conserving state of 152 66Dy86 takes about six seconds on the AMD-Athlon 1600+ processor. Starting from the Woods–Saxon wave functions, about fifty iterations are required to obtain the energy converged within the precision of about 0.1 keV. In the case when every value of the angular velocity is converged separately, the complete superdeformed band with precisely determined dynamical moments can be obtained within forty minutes of CPU on the AMD-Athlon 1600+ processor. This time can be often reduced by a factor of three when a self-consistent solution for a given rotational frequency is used as a starting point for a neighboring rotational frequency. Additional comments: The actual output files obtained during user''s test runs may differ from those provided in the distribution file. The differences may occur because various compilers may produce different results in the following aspects: [(a)] The initial Nilsson spectrum (the starting point of each run) is Kramers degenerate, and thus the diagonalization routine may return the degenerate states in arbitrary order and in arbitrary mixture. For an odd number of particles, one of these states becomes occupied, and the other one is left empty. Therefore, starting points of such runs can widely vary from compiler to compiler, and these differences cannot be controlled. [(b)] For axial shapes, two quadrupole moments (with respect to two different axes) become very small and their values reflect only a numerical noise. However, depending on which of these two moments is smaller, the intrinsic-frame Euler axes will differ, most often by 180 degrees. Hence, signs of some moments and angular momenta may vary from compiler to compiler, and these differences cannot be controlled. These differences are insignificant. The final energies do not depend on them, although the intermediate results can. [Copyright &y& Elsevier]

We observed the reproductive behavior of the oval squid Sepioteuthis lessoniana in captivity. The male used three different mating behaviors: male-parallel (MP), male-upturned (MU) and sneaking. Male competition over females frequently occurred before and during the female egg-laying period, and the outcome of most fights depended on male body size. Larger males guarded their partners from other males and performed MP mating during the egg-laying period of the paired females. In contrast, there was no pairing and mate guarding in MU mating and sneaking, which were adopted by smaller subordinate males as alternative tactics outside female egg-laying period and during the period, respectively. MP matings were 95% successful, but more than half of MU matings were unsuccessful. Higher mating success in MP mating was achieved through pairing, whereas males in MU mating were less successful because mating attempts without pair formation were often foiled by escape of the female. Sneaking was successful in all cases but occurred less frequently. Spermatophores were attached at the opening of the oviduct in MP mating, whereas they were attached around the female buccal membrane in MU mating and sneaking. Considering the route of egg transportation, higher fertilization success can be expected in MP mating because of the advantageous location of the attached spermatophores. Our results suggest that MP mating is used by larger, paired males during the female egg-laying period, and that MU mating and sneaking are alternative tactics adopted by smaller, subordinate males. These alternative mating behaviors would be conditional strategy dependent on relative body size, because some individual males displayed both MP and MU mating behaviors. [ABSTRACT FROM AUTHOR]