There are no statistically significant differences in personality traits between people who claimed that they would and those that would not be willing to become sperm donors. It is possible that some other factors (e.g. cultural values) influence the decision to become sperm donor, but personality traits play an important role in making decisions regarding sperm donation process, possible receivers of donation and relations between the donor and his biological offspring.

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The current paper proposes a model for describing mechanical phenomena that occur during the process of mammal fertilization when spermatozoa impact the surface of Zona Pellucida. Zona pellucida (ZP) is a dynamical 3D matrix that surrounds the mammalian oocyte. In the process of fertilization, sperm cell has to penetrate this structure. To describe impact of sperm cells with velocities that are effective and those that are ineffective relative to the oscillatory behavior of ZP, the discreet continuum model in the form of spherical net model is used. Resultant trajectories of knot mass particles dynamics of mouse ZP spherical net model in the form of generalized Lussajous curves are presented. Using generalized Lussajous curves, parametric frequency analysis of oscillatory behavior of knot material particles in the mouse ZP spherical net model is conducted. The influence of impact angles of sperm cells on corresponding knot mass particle trajectory is discussed. Favorable and unfavorable trajectories of knot mass particle motions are discussed in the context of successful fertilization.

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Using Mihailo Petrović's theory of mathematical phenomenology elements, phenomenological mapping in vibrations, signals, resonance and dynamical absorptions in models of dynamics of chain systems -the abstractions of different real dynamics of a chain system are identified and presented. Using a mathematical description of a chain mechanical system with a finite number of mass particles coupled by linear elastic springs and a finite number of degrees of freedom expressed by corresponding generalized independent coordinates, translator displacements and corresponding analysis of solutions for a free and forced vibrations series of multi-frequency regimes and resonant states as well as dynamical absorption states are identified. Using mathematical analogy and phenomenological mapping, analyses of the dynamics of other chain models are made. Phenomenological mapping is used to explain dynamics in systems with multiple deformable bodies (beams, plates, membranes or belts) through resonance and dynamical absorptions in the system and transfer of mechanical energies between bodies. Amplitude-frequency graphs for homogeneous and non-homogeneous chain systems are presented for a system with 11 degrees of freedom. Expressions for generalized coordinates of a chain nonhomogeneous system in resonance regimes for a general case are derived. A theorem is defined and proven.