Coordination pattern adaptability: energy cost of degenerate behaviors.

This study investigated behavioral adaptability, which could be defined as a blend between stability and flexibility of the limbs movement and their inter-limb coordination, when individuals received informational constraints. Seven expert breaststroke swimmers performed three 200-m in breaststroke at constant submaximal intensity. Each trial was performed randomly in a different coordination pattern: 'freely-chosen', 'maximal glide' and 'minimal glide'. Two underwater and four aerial cameras enabled 3D movement analysis in order to assess elbow and knee angles, elbow-knee pair coordination, intra-cyclic velocity variations of the center of mass, stroke rate and stroke length and inter-limb coordination. The energy cost of locomotion was calculated from gas exchanges and blood lactate concentration. The results showed significantly higher glide, intra-cyclic velocity variations and energy cost under 'maximal glide' compared to 'freely-chosen' instructional conditions, as well as higher reorganization of limb movement and inter-limb coordination (p<0.05). In the 'minimal glide' condition, the swimmers did not show significantly shorter glide and lower energy cost, but they exhibited significantly lower deceleration of the center of mass, as well as modified limb movement and inter-limb coordination (p<0.05). These results highlight that a variety of structural adaptations can functionally satisfy the task-goal

Symmetry, singularities and integrability in complex dynamics III: approximate symmetries and invariants

The different natures of approximate symmetries and their corresponding first integrals/invariants are delineated in the contexts of both Lie symmetries of ordinary differential equations and Noether symmetries of the Action Integral. Particular note is taken of the effect of taking higher orders of the perturbation parameter. Approximate symmetries of approximate first integrals/invariants and the problems of calculating them using the Lie method are considered

West Nile virus in the New World: potential impacts on bird species

The past five years have seen the arrival and extremely rapid expansion of West Nile virus (WNV) in the Western Hemisphere. The rapid sweep across North America has permitted little time for developing knowledge of the virus’s potential impacts on wildlife in the New World. Given this information gap, we here summarize for the ornithological community what is known or can be anticipated for WNV’s effect on bird communities in coming years. Our particular focus is on impacts of WNV on the conservation status of birds, the principal vertebrate reservoir for the virus

Serological methods in modern biotechnologies and their bioanalytical standardization

Серологічні методи використовувались в першу чергу перед усіма методами клінічної лабораторної діагностики, і вони залишаються надзвичайно актуальними і донині. Серологічні методи застосовуються для діагностики як інфекційних (бактеріальних, вірусних, грибкових, паразитарних), так і неінфекційних (онкологічних, ендокринних, алергічних) захворювань. Значна частка діагностичних обстежень, проведених лабораторною службою, стосується саме серологічних тестів. Серологічні методи залишаються невід'ємною частиною забезпечення санітарного та епідеміологічного благополуччя кожної країни. Розробка продуктів серологічної діагностики є предметом імунобіотехнології – розділу біотехнології, метою якого є створення діагностичних та імунних препаратів для діагностики, лікування та профілактики захворювань людини та тварин. Продукти для серологічної діагностики належать до класу медичних апаратів. Очевидно, що проблема, вирішена такими медичними препаратами, є надзвичайно важливою, адже від вірогідності результатів лабораторного дослідження залежить здоров’я та життя пацієнта. Ось чому на сучасному етапі особлива увага приділяється якості медичних пристроїв для діагностики in vitro, що, в свою чергу, пов'язано з питаннями стандартизації та технічного регулювання. У роботі здійснено огляд медикобіологічних характеристик основних поширених серологічних методів діагностики. Узагальнено сучасні наукові та нормативні вимоги до аналітичної якості продукції для серологічної діагностики in vitro.Serological methods have become to use first turn before all methods of clinical laboratory diagnostics, and they stay remain extremely relevant to the present day. Serologic methods are used for diagnostics as infectious (bacterial, viral, fungal, parasitic), and non-infectious (oncological, endocrine, allergic) diseases. A significant proportion of diagnostic examinations carried out by the laboratory service relates precisely to serological tests. Serologic methods remain an indispensable part of ensuring the sanitary and epidemiological well-being of each country. Development of serological diagnostics products is the subject of immunobiotechnology – a section of biotechnology, which aims to create diagnostic and immune preparations for the diagnosis, treatment and prevention of human and animal diseases. Products for serological diagnostics belong to a class of medical devises. Obviously, the problem solved by such medical products is extremely responsible, because the health and life of the patient depends on the correctness of the outcome of the laboratory study. That is why, at the present stage, special attention is paid to the quality of medical devises for in vitro diagnostics, which, in turn, is connected with questions of standardization and technical regulation. A review of the medical and biological characteristics of the main common serological methods of diagnosis was made. The modern scientific and regulatory requirements for the analytical quality of products for serological in vitro diagnostics were summarized

Consequences of a covariant Description of Heavy Ion Reactions at intermediate Energies

Heavy ion collisions at intermediate energies are studied by using a new RQMD code, which is a covariant generalization of the QMD approach. We show that this new implementation is able to produce the same results in the nonrelativistic limit (i.e. 50MeV/nucl.) as the non-covariant QMD. Such a comparison is not available in the literature. At higher energies (i.e. 1.5 GeV/nucl. and 2 GeV/nucl.) RQMD and QMD give different results in respect to the time evolution of the phase space, for example for the directed transverse flow. These differences show that consequences of a covariant description of heavy ion reactions within the framework of RQMD are existing even at intermediate energies.Comment: LaTex-file, 28 pages, 8 figures (available upon request), accepted for publication in Physical Review

Optimizing Parking Orbits for Roundtrip Mars Missions

A roundtrip Mars mission presents many challenges to the design of a transportation system and requires a series of orbital maneuvers within Mars vicinity to capture, reorient, and then return the spacecraft back to Earth. The selection of a Mars parking orbit is crucial to the mission design; not only can the parking or-bit choice drastically impact the V requirements of these maneuvers but also it must be properly aligned to target desired surface or orbital destinations. This paper presents a method that can optimize the Mars parking orbits given the arrival and departure conditions from heliocentric trajectories, and it can also en-force constraints on the parking orbits to satisfy other architecture design requirements such as co-planar subperiapsis descent to planned landing sites, due east or co-planar ascent back to the parking orbit, or low cost transfers to and from Phobos and Deimos

Quantum Time and Spatial Localization: An Analysis of the Hegerfeldt Paradox

Two related problems in relativistic quantum mechanics, the apparent superluminal propagation of initially localized particles and dependence of spatial localization on the motion of the observer, are analyzed in the context of Dirac's theory of constraints. A parametrization invariant formulation is obtained by introducing time and energy operators for the relativistic particle and then treating the Klein-Gordon equation as a constraint. The standard, physical Hilbert space is recovered, via integration over proper time, from an augmented Hilbert space wherein time and energy are dynamical variables. It is shown that the Newton-Wigner position operator, being in this description a constant of motion, acts on states in the augmented space. States with strictly positive energy are non-local in time; consequently, position measurements receive contributions from states representing the particle's position at many times. Apparent superluminal propagation is explained by noting that, as the particle is potentially in the past (or future) of the assumed initial place and time of localization, it has time to propagate to distant regions without exceeding the speed of light. An inequality is proven showing the Hegerfeldt paradox to be completely accounted for by the hypotheses of subluminal propagation from a set of initial space-time points determined by the quantum time distribution arising from the positivity of the system's energy. Spatial localization can nevertheless occur through quantum interference between states representing the particle at different times. The non-locality of the same system to a moving observer is due to Lorentz rotation of spatial axes out of the interference minimum.Comment: This paper is identical to the version appearing in J. Math. Phys. 41; 6093 (Sept. 2000). The published version will be found at http://ojps.aip.org/jmp/. The paper (40 page PDF file) has been completely revised since the last posting to this archiv

Time and Dirac Observables in Friedmann Cosmologies

A cosmological time variable is emerged from the Hamiltonian formulation of Friedmann model to measure the evolution of dynamical observables in the theory. A set of observables has been identified for the theory on the null hypersurfaces that its evolution is with respect to the volume clock introduced by the cosmological time variable.Comment: 11 page

Quasi-tracking solar active regimes with radio telescope ratan-600 and the construction of two-dimensional radio maps of the sun

We discuss the results of the radio telescope RATAN-600 by “zoned relay” using the conical secondary reflector. Such observations permit the evolution of the radio emission of local solar sources to be studied as well as the construction of the two-dimensional images of the Sun