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In the multiscalar-metric frameworks, the issues of the vacuum energy/cosmological constant (CC) screening due to the Weyl-scale enhancement of the Diff gauge symmetry, along with emergence of the massive dark gravity components through the gravitational Higgs mechanism are considered. A generic dark gravity model is developed, with the two extreme versions of the model of particular interest based on General Relativity (GR) and its classically equivalent Weyl transverse alternative being compared and argued to be, generally, inequivalent. The so constructed spontaneously broken Weyl Transverse Relativity (WTR) is proposed as a viable beyond-GR effective field theory of gravity, with screening of the Lagrangian CC, superseded by the induced one, and emergence of the massive tensor and scalar gravitons as the dark gravity components. A basic concept with the spontaneously broken Diff gauge symmetry/relativity -- in particular, WTR vs. GR -- as a principle source of the emergent dark gravity components of the Universe is put forward., Comment: 15 pages. Extended version. References added. The main content unchanged

In the frameworks of the effective field theory of metric supplemented by some distinct dynamical coordinates parametrized, in turn, by a scalar quartet -- the so-called quartet-metric gravity -- the extension of tensor gravity through a massive scalar graviton in addition to the massless tensor one is consistently exposed. The field equations for the two realizations of such an extension originating from the classically equivalent prototype theories - General Relativity (GR) and its Weyl transverse (WTDiff) alternative - are derived and argued to be, generally, non-equivalent, with the pure-gravity case manifesting this explicitly in detail. A splitting of the cosmological constant onto the gravitating and non-gravitating parts, with a partial screening of the vacuum energy through an emergent scalar-graviton dark substance, is considered. A prior importance of treating the WTDiff gravity as a prototype one on par with GR, when looking for a putative next-to-GR extended theory of gravity with a scalar-graviton dark substance, is stressed., Comment: 18 pages

In the general frameworks of an earlier introduced quartet-metric/multi-component gravity, a theory of a massive scalar graviton supplementing the massless tensor one is consistently deduced. The peculiarities of the scalar-graviton field compared to the canonical scalar one are demonstrated. The light scalar graviton is treated as an emergent dark substance of the Universe: dark matter and/or dark energy depending on the solution. The case with scalar graviton as dark energy responsible for the late-time accelerated expansion of the Universe is studied in more detail. In particular, it is shown that due to an attractor solution for the light scalar graviton there naturally emerges at the classical level a tiny nonzero effective cosmological constant, even in the absence of the Lagrangian one. The prospects of going beyond LCDM model per scalar graviton are shortly indicated., Comment: 16 pages, 2 figures. Minor revision, references added

As a group-theoretic foundation of gravity, it is considered an affine-Goldstone nonlinear model based upon the nonlinear realization of the global affine symmetry spontaneously broken at the Planck scale to the Poincare symmetry. It is shown that below this scale the model justifies and elaborates an earlier introduced effective field theory of the quartet-metric gravity incorporating the gravitational dark substances emerging in addition to the tensor graviton. The prospects for subsequent going beyond the nonlinear model above the Planck scale are indicated., Comment: 17 pages. Slightly modified and abriged version. Content unchanged

Preclinical magnetic resonance imaging often requires the entire body of an animal to be imaged with sufficient quality. This is usually performed by combining regions scanned with small coils with high sensitivity or long scans using large coils with low sensitivity. Here, a metamaterial-inspired design employing of a parallel array of wires operating on the principle of eigenmode hybridization is used to produce a small animal whole-body imaging coil. The coil field distribution responsible for the coil field of view and sensitivity is simulated in an electromagnetic simulation package and the coil geometrical parameters are optimized for the chosen application. A prototype coil is then manufactured and assembled using brass telescopic tubes and copper plates as distributed capacitance, its field distribution is measured experimentally using B1+ mapping technique and found to be in close correspondence with simulated results. The coil field distribution is found to be suitable for whole-body small animal imaging and coil image quality is compared with a number of commercially available coils by whole-body living mice scanning. Signal to noise measurements in living mice show outstanding coil performance compared to commercially available coils with large receptive fields, and rivaling performance compared to small receptive field and high-sensitivity coils. The coil is deemed suitable for whole-body small animal preclinical applications., Comment: 11 pages, 6 figures, 2 tables

In the framework of the minimal quartet-metric gravity/systogravity, a scalar graviton/systolon is stated as a universal dark component, with supplementary manifestations in the different contexts either as dark matter or dark energy. An ensuing extension to the standard {\Lambda}CDM model is developed. A modification of the late expansion of the Universe, with an attractor of a scalar master equation defining an effective cosmological constant, which supersedes the true one, is proposed. A new partial solution to the cosmological constant problem is discussed., Comment: 11 pages

General Relativity extended through a dynamical scalar quartet is proposed as a theory of the scalar-vector-tensor gravity, generically describing the unified gravitational dark matter (DM) and dark energy (DE). The implementation in the weak-field limit of the Higgs mechanism for the gravity, with a redefinition of metric field, is exposed in a generally covariant form. Under a natural restriction on parameters, the redefined theory possesses in the linearized approximation by a residual transverse-diffeomorphism invariance, and consistently comprises the massless tensor graviton and a massive scalar one as a DM particle. A number of the adjustable parameters in the full nonlinear theory and a partial decoupling of the latter from its weak-field limit noticeably extend the perspectives for the unified description of the gravity DM and DE in the various phenomena at the different scales., Comment: 17 pages

In the framework of the unified compositeness of leptons, quarks and Higgs bosons, the hidden local symmetry \hat H_{loc}= SU(2)_L\times U(1)_Y with the heavy composite vector bosons, in addition to the SM gauge bosons, is briefly described. Supplementary hypothesis of the vector boson dominance (VBD) of the SM gauge interactions is considered. It is argued that this should produce the universal dominant residual interactions of the SM composite particles, i.e., all of the fermions and Higgs bosons. Restrictions on the universal residual fermion-fermion, fermion-boson and boson-boson interactions due to the VBD are investigated. Manifestations of the residual interactions at the 4 TeV mu+mu- collider are studied. It is shown that at 95% C.L. the unified substructure could be investigated at the collider in the processes mu+mu- \to \bar ff up to the compositeness scale O(150 TeV), in the processes mu+mu- \to ZH, W+W- up to O(100 TeV) and in the process mu+mu- \to ZHH up to O(40 TeV), which lie in the naturally preferable Deca-TeV region., Comment: 10 pages, LaTeX, 4 PostScript figures, Presented by Yu. F. Pirogov at the International Workshop on Linac-Ring Tipe ep and gamma p Colliders, 9-11 April 1997, Ankara. A note and several references are added

The unified compositeness of leptons, quarks and Higgs bosons is proposed as a possible scenario for New Physics beyond the Standard Model. The following topics of the scenario are briefly discussed: - Chiral gauge exceptional symmetry E_6 as a strong internal binding mechanism; - Higgs doublet as a composite Goldstone boson; - Nonlinear Standard Model as a prototype ``low energy'' effective field theory of the unified compositeness; - Hidden local symmetry and an improved ``low energy'' effective field theory of the unified compositeness; - Heavy composite vector bosons and vector boson dominance of the SM gauge interactions; - Universal dominant residual interactions as a signature of the unified compositeness; - Manifestations of the residual interactions and potential of the future TeV e^+e^- linear colliders to uncover the unified compositeness., Comment: 22 pages, LaTeX, 2 Postscript figures, submitted to the 28th Int. Conf. on High Energy Physics, 25-31 July 1996, Warsaw, Poland