Search for fourth generation quarks and leptons at the Fermilab Tevatron and CERN Large Hadron Collider

If next generations of heavy quarks and leptons exist within the standard model (SM), they can manifest themselves in Higgs boson production at the Tevatron and the LHC, before being actually observed. This generation leads to an increase of the Higgs boson production cross section via gluon fusion at hadron colliders by a factor 6-9. So, the study of this process at the Tevatron and LHC can finally fix the number of generations in the SM. Using the $WW^*$ Higgs boson decay channel, the studies at the upgraded Tevatron will answer the question about the next generation for mass values 135 GeV \lsim M_H\lsim 190 GeV. Studying the $\tau\bar{\tau}$ channel we show its large potential for the study of the Higgs boson at the LHC even in the standard case of three generations. At the Tevatron, studies in this channel could explore the mass range 110-140 GeV.Comment: 13 pages, 4 figures, LaTeX/RevTeX, final version accepted for publicatio

Gravitomagnetic Effects in the Propagation of Electromagnetic Waves in Variable Gravitational Fields of Arbitrary-Moving and Spinning Bodies

Propagation of light in the gravitational field of self-gravitating spinning bodies moving with arbitrary velocities is discussed. The gravitational field is assumed to be "weak" everywhere. Equations of motion of a light ray are solved in the first post-Minkowskian approximation that is linear with respect to the universal gravitational constant $G$. We do not restrict ourselves with the approximation of gravitational lens so that the solution of light geodesics is applicable for arbitrary locations of source of light and observer. This formalism is applied for studying corrections to the Shapiro time delay in binary pulsars caused by the rotation of pulsar and its companion. We also derive the correction to the light deflection angle caused by rotation of gravitating bodies in the solar system (Sun, planets) or a gravitational lens. The gravitational shift of frequency due to the combined translational and rotational motions of light-ray-deflecting bodies is analyzed as well. We give a general derivation of the formula describing the relativistic rotation of the plane of polarization of electromagnetic waves (Skrotskii effect). This formula is valid for arbitrary translational and rotational motion of gravitating bodies and greatly extends the results of previous researchers. Finally, we discuss the Skrotskii effect for gravitational waves emitted by localized sources such as a binary system. The theoretical results of this paper can be applied for studying various relativistic effects in microarcsecond space astrometry and developing corresponding algorithms for data processing in space astrometric missions such as FAME, SIM, and GAIA.Comment: 36 pages, 1 figure, submitted to Phys. Rev.

New hadrons as ultra-high energy cosmic rays

Ultra-high energy cosmic ray (UHECR) protons produced by uniformly distributed astrophysical sources contradict the energy spectrum measured by both the AGASA and HiRes experiments, assuming the small scale clustering of UHECR observed by AGASA is caused by point-like sources. In that case, the small number of sources leads to a sharp exponential cutoff at the energy E<10^{20} eV in the UHECR spectrum. New hadrons with mass 1.5-3 GeV can solve this cutoff problem. For the first time we discuss the production of such hadrons in proton collisions with infrared/optical photons in astrophysical sources. This production mechanism, in contrast to proton-proton collisions, requires the acceleration of protons only to energies E<10^{21} eV. The diffuse gamma-ray and neutrino fluxes in this model obey all existing experimental limits. We predict large UHE neutrino fluxes well above the sensitivity of the next generation of high-energy neutrino experiments. As an example we study hadrons containing a light bottom squark. These models can be tested by accelerator experiments, UHECR observatories and neutrino telescopes.Comment: 17 pages, revtex style; v2: shortened, as to appear in PR

Differential response to pallidal deep brain stimulation among monogenic dystonias: systematic review and meta-analysis

ObjectiveGenetic subtypes of dystonia may respond differentially to deep brain stimulation of the globus pallidus pars interna (GPi DBS). We sought to compare GPi DBS outcomes among the most common monogenic dystonias.MethodsThis systematic review and meta-analysis followed the Preferred Reporting Items for Systematic Reviews and Meta-analyses and Meta-analysis of Observational Studies in Epidemiology guidelines. We searched PubMed for studies on genetically confirmed monogenic dystonia treated with GPi DBS documenting pre-surgical and post-surgical assessments using the Burke-Fahn-Marsden Dystonia Rating Scale Motor Score (BFMMS) and Burke-Fahn-Marsden Disability Score (BFMDS). We performed (i) meta-analysis for each gene mutation; (ii) weighted ordinary linear regression analyses to compare BFMMS and BFMDS outcomes between DYT-TOR1A and other monogenic dystonias, adjusting for age and disease duration and (iii) weighted linear regression analysis to estimate the effect of age, sex and disease duration on GPi DBS outcomes. Results were summarised with mean change and 95% CI.ResultsDYT-TOR1A (68%, 38.4 points; p<0.001), DYT-THAP1 (37% 14.5 points; p<0.001) and NBIA/DYT-PANK2 (27%, 21.4 points; p<0.001) improved in BFMMS; only DYT-TOR1A improved in BFMDS (69%, 9.7 points; p<0.001). Improvement in DYT-TOR1A was significantly greater than in DYT-THAP1 (BFMMS -31%), NBIA/DYT-PANK2 (BFMMS -35%; BFMDS -53%) and CHOR/DYT-ADCY5 (BFMMS -36%; BFMDS -42%). Worse motor outcomes were associated with longer dystonia duration and older age at dystonia onset in DYT-TOR1A, longer dystonia duration in DYT/PARK-TAF1 and younger age at dystonia onset in DYT-SGCE.ConclusionsGPi DBS outcomes vary across monogenic dystonias. These data serve to inform patient selection and prognostic counselling

Two-Loop O(alpha_s G_F M_Q^2) Heavy-Quark Corrections to the Interactions between Higgs and Intermediate Bosons

By means of a low-energy theorem, we analyze at O(alpha_s G_F M_Q^2) the shifts in the Standard-Model W^+W^-H and ZZH couplings induced by virtual high-mass quarks, Q, with M_Q >> M_Z, M_H, which includes the top quark. Invoking the improved Born approximation, we then find the corresponding corrections to various four- and five-point Higgs-boson production and decay processes which involve the W^+W^-H and ZZH vertices with one or both of the gauge bosons being connected to light-fermion currents, respectively. This includes e^+e^- -> f anti-f H via Higgs-strahlung, via W^+W^- fusion (with f = nu_e), and via ZZ fusion (with f = e), as well as H -> 2V -> 4f (with V = W, Z).Comment: 20 pages (Latex); Physical Review D (to appear

Synaptic processes and immune-related pathways implicated in Tourette syndrome.

Tourette syndrome (TS) is a neuropsychiatric disorder of complex genetic architecture involving multiple interacting genes. Here, we sought to elucidate the pathways that underlie the neurobiology of the disorder through genome-wide analysis. We analyzed genome-wide genotypic data of 3581 individuals with TS and 7682 ancestry-matched controls and investigated associations of TS with sets of genes that are expressed in particular cell types and operate in specific neuronal and glial functions. We employed a self-contained, set-based association method (SBA) as well as a competitive gene set method (MAGMA) using individual-level genotype data to perform a comprehensive investigation of the biological background of TS. Our SBA analysis identified three significant gene sets after Bonferroni correction, implicating ligand-gated ion channel signaling, lymphocytic, and cell adhesion and transsynaptic signaling processes. MAGMA analysis further supported the involvement of the cell adhesion and trans-synaptic signaling gene set. The lymphocytic gene set was driven by variants in FLT3, raising an intriguing hypothesis for the involvement of a neuroinflammatory element in TS pathogenesis. The indications of involvement of ligand-gated ion channel signaling reinforce the role of GABA in TS, while the association of cell adhesion and trans-synaptic signaling gene set provides additional support for the role of adhesion molecules in neuropsychiatric disorders. This study reinforces previous findings but also provides new insights into the neurobiology of TS

A Kinematical Approach to Conformal Cosmology

We present an alternative cosmology based on conformal gravity, as originally introduced by H. Weyl and recently revisited by P. Mannheim and D. Kazanas. Unlike past similar attempts our approach is a purely kinematical application of the conformal symmetry to the Universe, through a critical reanalysis of fundamental astrophysical observations, such as the cosmological redshift and others. As a result of this novel approach we obtain a closed-form expression for the cosmic scale factor R(t) and a revised interpretation of the space-time coordinates usually employed in cosmology. New fundamental cosmological parameters are introduced and evaluated. This emerging new cosmology does not seem to possess any of the controversial features of the current standard model, such as the presence of dark matter, dark energy or of a cosmological constant, the existence of the horizon problem or of an inflationary phase. Comparing our results with current conformal cosmologies in the literature, we note that our kinematic cosmology is equivalent to conformal gravity with a cosmological constant at late (or early) cosmological times. The cosmic scale factor and the evolution of the Universe are described in terms of several dimensionless quantities, among which a new cosmological variable delta emerges as a natural cosmic time. The mathematical connections between all these quantities are described in details and a relationship is established with the original kinematic cosmology by L. Infeld and A. Schild. The mathematical foundations of our kinematical conformal cosmology will need to be checked against current astrophysical experimental data, before this new model can become a viable alternative to the standard theory.Comment: Improved version, with minor changes. 58 pages, including 7 figures and one table. Accepted for publication in General Relativity and Gravitation (GERG

A New Day: The Role of Telemedicine in Reshaping Care for Persons With Movement Disorders

Contains fulltext : 229724.pdf (Publisher’s version ) (Closed access)The COVID-19 pandemic has demonstrated the fragility of clinic-based care for Parkinson's disease and other movement disorders. In response to the virus, many clinics across the world abruptly closed their doors to persons with Parkinson's disease. Fortunately, a niche care model, telemedicine-first described in this journal a generation ago-emerged as the dominant means of providing care. As we adjust to a new normal, we should focus future care not on clinics but on patients. Their needs, guided by clinicians, should determine how care is delivered, whether in the clinic, at home, remotely, or by some combination. Within this patient-centered approach, telemedicine is an attractive care option but not a complete replacement for in-person consultations, which are valuable for specific problems and for those who have access. Now that many clinicians and patients have gained exposure to telemedicine, we can better appreciate its advantages (eg, convenience) and disadvantages (eg, restricted examination). We can also create a new future that utilizes the Internet, video conferencing, smartphones, and sensors. This future will bring many clinicians to one patient, connect individual experts to countless patients, use widely available devices to facilitate diagnosis, and apply novel technologies to measure the disease in new ways. These approaches, which extend to education and research, enable a future where we can care for anyone anywhere and will help us stem the tide of Parkinson's disease. © 2020 International Parkinson and Movement Disorder Society