Possibility to study eta-mesic nuclei and photoproduction of slow eta-mesons at the GRAAL facility

A new experiment is proposed with the aim to study eta-mesic nuclei and low-energy interactions of eta with nuclei. Two decay modes of eta produced by a photon beam inside a nucleus will be observed, namely a collisional decay \eta N \to \pi N inside the nucleus and the radiative decay \eta \to \gamma \gamma outside. In addition, a collisional decay of stopped S_{11}(1535) resonance inside the nucleus, S_{11}(1535) N \to N N, will be studied. The experiment can be performed using the tagged photon beam at ESRF with the end-point energy 1000 MeV and the GRAAL detector which includes a high-resolution BGO calorimeter and a large acceptance lead-scintillator time-of-flight wall. Some results of simulation and estimates of yields are given.Comment: 20 pages, 19 figure

Electrolyte Hydrodynamics in Anodic Alumina Pores

The electrolyte movement mechanism in the pores of porous anodic alumina under the electric field action during the oxide formation is discussed. A qualitative model for the electrolyte exchange in the growing pore of porous anodic alumina, taking into account the electric field direction and diffuse layer charge, is presented. Since the anodic alumina surface is charged negatively and the electrolyte layer at the pore walls has a positive charge, the electrolyte at the pore walls moves out of the pore under the field. Therefore a reduced-pressure region arises at the pore bottom, resulting in the electrolyte’s movement into the pore through the pore core

Russian authority and the Internet: safety vs freedom of speech

The Internet, in the era of its availability and popularity in modern Russia, plays the most important role both in the dissemination of information and in the daily communications of people. Mass media also use Internet platforms as the main ones in their activities, because traditional forms of media already have a smaller audience coverage, than online-editions. Due to the fact, that in the modern Russia traditional mass media are controlled by the authorities, the Internet remains the last platform, on which independent sources can lead their activities. For today, Internet is the main force, shaping public opinion and trends. In this regard, the current Russian government has a need to develop new measures and introduce new laws to regulate this area. But is it really the primary authority`s task to ensure security within the Russian Internet, or is it driven by the desire to take control of the Internet and restrict its freedom?The main actions of the Russian authorities, taken to ensure the security of the Russian Internet, in chronological order, have been considered and analyzed. Both texts of laws and their real results after adoption have been reviewed and analyzed. For each such action an assessment of public opinion in relation to these innovations has been adduced. The compliance of the stated goals and objectives of the draft laws with their actual results has been considered. The analysis of international assessments of freedom of the mass media, freedom of the Internet and individual freedom in the Russian Federation during various periods of the implementation of these laws in everyday life has been given

Temperature behavior of the magnon modes of the square lattice antiferromagnet

A spin-wave theory of short-range order in the square lattice Heisenberg antiferromagnet is formulated. With growing temperature from T=0 a gapless mode is shown to arise simultaneously with opening a gap in the conventional spin-wave mode. The spectral intensity is redistributed from the latter mode to the former. For low temperatures the theory reproduces results of the modified spin-wave theory by M.Takahashi, J.E.Hirsch et al. and without fitting parameters gives values of observables in good agreement with Monte Carlo results in the temperature range 0 <= T < 0.8J where J is the exchange constant.Comment: 12 pages, 2 figure

Traženje η-mezičkih jezgri fototvorbenim procesima

We present preliminary results of an experiment performed at the 1–GeV electron synchrotron of the Lebedev Physical Institute. Using the bremsstrahlung photon beam with the end-point energy of 650–850 MeV and the carbon target, correlated π +n pairs with opening angle hθπN i = 180◦ and energies hEπ+ i = 300 MeV, hEni = 100 MeV have been observed. They arise from the process γ + 12C → N + η(A − 1) → N + π +n + (A − 2) and provide evidence for the existence of 11 ηB and 11 ηC η-mesic nuclei.Snopovima kočnog zračenja najviše energije 650 i 850 MeV u Lebedevom fizičkom institutu opažale su se vezane tvorbe parova π +n, koji su nastali procesom γ+12C → N + η(A − 1) → N + π +n + (A − 2). Ti su procesi potvrda postojanja 11 ηB i 11 ηC η-mezičkih jezgri

Traženje η-mezičkih jezgri fototvorbenim procesima

We present preliminary results of an experiment performed at the 1–GeV electron synchrotron of the Lebedev Physical Institute. Using the bremsstrahlung photon beam with the end-point energy of 650–850 MeV and the carbon target, correlated π +n pairs with opening angle hθπN i = 180◦ and energies hEπ+ i = 300 MeV, hEni = 100 MeV have been observed. They arise from the process γ + 12C → N + η(A − 1) → N + π +n + (A − 2) and provide evidence for the existence of 11 ηB and 11 ηC η-mesic nuclei.Snopovima kočnog zračenja najviše energije 650 i 850 MeV u Lebedevom fizičkom institutu opažale su se vezane tvorbe parova π +n, koji su nastali procesom γ+12C → N + η(A − 1) → N + π +n + (A − 2). Ti su procesi potvrda postojanja 11 ηB i 11 ηC η-mezičkih jezgri

Pan-squamous genomic profiling stratified by anatomic tumor site and viral association

Background: Squamous cell carcinomas (SCC) have diverse anatomic etiologies but may share common genomic biomarkers. We profiled 7,871 unique SCCs across nine anatomic sites to investigate commonality in genomic alterations (GA), tumor mutational burden (TMB), human papillomavirus (HPV) association, and mutational signatures. Methods: Tissue from over 8,100 unique SCC samples originating from nine anatomic sites (anogenital (anus, cervix, penis, vagina, vulva), esophagus, head and neck, lung, and skin) were sequenced by hybrid capture-based comprehensive genomic profiling to evaluate GA and TMB. About 3% of non-cutaneous SCC samples had UV signatures, indicative of potential primary site misdiagnoses, and were filtered from the analysis. Detection of HPV, including high-risk strains 16, 18, 31, 33, and 45, was implemented through de novo assembly of non-human sequencing reads and BLASTn comparison against all viral nucleotide sequences in the NCBI database. Results: The proportion of HPV+ patients by anatomic site varied, with the highest being anal (91%) and cervical (83%). The mutational landscape of each cohort was similar, regardless of anatomic origin, but clustered based on HPV status. The largest differences in GA frequency as stratified by HPV- vs. HPV+ were TP53 (87% vs. 12%), CDKN2A (45% vs. 6%), and PIK3CA (22% vs. 33%). The median TMB in cases originating from HPV-associated sites was similar, regardless of HPV status. Higher median TMB was observed in lung and skin cases, which exhibited significant enrichment of mutational signatures indicative of tobacco- and UV-induced DNA damage, respectively. Conclusions: HPV+ and HPV- SCC populations have distinct genomic profiles and, for the latter, anatomic site is correlated with TMB distribution, secondary to associated carcinogen exposure. As such, biomarkers such as TMB and UV signature can provide unexpected insight into site of origin misdiagnoses and may correlate with benefit from immune checkpoint inhibitors

Charge and spin density wave ordering transitions in strongly correlated metals

We study the quantum transition from a strongly correlated metal, with heavy fermionic quasiparticles, to a metal with commensurate charge or spin density wave order. To this end, we introduce and numerically analyze a large dimensionality model of Ising spins in a transverse field, coupled to two species of fermions; the analysis borrows heavily from recent progress in the solution of the Hubbard model in large dimensions. At low energies, the Ising order parameter fluctuations are characterized by the critical exponent $z \nu = 1$, while above an energy scale, $\Gamma$, there is a crossover to $z\nu = 1/2$ criticality. We show that $\Gamma$ is of the order of the width of the heavy quasiparticle band, and can be made arbitrarily small for a correlated metal close to a Mott-Hubbard insulator. Therefore, such a correlated metal has a significant intermediate energy range of $z\nu=1/2$ behavior, a single particle spectrum with a narrow quasiparticle band, and well-formed analogs of the lower and upper Hubbard bands; we suggest that these features are intimately related in general.Comment: 14 pages, REVTEX 3.0, 2 postscript figure