No observational constraints from hypothetical collisions of hypothetical dark halo primordial black holes with galactic objects

It was suggested by several authors that hypothetical primordial black holes (PBHs) may contribute to the dark matter in our Galaxy. There are strong constraints based on the Hawking evaporation that practically exclude PBHs with masses m~1e15-1e16g and smaller as significant contributors to the Galactic dark matter. Similarly, PBHs with masses greater than about 1e26g are practically excluded by the gravitational lensing observation. The mass range between 10e16g<m<10e26g is unconstrained. In this paper, we examine possible observational signatures in the unexplored mass range, investigating hypothetical collisions of PBHs with main sequence stars, red giants, white dwarfs, and neutron stars in our Galaxy. This has previously been discussed as possibly leading to an observable photon eruption due to shock production during the encounter. We find that such collisions are either too rare to be observed (if the PBH masses are typically larger than about 1e20g), or produce too little power to be detected (if the masses are smaller than about 1e20g).Comment: Accepted for publication in The Astrophysical Journa

The Bending Magnets for the Proton Transfer Line of CNGS

The project "CERN neutrinos to Gran Sasso (CNGS)", a collaboration between CERN and the INFN (Gran Sasso Laboratory) in Italy, will study neutrino oscillations in a long base-line experiment. High-energy protons will be extracted from the CERN SPS accelerator, transported through a 727 m long transfer line and focused onto a graphite target to produce a beam of pions and kaons and subsequently neutrinos. The transfer line requires a total of 78 dipole magnets. They were produced in the framework of an in-kind contribution of Germany via DESY to the CNGS project. The normal conducting dipoles, built from laminated steel cores and copper coils, have a core length of 6.3 m, a 37 mm gap height and a nominal field range of 1.38 T - 1.91 T at a maximum current of 4950 A. The magnet design was a collaboration between CERN and BINP. The half-core production was subcontracted to EFREMOV Institute; the coil fabrication, magnet assembly and the field measurements were concluded at BINP in June 2004. The main design issues and results of the acceptance tests, including mechanical, electrical and magnetic field measurements, are discussed

Polariton propagation in weak confinement quantum wells

Exciton-polariton propagation in a quantum well, under centre-of-mass quantization, is computed by a variational self-consistent microscopic theory. The Wannier exciton envelope functions basis set is given by the simple analytical model of ref. [1], based on pure states of the centre-of-mass wave vector, free from fitting parameters and "ad hoc" (the so called additional boundary conditions-ABCs) assumptions. In the present paper, the former analytical model is implemented in order to reproduce the centre-of-mass quantization in a large range of quantum well thicknesses (5a_B < L < inf.). The role of the dynamical transition layer at the well/barrier interfaces is discussed at variance of the classical Pekar's dead-layer and ABCs. The Wannier exciton eigenstates are computed, and compared with various theoretical models with different degrees of accuracy. Exciton-polariton transmission spectra in large quantum wells (L>> a_B) are computed and compared with experimental results of Schneider et al.\cite{Schneider} in high quality GaAs samples. The sound agreement between theory and experiment allows to unambiguously assign the exciton-polariton dips of the transmission spectrum to the pure states of the Wannier exciton center-of-mass quantization.Comment: 15 pages, 15 figures; will appear in Phys.Rev.

Peak Stir Zone Temperatures during Friction Stir Processing

The stir zone (SZ) temperature cycle was measured during the friction stir processing (FSP) of NiAl bronze plates. The FSP was conducted using a tool design with a smooth concave shoulder and a 12.7-mm step-spiral pin. Temperature sensing was accomplished using sheathed thermocouples embedded in the tool path within the plates, while simultaneous optical pyrometry measurements of surface temperatures were also obtained. Peak SZ temperatures were 990 ⁰Cto 1015 ⁰C (0.90 to 0.97 TMelt) and were not affected by preheating to 400⁰C, although the dwell time above 900 ⁰C was increased by the preheating. Thermocouple data suggested little variation in peak temperature across the SZ, although thermocouples initially located on the advancing sides and at the centerlines of the tool traverses were displaced to the retreating sides, precluding direct assessment of the temperature variation across the SZ. Microstructure-based estimates of local peak SZ temperatures have been made on these and on other similarly processed materials. Altogether, the peak-temperature determinations from these different measurement techniques are in close agreement

Предикторы отмены генно-инженерных биологических препаратов ввиду развития нежелательных явлений у пациентов с ревматоидным артритом

Currently, a large number of highly effective biologic disease modifying antirheumatic drugs (bDMARDs) and targeted synthetic DMARDs (tsDMARDs) are used for the treatment of rheumatoid arthritis (RA). However, in addition to effectiveness, it is necessary to evaluate the risk of adverse events (AEs) when using them.Objective: to determine the predictors of bDMARDs and tsDMARDs discontinuation due to AEs in patients with RA.Patients and methods. The study included 661 patients with RA who took bDMARDs and tsDMARDs. The search for predictors of targeted therapy discontinuation due to AEs was carried out in two stages. At the first stage, using the Kaplan-Meier method, we selected indicators that showed the greatest significant single-factor relationship with the duration of retention on therapy. At the second stage, significant independent indicators were obtained by iterative selection of variables within the multivariate proportional risk model according to Cox.Results and discussion. The presence of rheumatoid nodules (p&lt;0.001), high doses of glucocorticoids (GC; p&lt;0.001), low doses of methotrexate (MT; p=0.009) are significant independent factors for increasing the risk of drugs discontinuation due to the development of AEs. The type of bDMARDs/tsDMARD used also significantly correlated with the risk of discontinuation of therapy due to AEs. A relatively high risk of treatment discontinuation was observed with infliximab (IFN) and certolizumab pegol (CZP). Cancellation of IFN was associated with the occurrence of infusion reactions and infectious complications, and CZP was associated with infectious complications.Conclusion. An increase in the dose of MT and decrease in the use of GCs can help prevent the development of AEs leading to the abolition of biologics and tsDMARDs. Significant differences were found between bDMARDs in terms of the risk of their cancellation due to AEs.В настоящее время для лечения ревматоидного артрита (РА) используется большое число генно-инженерных биологических (ГИБП) и таргетных синтетических базисных противовоспалительных препаратов (тсБПВП), которые обладают высокой эффективностью. Однако, помимо эффективности, необходимо оценивать риск возникновения нежелательных явлений (НЯ) при их использовании.Цель исследования — определить предикторы отмены ГИБП и тсБПВП из-за НЯ у пациентов с РА.Пациенты и методы. В исследование включен 661 пациент с РА, принимавший ГИБП и тсБПВП. Поиск предикторов отмены таргетной терапии ввиду НЯ проводился в два этапа. На первом этапе с помощью метода Каплана—Майера были отобраны показатели, которые демонстрировали наибольшую значимую однофакторную связь с длительностью удержания на терапии. На втором этапе значимые независимые показатели были получены путем пошагового отбора переменных в рамках многофакторной модели пропорционального риска по Коксу.Результаты и обсуждение. Наличие ревматоидных узелков (p&lt;0,001), высокие дозы глюкокортикоидов (ГК; p&lt;0,001), низкие дозы метотрексата (МТ; p=0,009) являются значимыми независимыми факторами увеличения риска отмены препаратов из-за развития НЯ. Используемый ГИБП/тсБПВП также значимо коррелировал с риском отмены терапии из-за НЯ. Относительно высокий риск прекращения лечения был отмечен у инфликсимаба (ИНФ) и цертолизумаба пэгола (ЦЗП). Отмена ИНФ была связана с возникновением инфузионных реакций и инфекционных осложнений, а ЦЗП — с инфекционными осложнениями.Заключение. Увеличение дозы МТ, уменьшение использования ГКмогут способствовать предотвращению развития НЯ, приводящих к отмене ГИБП и тсБПВП. Выявлены существенные различия между ГИБП в отношении риска их отмены вследствие НЯ