Horizon effects with surface waves on moving water

Surface waves on a stationary flow of water are considered, in a linear model that includes the surface tension of the fluid. The resulting gravity-capillary waves experience a rich array of horizon effects when propagating against the flow. In some cases three horizons (points where the group velocity of the wave reverses) exist for waves with a single laboratory frequency. Some of these effects are familiar in fluid mechanics under the name of wave blocking, but other aspects, in particular waves with negative co-moving frequency and the Hawking effect, were overlooked until surface waves were investigated as examples of analogue gravity [Sch\"utzhold R and Unruh W G 2002 Phys. Rev. D 66 044019]. A comprehensive presentation of the various horizon effects for gravity-capillary waves is given, with emphasis on the deep water/short wavelength case kh>>1 where many analytical results can be derived. A similarity of the state space of the waves to that of a thermodynamic system is pointed out.Comment: 30 pages, 15 figures. Minor change

The Basics of Water Waves Theory for Analogue Gravity

This chapter gives an introduction to the connection between the physics of water waves and analogue gravity. Only a basic knowledge of fluid mechanics is assumed as a prerequisite.Comment: 36 pages. Lecture Notes for the IX SIGRAV School on "Analogue Gravity", Como (Italy), May 201

Novel allosteric mechanism of p53 activation by small molecules for targeted anticancer therapy

Given the immense significance of p53 restoration for anti-cancer therapy and that p53-activating molecules are in clinical trials, elucidation of the mechanisms of action of p53-activating molecules is of the utmost importance. Here we report a discovery of a novel allosteric modulation of p53 by small molecules, which is an unexpected turn in the p53 story. We identified a structural element involved in allosteric regulation of p53, whose targeting by small molecules RITA, PpIX and licofelone blocks the binding of two p53 inhibitors, MDM2 and MDMX, thereby restoring p53 function. Deletion and mutation analysis followed by molecular modeling and its thorough validation, identified the key p53 residues S33 and S37 targeted by RITA and PpIX. We propose that the binding of small molecules to the identified site in p53 induces a conformational trap preventing p53 from the interaction with MDM2 and MDMX. These results point to a high potential of allosteric activators as targeted drugs. Our study provides a basis for the development of therapeutics with a novel mechanism of action, thus extending the p53 pharmacopeia

Chemistry for Sustainable Development 21 (2013) 4751 One-Stage Synthesis of Propylene from Ethylene Using PdRe 2 O 7 /B 2 O 3 Al 2 O 3 Catalyst

Abstract Equilibrium was investigated concerning the sorption of palladium from the H 2 PdCl 4 and Pd(NH 3 ) 4 Cl 2 solutions onto B 2 O 3 Al 2 O 3 carrier. It is demonstrated that the sorption equilibrium is described by Langmuir equation. According the results of testing the Pd/B 2 O 3 Al 2 O 3 samples in the course of oligomerization it has been found that the optimum content of palladium in the catalyst should be equal to 0.5 mass %, whereas the optimum precursor of palladium should be presented by palladium chloride complex. The catalytic properties of PdRe 2 O 7 /B 2 O 3 Al 2 O 3 system in the one-stage propylene synthesis from ethylene were studied. It has been demonstrated that it is possible to obtain propylene with the yield equal to 77 83 % with respect to the theoretically determined one

Real-Time video server implementation for a mobile robot

© 2018 IEEE. Most of robots are using vision for various applications. In some cases, mobile robots are provided with an insufficient onboard processing hardware, and therefore video from cameras needs to be transmitted in an efficient and reliable way to a more powerful system for further off-board processing. Multiple difficulties could be faced during video streaming software development, including high latencies, network congestion, packet losses, distortions and others, which makes trade-offs between video quality, bitrate, frame rate, and packet loss inevitable. Thus, the key problem is to find such parameters, which will satisfy the specified needs. In our work we implement a video streaming server on mobile robot Servosila Engineer. A set of experiments demonstrated that high bitrates and frame rates increase load on CPU. Packet losses could be mitigated by decreasing bitrate to 100-200 kbps

Real-Time video server implementation for a mobile robot

© 2018 IEEE. Most of robots are using vision for various applications. In some cases, mobile robots are provided with an insufficient onboard processing hardware, and therefore video from cameras needs to be transmitted in an efficient and reliable way to a more powerful system for further off-board processing. Multiple difficulties could be faced during video streaming software development, including high latencies, network congestion, packet losses, distortions and others, which makes trade-offs between video quality, bitrate, frame rate, and packet loss inevitable. Thus, the key problem is to find such parameters, which will satisfy the specified needs. In our work we implement a video streaming server on mobile robot Servosila Engineer. A set of experiments demonstrated that high bitrates and frame rates increase load on CPU. Packet losses could be mitigated by decreasing bitrate to 100-200 kbps

Three-dimensional magnetic recording: An emerging nanoelectronic technology

An overview of three-dimensional magnetic recording as a next-generation nanoelectronic data storage technology is presented. It is proposed to stack magnetic bits in a third (vertical) dimension. Several implementations of a three-dimensional recording system are analyzed. A clear distinction between absolute three-dimensional recording and its trivial multilevel implementation is drawn. The main focus is on the study of write and read processes. One of the proposed mechanisms to access data during writing and reading is to control a relatively strong and adequately localized magnetic field using a patterned soft magnetic underlayer under the three-dimensional recording media. During the write process, the use of the underlayer allows increasing the recording field and simultaneously maintaining adequate high resolution across the entire thickness of the recording media. Similarly, according to the reciprocity principle, during the readback process, the "softness" of the underlayer strongly influences the sensitivity field and thus could be used as a mechanism to identify a unifield plane across the thickness. As an option, it is proposed to minimize the intersymbol interference and improve stability through patterning of the recording media in all three dimensions. The physics of three-dimensional magnetic recording is investigated via the nanoprecision spinstand measurements, magnetic force microscopy, and Landau-Lifshits-Gilbert-based micromagnetic modeling

PERIPHERAL VENO-ARTERIAL ECMO AS MECHANICAL CIRCULATORY SUPPORT BEFORE HEART TRANSPLANTATION

Aim of our clinical study was evaluation own initial experience of high-urgency ortotopic heart transplantation (OHT) in recipients, who were bridged on peripheral Vena-Arterial Extracorporeal Membrane Oxygenation (VA ECMO). Materials and methods. In this study was included 17 patients (14/3 M/F, age 16–66 (40.1 ± 4.2 yrs)) who underwent OHT while on peripheral ECMO support. In all cases we used peripheral surgical can- nulation technique via femoral vessels – arterial cannula 15–19 Fr, venous cannula – 21–25 Fr, arterial cannula or vascular catheter 8–10 Fr for anterograde leg’s perfusion. Results. Duration Vena-Arterial Extracorporeal Membrane Oxygenation before OHT was 81 ± 17 h. VA ECMO support was blood flow 4.8 ± 0.6 l/min or 2.63 ± 0/04 l/min/m2, gas flow 4.8 ± 0.6 l/min, FiO2 0.86 ± 0.07. Vena-Arterial Extracorporeal Membrane Oxygenation support was continued in “protective mode” (blood flow 1.9 ± 0.2 l/min) 4.3 ± 0.5 days after OHT. Thirteen pa- tients (76.4%) were weaned from VA ECMO successfully and survived to be discharged. ICU and hospital LOS after orthotopic heart transplantation was respectively 6.7 ± 0.8 and 32.3 ± 4.6 days in group of survived patients. The reasons of a lethal outcome (n = 4, 23.5%) were sepsis and multiorgan failure (n = 3), sudden cardiac arrest (n = 1). Conclusion. Vena-Arterial Extracorporeal Membrane Oxygenation is a favorable short-term method of circulatory support in patients who needed in high-urgency heart transplantation