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BackgroundUltra-high dose rate (UHDR) radiation of electron or proton beam has been shown to spare normal tissues surrounding the tumors while killing tumor cells effectively which is called the FLASH effect (FE). However, the internal mechanisms of FE has not yet been fully revealed, and the optimal parameter range for its use remains unknown.PurposeThis study aims to design an UHDR cell irradiation experimental platform that provides a stable, appropriate and wide range of adjustable dose and average dose rates for exploring the FE dependence on total dose.MethodsBased on a 7 MeV medical proton linear injector, a single scattering nozzle was designed and optimized using the Monte Carlo code FLUKA. A 40-μm-thick tantalum foil, acting as both a vacuum window and a scatterer, was comprised in the nozzle with a source-to-surface distance of 26 cm. Finally, a single pulsed shoot-through UHDR cell penetration irradiation experiment was conducted by simulation using optimized parameters for this platform.ResultsThe simulation results demonstrate that the experimental platform can provide a 2 cm diameter irradiation field with a dose homogeneity of 4.9%. By adjusting the beam intensities (0.1~1 mA) and pulse widths (20~200 μs) of proton beam pulses, the dose and corresponding average dose rate of this platform can be adjusted within the range of 6~667 Gy and 3.3×105~3.3×106 Gy·s-1, respectively. Results of simulated UHDR cell irradiation experiment show that the monolayer cells can be irradiated using a single pulsed shoot-through mode with a dose rate of 3.3×105 Gy·s-1 and doses ranging from 7~40 Gy.ConclusionThis platform enables UHDR experiments to explore the FE dependence on total dose, providing further experimental data for clarifying the FE mechanisms.

Copyright of Journal of Signal Processing is the property of Journal of Signal Processing and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Laser Technology is the property of Gai Kan Bian Wei Hui and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

FLASH radiotherapy is a novel method that has the potential to improve the therapeutic gain ratio to a new level. FLASH radiotherapy technology is mainly characterized by irradiation at ultra-high dose rate, which can reduce radiation-induced injury to normal tissues during radiotherapy, while maintaining the ability of radiation damage to tumors. On the one hand, as a new radiotherapy technology, the radiobiological mechanisms of FLASH are unclear, which hinders its clinical transformation. On the other hand, there are many technical difficulties in the clinical application of ultra-high dose rate irradiation technology. This paper summarizes the research progress of radiobiological mechanisms underlying FLASH radiotherapy, as well as the challenges and possible solutions associated with FLASH radiotherapy treatment plans, to provide a reference for clinical translation of subsequent FLASH radiotherapy.

NAND flash based solid state disks (SSD) have better performance than magnetic disks and are gradually replacing hard disks in desktop systems. However, although DRAM is embedded in SSD as a buffer, SSD may also produce unstable write performance with continuous writing, because non-overwrite write and garbage collection(GC) operations are frequently triggered when physical pages are written. Aiming at this problem, a new flash buffer management strategy called PRLRU (least recently used algorithm by page reconstruction) is proposed, which manages the buffer through the page reconstruction mechanism and the data temperature recognition mechanism. The page reconfiguration mechanism combines pages with valid data that are less than one page size with other pages and then writes back to the flash memory to reduce the actual write operation by minimizing the number of non-overwrite write operations. The data temperature recognition mechanism performs temperature level marking on the cached pages, and then writes back the pages in a predetermined priority order. Test it with real workloads, the experimental results show that PRLRU can effectively improve SSD performance and prolong SSD lifetime. Compared with LRU, BPLRU and 2QW-Clock, the write performance of PRLRU is increased by 34.5%, 22.8% and 28.8%, respectively on average, the read performance increased by 12.5%, 10.6% and 8.3%, respectively on average, and the amount of garbage collection decreased by 10.5%, 8.7% and 6.3%, respectively on average.

Copyright of Journal of Frontiers of Computer Science & Technology is the property of Beijing Journal of Computer Engineering & Applications Journal Co Ltd. and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Experimental Technology & Management is the property of Experimental Technology & Management Editorial Office and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Journal of Test & Measurement Technology is the property of Publishing Center of North University of China and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Studia Poliana is the property of Studia Poliana and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

A set of Bootloader experimental system based on STM32 is designed. This system mainly completes two functions such as the boot loading and user interaction. The storage mode adopts the structure design of "multi-system storage" to design the three different working modes in the boot loading process and set up different instructions in the user interaction part with different privileges. This system provides practical exercises with corresponding difficulty for students at different levels, and guides them to consolidate theoretical knowledge, actively explore and improve their innovative ability. [ABSTRACT FROM AUTHOR]

Copyright of Public Art is the property of Shanghai Fine Arts Publisher Ltd. co. and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Based on pre-fetch and cache principles, we realize a Flash acceleration controller which is used to improve the efficiency of Flash memory in different embedded applications. The controller contains two acceleration schemes: prefetch cache and high-speed cache. The pre-fetch-cache method uses the data width extension and pre-fetch technology to accelerate the access to sequence instructions, and uses the branch-buffer technology to reduce the missing penalty caused by the branch instruction. The high-speed cache method uses the set-associative and way-predict technology to improve instruction reuse and reduce the Flash access frequency and power consumption. The two acceleration methods can not only be selected statically by configuring related registers, but also be switched dynamically by the software flow. Several benchmark results prove the feasibility and efficiency of the proposed Flash acceleration controller in terms of performance and power optimization. [ABSTRACT FROM AUTHOR]

Copyright of Chinese Journal of Liquid Crystal & Displays is the property of Chinese Journal of Liquid Crystal & Displays and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

In order to relax the tension of insufficiency of corpse and improve the experiment teaching quality of anatomy, the virtual experiment of anatomy is realized by Action Script language. It overcomes the shortcomings of traditional experiment and makes it stronger. At the same time, this virtual experiment arouses the students' interest, abates the cost and helps the students to do the experiment when they want to. This changes the traditional teaching methods and has a good teaching effect. [ABSTRACT FROM AUTHOR]

Based on the investigation of experimentation and aerodynamics theory, live interactive web aerodynamics virtual experiment platform is built up. Using MVC (Model-View-Controller) design pattern, the system has better scalability and ease of maintenance. The platform chooses ActionScript3 as a development tool, focusing on the accumulation of reusable control modules with class binding technology. It's important for the system function expansion and development of other project. The system has all around functions, strong sense of immersion, hence satisfying the demands of experiment operation trainning and the experiment courses online study. [ABSTRACT FROM AUTHOR]

On basis of the constitutive equation of FGH96 alloy and the relation between friction coefficient and temperature, the coupled thermo-mechanical model of inertia friction welding of FGH96 alloy is established using DEFORM software. The relation between the flash forming and material flow is investigated. The results show that the flash doesn't appear in the early stage of welding because the temperature and the velocity of material flow are both small. After the welding process reaches stable state, the material near two edges of friction edge flows towards the outside of friction surface, which results in the appearance of flash and the dimensions of flash increase with the continuance of welding time. With the increase of the initial velocity or the axial press, both the dimension and the bending extent of the flash are increased. Moreover, the method to determine the reasonable welding parameters is put forward based on the appearance of the flash. [ABSTRACT FROM AUTHOR]