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Manufacturing of miniaturized high activity iridium-192 ( Ir) sources have been made a market preference in modern brachytherapy. Smaller dimensions of the sources are flexible for smaller diameter of the applicators, and it is also suitable for interstitial implants. Presently, cobalt-60 ( Co) sources have been commercialized as an alternative to Ir sources for high-dose-rate (HDR) brachytherapy, since Co source have an advantage of longer half-life comparing with Ir source. One of them is the HDR Co Flexisource manufactured by Elekta. The purpose of this study was to compare the TG-43 dosimetric parameters of HDR flexi Co and HDR microSelectron Ir sources. Monte Carlo simulation code of Geant4 (v.11.0) was applied. Following the recommendations of AAPM TG-43 formalism report, Monte Carlo code of HDR flexi Co and HDR microSelectron Ir was validated by calculating radial dose function, anisotropy function, and dose-rate constants in a water phantom. Finally, results of both radionuclide sources were compared. The calculated dose-rate constants per unit air-kerma strength in water medium were 1.108 cGy h U for HDR microSelectron Ir, and 1.097 cGy h U for HDR flexi Co source, with the percentage uncertainty of 1.1% and 0.2%, respectively. The values of radial dose function for distances above 22 cm for HDR flexi Co source were higher than that of the other source. The anisotropic values sharply increased to the longitudinal sides of HDR flexi Co source, and the rise was comparatively sharper to that of the other source. The primary photons from the lower-energy HDR microSelectron Ir source have a limited range and are partially attenuated when considering the results of radial and anisotropic dose distribution functions. This implies that a HDR flexi Co radionuclide could be used to treat tumors beyond the source compared with a HDR microSelectron Ir source, despite the fact that Ir has a lower exit dose than HDR flexi Co radionuclide source.

This paper compares the isotopes (60)Co and (192)Ir as radiation sources for high-dose-rate (HDR) afterloading brachytherapy. The smaller size of (192)Ir sources made it the preferred radionuclide for temporary brachytherapy treatments. Recently also (60)Co sources have been made available with identical geometrical dimensions. This paper compares the characteristics of both nuclides in different fields of brachytherapy based on scientific literature. In an additional part of this paper reports from medical physicists of several radiation therapy institutes are discussed. The purpose of this work is to investigate the advantages or disadvantages of both radionuclides for HDR brachytherapy due to their physical differences. The motivation is to provide useful information to support decision-making procedures in the selection of equipment for brachytherapy treatment rooms. The results of this work show that no advantages or disadvantages exist for (60)Co sources compared to (192)Ir sources with regard to clinical aspects. Nevertheless, there are potential logistical advantages of (60)Co sources due to its longer half-life (5.3 years vs. 74 days), making it an interesting alternative especially in developing countries.

A robust genome editing pipeline is critical to the vitality of a modern genetic laboratory. Previous studies have shown that Cas9 ribonucleoprotein (RNP)-based editing can be highly effective in Caenorhabditis elegans, particularly... CRISPR-based genome editing using ribonucleoprotein complexes and synthetic single-stranded oligodeoxynucleotide (ssODN) donors can be highly effective. However, reproducibility can vary, and precise, targeted integration of longer constructs—such as green fluorescent protein tags remains challenging in many systems. Here, we describe a streamlined and optimized editing protocol for the nematode Caenorhabditis elegans. We demonstrate its efficacy, flexibility, and cost-effectiveness by affinity-tagging 14 Argonaute proteins in C. elegans using ssODN donors. In addition, we describe a novel PCR-based, partially single-stranded, “hybrid” donor design that yields high efficiency editing with large (kilobase-scale) constructs. We use these hybrid donors to introduce fluorescent protein tags into multiple loci, achieving editing efficiencies that approach those previously obtained only with much shorter ssODN donors. The principals and strategies described here are likely to translate to other systems, and should allow researchers to reproducibly and efficiently obtain both long and short precision genome edits.

This paper presents a novel FPGA architecture of high dynamic range (HDR) video processing pipeline, based on the capturing of a sequence of differently exposed images. An acquisition process enabling multi-exposure HDR as well as fast implementation of local tone mapping operator involving bilateral filtering is proposed. The HDR acquisition process is enhanced by the application of novel deghosting method, which is dedicated for hardware implementation and proposed in this paper. The hardware processing pipeline is designed with regards to efficiency and performance and the calculations are performed in fixed point arithmetic. The pipeline is suitable for programmable hardware (FPGA—Field Programmable Gate Arrays) implementation and it achieves real-time performance on full HD HDR video which overcomes state-of-the-art solutions that use local tone mapping and deghosting algorithm.

This paper proposes a novel ghost-free High Dynamic Range (HDR) multi-exposure video acquisition suitable for real-time implementation in embedded systems. While the method is limited to stationary cameras, it achieves, with low requirements on resources, results comparable to state-of-the-art de-ghosting methods that are often very computationally expensive and almost impossible to implement in smart cameras and embedded systems. The paper describes the method itself and includes an evaluation of the performance on selected embedded platforms and a comparison of the results to the state of the art using HDR datasets.

A lateral overflow integration capacitor (LOFIC) complementary metal oxide semiconductor (CMOS) image sensor can realize high-dynamic-range (HDR) imaging with combination of a low-conversion-gain (LCG) signal for large maximum signal electrons and a high-conversion-gain (HCG) signal for electron-referred noise floor. However, LOFIC-CMOS image sensor requires a two-channel read-out chain for LCG and HCG signals whose polarities are inverted. In order to provide an area-efficient LOFIC-CMOS image sensor, a one-channel read-out chain that can process both HCG and LCG signals is presented in this paper. An up/down double-sampling circuit composed of an inverting amplifier for HCG signals and a non-inverting attenuator for LCG signals can reduce the area of the read-out chain by half compared to the conventional two-channel read-out chain. A test chip is fabricated in a 0.18 μm CMOS process with a metal–insulator–metal (MIM) capacitor, achieving a readout noise of 130 μVrms for the HCG signal and 1.19 V for the LCG input window. The performance is equivalent to 103 dB of the dynamic range with our previous LOFIC pixel in which HCG and LCG conversion gains are, respectively, 160 μV/e− and 10 μV/e−.

Abstract Melting and fast cooling double stranded DNA donor molecules prior to injection dramatically increases the frequency of homology-directed repair for edits such as insertions of fluorescent protein markers in Caenorhabditis elegans. Strategies described here enable consistently ... Abstract CRISPR genome editing has revolutionized genetics in many organisms. In the nematode Caenorhabditis elegans, one injection into each of the two gonad arms of an adult hermaphrodite exposes hundreds of meiotic germ cells to editing mixtures, permitting the recovery of multiple indels or small precision edits from each successfully injected animal. Unfortunately, particularly for long insertions, editing efficiencies can vary widely, necessitating multiple injections, and often requiring coselection strategies. Here, we show that melting double-stranded DNA (dsDNA) donor molecules prior to injection increases the frequency of precise homology-directed repair (HDR) by several fold for longer edits. We describe troubleshooting strategies that enable consistently high editing efficiencies resulting, for example, in up to 100 independent GFP knock-ins from a single injected animal. These efficiencies make C. elegans by far the easiest metazoan to genome edit, removing barriers to the use and adoption of this facile system as a model for understanding animal biology.

Light adaptation or brightness correction is a key step in improving the contrast and visual appeal of an image. There are multiple light-related tasks (for example, low-light enhancement and exposure correction) and previous studies have mainly investigated these tasks individually. It is interesting to consider whether the common light adaptation sub-problem in these light-related tasks can be executed by a unified model, especially considering that our visual system adapts to external light in such way. In this study, we propose a biologically inspired method to handle light-related image enhancement tasks with a unified network (called LA-Net). First, we proposed a new goal-oriented task decomposition perspective to solve general image enhancement problems, and specifically decouple light adaptation from multiple light-related tasks with frequency-based decomposition. Then, a unified module is built inspired by biological visual adaptation to achieve light adaptation in the low-frequency pathway. Combined with the proper noise suppression and detail enhancement along the high-frequency pathway, the proposed network performs unified light adaptation across various scenes. Extensive experiments on three tasks—low-light enhancement, exposure correction, and tone mapping—demonstrate that the proposed method obtains reasonable performance simultaneously for all of these three tasks compared with recent methods designed for these individual tasks. Our code is made publicly available at https://github.com/kaifuyang/LA-Net.

Hydraulic fracturing (HF) is a well-known stimulation method used to increase production from conventional and unconventional hydrocarbon reservoirs. In recent years, HF has been widely used in Enhanced Geothermal Systems (EGS). HF in EGS is used to create a geothermal collector in impermeable or poor-permeable hot rocks (HDR) at a depth formation. Artificially created fracture network in the collector allows for force the flow of technological fluid in a loop between at least two wells (injector and producer). Fluid heats up in the collector, then is pumped to the surface. Thermal energy is used to drive turbines generating electricity. This paper is a compilation of selected data from 10 major world’s EGS projects and provides an overview of the basic elements needed to design HF. Authors were focused on two types of data: geological, i.e., stratigraphy, lithology, target zone deposition depth and temperature; geophysical, i.e., the tectonic regime at the site, magnitudes of the principal stresses, elastic parameters of rocks and the seismic velocities. For each of the EGS areas, the scope of work related to HF processes was briefly presented. The most important HF parameters are cited, i.e., fracturing pressure, pumping rate and used fracking fluids and proppants. In a few cases, the dimensions of the modeled or created hydraulic fractures are also provided. Additionally, the current state of the conceptual work of EGS projects in Poland is also briefly presented.

This paper examines methods to best exploit the High Dynamic Range (HDR) of the single photon avalanche diode (SPAD) in a high fill-factor HDR photon counting pixel that is scalable to megapixel arrays. The proposed method combines multi-exposure HDR with temporal oversampling in-pixel. We present a silicon demonstration IC with 96 × 40 array of 8.25 µm pitch 66% fill-factor SPAD-based pixels achieving >100 dB dynamic range with 3 back-to-back exposures (short, mid, long). Each pixel sums 15 bit-planes or binary field images internally to constitute one frame providing 3.75× data compression, hence the 1k frames per second (FPS) output off-chip represents 45,000 individual field images per second on chip. Two future projections of this work are described: scaling SPAD-based image sensors to HDR 1 MPixel formats and shrinking the pixel pitch to 1–3 µm.