Readout Capability Research Articles

Characterization of a diode dosimeter for UHDR FLASH radiotherapy.

Ultra-high dose rate (UHDR) FLASH beams typically deliver dose at rates of >40 Gy/sec. Characterization of these beams with respect to dose, mean dose rate, and dose per pulse requires dosimeters which exhibit high temporal resolution and fast readout capabilities. A diode EDGE Detector with a newly designed electrometer has been characterized for use in an UHDR electron beam and demonstrated appropriateness for UHDR FLASH radiotherapy dosimetry. Dose linearity, mean dose rate, and dose per pulse dependencies of the EDGE Detector were quantified and compared with dosimeters including a W1 scintillator detector, radiochromic film, and ionization chamber that were irradiated with a 10 MeV UHDR beam. The dose, dose rate, and dose per pulse were controlled via an in-house developed scintillation-based feedback mechanism, repetition rate of the linear accelerator, and source-to-surface distance, respectively. Depth-dose profiles and temporal profiles at individual pulse resolution were compared to the film and scintillation measurements, respectively. The radiation-induced change in response sensitivity was quantified via irradiation of ∼5kGy. The EDGE Detector agreed with film measurements in the measured range with varying dose (up to 70 Gy), dose rate (nearly 200 Gy/s), and dose per pulse (up to 0.63 Gy/pulse) on average to within 2%, 5%, and 1%, respectively. The detector also agreed with W1 scintillation detector on average to within 2% for dose per pulse (up to 0.78 Gy/pulse). The EDGE Detector signal was proportional to ion chamber (IC) measured dose, and mean dose rate in the bremsstrahlung tail to within 0.4% and 0.2% respectively. The EDGE Detector measured percent depth dose (PDD) agreed with film to within 3% and per pulse output agreed with W1 scintillator to within -6% to +5%. The radiation-induced response decrease was 0.4% per kGy. The EDGE Detector demonstrated dose linearity, mean dose rate independence, and dose per pulse independence for UHDR electron beams. It can quantify the beam spatially, and temporally at sub millisecond resolution. It's robustness and individual pulse detectability of treatment deliveries can potentially lead to its implementation for in vivo FLASH dosimetry, and dose monitoring.

Bare glassy nanopore for length-resolution reading of PCR amplicons from various pathogenic bacteria and viruses

In this study, it is confirmed that without addition of organic solvent and embedding polymer hydrogel into glass nanopore, bare glass nanopore can faithfully measure various lengths of DNA duplexes from 200 to 3000 base pairs with 200 base pairs resolution, showing well-separated peak amplitudes of blockage currents. Furthermore, motivated by this readout capability of duplex DNA, amplicons from Polymerase Chain Reaction (PCR) amplification are straightforwardly discriminated by bare glassy nanopore without fluorescent labeling. Except simultaneous discrimination of up to 7 different segments of the same lambda genome, various pathogenic bacteria and viruses including SARS-CoV-2 and its mutants in clinical samples can be discriminated at high resolution. Moreover, quantitative measurement of PCR amplicons is obtained with detection range spanning from 0.75 aM to 7.5 pM and detection limit of 7.5 aM, which reveals that bare glass nanopore can faithfully disclose PCR results without any extra labeling.

Non-volatile optical memory based on cooperative orientation switching: improvement of recording speed and contrast by utilizing out-of-plane orientation mode.

Herein, we report a novel strategy toward non-volatile optical memory with high-contrast, high-speed recording, and non-destructive readout capability based on the cooperative out-of-plane orientation of a fluorescent dye doped into azobenzene liquid crystalline polymer film. By employing the out-of-plane orientation switching upon irradiation with UV light and thermal heating, high-contrast turn-on fluorescence switching was successfully achieved and the optical recording was demonstrated with non-destructive fluorescence readout capability. Furthermore, the recording speed and the fluorescence on/off contrast in the present system were dramatically improved compared to the previous in-plane orientation mode.

Competitive reversed quartet mechanisms for photogenerated ground state electron spin polarization.

Photoinduced electron spin polarization (ESP) of a spin-½ organic radical (nitronyl nitroxide, NN) in a series of Pt(ii) complexes comprised of 4,4'-di-tert-butyl-2,2'-bipyridine (bpy) and 3-tert-butylcatecholate (CAT) ligands, where the CAT ligand is substituted with (CH3)n-meta-phenyl-NN (bridge-NN) groups, is presented and discussed. We show the importance of attenuating the energy gap between localized NN radical and chromophoric excited states to control both the magnitude and sign of the optically-generated ESP, and to provide deeper insight into the details of the ESP mechanism. Understanding electronic structure contributions to optically generated ESP will enhance our ability to control the nature of prepared states for a variety of quantum information science applications, where strong ESP facilitates enhanced sensitivity and readout capabilities at low applied magnetic fields and higher temperatures.

Emerging integrated SERS-microfluidic devices for analysis of cancer-derived small extracellular vesicles.

Cancer-derived small extracellular vesicles (sEVs) are specific subgroups of lipid bilayer vesicles secreted from cancer cells to the extracellular environment. They carry distinct biomolecules (e.g., proteins, lipids and nucleic acids) from their parent cancer cells. Therefore, the analysis of cancer-derived sEVs can provide valuable information for cancer diagnosis. However, the use of cancer-derived sEVs in clinics is still limited due to their small size, low amounts in circulating fluids, and heterogeneous molecular features, making their isolation and analysis challenging. Recently, microfluidic technology has gained great attention for its ability to isolate sEVs in minimal volume. In addition, microfluidics allows the isolation and detection of sEVs to be integrated into a single device, offering new opportunities for clinical application. Among various detection techniques, surface-enhanced Raman scattering (SERS) has emerged as a promising candidate for integrating with microfluidic devices due to its ultra-sensitivity, stability, rapid readout, and multiplexing capability. In this tutorial review, we start with the design of microfluidics devices for isolation of sEVs and introduce the key factors to be considered for the design, and then discuss the integration of SERS and microfluidic devices by providing descriptive examples of the currently developed platforms. Lastly, we discuss the current limitations and provide our insights for utilising integrated SERS-microfluidics to isolate and analyse cancer-derived sEVs in clinical settings.

Wearable Hydrogel-Based Epidermal Sensor with Thermal Compatibility and Long Term Stability for Smart Colorimetric Multi-Signals Monitoring.

Hydrogel-based wearable epidermal sensors (HWESs) have attracted widespread attention in health monitoring, especially considering their colorimetric readout capability. However, it remains challenging for HWESs to work at extreme temperatures with long term stability due to the existence of water. Herein, a wearable transparent epidermal sensor with thermal compatibility and long term stability for smart colorimetric multi-signals monitoring is developed, based on an anti-freezing and anti-drying hydrogel with high transparency (over 90% transmittance), high stretchability (up to 1500%) and desirable adhesiveness to various kinds of substrates. The hydrogel consists of polyacrylic acid, polyacrylamide, and tannic acid-coated cellulose nanocrystals in glycerin/water binary solvents. When glycerin readily forms strong hydrogen bonds with water, the hydrogel exhibits outstanding thermal compatibility. Furthermore, the hydrogel maintains excellent adhesion, stretchability, and transparency after long term storage (45 days) or at subzero temperatures (-20 °C). For smart colorimetric multi-signals monitoring, the freestanding smart colorimetric HWESs are utilized for simultaneously monitoring the pH, T and light, where colorimetric signals can be read and stored by artificial intelligence strategies in a real time manner. In summary, the developed wearable transparent epidermal sensor holds great potential for monitoring multi-signals with visible readouts in long term health monitoring.

4D-tracking in the 10-ps range: A technological perspective

The present paper focuses on recent and ready-to-come advancements concerning high-resolution 4D-tracking with a perspective approach. Four-dimensional-tracking techniques (particle tracking with timing information for each detection point) have revealed a necessity for the next and next-to-next generations of high-energy physics experiments to cope with the increasing luminosity and consequent event pile-up in the beam collision region. Such a decisive challenge concerns both detection and processing technologies at an unprecedented level of difficulty. In addition to the high performance required in space–time measurement precision (some tens of picoseconds resolution in timing and about 10 µm resolution in space), an extremely high radiation hardness is demanded for such technologies together with an extremely high read-out and processing capability. Emerging experimental solutions for sensors and electronics against such challenges are presented here.

Operation of a TPC using the SAMPA chip integrated in the SRS

The SAMPA chip is an ASIC originally designed for the ALICE experiment at CERN and has been adopted by other large experiments. The offer of such systems for smaller, though scalable, experiments and the versatility of this ASIC has pushed towards its implementation as a front-end readout chip for the Scalable Readout System (SRS). In this work we present the first results of the integration of SAMPA in the SRS. To test the electronics and the readout capability a small Time Projection Chamber (10×10×8cm3) was built and cosmic rays were used to generate tracks and to develop the data construction.

AlphaCAMM, a Micromegas-based camera for high-sensitivity screening of alpha surface contamination

Surface contamination of 222Rn progeny from the 238U natural decay chain is one of the most difficult background contributions to measure in rare event searches experiments. In this work we propose AlphaCAMM, a gaseous chamber read with a segmented Micromegas, for the direct measurement of 210Pb surface contamination of flat samples. The detection concept exploits the readout capabilities of the Micromegas detectors for the reconstruction of 210Po alpha tracks to increase the signal-to-background ratio. We report here on the design and realization of a first 26 × 26 cm2 non-radiopure prototype, with which the detection concept is demonstrated by the use of a new algorithm for the reconstruction of alpha tracks. AlphaCAMM aims for minimum detectable 210Pb activities of 100 nBq cm-2 and sensitivity upper limits about 60 nBq cm-2 at 95% of C.L., which requires an intrinsic background level of 5×10-8 alphas cm-2 s-1. We discuss here the prospects to reach these sensitivity goals with a radiopure AlphaCAMM prototype currently under construction.

Organic photoconductive film–stacked active pixel sensor pixel circuits using indium–tin–zinc-oxide thin-film transistors

In this study, we describe the signal readout capabilities of indium–tin–zinc-oxide (ITZO) thin-film transistor (TFT)-based active pixel sensor (APS) pixel circuits combined with organic photoconductive films (OPFs). A pixel circuit was fabricated with a size of 50 μm containing three ITZO TFTs having a channel length of 2 μm and a blue-sensitive OPF possessing excellent properties with an external quantum efficiency of ∼59% and a dark current density of <100 pA cm−2. Signal readout operation of the pixel circuits in accordance with irradiated light intensity was demonstrated, and sufficient response speeds within the line selection period, assuming a pixel number of 320 × 240 (QVGA) at 60 frames per second (∼69.4 μs), was also confirmed by fabricating pixel line arrays comprising 320 and 240 pixels. Our findings show that the miniaturized ITZO TFTs have potential for use in high-pixel-density TFT-based APS image sensors with improved imaging quality.

The upgraded ALICE TPC

A large Time Projection Chamber (TPC) is the main device for tracking and particle identification in the ALICE experiment at the Large Hadron Collider (LHC) at CERN. In the upcoming Run 3, the LHC will deliver lead beams colliding at an interaction rate of up to 50kHz. In order to read out all minimum bias events in Pb–Pb collisions, the TPC was upgraded with an amplification stage based on Gas Electron Multipliers (GEM) and new front-end electronics. With the new amplification stage, a trigger-less operation of the TPC becomes possible, resulting in a continuous readout without dead time.The exchange of the readout chambers and front-end electronics took place in a dedicated clean room in 2019/20. The upgraded TPC was then moved back to its designated position at the interaction point 2 of the LHC and an extensive commissioning programme was carried out. It includes, inter alia, noise studies, measurements of laser tracks, irradiation of the TPC with an intense X-ray source, the flushing of radioactive 83mKr into the active volume and the operation during the first proton–proton collisions provided by the LHC. During these measurements, the TPC operated at nominal conditions and the continuous readout capability was tested successfully.

Mussel-inspired Fe-based Tannic acid Nanozyme: A renewable bioresource-derived high-affinity signal tag for dual-readout multiplex lateral flow immunoassay

Lateral flow immunoassay (LFIA) is a paper-based point-of-care (POC) diagnostic tool for widespread applications. Nonetheless, the lack of multi-target monitor capability, high-affinity between signal tag and antibody, and multi-signal readout capability still remain challenges. Herein, a mussel-inspired Fe-based Tannic acid (TA) Nanozyme (FTAN) mediated dual-readout and dual-semiquantitative multiplex lateral flow immunoassay (MLFIA) was strategically fabricated by employing ractopamine (RAC) and clenbuterol (CLE) as proof-of-concept. Avail of the environment-friendly, cost-effective, darker original color, and dual-signal readout capacity, FTAN was innovatively designed by chelating renewable bioresource TA as coupling element and Fe as active center to manufacture a multi-functional signal tag for the first time. Benefiting from the preferential protein adsorption ability of TA-Fe, the mussel-inspired nanozyme achieves satisfactory coupling efficiency and stability with antibodies. Importantly, the whole detection range was divided into several monitoring sections owing to the defined multiple detection limits (originated from on-demand outputs of colorimetric and catalytic signal) and broadened detection range, which contribute to satisfies dual-semiquantitative rapid on-site detection and various limit standards of same target in different regions. This research may contribute to the rational design of high-affinity nanozyme-based signal tags in LFIAs, the exploration of more renewable bioresource-derived nanozymes, and the extension of their applications in relevant sectors.

Hough Transform Proposal and Simulations for Particle Track Recognition for LHC Phase-II Upgrade

In the near future, LHC experiments will continue future upgrades by overcoming the technological obsolescence of the detectors and the readout capabilities. Therefore, after the conclusion of a data collection period, CERN will have to face a long shutdown to improve overall performance, by updating the experiments, and implementing more advanced technologies and infrastructures. In particular, the largest LHC experiment, i.e., ATLAS, will upgrade parts of the detector, the trigger, and the data acquisition system. In addition, the ATLAS experiment will complete the implementation of new strategies, algorithms for data handling, and transmission to the final storage apparatus. This paper presents an overview of an upgrade planned for the second half of this decade for the ATLAS experiment. In particular, we show a study of a novel pattern recognition algorithm used in the trigger system, which is a device designed to provide the information needed to select physical events from unnecessary background data. The idea is to use a well known mathematical transform, the Hough transform, as the algorithm for the detection of particle trajectories. The effectiveness of the algorithm has already been validated in the past, regardless of particle physics applications, to recognize generic shapes within images. On the contrary, here, we first propose a software emulation tool, and a subsequent hardware implementation of the Hough transform, for particle physics applications. Until now, the Hough transform has never been implemented on electronics in particle physics experiments, and since a hardware implementation would provide benefits in terms of overall Latency, we complete the studies by comparing the simulated data with a physical system implemented on a Xilinx hardware accelerator (FELIX-II card). In more detail, we have implemented a low-abstraction RTL design of the Hough transform on Xilinx UltraScale+ FPGAs as target devices for filtering applications.

Impact of COVID-19 on Radiology Trainee Safety, Education, and Wellness: Challenges Experienced and Proposed Solutions for the Future.

Impact of COVID-19 on Radiology Trainee Safety, Education, and Wellness: Challenges Experienced and Proposed Solutions for the Future.

All-optical Mechanobiology Interrogation of Yes-associated Protein in Human Cancer and Normal Cells using a Multi-functional System

Long-term multi-functional imaging and analysis of live cells require streamlined, functional coordination of various hardware and software platforms. However, manual control of various equipment produced by different manufacturers is labor-intensive and time-consuming, potentially decreasing the accuracy, reproducibility, and quality of acquired data. Therefore, an all-in-one and user-programmable system that enables automatic, multi-functional, and long-term image acquisition and is compatible with most fluorescent microscopy platforms can benefit the scientific community. This paper introduces the complete operating protocols of utilizing a novel integrated software system that consists of (1) a home-built software program, titled "Automatic Multi-functional Integration Program (AMFIP)," which enables automatic multi-channel imaging acquisition, and (2) a suite of quantitative imaging analysis and cell traction computation packages. This integrated system is applied to reveal the previously unknown relationship between the spatial-temporal distribution of mechano-sensitive Yes-associated protein (YAP) and the cell mechanics, including cell spreading and traction, in CRISPR/Cas9-engineered human normal cells (B2B) and lung cancer cells (PC9). Leveraging this system's capability of multi-channel control and readout, the result shows: (1) B2B normal cells and PC9 cancer cells show a distinct relationship between YAP expression, traction, and cell dynamics during cell spreading and migration processes; and (2) PC9 cancer cells apply noticeable peri-nuclear forces on substrates. In summary, this paper presents a detailed stepwise protocol on how to utilize an integrated user-programmable system that enables automatic multi-functional imaging and analysis to elucidate YAP mechano-sensitivity. These tools open the possibility for detailed explorations of multifaceted signaling dynamics in the context of cell physiology and pathology.

All-optical Mechanobiology Interrogation of Yes-associated Protein in Human Cancer and Normal Cells using a Multi-functional System.

Long-term multi-functional imaging and analysis of live cells require streamlined, functional coordination of various hardware and software platforms. However, manual control of various equipment produced by different manufacturers is labor-intensive and time-consuming, potentially decreasing the accuracy, reproducibility, and quality of acquired data. Therefore, an all-in-one and user-programmable system that enables automatic, multi-functional, and long-term image acquisition and is compatible with most fluorescent microscopy platforms can benefit the scientific community. This paper introduces the complete operating protocols of utilizing a novel integrated software system that consists of (1) a home-built software program, titled "Automatic Multi-functional Integration Program (AMFIP)," which enables automatic multi-channel imaging acquisition, and (2) a suite of quantitative imaging analysis and cell traction computation packages. This integrated system is applied to reveal the previously unknown relationship between the spatial-temporal distribution of mechano-sensitive Yes-associated protein (YAP) and the cell mechanics, including cell spreading and traction, in CRISPR/Cas9-engineered human normal cells (B2B) and lung cancer cells (PC9). Leveraging this system's capability of multi-channel control and readout, the result shows: (1) B2B normal cells and PC9 cancer cells show a distinct relationship between YAP expression, traction, and cell dynamics during cell spreading and migration processes; and (2) PC9 cancer cells apply noticeable peri-nuclear forces on substrates. In summary, this paper presents a detailed stepwise protocol on how to utilize an integrated user-programmable system that enables automatic multi-functional imaging and analysis to elucidate YAP mechano-sensitivity. These tools open the possibility for detailed explorations of multifaceted signaling dynamics in the context of cell physiology and pathology.

DNA Genotyping Based on Isothermal Amplification and Colorimetric Detection by Consumer Electronics Devices.

The point-of-care testing of DNA biomarkers requires compact biosensing systems and consumer electronic technologies provide fascinating opportunities. Their portability, mass-produced components, and high-performance readout capabilities are the main advantages for the development of novel bioanalytical methods.This chapter describes the detection of single nucleotide polymorphisms (SNP) through methods based on user-friendly optical devices (e.g., USB digital microscope, flatbed scanner, smartphone, and DVD drive). Loop mediated isothermal amplification (LAMP) enables the required discrimination of each specific variant prior to the optical reading. In the first method, products are directly hybridized to the allele-specific probes attached to plastic chips in an array format. The second method, allele-specific primers are used, enabling the direct end-point detection based a colorimetric dyer and a microfluidic chamber chip. In both approaches, devices are employed for chip scanning.A representative application to the genotyping of a clinically relevant SNP from human samples is provided, showing the excellent features achieved. Consumer electronic devices are able to register sensitive precise measurements in terms of signal-to-noise ratios, image resolution, and scan-to-scan reproducibility. The integrated DNA-based method lead a low detection limit (100genomic DNA copies), reproducible (variation <15%), high specificity (genotypes validated by reference method), and cheap assays (<10€/test). The underlying challenge is the reliable implementation into minimal-specialized clinical laboratories, incorporating additional advantages, such as user-friendly interface, low cost, and connectivity for telemedicine needs.

Light Assisted Electro-Metallization in Resistive Switch With Optical Accessibility

An optically assisted electrically writable non-volatile nanophotonic resistive switch based on silicon is proposed with an optical readout capability. The proposed scheme also address the issue of undesired current overshoot in resistive switches. Optical assistance is provided with the blue pump light which leads to the photogenrated charge carriers in the active <inline-formula xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink"><tex-math notation="LaTeX">$TiO_{2}$</tex-math></inline-formula> layer to lower the set voltage and to improve the endurance of the device. A large hysteresis of the current loop in presence of a blue wavelength of light at lower voltages is observed with the proposed three-layered device of Ag/ <inline-formula xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink"><tex-math notation="LaTeX">$TiO_{2}$</tex-math></inline-formula> /p-Si. The electrical resistive state of the device is readout at 1550-nm of wavelength with an optical extinction ratio of 16 dB for 1 mm long device. The optical guidance with the formation (low resistance state) and dissolution (high resistance state) of conductive path filament in the active layer of <inline-formula xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink"><tex-math notation="LaTeX">$TiO_{2}$</tex-math></inline-formula> is also discussed. The proposed nanophotonic functionality can be useful in realizing ultra-compact on-chip devices for optical switching, modulation and neuromorphic computing.

A multi-functional front end readout electronics system for PET detector application

A compact, 96-ch, multi-functional and practical front-end readout electronics system for a SiPM based PET detector is developed. This electronics system is based on the latest Sigma Delta Modulation (SDM) circuit, which implements a charge-to-digital conversion (QDC) that keeps energy, timing information. In order to achieve a compact size, the system has a stacked structure including two kinds of boards, analog board and digital board. The analog board is responsible for charge integration of SDM while the digital board is for discharging feedback of the SDM circuit. Also, the digital board is applied for energy calculation, timing pickoff and data buffering and transferring. In comparison to the initial version of the SDM QDC, the input signal polarity on the electronics system is improved from negative only to both positive and negative polarities so that it can process both SiPM anode and cathode signals. Several SiPM based PET detectors are applied to validate the capability of dual polarity readout and multi-functionality. Overall, the prototype electronics system demonstrated its good performance for PET application.

Towards a two-dimensional readout of the improved CMS Resistive Plate Chamber with a new front-end electronics

As part of the Compact Muon Solenoid experiment Phase-II upgrade program, new resistive plate chambers will be installed in the region at low angle with respect to the beam collision axis, in order to improve the detection of muons with a low transverse momentum. High background conditions are expected in this region during the high-luminosity phase of the Large Hadron Collider, therefore an improved-RPC design has been proposed with a new front-end electronics to sustain a higher particle rate capability and better time resolution. A new technology is used in the front-end electronics resulting in low achievable signal detection of 1–20 fC. Crucial in the design of the improved-RPC is the capability of a two-dimensional readout in order to improve the spatial resolution, mainly motivated by trigger requirements. In this work, the first performance results towards this two-dimensional readout are presented, based on data taken on a real-size prototype chamber with two embedded readout planes with orthogonal strips.