bluuebunny/crossref_metadata_2025_split huggingface dataset:
A critical review of fabrication challenges and reliability issues in top/bottom gated MoS2field-effect transistors
Authors: Thoutam Laxman Raju , Mathew Ribu , Ajayan J , Tayal Shubham , Nair Shantikumar V 
Published: February 2023

AbstractThe voyage of semiconductor industry to decrease the size of transistors to achieve superior device performance seems to near its physical dimensional limitations. The quest is on to explore emerging material systems that offer dimensional scaling to match the silicon- based technologies. The discovery of atomic flat two-dimensional materials has opened up a completely new avenue to fabricate transistors at sub-10 nanometer level which has the potential to compete with modern silicon-based semiconductor devices. Molybdenum disulfide (MoS2) is a two-dimensional layered material with novel semiconducting properties at atomic level seems like a promising candidate that can possibly meet the expectation of Moore’s law. This review discusses the various ‘fabrication challenges’ in making MoS2based electronic devices from start to finish. The review outlines the intricate challenges of substrate selection and various synthesis methods of mono layer and few-layer MoS2. The review focuses on the various techniques and methods to minimize interface defect density at substrate/MoS2interface for optimum MoS2-based device performance. The tunable band-gap of MoS2with varying thickness presents a unique opportunity for contact engineering to mitigate the contact resistance issue using different elemental metals. In this work, we present a comprehensive overview of different types of contact materials with myriad geometries that show a profound impact on device performance. The choice of different insulating/dielectric gate oxides on MoS2in co-planar and vertical geometry is critically reviewed and the physical feasibility of the same is discussed. The experimental constraints of different encapsulation techniques on MoS2and its effect on structural and electronic properties are extensively discussed.
A single-step plasma method for rapid production of 2D, ferromagnetic, surface vacancy-engineered MoO3−x
nanomaterials, for photothermal ablation of cancer
Authors: Rahman Mizanur , Pemmaraju Deepak B , Murty Upadhyayula Suryanarayana , Phukan Sarat , Deshpande Uday P , Sathe Vasant , Kakati Mayur 
Published: February 2023

Abstract
A rapid, clean plasma-chemical technique is demonstrated here, for cost-effective, synthesis of surface vacancy engineered, 2D, molybdenum-oxide nanomaterials, during a one-step, integrated synthesis-hydrogenation process for biomedical applications. A laminar plasma beam populated with O and H radicals impinges on a molybdenum target, out of which molybdenum-oxide nanomaterials are very rapidly generated with controlled surface O vacancies. 2D, dark-blue coloured, nano-flake/ribbon like MoO3−x
is produced maximum up to 194 g h−1, the core of which still remains as stoichiometric molybdenum-oxide. These nanomaterials can get heated-up by absorbing energy from a near-infrared (NIR) laser, which enable them as photothermal therapy (PTT) candidate material for the invasive precision therapy of cancer. The surface defects endows the products with robust ferromagnetism at room temperature conditions (maximum saturation-magnetization: 6.58 emu g−1), which is order of magnitude stronger than most other vacancy engineered nanomaterials. These nanometric metal-oxides are observed to be perfectly compatible in animal physiological environment and easily dispersed in an aqueous solution even without any pre-treatment. The MoO3−x
nanomaterials are stable against further oxidation even under prolonged atmospheric exposure. In vitro experiments confirm that they have ideal efficacy for photothermal ablation of human and murine melanoma cancer at relatively lower dose. During in vivo PTT treatments, they may be manipulated with a simple external magnetic field for targeted delivery at the malignant tumours. It is demonstrated that commensurate to the neutralization of the malignant cells, the nanomaterials themselves get self-degraded, which should get easily excreted out of the body.
Haralick texture feature analysis for characterization of specific energy and absorbed dose distributions across cellular to patient length scales
Authors: Mansour Iymad R , Thomson Rowan M 
Published: February 2023

Abstract

Objective. To investigate an approach for quantitative characterization of the spatial distribution of dosimetric data by introducing Haralick texture feature analysis in this context. Approach. Monte Carlo simulations are used to generate 3D arrays of dosimetric data for 2 scenarios: (1) cell-scale microdosimetry: specific energy (energy imparted per unit mass) in cell-scale targets irradiated by photon spectra (125I, 192Ir, 6 MV); (2) tumour-scale dosimetry: absorbed dose in voxels for idealized models of 125I permanent implant prostate brachytherapy, considering ‘TG186’ (realistic tissues including 0% to 5% intraprostatic calcifications; interseed attenuation) and ‘TG43’ (water model, no interseed attenuation) conditions. Five prominent Haralick features (homogeneity, contrast, correlation, local homogeneity, entropy) are computed and trends are interpreted using fundamental radiation physics. Main results. In the cell-scale scenario, the Haralick measures quantify differences in 3D specific energy distributions due to source spectra. For example, contrast and entropy are highest for 125I reflecting the large variations in specific energy in adjacent voxels (photoelectric interactions; relatively short range of electrons), while 6 MV has the highest homogeneity with smaller variations in specific energy between voxels (Compton scattering dominates; longer range of electrons). For the tumour-scale scenario, the Haralick measures quantify differences due to TG186/TG43 simulation conditions and the presence of calcifications. For example, as calcifications increase from 0% to 5%, contrast increases while correlation decreases, reflecting the large differences in absorbed dose in adjacent voxels (higher absorbed dose in voxels with calcification due to photoelectric interactions). Significance. Haralick texture analysis provides a quantitative method for the characterization of 3D dosimetric distributions across cellular to tumour length scales, with promising future applications including analyses of multiscale tissue models, patient-specific data, and comparison of treatment approaches.
A Geant4 shielding design for the first US carbon multi-ion hybrid synchrotron facility
Authors: Dougherty Jingjing M , Bolst David , Furutani Keith M , Guatelli Susanna , Liang Xiaoying , Rosenfeld Anatoly , Beltran Chris J 
Published: February 2023

Abstract
The Mayo Clinic Florida Integrated Oncology Building will be the home of the first spot-scanning only carbon/proton hybrid therapy system by Hitachi, Ltd. It will provide proton beams up to kinetic energies of 230 MeV and carbon beams up to 430 MeV n−1 for clinical deployment. To provide adequate radiation protection, the Geant4 (v10.6) Monte Carlo toolkit was utilized to quantify the ambient dose equivalent at a 10 mm depth (H*(10)) for photons and neutrons. To perform accurate calculations of the ambient dose equivalent, three-dimensional computer-aided design files of the entire planned facility were imported into Geant4, as well as certain particle system components such as the bending magnets, fast Faraday cup, and gantry. Particle fluence was scored using 60 cm diameter spheres, which were strategically placed throughout areas of interests. Analytical calculations were performed as first-pass design checks. Major shielding slabs were optimized using Geant4 simulations iteratively, with more than 20 alternative designs evaluated within Geant4. The 430 MeV n−1 carbon beams played the most significant role in concrete thickness Requirements. The primary wall thickness for the carbon fixed beam room is 4 meters. The presence of the proton gantry structure in the simulation caused the ambient dose equivalent to increase by around 67% at the maze entrance, but a decrease in the high energy beam transport corridor. All shielding primary and secondary goals for clinical operations were met per state regulation and national guidelines.
Investigating the potential contribution of inter-track interactions within ultra-high dose-rate proton therapy
Authors: Thompson Shannon J , Prise Kevin M , McMahon Stephen J 
Published: February 2023

Abstract

Objective. Laser-accelerated protons offer an alternative delivery mechanism for proton therapy. This technique delivers dose-rates of ≥109 Gy s−1, many orders of magnitude greater than used clinically. Such ultra-high dose-rates reduce delivery time to nanoseconds, equivalent to the lifetime of reactive chemical species within a biological medium. This leads to the possibility of inter-track interactions between successive protons within a pulse, potentially altering the yields of damaging radicals if they are in sufficient spatial proximity. This work investigates the temporal evolution of chemical species for a range of proton energies and doses to quantify the circumstances required for inter-track interactions, and determine any relevance within ultra-high dose-rate proton therapy. Approach. The TOPAS-nBio Monte Carlo toolkit was used to investigate possible inter-track interactions. Firstly, protons between 0.5 and 100 MeV were simulated to record the radial track dimensions throughout the chemical stage from 1 ps to 1 μs. Using the track areas, the geometric probability of track overlap was calculated for various exposures and timescales. A sample of irradiations were then simulated in detail to compare any change in chemical yields for independently and instantaneously delivered tracks, and validate the analytic model. Main results. Track overlap for a clinical 2 Gy dose was negligible for biologically relevant timepoints for all energies. Overlap probability increased with time after irradiation, proton energy and dose, with a minimum 23 Gy dose required before significant track overlap occurred. Simulating chemical interactions confirmed these results with no change in radical yields seen up to 8 Gy for independently and instantaneously delivered tracks. Significance. These observations suggest that the spatial separation between incident protons is too large for physico-chemical inter-track interactions, regardless of the delivery time, indicating such interactions would not play a role in any potential changes in biological response between laser-accelerated and conventional proton therapy.
Adaptive tetrahedral interpolation for reconstruction of uneven freehand 3D ultrasound
Authors: Wang Yifan , Fu Tianyu , Wu Chan , Fan Jingfan , Song Hong , Xiao Deqiang , Lin Yucong , Liu Fangyi , Yang Jian 
Published: February 2023

Abstract

Objective. Freehand 3D ultrasound volume reconstruction has received considerable attention in medical research because it can freely perform spatial imaging at a low cost. However, the uneven distribution of the original ultrasound images in space reduces the reconstruction effect of the traditional method. Approach. An adaptive tetrahedral interpolation algorithm is proposed to reconstruct 3D ultrasound volume data. The algorithm adaptively divides the unevenly distributed images into numerous tetrahedrons and interpolates the voxel value in each tetrahedron to reconstruct 3D ultrasound volume data. Main results. Extensive experiments on simulated and clinical data confirm that the proposed method can achieve more accurate reconstruction than six benchmark methods. Specifically, the averaged interpolation error at the gray level can be reduced by 0.22–0.82, and the peak signal-to-noise ratio and the mean structure similarity can be improved by 0.32–1.83 dB and 0.01–0.05, respectively. Significance. With the parallel implementation of the algorithm, one 3D ultrasound volume data with size 279 × 279 × 276 can be reconstructed from 100 slices 2D ultrasound images with size 200 × 200 at 1.04 s. Such a quick and accurate approach has practical value in medical research.
Deep learning based automatic contour refinement for inaccurate auto-segmentation in MR-guided adaptive radiotherapy
Authors: Ding Jie , Zhang Ying , Amjad Asma , Sarosiek Christina , Dang Nguyen Phuong , Zarenia Mohammad , Li X Allen 
Published: February 2023

Abstract

Objective. Fast and accurate auto-segmentation is essential for magnetic resonance-guided adaptive radiation therapy (MRgART). Deep learning auto-segmentation (DLAS) is not always clinically acceptable, particularly for complex abdominal organs. We previously reported an automatic contour refinement (ACR) solution of using an active contour model (ACM) to partially correct the DLAS contours. This study aims to develop a DL-based ACR model to work in conjunction with ACM-ACR to further improve the contour accuracy. Approach. The DL-ACR model was trained and tested using bowel contours created by an in-house DLAS system from 160 MR sets (76 from MR-simulation and 84 from MR-Linac). The contours were classified into acceptable, minor-error and major-error groups using two approaches of contour quality classification (CQC), based on the AAPM TG-132 recommendation and an in-house classification model, respectively. For the major-error group, DL-ACR was applied subsequently after ACM-ACR to further refine the contours. For the minor-error group, contours were directly corrected by DL-ACR without applying an initial ACM-ACR. The ACR workflow was performed separately for the two CQC methods and was evaluated using contours from 25 image sets as independent testing data. Main results. The best ACR performance was observed in the MR-simulation testing set using CQC by TG-132: (1) for the major-error group, 44% (177/401) were improved to minor-error group and 5% (22/401) became acceptable by applying ACM-ACR; among these 177 contours that shifted from major-error to minor-error with ACM-ACR, DL-ACR further refined 49% (87/177) to acceptable; and overall, 36% (145/401) were improved to minor-error contours, and 30% (119/401) became acceptable after sequentially applying ACM-ACR and DL-ACR; (2) for the minor-error group, 43% (320/750) were improved to acceptable contours using DL-ACR. Significance. The obtained ACR workflow substantially improves the accuracy of DLAS bowel contours, minimizing the manual editing time and accelerating the segmentation process of MRgART.
Activation of vibrational-induced CO2 dissociation in cold non-equilibrium plasma
Authors: Pietanza Lucia Daniela , Colonna Gianpiero , Capitelli Mario 
Published: February 2023

Abstract
The activation of vibrational-induced dissociation of CO2 in cold non-equilibrium plasma discharges is investigated by means of a 0D self-consistent kinetic model, which, with a state-to-state approach, is able to calculate the CO2 vibrational distribution function (vdf) of the asymmetric mode levels, the electron energy distribution function and the corresponding vibrational-induced and electron impact CO2 dissociation rates. The conditions for the onset of such activation are linked to the achievement of a sufficiently high CO2 vibrational excitation characterized by the presence of a non-equilibrium plateau in the CO2 vdf, resulting from the combined effect of electron–vibrational and vibrational–vibrational collisions, which, by overpopulating the higher vibrational levels, enhances dissociation. Such non-equilibrium conditions are maximized at lower gas temperature, lower pressure and higher power density values. In particular, for the power density, an activation threshold value can be obtained from simulations and its dependence on the gas temperature and pressure can be investigated. The dependence of the maximum vibrational temperature reached at the end of the discharge as a function of the gas temperature and pressure is also analyzed. A satisfactory agreement from our simulation results with the Kotov’s criterion for vibrational activation has been found.
Dense plasma focus: different cathode geometries and their influence on the hard x-ray production
Authors: Barbaglia M , Giovachini R , Milanese M 
Published: February 2023

Abstract
Using the plasma-focus device called PACO (Plasma Auto COnfinado), three types of cathodes were experimentally investigated to evaluate their influence on the hard x-ray production. Two barred cathodes with diameters of 82 mm and 90 mm and one cathode without any specific structure (i.e. the current sheet flowed freely on the radial axis) were tested for this work. In every experiment, the capacitor bank was charged to 31 kV. The gas used was deuterium in the pressure range of 0.5 mbar and 3.0 mbar. The production of neutrons and hard x-ray simultaneously was not detected outside this range. Using the cathode with a diameter of 82 mm the hard x-ray production was maximized.
Modeling and analysis of frequency-variable 2–2 cement-based piezoelectric transducers
Authors: Lan Chengming , Wen Lijie , Wang Jianjun , Li Weijie , Tang Lihua 
Published: February 2023

Abstract
The 2–2 cement-based piezoelectric transducers can be used as high-performance actuators and sensors. However, the existing designs with fixed electromechanical properties cannot meet some special application requirements, such as the tuning working frequency to achieve high precision monitoring purpose. To address this issue, a type of frequency-variable 2–2 cement-based piezoelectric transducers is proposed in this paper. Theoretical models of the proposed transducer are established, and the analytical solutions of its longitudinal vibration are obtained. The theoretical models are verified by comparing their results with those of the existing literature for some special examples, and with the finite element results for a special case. In addition, the effects of the tuning resistance, the ratio of piezoelectric layer numbers between the active and passive elements, the electrical connections of piezoelectric layers, and the total number of piezoelectric layers on the electromechanical properties of transducer are discussed. It is demonstrated that the proposed frequency-variable 2–2 cement-based piezoelectric transducers can obtain a large tunable bandwidth by adjusting the appropriate ratio of piezoelectric layer numbers between the active and passive elements and their electrical connections, which provides a theoretical basis for designing and optimizing this type of transducers.
A prediction method for the screening current induced field in HTS magnets based on time series models
Authors: Wang Mingyang , Meng Xuan’ang , Cai Tiantian , Sheng Jie , Li Zhuyong , Hong Zhiyong , Jin Zhijian 
Published: February 2023

Abstract
Due to their special electromagnetic properties, high temperature superconducting (HTS) conductors have become a potential solution for ultra-high field magnet and energy storage applications. However, the screening current induced field (SCIF) has been demonstrated to be the main limitation of high field HTS magnets in actual applications. Based on time series models, this paper presents a prediction method of SCIF to support the design and application of HTS magnets. First, we analyze the data characteristics of the SCIF hysteresis loop. The simulated dataset is prepared for two typical magnet structures: single pancake and solenoid. Then, time series models are proposed for the SCIF prediction. Through intuitive analysis and evaluation metrics, the training performance of time series models is confirmed. After a discussion of hyper-parameters and dimension reduction, the optimized prediction performance is obtained for the SCIF hysteresis loop. In conjunction with the iterative prediction mode, we finally achieve a feasible and effective prediction method of SCIF for HTS magnets. This will provide a tool and research strategy to support the general finite element method.
FPGA implementation, controls and synchronization of autonomous Josephson junction jerk oscillator
Authors: Dongmo Eric Donald , Ramadoss Janarthanan , Tchamda André Rodrigue , Sone Michael Ekonde , Rajagopal Karthikeyan 
Published: February 2023

Abstract
This paper reports the field programmable gate array (FPGA) implementation of an autonomous Josephson junction jerk oscillator (AJJJO) and the investigated coexisting and chaotic attractors besteered, with different synchronization achieved. AJJJO displays bistability, megastability, and coexistence between limit cycle and self-excited chaotic attractors, which is validated by the FPGA implementation. The elimination of chaotic dynamics exhibited by AJJJO was done by using a double single controller via numerical simulations. The coexisting attractors between limit cycle and self-excited chaotic attractors are destroyed and besteered to the wanted path via the linear augmentation control method. Moreover, controllers are employed to achieve the difference synchronization of three identical coupled chaotic AJJJOs resulting from various starting conditions. Finally, numerical simulations of three identical coupled chaotic AJJJOs indicate the effectiveness of the difference synchronization.
Verification and development of a metamaterial with large bandwidth smooth transmission properties for the thermal properties sensing of Xuan paper
Authors: Wu Dan , Wu Yu , Huang Ge , Zhong Min 
Published: February 2023

Abstract
Metamaterial sensors are widely used because of their rich resonance behaviors. However, due to the dependence on resonance properties, many metamaterial sensors are difficult to be applied in measurement of the stationary thermal properties of Xuan paper samples in a wide frequency range. Many important properties of Xuan paper samples are related to thermal resonance properties,. such as folding resistance, tensile strength, ink-run property, whiteness, dry heat and wet heat aging. Here, a metamaterial sensor with smooth transmission performance in the operating frequency band is designed and fabricated. In experiments, by increasing temperature, the time for the thermal response current of the Xuan paper samples to reach the peak value is significantly reduced, and the average peak value is increased. The heat conduction of the Xuan paper samples is increased and the thermal resistance is reduaced. When the thickness of the Xuan paper sample is gradually increased, the time required for the thermal response current to reach the peak value is gradually increased and the average peak value is decreased. When the concentration of alum gelatin solution applied on the surface of the Xuan paper sample is gradually increased, the corresponding thermal response current is enhanced, and the time required to reach the peak is significantly reduced. The results show that the metamaterial sensor can be used to measure the thermal properties of Xuan paper samples.