bluuebunny/crossref_metadata_2025 huggingface dataset:
The Burden of Anabolic Androgenic Steroid-Induced Gynecomastia
Authors: Beniwal Meenu , Singh Kuldeep , Singh Paritev , Sharma Abhishek , Beniwal Sonu
Published: July 2023

Introduction Gynecomastia is benign proliferation of male breast tissue that can be idiopathic or secondary to hormonal imbalance. Consumption of steroids plays a major role in the development of gynecomastia. The increased consumption of anabolic androgenic steroid (AAS) in youngsters to boost the physical strength and improve appearance is associated with increased prevalence of gynecomastia. True estimation of AAS-associated gynecomastia is difficult to calculate and prone to underestimation because of low social acceptance. Accurate estimation is required to assess future healthcare, for prevention and to give appropriate treatment.

Aims and Objectives The aim of this study was to calculate the steroid consumption in gynecomastia patients accurately so that appropriate treatment can be given and their response to treatment could be analysed.

Methods This is a prospective study done in a tertiary care hospital from June 2019 to June 2022. All the gynecomastia patients treated during this period in Burns & Plastic Surgery Department of PGIMS Rohtak were included in the study. Patient's detailed history was recorded and also after 3 months of surgery patients were again enquired about their history to record any change.

Results Real prevalence of AAS-associated gynecomastia (39.19%) was much higher than that recorded in preoperative period (4.05%). Also, AAS users were having higher body mass index and a greater proportion of patients were bodybuilders.

Conclusion Patients with high body mass index, athletic body, and history of recent weight gain should raise the suspicion of anabolic steroid intake. Surgery is not always indicated in AAS-associated gynecomastia. If gynecomastia persisted, surgery necessitates and it involves meticulous intraoperative hemostasis and careful glandular excision to minimize recurrence and achieve low complication rates.
Management of Gastric Varices: IR Perspective
Authors: Dervishi Mario , Sutter Christopher , Varma Rakesh K.
Published: July 2023

Gastric varices are a sequela of portal hypertension. If left untreated, life-threatening bleeding can occur. While endoscopic treatment is traditionally considered as a first-line interventional option, endovascular techniques have emerged to become the superior option in certain clinical scenarios, either as a first-line therapy or a salvage therapy. Endovascular techniques for managing gastric varices include transjugular intrahepatic portosystemic shunt (TIPS) placement, balloon-occluded retrograde transvenous obliteration (BRTO), coil, and plug-assisted retrograde transvenous obliteration, as well as a combination of both. Studies have shown that endovascular techniques can effectively control bleeding from gastric varices, with high success rates and low complication rates, and significantly reduce recurrence. TIPS placement has shown to be more effective in controlling bleeding from gastroesophageal varices, while BRTO, coil, or plug-assisted embolizations are more suitable for patients with isolated gastric varices. Endovascular interventions are a valuable option for managing gastric varices, especially in patients who are not candidates for endoscopic treatment or who have failed previous endoscopic interventions. In this two-part series editorial, we aim to initially review the complex anatomy and classification of gastric varices, medical management, and current endovascular interventional techniques, and how they compare with one another. In part 2, we draw a parallel between endovascular versus endoscopic techniques, and highlight and critically review current literature as it pertains to gastric variceal management.
Two Puzzling Cases of Headache: A Case Series
Authors: Singh Jasmine , Azad Chandrika
Published: July 2023

Migraine and epilepsy are important causes of morbidity in adolescents and young adults. Mostly the diagnosis is readily made by using the predefined criteria. However, in extremely rare cases, children who present with typical symptoms of migraine with aura or familial hemiplegic migraine might have an underlying etiology of epilepsy. We hereby present the case of two children who presented with migraine-like symptoms but on detailed workup revealed an underlying epilepsy. Both patients responded to antiepileptic medications. These cases highlight the importance of a detailed history and comprehensive investigation plan for such patients to prevent erroneous diagnosis and migraine prophylaxis.
Hostile Hemodynamics in Distal Stent Graft–Induced New Entry Prior to Aortic Rupture: A Comparison of Transient versus Steady-State CFD Simulations
Authors: Osswald Anja , Tsagakis Konstantinos , Demircioglu Ender , Weymann Alexander , Zubarevich Alina , Ruhparwar Arjang , Karmonik Christof
Published: July 2023

Background Computational fluid dynamics (CFD) simulations model blood flow in aortic pathologies. The aim of our study was to understand the local hemodynamic environment at the site of rupture in distal stent graft–induced new entry (dSINE) after frozen elephant trunk with a clinically time efficient steady-flow simulation versus transient simulations.

Methods Steady-state simulations were performed for dSINE, prior and after its development and prior to aortic rupture. To account for potential turbulences due geometric changes at the dSINE location, Reynolds-averaged Navier–Stokes equations with the realizable k-ε model for turbulences were applied. Transient simulations were performed for comparison. Hemodynamic parameters were assessed at various locations of the aorta.

Results Post-dSINE, jet-like flow due to luminal narrowing was observed which increased prior to rupture and resulted in focal neighbored regions of high and low wall shear stress (WSS). Prior to rupture, aortic diameter at the rupture site increased lowering WSS at the entire aortic circumference. Concurrently, WSS and turbulence increased locally above the entry tear at the inner aortic curvature. Turbulent kinetic energy and WSS elevation in the downstream aorta demonstrated enhanced stress on the native aorta. Results of steady-state simulations were in good qualitative agreement with transient simulations.

Conclusion Steady-flow CFD simulations feasible at clinical time scales prior to aortic rupture reveal a hostile hemodynamic environment at the dSINE rupture site in agreement with lengthy transient simulations. Consequently, our developed approach may be of value in treatment planning where a fast assessment of the local hemodynamic environment is essential.
Collaboration and cooperation systems to prevent suicide among children in Japan: effective use of the Observe–Orient–Decide–Act loop
Authors: Okada Michiyo , Suzue Takeshi , Katayama Harumi , Nakadoi Yoshihiro , Fujikawa Ai
Published: July 2023

Suicide among school-age children is a serious issue in Japan, exacerbated by the coronavirus disease 2019 pandemic. Collaboration and cooperation between schools—where children spend much of their time—and medical/welfare services are indispensable. However, teachers are overworked, and intensified stress levels have led to high absenteeism. We propose the effective use of the Observe–Orient–Decide–Act (OODA) loop for timely collaboration and cooperation between schools and medical institutions to manage high-risk children as a measure to prevent suicide. We administered questionnaires to 205 teachers who worked with children, nurses, welfare professionals, and school counsellors in schools and related facilities; 171 respondents with valid responses were included. We examined their self-rated health, attitudes towards the OODA loop, levels of depressive symptoms, satisfaction/dissatisfaction with the current status of collaboration and cooperation, and reasons for this. When we compared those satisfied/dissatisfied with the current status of collaboration and cooperation, we found no significant differences in the level of depressive symptoms, but the self-rated health of the latter was poorer. We identified three factors in the attitude survey on the OODA loop—flexible and independent situational assessment, group monitoring and sharing, and self-monitoring—and those who were dissatisfied showed lower scores for all items. We classified the reasons into three categories—details of collaboration and cooperation, methods of collaboration and cooperation, and organisations for collaboration and cooperation—revealing marked differences. The level of satisfaction with the current status of collaboration and cooperation was correlated with the level of mental health. Satisfied participants were more positive about adopting OODA perspectives. Raising awareness of the OODA concept among teaching personnel, creating an organisational structure, establishing systems for appropriate and organic collaboration between schools and medical/welfare institutions, and reviews by external institutions are necessary to effectively use the OODA loop.
Deep ensemble inverse model for image-based estimation of solar cell parameters
Authors: Battaglia M. , Comi E. , Stadelmann T. , Hiestand R. , Ruhstaller B. , Knapp E.
Published: July 2023

Physical models can help improve solar cell efficiency during the design phase and for quality control after the fabrication process. We present a data-driven approach to inverse modeling that can predict the underlying parameters of a finite element method solar cell model based on an electroluminescence (EL) image of a solar cell with known cell geometry and laser scribed defects. For training the inverse model, 75 000 synthetic EL images were generated with randomized parameters of the physical cell model. We combine 17 deep convolutional neural networks based on a modified VGG19 architecture into a deep ensemble to add uncertainty estimates. Using the silicon solar cell model, we show that such a novel approach to data-driven statistical inverse modeling can help apply recent developments in deep learning to new engineering applications that require real-time parameterizations of physical models augmented by confidence intervals. The trained network was tested on four different physical solar cell samples, and the estimated parameters were used to create the corresponding model representations. Resimulations of the measurements yielded relative deviations of the calculated and the measured junction voltage values of 0.2% on average with a maximum of 10%, demonstrating the validity of the approach.
Arrested spinodal decomposition of the screened symmetric restricted primitive model
Authors: Benitez-Camacho Nohely , Olais-Govea José Manuel , López-Flores Leticia , Ruiz-Estrada Honorina
Published: July 2023

Amorphous solids, such as glasses and gels, arise as the asymptotic limit of non-equilibrium and irreversible relaxation aging processes. These amorphous solids form when the system is suddenly and deeply quenched in the dynamic arrest region. We use the non-equilibrium self-consistent generalized Langevin equation (NE-SCGLE) theory to investigate the formation of such structures via arrested spinodal decomposition in the screened symmetric restricted primitive model. We propose a direct correlation function that allows us to derive an expression for the functional derivative of the chemical potential, which serves as the necessary input in the NE-SCGLE theory. By analyzing the asymptotic localization length and the asymptotic characteristic length, we identify different classes of dynamic arrest states as a function of the density and the final quench temperature. The system features simultaneously attractive and repulsive interactions, resulting in different arrested regions in the non-equilibrium phase diagram for a given screened parameter: (i) ionic glasses, (ii) electrostatic gels, and (iii) attractive glasses. Finally, by collapsing the asymptotic effective structure factors at a typical fractal dimension of df = 3, we confirm the formation of gels slightly above the glass-gel transition in the arrested phase diagram.
The investigation of a portable solar telescope with a high gain metamaterial antenna for F10.7 radio flux measurement
Authors: Zhao Zhenyu , Liu Haiwen , Dong Liang , Gao Mengying , Kuang Jiaxin , Yan Fabao
Published: July 2023

A high gain and high aperture efficiency metamaterial (MTM) antenna is applied to a solar telescope in this paper. First, a portable solar telescope including the MTM antenna and a receiving system is presented. Next, the theory of the MTM antenna is proposed and analyzed based on the ray-tracing model. The designed MTM antenna is composed of a dual circularly polarized Fabry–Pérot resonant antenna (FPRA) and four phase correction metasurfaces (PCMs). The proposed PCMs act as the reflection surface and the phase correction surface at the same time. Every PCM consists of 2 × 18 optimized artificial magnetic conductor (AMC) units. To solve the parallel incidence and narrow bandwidth problems of AMC units, a nonuniform partially reflective surface is designed. Compared with traditional FPRA, the proposed MTM antenna has an increase in peak gain of 37.5% and an aperture efficiency of 11.4%. Then, a receiving system composed of the receiver, equatorial mount, data acquisition module, and display module is presented for solar radio signal processing. Finally, the designed MTM antenna and solar telescope are simulated and measured. A good agreement between the simulation and measurement is observed and can be used to verify this design.
The effect of thixotropy on the yield transition in reversible, colloidal gels
Authors: Nikoumanesh E. , Poling-Skutvik R.
Published: July 2023

Thixotropic yield-stress fluids (TYSFs) are a unique class of materials whose properties are affected by both shear rate and shear history. When sheared, these materials undergo a transition from an elastic solid to a viscoelastic fluid, which is accompanied by a structural transition that slowly recovers upon the cessation of shear. The strong interdependence between structure, dynamics, and rheological properties in TYSFs make it challenging to identify the fundamental physics controlling these phenomena. In this study, we vary the ionic strength of a suspension of cellulose nanocrystals (CNC) to generate model TYSFs with tunable moduli and thixotropic kinetics. We use a novel rheological protocol—serial creep divergence—to identify the physics underlying the yield transition and recovery of CNC gels. Our protocol identifies a critical transition that bifurcates the solid-like and fluid-like regimes of the gels to precisely determine the yield stress of these materials even in the presence of thixotropic effects. Additionally, the thixotropic kinetics collapse onto a single master curve, which we fit to a transient solution to a coupled diffusion–aggregation model. Our work thereby identifies the underlying physicochemical mechanisms driving yielding and thixotropic recovery in attractive colloidal gels.
Numerical simulations of cavitating water jet by an improved cavitation model of compressible mixture flow with an emphasis on phase change effects
Authors: Onishi Taihei , Peng Yanbo , Ji Hong , Peng Guoyi
Published: July 2023

Focusing on cavitation phenomena caused by high-speed submerged water jets, this paper presents an improved cavitation model for a compressible fluid mixture based on a concise estimation of fluid compressibility that considers phase change effects. The homogeneous two-phase flow assumption is adopted, and the gas phase is assumed to consist of vapor and non-condensable components. Equations of state for a pure liquid and an ideal gas are employed to evaluate the compressibility of the liquid and non-condensable components, and the compressibility of the vapor is treated semi-empirically as a constant. The model is embedded in an unsteady Reynolds-averaged Navier–Stokes solver, with the realizable k-ε model employed to evaluate the eddy viscosity. The turbulent cavitating flow caused by an impulsively started submerged water jet is treated. The pattern of periodic cavitation cloud shedding is acceptably captured, and the mass flow rate coefficient and its fluctuation frequency evaluated by simulations agree with the experimental results well. The validity of the proposed method is confirmed. The results reveal that cavitation occurs when pin/Pin reaches 0.65 and fluid flow begins to pulsate. In the well-developed stage, the leading cavitation cloud and a subsequent cloud are successively shed downstream, and this process is repeated. The subsequent cloud catches the leading cloud, and they coalesce in the range x/d≈ 2–3. The pressure fluctuations concentrate in the range of x/d≈2–5 corresponding to the periodic shedding of cavitation clouds. The mass flow rate coefficient pulsates from 0.59–0.66 under the effect of cavitation.
A MIMO approach for longitudinal sensing and control noise projections of Advanced Virgo gravitational wave detector
Authors: Tapia San Martín E N , Valentini M , Bersanetti D , Was M , Maggiore R , van Dael M , Perry J W , Swinkels B L , Mantovani M , Freise A , Tacca M
Published: July 2023

So far, the sensitivity of gravitational-wave (GW) detectors, in the low-frequency and mid-frequency regions of its bandwidth, has been limited by technical noises. The re-injection of sensing and control noises can be one of the main limitations. After the end of the third observing run O3, in preparation for the fourth observing run O4, an upgrade phase started among all the km-scale GW detectors, namely LIGO, Virgo and KAGRA, with the aim of improving their sensitivity. In particular, for the case of Advanced Virgo, one of the most significant upgrades is the installation of a signal recycling (SR) mirror, introducing the SR cavity. The main target of this SR mirror is to shape the sensitivity curve of the detector. The installation of a SR mirror adds an extra optical cavity and, thus, extra DoFs (longitudinal and angular), that should be controlled to keep its working point, ultimately increasing the complexity of the whole control strategy. In order to have an accurate description of the interferometer, we have implemented a multiple-input multiple-output (MIMO) model in the frequency domain. The target of this paper, after showing the Advanced Virgo configuration for the next observing run, is to describe the control scheme used for the main longitudinal degrees of freedom using a MIMO approach. In particular, we detail a useful matrix representation for the modeled system. Finally, we use the implemented model to project the sensing and control noises on the sensitivity curve. Following the obtained results, we propose noise subtraction filters to achieve the low control noise target in the low-frequency region of the sensitivity curve. Additionally, using this model, we have implemented the core of a noise budget tool, which will allow to estimate the contribution of all the known sources of noise on the measured sensitivity.
On the stability of homogeneous equilibria in the Vlasov–Poisson system on R3
Authors: Ionescu A D , Pausader B , Wang X , Widmayer K
Published: July 2023

The goal of this article is twofold. First, we investigate the linearized Vlasov–Poisson system around a family of spatially homogeneous equilibria inR3(the unconfined setting). Our analysis follows classical strategies from physics (Binney and Tremaine 2008Galactic Dynamics(Princeton University Press); Landau 1946Acad. Sci. USSR. J. Phys.1025–34; Penrose 1960Phys. Fluids3258–65) and their subsequent mathematical extensions (Bedrossianet al2022SIAM J. Math. Anal.544379–406; Degond 1986Trans. Am. Math. Soc.294435–53; Glassey and Schaeffer 1994Transp. Theory Stat. Phys.23411–53; Grenieret al2021Math. Res. Lett.281679–702; Han-Kwanet al2021Commun. Math. Phys.3871405–40; Mouhot and Villani 2011Acta Math.20729–201). The main novelties are a unified treatment of a broad class of analytic equilibria and the study of a class of generalized Poisson equilibria. For the former, this provides a detailed description of the associated Green’s functions, including in particular precise dissipation rates (which appear to be new), whereas for the latter we exhibit explicit formulas. Second, we review the main result and ideas in our recent work (Ionescuet al2022 (arXiv:2205.04540)) on the full global nonlinear asymptotic stability of the Poisson equilibrium inR3.
Estimation of the cell membrane permeability for gas transport from surface pH measurements
Authors: Bocchinfuso A , Calvetti D , Somersalo E
Published: July 2023

Bayesian particle filters (PFs) are a viable alternative to sampling methods such as Markov chain Monte Carlo methods to estimate model parameters and related uncertainties when the forward model is a dynamical system, and the data are time series that depend on the state vector. PF techniques are particularly attractive when the dimensionality of the state space is large and the numerical solution of the dynamical system over the time interval corresponding to the data is time consuming. Moreover, information contained in the PF solution can be used to infer on the sensitivity of the unknown parameters to different temporal segments of the data. This, in turn, can guide the design of more efficient and effective data collection procedures. In this article the PF method is applied to the problem of estimating cell membrane permeability to gases from pH measurements on or near the cell membrane. The forward model in this case comprises a spatially distributed system of coupled reaction–diffusion differential equations. The high dimensionality of the state space and the need to account for the micro-environment created by the pH electrode measurement device are additional challenges that are addressed by the solution method.
Metamaterial as perfect absorber for high sensitivity refractive index based biosensing applications at infrared frequencies
Authors: Mostufa Shahriar , Yari Parsa , Rezaei Bahareh , Xu Kanglin , Sun Jiajia , Shi Zongqian , Wu Kai
Published: July 2023

In this paper, we introduce a novel design of a metamaterial unit cell absorber, which is based on a metal/insulator/metal sandwich structure. The design is subjected to comprehensive finite element method computational analysis to ensure accurate and reliable results. The proposed metamaterial sandwich structure demonstrates exceptional absorption performance, achieving a nearly perfect absorption rate of 99.996% at the resonance infrared frequency of 39.8 THz. To provide a detailed theoretical explanation of nearly perfect absorption, we employ the effective medium theory, impedance matching, and field distribution analysis. Additionally, we have optimized the structural parameters of the sensor to maximize its absorption peak. This includes optimizing the thickness of the gold (Au) layer (from 0.03 to 0.28 μm), the distance between the L shape corners (from 0.60 to 0.90 μm), and the thickness of SiC dielectric spacer (from 0.20 to 0.45 μm). Furthermore, we showcase the remarkable sensitivity of the proposed metamaterial unit cell in detecting subtle changes in the refractive index through the implementation of a sensing medium setup in our model. Remarkably, we achieve a frequency shift sensitivity of 3.74 THz/RIU, along with a quality factor of 10.33, for a wide range of refractive indices (1.0–2.0). Moreover, for cancer detection, we attain a sensitivity of 3.5 THz/RIU. These findings highlight the exceptional performance of our approach in accurately detecting changes in refractive index, making it a promising candidate for various sensing applications. The novelty of our work lies in the design of a metamaterial unit cell structure. This configuration exhibits several noteworthy features, including wide incident angle (

θ

) coverage up to 60°, polarization insensitivity, exceptional frequency shift sensitivity, high absorption peaks across a wide range of refractive indices, and the ability to distinguish cancer cells from healthy ones.
Mid-infrared pyroelectric detector with metasurface electrode for broadband enhanced absorption
Authors: Zou Yongtu , Chen Shanri , Sun Jigeng , Zhou Shaolin
Published: July 2023

Pyroelectric photodetectors have continuously been an attractive candidate due to their noncryogenic and easy-to-fabricate specifics. Because the detectivity or resolution of the pyroelectric detector is closely related to the absorptivity to incident radiation, we propose a scheme for a metasurface-based pyroelectric detector (MPPD) by constructing its top electrode with an absorptive metasurface composed of nanogrid-patch units. The resonance modes of Fabry–Perot cavity, magnetic dipole and electric dipole are collectively leveraged for the mid-infrared MPPD with optimal broadband absorption plus three absorptive peaks at 3.13 μm, 3.94 μm and 4.8 μm. The mechanisms and field distributions of these resonance peaks are intensively explored and verified for configuration of the metasurface top electrode with optimized geometries. Finally, our scheme achieves an average absorptivity of 94.2% in the mid-infrared range of 3–5 μm, with its thermal response enhanced by 2.6 times that results in a significantly improved pyroelectric current for the detector.
Atomistic designing of 2D quantum materials heterostructures CdF/CrI3 for Berry curvature driven tunable intrinsic anomalous Hall state
Authors: Sadhukhan Surasree , Kanungo Sudipta
Published: July 2023

The coupling between topology and magnetism can explore rich physics with fundamental interest. Passing through the phase of Bismuth-based topological insulators magnetized by the 3d/4f transition metal doping, currently the fabrication of quantum heterostructures by suitable new-generation 2D materials, has emerged as a prospective alternative. Following the current trends, the present investigation deals with the atomistic designing and investigation of the quantum heterostructures of the newly predicted massive Dirac semimetal CdF and well-known layered ferromagnetic insulator CrI3 using the first-principles density functional theory calculations supplemented by the low energy tight-binding model Hamiltonian. The designed strategy ensures the lattice mismatch should be within the permissible range. We have addressed the physical characteristics of heterostructures in terms of the non-trivial topological band inversion between Cd-5s and I-2p orbitals. Proximity effect induces magnetic interactions, breaks the time-reversal symmetry at the interface, and leads to Berry curvature-driven tunable intrinsic anomalous Hall conductance (AHC) at the Fermi energy. Our analysis reveals the electrons with high Fermi velocity (

≈

106 m s−1) in the heterostructures and the band topology at the Fermi level can be tuned effectively using very small external gate voltage or homogeneous electric field. Our investigation can open up new avenues for designing new topological phases in the heterostructure community and possible tailoring routes of the intrinsic AHC in moderate temperature.
Fault identification method based on generative adversarial network in distributed acoustic sensing
Authors: Shang Ying , Wang Jiawen , Huang Sheng , Qu Shuai , He Qiujie , Wang Meikun , Li Di , Wang Weitao , Liu Guangqiang , Yao Chunmei , Wang Chen
Published: July 2023

With the rapid development of machine learning and deep learning, neural-network-based pattern recognition techniques have become a trend for distributed acoustic sensing (DAS) systems. However, in some cases, certain types of data are difficult to obtain, which leads to imbalanced sample sets. To solve this problem, a data augmentation method based on a generative adversarial network is proposed in this study. First, normal operation samples, including the normal operation training and testing sets are collected using the DAS system. The cyclegan algorithm is then used to generate fault operation samples, a part of which can be selected as the fault operation training set, whereas the others can be viewed as the fault operation testing set. Furthermore, an effective method of data augmentation, called k-means clustering-synthetic minority oversampling technique deep convolutional generative adversarial network, is proposed to enhance the fault operation training set. Finally, the proposed method is applied to the on-load tap-changer, and the experimental results show that the average accuracy of the validation set for the classification task can reach 97%.
Granular metals with SiN
x
dielectrics
Authors: Gilbert Simeon J , Meyerson Melissa L , Kotula Paul G , Rosenberg Samantha G , Kmieciak Thomas G , McGarry Michael P , Siegal Michael P , Biedermann Laura B
Published: July 2023

Understanding and controlling nanoscale interface phenomena, such as band bending and secondary phase formation, is crucial for electronic device optimization. In granular metal (GM) studies, where metal nanoparticles are embedded in an insulating matrix, the importance of interface phenomena is frequently neglected. We demonstrate that GMs can serve as an exemplar system for evaluating the role of secondary phases at interfaces through a combination of x-ray photoemission spectroscopy (XPS) and electrical transport studies. We investigated SiN
x
as an alternative to more commonly used oxide-insulators, as SiN
x
-based GMs may enable high temperature applications when paired with refractory metals. Comparing Co-SiN
x
and Mo-SiN
x
GMs, we found that, in the tunneling-dominated insulating regime, Mo-SiN
x
had reduced metal-silicide formation and orders-of-magnitude lower conductivity. XPS measurements indicate that metal-silicide and metal-nitride formation are mitigatable concerns in Mo-SiN
x
. Given the metal-oxide formation seen in other GMs, SiN
x
is an appealing alternative for metals that readily oxidize. Furthermore, SiN
x
provides a path to metal-nitride nanostructures, potentially useful for various applications in plasmonics, optics, and sensing.
Investigating on sensing mechanism of MoS2-FET biosensors in response to proteins
Authors: Ji Ziheng , Wei Junqing , Luo Fengting , Liu Zihao , Lu Haotian , Chen Ruibing , Wang Yong , Qin Guoxuan
Published: July 2023

Field-effect transistor (FET) biosensors based on two-dimensional materials have gained extensive attention due to their high sensitivity, label-free detection capability, and fast response. Molybdenum disulfide (MoS2), with tunable bandgap, high surface-to-volume ratio, and smooth surface without dangling bonds, is a promising material for FET biosensors. Previous reports have demonstrated the fabrication of MoS2-FET biosensors and their high sensitivity detection of proteins. However, most prior research has focused on the realization of MoS2-FETs for detecting different kinds of proteins or molecules, while comprehensive analysis of the sensing mechanism and dominant device factors of MoS2-FETs in response to proteins is yet to investigate. In this study, we first fabricated MoS2-FET biosensor and detected different types of proteins (immunoglobulin G (IgG), β-actin, and prostate-specific antigen (PSA)). Secondly, we built the model of the device and analyzed the sensing mechanism of MoS2-FETs in response to proteins. Experimental and modeling results showed that the induced doping effect and gating effect caused by the target protein binding to the device surface were the major influential factors. Specifically, the channel doping concentration and gate voltage (V
g) offset exhibited monotonic change as the concentration of the protein solution increases. For example, the channel doping concentration increased up to ∼37.9% and the V
g offset was ∼−1.3 V with 10−7
μg μl−1 IgG. The change was less affected by the device size. We also investigated the effects of proteins with opposite acid–base properties (β-actin and PSA) to IgG on the device sensing mechanism. β-actin and PSA exhibited behavior opposite to that of IgG. Additionally, we studied the response behavior of MoS2-FETs with different dimensions and dielectric materials (channel length, MoS2 thickness, dielectric layer thickness, dielectric layer material) to proteins. The underlying mechanisms were discussed in details. This study provides valuable guidelines for the design and application of MoS2-FET biosensors.
Unveiling the efficient state of Pd catalyst for robust electrocatalytic hydrodechlorination
Authors: Xu Shuyuan , Mei Bingbao , Li Fengjiao , Mao Jianing , Huang Changxing , Yan Yufeng , Chen Ningning , Xu Yinghua , Shi Meiqin
Published: July 2023

The application of electrochemical hydrodechlorination has been impeded due to the low utilization and activity of Pd catalyst. Herein, a series of Pd catalysts were prepared via the controllable evolution of Zn state during the pyrolysis of ZIF-8 nanosheet. Various forms of Pd with different chemical surroundings were generated upon the combined use of galvanic displacement and ion exchange process. Electrocatalytic hydrodechlorination of 4-chlorophenol was performed and the electrocatalytic hydrodechlorination efficiency of Pd/CN reaches 100% within 3 h at extra low Pd concentration. The coexistence of zero-valent Pd (Pd0) and nitrogen coordinated Pd (Pd–N) was verified by XAFS which provide multiple active sites for focusing on adsorbing H* and cracking C–Cl respectively. The synergetic effect between different chemical state of Pd for efficient hydrodechlorination of chloroaromatics and scheme for dexterous preparation of Pd based electrocatalyst are proposed and discussed.
Comprehensive evaluations of a prototype full field-of-view photon counting CT system through phantom studies
Authors: Zhan Xiaohui , Zhang Ruoqiao , Niu Xiaofeng , Hein Ilmar , Budden Brent , Wu Shuoxing , Markov Nicolay , Clarke Cameron , Qiang Yi , Taguchi Hiroki , Nomura Keiichi , Muramatsu Yoshihisa , Yu Zhou , Kobayashi Tatsushi , Thompson Richard , Miyazaki Hiroaki , Nakai Hiroaki
Published: July 2023

Objective. Photon counting CT (PCCT) has been a research focus in the last two decades. Recent studies and advancements have demonstrated that systems using semiconductor-based photon counting detectors (PCDs) have the potential to provide better contrast, noise and spatial resolution performance compared to conventional scintillator-based systems. With multi-energy threshold detection, PCD can simultaneously provide the photon energy measurement and enable material decomposition for spectral imaging. In this work, we report a performance evaluation of our first CdZnTe-based prototype full-size PCCT system through various phantom imaging studies. Approach. This prototype system supports a 500 mm scan field-of-view and 10 mm z-coverage at isocenter. Phantom scans were acquired using 120 kVp from 50 to 400 mAs to assess the imaging performance on: CT number accuracy, uniformity, noise, spatial resolution, material differentiation and quantification. Main results. Both qualitative and quantitative evaluations show that PCCT, under the tested conditions, has superior imaging performance with lower noise and improved spatial resolution compared to conventional energy integrating detector (EID)-CT. Using projection domain material decomposition approach with multiple energy bin measurements, PCCT virtual monoenergetic images have lower noise, and good accuracy in quantifying iodine and calcium concentrations. These results lead to increased contrast-to-noise ratio (CNR) for both high and low contrast study objects compared to EID-CT at matched dose and spatial resolution. PCCT can also generate super-high resolution images using much smaller detector pixel size than EID-CT and greatly improve image spatial resolution. Significance. Improved spatial resolution and quantification accuracy with reduced image noise of the PCCT images can potentially lead to better diagnosis at reduced radiation dose compared to conventional EID-CT. Increased CNR achieved by PCCT suggests potential reduction in iodine contrast media load, resulting in better patient safety and reduced cost.
Multiple transparency windows in an atom-assisted Laguerre–Gaussian rovibrational cavity
Authors: Badshah Fazal , Luqman Murtza Muhammad , Asghar Sobia , Ziauddin
Published: July 2023

An atom-assisted Laguerre–Gaussian rovibrational cavity is proposed to demonstrate the characteristics of the output probe field. The cavity comprises a fixed and moving mirror with a two-level qubit inside it, and the moving mirror can vibrate and rotate simultaneously. The addition of the qubit affects the output probe field properties, and the study explores the impact of various parameters on transparency windows. The article reports a new discovery of triple-transparency windows in a single-cavity system. The study also investigates the slow and fast light propagation in the output probe field and discusses the Stokes and anti-Stokes powers in the proposed cavity system. The findings have implications for the development of future optical devices and quantum communication systems.
Nonlinear interactions of two-kink-breather solution in Yu-Toda-Sasa-Fukuyama equation by modulated phase shift
Authors: Chen Mi , Wang Zhen
Published: July 2023

The waveforms and nonlinear interactions of a two-kink-breather solution of the (2 + 1)-dimensional Yu-Toda-Sasa-Fukuyama (YTSF) equation are studied by modulated phase shift. First, we obtain the parameter relations that respective affect the amplitudes of the kink and the breather solutions in kink-breather solution. Then, it is proved that the solutions in the regions near the singular boundaries of the phase shift can be divided into three kinds of solutions with repulsive or attractive interactions, in addition to the two-kink-breather solution. Interestingly, a breather soliton acts as a messenger to transfer energy during the repulsive interaction between the two kink-breather solutions with small amplitudes.
Sunlight harvesting in thin-film silicon solar cells using latticed Al2O3 anti-reflection coating, Ag disk NPs, and Ag back-reflector
Authors: Abdi Ghazal , Bahador Hamid
Published: July 2023

Solar energy is one of the renewable energy sources that has been made available to humans at no cost. Therefore, solar cells are a suitable alternative candidate for fossil fuels. Thin-film solar cells, despite being a cost-effective technology, have low efficiency. Therefore, in this research work, we provided a new architecture for a 200 nm Si solar cell, in which a latticed Al2O3 ARC is used as an antireflection, and Ag disk shape nanoparticles are placed on the front surface of the active layer in the center of the lattices. Furthermore, an Ag film is used as a back-reflector in the rear surface of the cell. By this design, because of the forward light scattering and near-field enhancement plasmonic effect of the Ag disk, reducing the Fresnel reflection from the cell surface by latticed ARC, and recycling the unabsorbed transmitted photons by BRS, the short-circuit current density and the efficiency can be reached to 14.67 mA cm−2, and 7.11%, respectively. These parameters equal 3.94 mA cm−2, and 1.78% for the bare cell, respectively.
Effects of f(R, G) gravity on anisotropic charged compact objects
Authors: Ilyas M , Athar A R , Khan F , Anfal Asma
Published: July 2023

The present study provides an in-depth analysis of the anisotropic matter distribution and various physical aspects of compact stars in the context of a f(R, G)-gravity framework. In order to gain an exhaustive understanding of these aspects, our study focuses on three particular compact stars: VELA X-1 (CS1), SAXJ1808.4-3658 (CS2), and 4U1820-30 (CS3). We conducted calculations on the relevant characteristics of these compact stars by employing three different models of f(R, G)-gravity. As a convenient approach, the f(R, G)-gravity is organized into two distinct components, which include f
1(R) and f
2(G). The R dependent component is modeled similarly to the Hu-Sawicki approach, while for modeling the G dependent component, we chose logarithmic and power law-like approaches and suggested three viable gravity models. Graphical methods are used to analyze the physical properties of the compact stars in the domain of suggested models of gravity.
Directional sensitivity of the NEWSdm experiment to cosmic ray boosted dark matter
Authors: Agafonova N.Y. , Alexandrov A. , Anokhina A.M. , Asada T. , Ashikhmin V.V. , Boccia V. , Centanni D. , Chernyavskii M.M. , Chin N. , D'Ambrosio N. , De Lellis G. , Di Crescenzo A. , Dowdy Y.C. , Dmitrievski S. , Enikeev R.I. , Galati G. , Galkin V.I. , Golovatiuk A. , Gorbunov S.A. , Gornushkin Y. , Guler A.M. , Gulyaeva V.V. , Iuliano A. , Khalikov E.V. , Kim S.H. , Konovalova N.S. , Krasilnikova Y.O. , Lauria A. , Lee K.Y. , Loschiavo V.P. , Managadze A.K. , Miloi A. , Montesi M.C. , Naka T. , Okateva N.M. , Park B.D. , Podgrudkov D.A. , Polukhina N.G. , Roganova T.M. , Rosa G. , Samoilov M.A. , Sadykov Z.T. , Sadovsky A. , Saeki K. , Sato O. , Shakiryanova I.R. , Shchedrina T.V. , Shiraishi T. , Sohn J.Y. , Sotnikov A. , Starkov N.I. , Starkova E.N. , Strekalina D.M. , Tioukov V. , Ursov E.D. , Ustyuzhanin A. , Vasina S. , Voronkov R.A. , Yoon C.S.
Published: July 2023

We present a study of a directional search for Dark Matter boosted forward when scattered by cosmic-ray nuclei, using a module of the NEWSdm experiment. The boosted Dark Matter flux at the edge of the Earth's atmosphere is expected to be pointing to the Galactic Center, with a flux 15 to 20 times larger than in the transverse direction.

The module of the NEWSdm experiment consists of a 10 kg stack of Nano Imaging Trackers, i.e. newly developed nuclear emulsions with AgBr crystal sizes down to a few tens of nanometers. The module is installed on an equatorial telescope. The relatively long recoil tracks induced by boosted Dark Matter, combined with the nanometric granularity of the emulsion, result in an extremely low background. This makes an installation at the INFN Gran Sasso laboratory, both on the surface and underground, viable. A comparison between the two locations is made. The angular distribution of nuclear recoils induced by boosted Dark Matter in the emulsion films at the surface laboratory is expected to show an excess with a factor of 3.5 in the direction of the Galactic Center. This excess allows for a Dark Matter search with directional sensitivity. The surface laboratory configuration prevents the deterioration of the signal in the rock overburden and it emerges as the most powerful approach for a directional observation of boosted Dark Matter with high sensitivity. We show that, with this approach, a 10 kg module of the NEWSdm experiment exposed for one year at the Gran Sasso surface laboratory can probe Dark Matter masses between 1 keV/c2and 1 GeV/c2and cross-section values down to 10-30cm2with a directional sensitive search.
Penetration properties of applied resonant magnetic perturbation in HL-2A tokamak
Authors: Wang X. , Zhang H.W. , Chen W.J. , Sun T.F. , Zhang W. , Ma Z.W.
Published: July 2023

Any arbitrary perturbation on a magnetic field separatrix can cause a structure named homoclinic tangle in tokamaks. Both an edge localized mode (ELM) and a resonant magnetic perturbation (RMP) can lead to a perturbation of the magnetic field on the separatrix. Under the appropriate circumstances, RMP could alleviate or even completely suppress a rapid collapse process of an ELM. The simulation results using the CLTx code, the extended version of the three-dimensional toroidal magnetohydrodynamic (MHD) code (CLT (Ci-Liu-Ti, which means MHDs in Chinese)) with a scrape-off layer, show the structure of the homoclinic tangle with a borderline stochastic region resulting from RMP in HL-2A tokamak. Strongly distorted magnetic field lines with the homoclinic tangle could connect to the tokamak divertors. The footprints of these magnetic field lines on the divertors are consistent with the energy deposit spots in the experiment. From Poincaré plots of escaped magnetic field lines, it is found that the depth of the plasma edge region penetrated by these field lines depends on the RMP coil current, the rotation frequency of the RMP field, and the plasma resistivity.
Detection Method of Protruding Defects of Parts Based on Improved Threshold Segmentation
Authors: Zi-jun Liu , Rong-rong Wang , Dong Wei
Published: July 2023

Aiming at a series of problems that the traditional threshold segmentation method has low detection accuracy in detecting part bulge defects, a part bulge defect detection method based on improved threshold segmentation is proposed in this paper. Firstly, the parts to be tested are obtained, and then the image is filtered and denoised. Because the traditional median filter has some limitations, a fast weighted median filtering algorithm is proposed. Then the image is enhanced, and the method based on Laplace operator is used to enhance the image. Then Otsu threshold segmentation and iterative threshold segmentation are used respectively. It is found that there are still many non convex defects, which have a great impact on the detection accuracy. Therefore, an improved iterative threshold segmentation is proposed. The difference operation is carried out between the standard part and the part to be tested, and the above three methods are compared. The results indicate that the better iterative threshold segmentation method can effectively test the convex fault of the compent.
Remainder particles detection of closed electronic equipment equipped in spacecraft based on a coarse- to- fine framework
Authors: Hua Shiyan , Li Dawei
Published: July 2023

Remainder particles in closed electronic equipment equipped in spacecraft are a potential threat to spacecraft. The volume of remainder particles is tiny, and remainder particles are similar to the general components of equipment in shape and size. So the current methods used to detect remainder particles cause false detection and missing detection seriously. In order to resolve above problems, a coarse- to- fine framework is proposed to detect remainder particles in closed electronic equipment of spacecraft, which includes a backbone network, a coarse classifier, and a fine detector. At first, we use ResNet-18 as the backbone network to learn the robust feature of remainder particles. Then, we design a coarse classifier. The feature maps containing remainder particles are filtered from it. Finally, the extracted patches containing remainder particles are sent to the fine detector for further location of remainder particles. The experimental results indicate that our framework exhibits superior performance on various evaluation indicators, especially reaching 92.54% on AP. It realizes efficient and accurate detection of remainder particles in closed electronic equipment of spacecraft.
Research on the strong transient process of the secondary air system in the Aero-engine based on the network method
Authors: Liu Haiming
Published: July 2023

A coupled model of engine mainstream way with secondary air system was established based on the network method. The change rule of engine performance, air system parameters and axial force was simulated when the aero-engine was sunk in shaft failure. The dynamic parameters of the secondary air system could be forecast accurately based on the analysis of transient algorithm, and the transient axial force also could be calculated. So the simulation data can be provided for the engineering design, and it can help the designer improve the secondary air system design. Moreover, its modular character allows integration of further detailed air-system unites and establishment of more complex air system network. The resultant modular tool is prospect in studying the complex dynamic characteristics and mechanism in Aero-engine air system.