bluuebunny/crossref_metadata_2025 huggingface dataset:
Examining the calcium sensitivity of skeletal muscle thick filaments
Authors: Short Ben
Published: November 2023

JGP study (this issue, Caremani et al. https://doi.org/10.1085/jgp.202313393) reveals that the calcium sensitivity of thick filament structure in skeletal muscle is greater than that of force, offering new insights into the mechanisms of thick filament activation.
Key comparisons of air kerma and absorbed dose to water standards in 60Co radiation beam (EURAMET.RI(I)-K1.3 and EURAMET.RI(I)-K4.3)
Authors: Nylund R , Prez L A de , Hetland P O , Andersen C E , Aviles P , Mulas C G , Msimang Z , Czap L , Persson L
Published: November 2023

Main text

A key comparison of the standards for air kerma and absorbed dose to water of seven participating laboratories was carried out in the 60Co radiation beam, therapy level, during October 2021 to November 2022. Six of the participating laboratories are secondary standards laboratories (SSM, DSA, STUK, DTU, CIEMAT, and IAEA) and VSL is a primary standards laboratory and acted as a linking laboratory to respective BIPM key comparisons. The comparison results are published in the BIPM key comparison database (KCDB) under the reference EURAMET.RI(I)-K1.3 and EURAMET.RI(I)-K4.3. The comparison was made indirectly using three thimble-type ionization chambers as transfer instruments. The results are analyzed and presented in terms of degrees of equivalence suitable for entry in the BIPM key comparison database.

To reach the main text of this paper, click on Final Report. Note that this text is that which appears in Appendix B of the BIPM key comparison database https://www.bipm.org/kcdb/.

The final report has been peer-reviewed and approved for publication by the CCRI, according to the provisions of the CIPM Mutual Recognition Arrangement (CIPM MRA).
Data-driven discovery of ultraincompressible crystals from a universal correlation between bulk modulus and volumetric cohesive energy
Authors: Yuan Xiaoang , Gao Enlai
Published: November 2023

Bulk modulus and cohesive energy are two important quantities of condensed matter. From the interatomic energy landscape, we here derived a correlation between the bulk modulus (B) and the volumetric cohesive energy (ρ
e), i.e. B = 2(ln2)2
ρ
e/9ϵ
s
2 = kρ
e, where ϵ
s and k are the strain-to-failure of interatomic bonds and the factor of proportionality, respectively. By analyzing numerous crystals from first principles calculations, it was shown that this correlation is universally applicable to various crystals including simple substances and compounds. Most interestingly, it was found that ϵ
s of crystals with a similar structure are almost a constant, resulting in a linear relationship between B and ρ
e. Furthermore, we found that the value of k for any compound can be determined based on the rule of mixtures, i.e. k= ∑x
i
k
i, where x
i and k
i are the atomic fraction and the factor of proportionality for each element in this compound, respectively. Finally, this correlation was used to predict the bulk moduli for a vast number of crystals with known ρ
e in databases. After first principles verification of the top 50 crystals with the highest predicted bulk modulus, 25 ultraincompressible crystals with a bulk modulus greater than 400 GPa that can rival diamond (436 GPa) were discovered.
A fusion non-convex group sparsity difference method and its application in rolling bearing fault diagnosis
Authors: Wei Huiyong , Cai Gaigai , Liu Zeyu , Wang Shibin
Published: November 2023

Bearing fault is a common factor leading to machine failures. How to extract the periodic transient signal due to bearing faults submerged in strong noise is a challenging problem for bearing fault diagnosis. Total variation denoising is a method used to remove noise and extract features. However, it solely relies on the sparsity of the first-order difference of the signal, resulting in the loss of important features and underestimation of amplitude. Additionally, it fails to capture the periodicity of the signal. To address these issues, a novel approach called fusion non-convex group sparsity difference (FNC-GSD) method is proposed for bearing fault diagnosis. Firstly, it is recognized that noise does not exhibit sparsity in the difference domain, while transient signal exhibits group sparsity in the difference domain. This grouping property enhances the feature selection ability of sparse model. Inspired by this, the group sparsity of the transient signal in the difference domain is used to preserve the fault features as much as possible. Additionally, in order to promote sparsity of the signal itself in the time domain to preserve the potential impulse component, a l
1-norm regularization term is introduced. Furthermore, a non-convex sparsity-inducing penalty function strategy is employed to prevent amplitude underestimation. The proposed sparse model considers both the group sparsity in the difference domain and the sparsity in the time domain of the transient signal, and its solution is derived according to the majorization–minimization algorithm. And the particle swarm optimization algorithm is used to adaptively search the regularization parameters of FNC-GSD. Finally, multiple bearing fault diagnosis experiments are conducted to demonstrate the performance of the FNC-GSD. The results show that it has advantages in fault feature extraction compared with some other methods.
An interactive nuclei segmentation framework with Voronoi diagrams and weighted convex difference for cervical cancer pathology images
Authors: Yang Lin , Lei Yuanyuan , Huang Zhenxing , Geng Mengxiao , Liu Zhou , Wang Baijie , Luo Dehong , Huang Wenting , Liang Dong , Pang Zhifeng , Hu Zhanli
Published: November 2023

Objective. Nuclei segmentation is crucial for pathologists to accurately classify and grade cancer. However, this process faces significant challenges, such as the complex background structures in pathological images, the high-density distribution of nuclei, and cell adhesion. Approach. In this paper, we present an interactive nuclei segmentation framework that increases the precision of nuclei segmentation. Our framework incorporates expert monitoring to gather as much prior information as possible and accurately segment complex nucleus images through limited pathologist interaction, where only a small portion of the nucleus locations in each image are labeled. The initial contour is determined by the Voronoi diagram generated from the labeled points, which is then input into an optimized weighted convex difference model to regularize partition boundaries in an image. Specifically, we provide theoretical proof of the mathematical model, stating that the objective function monotonically decreases. Furthermore, we explore a postprocessing stage that incorporates histograms, which are simple and easy to handle and prevent arbitrariness and subjectivity in individual choices. Main results. To evaluate our approach, we conduct experiments on both a cervical cancer dataset and a nasopharyngeal cancer dataset. The experimental results demonstrate that our approach achieves competitive performance compared to other methods. Significance. The Voronoi diagram in the paper serves as prior information for the active contour, providing positional information for individual cells. Moreover, the active contour model achieves precise segmentation results while offering mathematical interpretability.
A comparative analysis of parallel SSHI and SEH for bistable vibration energy harvesters
Authors: Demouron Quentin , Morel Adrien , Gibus David , Benhemou Aya , Badel Adrien
Published: November 2023

The present work focuses on ambient vibration energy harvesting. Specifically, this article deals with bistable piezoelectric energy harvesters (PEHs) which exhibits a wider bandwidth than linear oscillators. These complex systems require an energy extraction circuit (EEC) to rectify their voltage to supply power to autonomous sensors. This EEC needs to be optimized in order to increase the harvested power and even the bandwidth of PEHs. Because of the complex dynamics of bistable PEHs, there is a lack of simple and physically-insightful models in the literature that would allow the understanding and optimization of the extraction circuit. To address this issue, the present work derives closed-form models of a bistable PEH coupled to a passive and an active synchronous EEC: respectively the standard energy harvesting (SEH) circuit and the parallel synchronized switch harvesting on inductor (P-SSHI) circuit. Experimental measurements conducted on a custom bistable PEH demonstrate the validity of the proposed models with a relative error lower than 15% on the harvested power and the bandwidth. The proposed models allow to easily understand the influence of the P-SSHI circuit on the dynamics of a bistable PEH. Moreover, a comparison of the performance of the SEH and the P-SSHI circuits, valid for any bistable generator, is proposed. The latter shows that under low electromechanical coupling and low acceleration amplitude the P-SSHI circuit leads to multiply the maximum harvested power up to 4.3 compared to the SEH circuit, and the bandwidth by a factor of 2.3.
Constructing artificial boundary condition of dispersive wave systems by deep learning neural network
Authors: Zheng Zijun , Shao Jiaru , Zhang Ziying
Published: November 2023

To solve one dimensional dispersive wave systems in an unbounded domain, a uniform way to establish localized artificial boundary conditions is proposed. The idea is replacing the half-infinite interval outside the region of interest with a super element which exhibits the same dynamics response. Instead of designing the detailed mechanical structures of the super element, we directly reconstruct its stiffness, mass, and damping matrices by matching its frequency-domain reaction force with the expected one. An artificial neural network architecture is thus specifically tailored for this purpose. It comprises a deep learning part to predict the response of generalized degrees of freedom under different excitation frequencies, along with a simple linear part for computing the external force vectors. The trainable weight matrices of the linear layers correspond to the stiffness, mass, and damping matrices we need for the artificial boundary condition. The training data consists of input frequencies and the corresponding expected frequency domain external force vectors, which can be readily obtained through theoretical means. In order to achieve a good result, the neural network is initialized based on an optimized spring-damper-mass system. The adaptive moment estimation algorithm is then employed to train the parameters of the network. Different kinds of equations are solved as numerical examples. The results show that deep learning neural networks can find some unexpected optimal stiffness/damper/mass matrices of the super element. By just introducing a few additional degrees of freedom to the original truncated system, the localized artificial boundary condition works surprisingly well.
Hybrid multilevel-multiwavelength signaling scheme for optical data transmission
Authors: Maximov Mikhail V , Shernyakov Yuri M , Gordeev Nikita Yu , Dubrovskii Vladimir G , Nadtochiy Alexey M , Zhukov Alexey E
Published: November 2023

We suggest an idea of data encoding scheme based on the switching from the ground state (GS) to excited state (ES) lasing in quantum dot (QD) lasers with increase in injection current. The groups of two bits are assigned to lasing spectra that comprise either one or both GS and/or ES lasing lines depending on injection current. We expect that the proposed encoding scheme can potentially combine some advantages of multilevel signaling and wavelength division multiplexing.
Size effects in molecular dynamic simulations of fracture in bcc iron crystals
Authors: Pařík Petr , Machová Anna , Červ Jan , Uhnáková Alena , Hora Petr
Published: November 2023

Three-dimensional (3D) simulations via molecular dynamics (MD) show that the brittle or ductile behavior of the atomistic samples with the edge crack (001)[110] (crack plane/crack front) depend on size of the self-similar atomistic crystals. Since the basic continuum predictions concerning cracks do not consider the random thermal atomic motion, we are restricted in this study to MD simulations with initial temperature of 0 K. For all samples tested, the crack initiation is brittle. However, the subsequent crack growth can be inhibited by twin formation on oblique planes {112}, crack branching along {011} planes and new dislocation emissions on {123} slip planes and the final fracture can also be then ductile, which depends predominantly on the thickness of the atomistic sample. The representative quantity, the atomistic fracture toughness initially increases with increasing sample thickness and later saturates near Griffith level for plane strain state along the crack front. The tested loading rates are equivalent to a cross head speed of 0.833 · 10−4 m s−1 used in one our previous experiment. These new MD results comply with the stress analysis performed by the anisotropic linear fracture mechanics (LFM) and with some experimental observations.
Investigation of Ag/ZnO/p-Si heterostructure for diode and photodiode applications in visible spectrum
Authors: Yıldız Dilber Esra , Kocyigit Adem , Yıldırım Murat
Published: November 2023

Photodiodes have gained great attention for lightning control and optical communication over the last two decades. To obtain faster and more sensitive photodiodes are important for industrial applications. In this study, atomic layer deposition (ALD) technique was used to fabricate ZnO interlayer on p-Si, and thermal evaporation technique was employed to deposit Ag rectifying and Al ohmic contacts on ZnO and back surface of p-Si, respectively. The UV–Vis spectrometer was used to characterize optical behaviors of the ZnO interlayer. I-V measurements were conducted to characterize of Ag/ZnO/p-Si heterostructure for various solar light power intensities of dark, 20, 40, 60, 80 and 100 mW cm−2 and at various wavelengths from 351 nm to 800 nm by 50 nm intervals. According to I-V characteristics, the device exhibited increasing current at reverse biases depending on increasing light power intensity, and this confirmed photodiode behavior. Various diode parameters such as rectifying ratio, threshold voltage, series resistance, barrier height, etc. were determined and discussed in details from forward bias characteristics to investigate diode characteristics of the Ag/ZnO/p-Si heterostructure. The photodetection parameters such as responsivity, specific detectivity and external quantum efficiency (EQE) also were investigated. The Ag/ZnO/p-Si heterostructure exhibits good photodetection performance at all visible range of electromagnetic spectrum and can be good candidate for optoelectronic applications.
Electrochemical analysis of thermally treated two dimensional zinc sulphide hexagonal nano-sheets with reduced band gap
Authors: Phogat Peeyush , Shreya  , Jha Ranjana , Singh Sukhvir
Published: November 2023

Significantly reduced band gap (2.0 eV) zinc sulphide (ZnS) nanoparticles are synthesized using microwave/ultraviolet/ultrasonic assisted hydrothermal route in a two step process. Initially, ZnS nanospheres are synthesized, showing a cubic structural phase with a band gap of 3.2 eV, which is further annealed at 1000 °C to get the final product. Following annealing, the cubic ZnS undergoes a phase change to wurtzite ZnS, in the form of hexagonal nanosheets showing polymorphism phenomena, along with a reduced band gap of 2 eV. The optical analysis reveals a red shift in the absorbance region, transitioning from the absorption of UV radiations in cubic ZnS to visible radiations in wurtzite ZnS. Thermogravimetric (TGA) measurements and its analysis also revealed the phase change of ZnS (cubic) to ZnS (Wurtzite) when heated at 1000 °C. Microstructural analysis reveals the formation of sheets oriented along (100) plane, which is evidenced by the interplanar spacing and lattice fringes. The photoluminscence spectra highlights quantum energy states present between the highest occupied molecular orbital (HOMO), which is 2.36 eV for cubic phase and 1.76 eV for the hexagonal phase, and the lowest unoccupied molecular orbital (LUMO), with values of −0.84 eV for cubic while −0.24 for hexagonal ZnS. The CIE coordinates for wurtzite ZnS, at X= 0.55 and Y= 0.23, corresponds to red light emission. The suitability of wurtzite phase ZnS for solar cell applications has been demonstrated through electrochemical studies using Nyquist plot and cyclic voltrammetry (CV) techniques. CV demonstrates the presence of redox peaks and reversibility of the material during the redox process. The diffusive behaviour is also confirmed by observing the variation of peak current with scan rate, following Rendle Sevick equation. The presence of Warburg diffusion in Nyquist plot indicates the efficient charge transfer dynamics of the material, suggesting a high potential for exciton formation in energy production. Consequently, this material stands as a promising candidate for efficient solar cells.
Development of a quasi-ring airy vortex beam using an all-dielectric geometric phase metasurface
Authors: Cheng Kaixiang , Hu Zheng Da , Wu Jingjing , Wang Jicheng , Khakhomov Sergei
Published: November 2023

The quasi-ring Airy vortex beam (QRAVB) is a special type of vortex beam was recently proposed, which performs efficiently in turbulent environments. However, bulky optical elements, such as the spatial light modulator, used for generating the QRAVB hinder its application in modern integrated optical communication devices. Here, we present a type of compact optical element developed for generating the QRAVB by using an all-dielectric geometric phase metasurface. We simulate the performance of the designed metasurface and discuss several properties, such as autofocusing and self-healing of the metasurface-generated beams, are similar to Airy beams. This type of metasurface has potential applications in integrated free-space optical communication and on-chip optical information processing in the future.
Role of morphology and composition in the transport properties of highly conducting CVD grown PtTex
Authors: Nidhi  , Singh Hardeep , Das Samaresh , Nautiyal Tashi
Published: November 2023

Platinum telluride (PtTex), a metallic noble transition-metal dichalcogenide, has emerged as a central candidate for magnetic and optoelectronic applications. Recently, PtTex has drawn great attention because of its large positive magnetoresistance and broadband photodetection owing to its astounding electron transport properties. Here, we report the role of morphology, texture, and composition in the transport properties of CVD-grown highly conducting PtTex. Two different compositions of Te atoms, named tellurium stoichiometric (TS) and tellurium rich (TR), with different morphology have been obtained in the PtTex films. The highest longitudinal conductivity was found to be ∼ 3.57 × 107 and 3.83 × 106 S m−1 at 200 K in the TR and TS-PtTex samples, respectively. The maximum carrier density in TR and TS-PtTex samples was found to be of the order of 1022 and 1021 cm−3, respectively. Further, the negative magnetoresistance has also been found to be ∼ −2.2% at 300 K in the presence of an in-plane magnetic field of 9 T. Our results, reporting extremely high conductivity along with negative magnetoresistance, promise exciting applications of PtTex for nanoelectronic devices.
The Atacama Cosmology Telescope: map-based noise simulations for DR6
Authors: Atkins Zachary , Duivenvoorden Adriaan J. , Coulton William R. , Qu Frank J. , Aiola Simone , Calabrese Erminia , Chesmore Grace E. , Choi Steve K. , Devlin Mark J. , Dunkley Jo , Hervías-Caimapo Carlos , Guan Yilun , Posta Adrien La , Li Zack , Louis Thibaut , Madhavacheril Mathew S. , Moodley Kavilan , Naess Sigurd , Nati Federico , Niemack Michael D. , Page Lyman , Puddu Roberto , Salatino Maria , Sifón Cristóbal , Staggs Suzanne T. , Vargas Cristian , Vavagiakis Eve M. , Wollack Edward J.
Published: November 2023

The increasing statistical power of cosmic microwave background (CMB) datasets requires a commensurate effort in understanding their noise properties. The noise in maps from ground-based instruments is dominated by large-scale correlations, which poses a modeling challenge. This paper develops novel models of the complex noise covariance structure in the Atacama Cosmology Telescope Data Release 6 (ACT DR6) maps. We first enumerate the noise properties that arise from the combination of the atmosphere and the ACT scan strategy. We then prescribe a class of Gaussian, map-based noise models, including a new wavelet-based approach that uses directional wavelet kernels for modeling correlated instrumental noise. The models are empirical, whose only inputs are a small number of independent realizations of the same region of sky. We evaluate the performance of these models against the ACT DR6 data by drawing ensembles of noise realizations. Applying these simulations to the ACT DR6 power spectrum pipeline reveals a ∼ 20% excess in the covariance matrix diagonal when compared to an analytic expression that assumes noise properties are uniquely described by their power spectrum. Along with our public code, mnms, this work establishes a necessary element in the science pipelines of both ACT DR6 and future ground-based CMB experiments such as the Simons Observatory (SO).
Comparative study on phase transition behaviors of fractional molecular field theory and random-site Ising model
Authors: Liu 刘 Ting-Yu 婷玉 , Zhao 赵 Wei 薇 , Wang 王 Tao 涛 , An 安 Xiao-Dong 小冬 , Wei 卫 Lai 来 , Huang 黄 Yi-Neng 以能
Published: November 2023

Fractional molecular field theory (FMFT) is a phenomenological theory that describes phase transitions in crystals with randomly distributed components, such as the relaxor-ferroelectrics and spin glasses. In order to verify the feasibility of this theory, this paper fits it to the Monte Carlo simulations of specific heat and susceptibility versus temperature of two-dimensional (2D) random-site Ising model (2D-RSIM). The results indicate that the FMFT deviates from the 2D-RSIM significantly. The main reason for the deviation is that the 2D-RSIM is a typical system of component random distribution, where the real order parameter is spatially heterogeneous and has no symmetry of space translation, but the basic assumption of FMFT means that the parameter is spatially uniform and has symmetry of space translation.
Core-level spectroscopy of the photodissociation process of BrCN molecule
Authors: Zhou 周 Kun 坤 , Wang 王 Han 涵
Published: November 2023

Fewest-switches surfacing hopping (FSSH) simulations have been performed with the high-level multi-reference electronic structure method to explore the coupled electronic and nuclear dynamics upon photoexcitation of cyanogen bromide (BrCN). The potential energy surfaces (PES) of BrCN are charted as functions of the Jacobi coordinates (R, θ). An in-depth examination of the FSSH trajectories reveals the temporal dynamics of the molecule and the population changes of the lowest twelve states during BrCN’s photodissociation process, which presents a rich tapestry of dynamical information. Furthermore, the carbon K-edge x-ray absorption spectroscopy (XAS) is calculated with multi-reference inner-shell spectral simulations. The rotation of the CN fragment and the elongation of the C–Br bond are found to be the reason for the peak shifting in the XAS. Our findings offer a nuanced interpretation for inner-shell probe investigations of BrCN, setting the stage for a deeper understanding of the photodissociation process of cyanogen halides molecules.
Dilation, discrimination and Uhlmann’s theorem of link products of quantum channels
Authors: Lei 雷 Qiang 强 , Cao 操 Liuheng 刘桁 , Kumar Asutosh , Wu 武 Junde 俊德
Published: November 2023

We establish the Stinespring dilation theorem of the link product of quantum channels in two different ways, discuss the discrimination of quantum channels, and show that the distinguishability can be improved by self-linking each quantum channel n times as n grows. We also find that the maximum value of Uhlmann’s theorem can be achieved for diagonal channels.
Spin splitting of vortex beams on the surface of natural biaxial hyperbolic materials
Authors: Liang 梁 Hong 红 , Song 宋 Haoyuan 浩元 , Li 李 Yubo 宇博 , Yu 于 Di 迪 , Fu 付 Shufang 淑芳
Published: November 2023

We investigated the spin splitting of vortex beam on the surface of biaxial natural hyperbolic materials (NHMs) rotated by an angle with respect to the incident plane. An obvious asymmetry of spatial shifts produced by the left-handed circularly (LCP) component and right-handed circularly polarized (RCP) component is exhibited. We derived the analytical expression for in- and out-of-plane spatial shifts for each spin component of the vortex beam. The orientation angle of the optical axis plays a key role in the spin splitting between the two spin components, which can be reflected in the simple expressions for spatial shifts without the rotation angle. Based on an α-MoO3 biaxial NHM, the spatial shifts of the two spin components with the topological charge were investigated. As the topological charge increases, the spatial shifts also increase; in addition, a tiny spatial shift close to zero can be obtained if we control the incident frequency or the polarization of the reflected beams. It can also be concluded that the maximum of the spin splitting results from the LCP component at p-incidence and the RCP component at s-incidence in the RB-II hyperbolic frequency band. The effect of the incident angle and the thickness of the α-MoO3 film on spin splitting is also considered. These results can be used for manipulating infrared radiation and optical detection.
Control of laser-plasma instabilities by non-collinear polychromatic light
Authors: Zhao Yao , Yin Hongwei , Zhao Bin , Cui Zijian
Published: November 2023

Normal broadband lasers with collinear polychromatic components have immense potential for mitigating laser plasma instabilities (LPIs). However, the projection complexity of collinear polychromatic light (CPL) is a significant challenge owing to the demand for a large bandwidth and beamlet number. Here, we propose a theoretical LPI model and optical design for non-collinear polychromatic light (NCPL), which has a small angle

∼

4
∘

and large frequency difference ∼1% between the double-color beamlets. LPI models of the NCPL demonstrate a decoupling threshold for the shared daughter waves under a multibeam configuration. Compared with the CPL, the wavevector couplings of LPIs are further reduced by the introduced angle. Therefore, both the growth rate and saturation level of LPIs are greatly mitigated by using the NCPL. The two- and three-dimensional simulation results indicate that the NCPL reduces the absolute and convective decoupling thresholds of the CPL and is sufficient to effectively mitigate the reflectivity, hot-electron generation, and intensity of cross-beam energy transfer. An optical design for the efficient generation of ultraviolet NCPL has been presented based on the unsaturated optical parametric amplification and non-collinear sum-frequency generation.
Two-layer neural network on infinite-dimensional data: global optimization guarantee in the mean-field regime
*
Authors: Nishikawa Naoki , Suzuki Taiji , Nitanda Atsushi , Wu Denny
Published: November 2023

The analysis of neural network optimization in the mean-field regime is important as the setting allows for feature learning. The existing theory has been developed mainly for neural networks in finite dimensions, i.e. each neuron has a finite-dimensional parameter. However, the setting of infinite-dimensional input naturally arises in machine learning problems such as nonparametric functional data analysis and graph classification. In this paper, we develop a new mean-field analysis of a two-layer neural network in an infinite-dimensional parameter space. We first give a generalization error bound, which shows that the regularized empirical risk minimizer properly generalizes when the data size is sufficiently large, despite the neurons being infinite-dimensional. Next, we present two gradient-based optimization algorithms for infinite-dimensional mean-field networks, by extending the recently developed particle optimization framework to the infinite-dimensional setting. We show that the proposed algorithms converge to the (regularized) global optimal solution, and moreover, their rates of convergence are of polynomial order in the online setting and exponential order in the finite sample setting, respectively. To the best of our knowledge, this is the first quantitative global optimization guarantee of a neural network on infinite-dimensional input and in the presence of feature learning.
SAR Analysis Using Various Substrates of Microstrip Antenna for Breast Cancer Hyperthermia Treatment
Authors: Hassan Mazlina Mansor , Lias Kasumawati , Buniyamin Norlida , Narihan Mohamad Zulkarnaen Ahmad , Naimullah Bibi Sarpinah Sheikh , Ispawi Dzufi Iszura
Published: November 2023

Hyperthermia is an alternative technique used to treat breast cancer using high heat, around 41°C to 45°C, to denature cancer tissue into necrotic tissue. It can work independently or in adjuvant with other conventional methods. The design of an antenna with a suitable substrate is essential for the applicator to transmit maximal heat to the intended area and distribute the heat uniformly on the treated tissues. Therefore, the inset feed microstrip antenna is design with five different substrates, simulated, analyzed, and their performance is compared to get the best substrate. The substrates used include Rogers Duroid RT5880, Rogers RO4003, FR4, Alumina and Rogers RO3010. SEMCAD X 14.8.4 software is used to design, simulate and generate SAR. RT5880 and RO4003 show better SAR distribution and focus position distance (FPD), which can be further examined for future research. 2450 MHz, 915 MHz and 434 MHz frequencies are compared to find the most suitable frequency to apply with the applicator. A 915 MHz frequency shows better performance which can penetrate more toward the cancerous areas. However, there are several deficiencies such as difficulty in controlling FPD, wide unwanted hotspot and massive skin burn problem, that needs to be improved to provide less adverse health effects due to the execution of hyperthermia treatment. The selection of suitable substrates can help reduce the deficiencies and improve the effectiveness of the hyperthermia technique. The estimated period is within 2 hours to 3.6 hours to achieve sufficient heating to destroy the cancerous cells.
Impact of Cortical Bone Thickness on the Parameters of Fast and Slow Ultrasound Wave based on 2-D Simulation
Authors: Wahab Muhamad Amin Bin Abd , Sudirman Rubita , Mahmood Nasrul Humaimi
Published: November 2023

Quantitative Ultrasound (QUS) has been introduced to measure the quality of human bones using ultrasound and become one of the prevention methods for Osteoporosis diseases. Because of the porous composition inherent in human cancellous bone, the generation of both fast and slow waves occurs, and these waves exhibit a distinct association with the cancellous bone structure, particularly the extent of porosity. Nonetheless, the presence of these waves is also contingent upon the anisotropy of cancellous bone, and it is noteworthy that most human cancellous bones are enveloped by cortical bone, which may influence the parameters of the fast and slow waves. Therefore, the aim of this study is to perform a 2-Dimensional (2-D) simulation utilizing the through transmission (TT) measurement method. The primary focus is to examine the impact of cortical thickness on the parameters of both the fast and slow waves. The cortical thickness will be added to the cancellous bone models and the thickness will be varied. Then, the fast and slow wave parameters will be compared in terms of correlation coefficient to identify which wave is affected more. The result shows that the cortical thickness causes increasing in attenuation and velocity for both fast and slow waves. The increase in attenuation is due to sonometry effects while the different longitudinal velocities of water and bone material may contribute to the behaviors for phase velocity measurements. However, the fast wave shows more correlation with the cortical thickness for attenuation (R2
= 0.76) and phase velocity (R2
= 0.77) parameters. This is due to fast wave corresponding to the solid structure and increasing cortical thickness also increase the solid structure. Thus, analyzing fast waves against human cancellous bone, cortical bone thickness needs to be considered to ensure accurate measurements.
Field Oriented Control Implementation on BLDC Motor Controller with PI and SVPWM using STM32F103C8T6
Authors: Prayogo Rofiq Cahyo , Triwiyatno Aris , Riyadi Munawar Agus
Published: November 2023

Brushless direct current (BLDC) motor are high power density motors with a wide scope for use in electric vehicles, home automation, and industry. But the motor performance degrades due to improper control actions. This is caused by uncontrolled BLDC motor torque currents. Field Oriented Control (FOC) method is a solution for controlling BLDC motor, because it has the advantaged of overcoming torque ripples at low speeds. This paper presents the implementation of FOC on BLDC motor using STM32F103C8T6, which is high speed and low cost microcontroller. STM32F103C8T6 has been applied to handle FOC algorithm calculation and data processing. In order to validate the FOC algorithm system and assess the performance of the STM32F103C8T6 microcontroller, a 350-watt BLDC motor on an electric bicycle was tested and compared with a Universal controller. The tests that have been conducted proven that the FOC controller makes power more efficient, rotates BLDC motor at low speeds, and reduces torque ripple.
EPID-based in vivo dosimetry – new developments and applications
Authors: McCurdy B M C
Published: November 2023

In vivo dosimetry has been shown to be a powerful quality assurance method in modern radiation therapy. The most common tool used for in vivo dosimetry is the electronic portal imaging device (EPID) which can quantitatively image the therapeutic beam fluence exiting the patient during treatment delivery. Since the last major literature review on this topic was published five years ago, the radiation oncology community has shown continued strong interest in this subject. Commercial options have become more widely available, with a related increase in validation efforts and sensitivity testing, while new applications continue to be explored. Work has been done to understand and increase the accuracy of the EPID for dosimetric applications, as well as continued efforts to provide practical, quantitative experiences from clinical implementation of in vivo dosimetry systems. This review examines the published literature related to in vivo EPID dosimetry from January 2017 to February 2022. The literature is classified into three main topical areas: (1) new or improved algorithmic developments including validation work, (2) applications of the in vivo EPID dosimetry method, and (3) error identification and error sensitivity analyses.
Contemporary Applications of Cherenkov Imaging in Radiation Therapy
Authors: Zhang R , Decker S , Alexander D , Ashraf R , Rahman M , Hachadorian R , Gill G , Rose M , Hunt B , Hoopes P J , Jarvis L , Bruza P , Gladstone D , Pogue B
Published: November 2023

Cherenkov radiation (CR) is produced from all high energy radiation sources and is part of the dose delivery process in tissue. As such, CR is a direct indicator of the dose delivery process and in recent years the ability to image and measure CR has provided a number of ways to help with radiotherapy dosimetry and delivery tracking. This review provides an overview of the fundamental physical principles of CR production and the radiation transport in tissue, along with applications of imaging CR that have seen significant development in the past few years.
Characterisation and application of three-dimensional silicone-based radiochromic dosimetry in 1.5 T magnetic resonance imaging-guided radiotherapy
Authors: Jensen Morten B , Balling Peter , Riis Hans L , Bertelsen Anders S , Jensen Simon V , Doran Simon J , Petersen Jørgen B B , Muren Ludvig P
Published: November 2023

The magnetic field in magnetic resonance imaging-guided radiotherapy (MRgRT) systems influences the three-dimensional (3D) dose deposition and hence the delivered dose distributions. The aim of this study was to investigate the dose-rate dependency and dose response of silicone-based radiochromic dosimeters for photon irradiation in the precense of a magnetic field using a 1.5 T MRgRT system. Additionally, the study aimed to provide a proof of the concept of radiotherapy treatment based on a treatment plan calculated on magnetic resonance imaging rather than a computed tomography (CT) scan. The delivered dose was read out in 3D with an optical CT scanner and the dose distribution was verified using gamma analysis. We found an insignificant dose-rate dependency for dose rates ranging from 3.2 to 5.1 Gy/min and a linear dose response up to 20 Gy. A 3D 3%/3mm gamma analysis showed a pass rate of 95.1%. The dosimeter showed clinical potential for 3D dose verification of MRgRT delivery.
Investigation of the Dosimetry Characteristics of the GAFCHROMIC® EBT3 Film Response to Alpha Particle Irradiation
Authors: Cyr Mélodie , Martinez Victor D. , Devic Slobodan , Tomic Nada , Lewis David F. , Enger Shirin A.
Published: November 2023

The purpose of this study was to investigate the dosimetric characteristics of the GAFCHROMIC® EBT3 film responding to alpha particle irradiation. Unlaminated GAFCHROMIC® EBT3 film pieces, were irradiated with a 30.055 kBq 241Am alpha source, at eight different dose levels, between 0 and 509 Gy. The irradiations were performed inside an enclosed box. Epson Expression 10000 XL scanner in transmission mode was used to digitize irradiated films 24 hours post-irradiations as 16-bit RGB images in tagged image file format (TIFF). Optical density (OD) values were obtained by following the OD theorem. Raw and normalized pixel values (PVnorm) from the red, green, and blue colour channels were sampled from a 3 × 3 mm2 region of interest. Calibration curves were created for both data sets (OD and PVnorm) and were fit accordingly. Monte Carlo simulations with the Geant4 toolkit were performed to establish a dose rate at the point within the sensitive layer of the film. An alpha dosimetry protocol for EBT3 films was obtained from the Monte Carlo calculated dose rate and dose calibration curves for alpha radiation were created. It is necessary to extend this study for different film types and compare to photon dosimetry calibration curves.
Balancing cost, water, emissions, and reliability in power systems operations
Authors: Kravits Jacob , Kasprzyk Joseph R , Baker Kyri , Stillwell Ashlynn S
Published: November 2023

Traditionally, large-scale thermoelectric power generation has been operated to reduce system operational costs. To expedite the mitigation of the harmful effects of climate change, many have proposed additional incentives for system operation (i.e. policies) that incorporate greenhouse gas emissions. However, such policies rarely consider unforeseen impacts on the volumes of water required for cooling thermoelectric plants as well as the potential effects on electricity production from water/climate-related stressors. We first create a case study representative of the thermoelectric-dominated water/energy systems in the Midwestern United States. Through this case study, our analysis investigates the tradeoffs of cost, water, emissions, and reliability in thermoelectric-dominated water/energy systems via policy analysis. Furthermore, we show how such policies respond differently to historic operational, climatological, and hydrological stressors. Specifically, we find that policies that focus on a single criterion can leave power systems vulnerable to reliability issues, operational cost increases, ecological impacts on riverine systems, and increased emissions. Therefore, consideration of many criteria (cost, water, emissions, and reliability) is necessary for creating an effective water-energy-emissions policy.
Projected ENSO teleconnection on the Southeast Asian climate under global warming
Authors: Nguyen–Le Dzung
Published: November 2023

Given the importance of El Niño–Southern oscillation (ENSO) teleconnection on the Southeast Asia (SEA) climate, the ENSO-induced precipitation and near-surface air temperature anomalies over SEA and its twenty sub-regions are compared between historical (1985–2014) and future (2070–2099) simulations using 30 models from Phase 6 of the Coupled Model Intercomparison Project (CMIP6). Future projections suggest that the Philippines, Malay Peninsula, most of the Maritime Continent, and southern Indochina experience reduced (increased) precipitation in the future El Niño (La Niña) summer. Then, during autumn, amplification of ENSO-precipitation teleconnection is projected in the Borneo, Malay Peninsula, and northern Vietnam, raising flood concerns in these sub-regions in future La Niña autumn. During winter, projected ENSO-driven negative anomalies continue intensifying and shifting northeastward, resulting in drier (wetter) conditions for the Philippines and surrounding areas in future El Niño (La Niña). Conversely, a southeastward shift of ENSO-driven precipitation anomalies is projected in the following spring, leading to dampening (an amplification) of teleconnection over the western (eastern) part of SEA. Regarding near-surface air temperature, a ‘land-sea contrast’ pattern is seen, in which intensified ENSO-driven positive (negative) anomalies are projected over land (ocean). At the sub-region scale, robust amplifications in the ENSO teleconnection are mainly observed when only considering the land temperature. The most noticeable future changes are robust amplification of the ENSO-driven positive temperature anomalies in northern Indochina and Myanmar during winter. These sub-regions typically experience a cooler winter, suggesting that wintertime mean temperature there may be much higher under future El Niño conditions. The projected changes in ENSO-driven precipitation and near-surface air temperature anomalies both appear to scale with the radiative forcing, i.e. a higher radiative forcing corresponds to higher teleconnection changes and more sub-regions of SEA experience robust changes. These results suggest that significant ENSO teleconnection changes can be mitigated by minimizing future warming.
Continuous variable port-based teleportation
Authors: Pereira Jason L , Banchi Leonardo , Pirandola Stefano
Published: November 2023

Port-based teleportation (PBT) is a generalisation of the standard teleportation protocol which does not require unitary operations by the receiver. This comes at the price of requiring N > 1 entangled pairs, while N = 1 for the standard teleportation protocol. The lack of correction unitaries allows PBT to be used as a fundamental theoretical tool to simulate arbitrary channels with a general resource, with applications to study fundamental limits of quantum communication, cryptography and sensing, and to define general programmable quantum computers. Here we introduce a general formulation of port-based teleportation in continuous variable systems and study in detail the N = 2 case. In particular, we interpret the resulting channel as an energy truncation and analyse the kinds of channels that can be naturally simulated after this restriction.
Investigation on Mechanical Properties of Concrete by replacing palm Ash and fine seashell powder as Partial Cement replacement
Authors: Almaamari Janat , Fahdi Rahma Al , Jabri Fatma alzahraa Al , Kuckian Sachin
Published: November 2023

Manufacturing cement causes harm to the environment due to Co2 emissions. CO2 emission by the industry could be reduced by recycling natural waste materials such as palm ash and seashell powder; since seashell has 95% of calcium carbonate and palm ash can improve the mechanical properties. 15 cube, 3 beams were subjected to several tests to find the mechanical characteristics in a certain period. The tests were compression strength test, flexural test, workability, SEM tests, and sieving analysis. Thebeam dimensions measurements are 150mm*150mm*650mm, and 150mm*150mm*150mm for cubes. OPC was the main finding of compression strength which gained the highest strength, but in 28 days 25% of cement replacement gained 31.7Mpa when compared with other specimens. On the other hand, OPC and 5% of partial cement replacement were classified as high workability. In addition, flexural strength test showed that 15% of cement replacement achieved the highest strength compared with other specimens. SEM test showed the surface texture of PA and SP affect the hydration, therefore it will affect the strength of concrete.
Investigating the electrochemical and antibacterial activities of nickel pyrophosphate [a-Ni2P2O7] nanostructures
Authors: Mary A Juliet Christina , Santhanalakshmi M , Lavanya L
Published: November 2023

Nickel pyrophosphate nanostructures have been synthesized by a simple co-precipitation method. Annealing temperature affected the crystal structure formation of α-Ni2P2O7 and altered the surface morphology. By increasing the annealing temperature from 350 °C to 900 °C, the morphology of the material varies from irregularly shaped agglomerated particles to dumbbell-shaped nanoparticles respectively. The electrochemical performance of α-Ni2P2O7 nanoflakes (NP-2) and dumbbell-shaped (NP-3) nanoparticles is tested at 1 M KOH electrolyte solution, which provides the maximum specific capacitance of 146 and 121 F g−1 at a current density of 0.8 A g−1 respectively. Furthermore, the antibacterial activity of NP-2 nanoflakes is tested against different pathogenic Gram-positive and Gram-negative bacteria. The highest value of the inhibition zone exhibits the good antibiotic nature of the α-Ni2P2O7 nanoflakes.
Ion-acoustic waves with non-planar wavefronts
Authors: BUKHARI Shujaht , SHAHID Muhammad , RAHMAN Ata-ur
Published: November 2023

The ion-acoustic (IA) mode exhibiting various orbital angular momentum (OAM) states is examined in a plasma with drifting electrons. The constituent plasma species are modeled with a non-gyrotropic Maxwellian distribution and discussion of dispersion relation and growth rate of twisted IA waves under various conditions is presented. In the domain of kinetic model, the twisted IA waves are characterized by Laguerre-Gaussian (LG) solutions, where plasma distribution function and electric field are decomposed into axial and azimuthal components. The plasma response function is obtained under paraxial approximations and investigated for threshold condition of instability growth rate with helical electric field structures. The impact of an extra electron specie on the instability is demonstrated through a comparison of twisted waves for single and double electron species.