bluuebunny/crossref_metadata_2025 huggingface dataset:
Interference effects on wakes of a cluster of pentad square cylinders in a crossflow: A lattice Boltzmann study
Authors: Ghayoor Muhammad , Abbasi Waqas Sarwar , Majeed Afraz Hussain , Alotaibi Hammad. , Ali Ahmed Refaie
Published: December 2024

This study examines the variations in wake structures and fluid forces around a cluster of five square cylinders. The cylinders in the cluster are arranged such that a larger cylinder (the main cylinder) is surrounded by four similar but small-sized cylinders, which are very common in marine risers and axial pipe shrouds. The analysis uses an in-house developed code based on the lattice Boltzmann method. The gap spacing (g*) between the main and the surrounding cylinders varies from 0 to 10 while maintaining a fixed Reynolds number (Re) of 200. The accuracy and consistency of the code are first tested through simulations that examine the flow behind a single cylinder, revealing strong concurrence with the existing data. In the next step, the flow characteristics of the pentad arrangement are analyzed. Five diverse flow modes, including the extended single bluff body flow, stable symmetric flow, chaotic irregular shedding, antiphase symmetric flow, and modulated periodic flow, are observed depending on the gap distances. It is found that the small cylinders in the downstream position from the primary cylinder experience a negative mean drag at narrow gaps. In contrast, those at the upstream position are subjected to a positive drag force regardless of the gap spacing. The main cylinder has a higher drag coefficient compared to other cylinders for all gap spacing cases. The shedding frequencies appear similar for upstream and downstream smaller-size cylinders at higher spacing values, while the shedding frequencies for the main cylinder significantly deviate from the surrounding small cylinders.
Effect of magnetic field on THz radiation generation by self-focusing of a super Gaussian laser beam in a rippled density plasma
Authors: Amouamouha Mitra , Bakhtiari Farhad , Ghafary Bijan
Published: December 2024

Over the past three decades, much attention has been devoted to improving new methods to generate terahertz (THz) radiation. By providing ponderomotive nonlinearity in ionized plasma, the excitation of nonlinearity by laser-based techniques has emerged as a promising way for THz generation. In this paper, the concept of self-focusing of super-Gaussian laser beams has been introduced as an optimal way to generate THz radiation in plasma with a particular outlook toward the effect of applying a magnetic field to the plasma. Our analysis considers expanding the dielectric function and its higher order terms as well as paraxial ray approximation. As can be seen, magnetic field is an appropriate tool to increase the efficiency of THz self-focusing by inducing the resonance effect.
Analysis of flow characteristics and pressure pulsation in impeller region of shaft tubular pump device with different tip clearances
Authors: Sun Shengjie , Jin Xiaoyu , Lin Zhikang , Shao Chunlou , Wang Hao , Yang Fan
Published: December 2024

The shaft tubular pump device (STPD) impeller flow characteristics and occurrence regularity of tip clearance leakage (TCL) flow were investigated using a steady and unsteady three-dimensional numerical simulation with computational fluid dynamics as the basis. The energy performance, internal flow characteristics, and pressure pulsation characteristics of the STPD under various tip clearance widths were examined. The results indicate that the performance of STPD is negatively impacted by an increase in tip clearance width. With an increase in tip clearance width from 0.2 to 0.5 and 1.0 mm, the efficiency of the STPD decreases by 1.57% and 3.13%, respectively, when flow coefficient is 0.49. Tip clearance width variation has less of an impact on the impeller inlet’s flow, especially the velocity distribution. When tip clearance width grows, the flow pressure pulses from impeller flange to hub side. Meantime, the unstable region at the impeller shifts from the rim to the hub, and TCL flow develops outward to the nearby blades. As flow rate increases, tip clearance width has a gradually decreasing effect on flow.
Quantitative study of local defects by pulsed eddy current testing
Authors: Li Zhaoyang , Dong Liang
Published: December 2024

Pulsed eddy current testing (PECT) is a non-destructive evaluation technique capable of detecting defects within conductive materials; however, it often encounters challenges in accurately quantifying localized defects. This paper introduces a novel methodological approach and theoretical framework for the identification and quantification of such defects using a high-resolution focusing probe. The effective coverage area of the focusing probe is characterized by a two-dimensional Gaussian distribution model, enabling a detailed analysis of the probe’s interaction with the material under test. Analytical formulas are derived to describe the detection process, providing a foundation for subsequent error analysis. To optimize the detection process, four distinct types of error functions are formulated, and an optimization algorithm is employed to determine the parameters that minimize these error functions. This approach ensures that the probe settings are tailored to the specific characteristics of the defects being investigated. Simulation data are utilized to invert the probe parameters and extract defect information, thereby validating the feasibility and accuracy of the proposed method. The simulation results demonstrate that the method presented in this paper can effectively quantify defects with a high degree of precision. In conclusion, the research presented in this paper offers a significant advancement in the field of PECT by providing a robust method for the accurate quantification of localized defects. This contribution is expected to enhance the reliability and applicability of PECT in various industrial applications where the detection and quantification of defects are critical.
Garbage classification detection system based on the YOLOv8 algorithm
Authors: Zhou Yan , Lin Lixiong , Wang Tong
Published: December 2024

To solve the problem of diverse types of household garbage that are difficult to classify accurately, a neural convolutional network-based garbage classification system that can be used for validation on unmanned vehicles is proposed. First, the garbage is classified into 44 categories by examining public datasets, which were combined with the actual collected data to build a comprehensive dataset that generated and labeled 15 000 images. Subsequently, the YOLOv8 algorithm is studied, applied to garbage detection and classification, and used for practical verification in unmanned vehicles. Experimental results show that the trained model has a speed of ∼35 f/s and a recognition accuracy of 90%. Finally, due to the real-time performance requirements of unmanned vehicles, the dataset was retrained, and the YOLOv8 weight model was investigated. The model was deployed on the Jetson Xavier NX development platform and integrated into unmanned vehicles to enable automatic garbage recognition and tracking.
Fluctuating charge-density-wave correlations in the three-band Hubbard model
Authors: Mai Peizhi , Cohen-Stead Benjamin , Maier Thomas A. , Johnston Steven
Published: December 2024

The high-temperature superconducting cuprates host unidirectional spin- and charge-density-wave orders that can intertwine with superconductivity in nontrivial ways. While the charge components of these stripes have now been observed in nearly all cuprate families, their detailed evolution with doping varies across different materials and at high and low temperatures. We address this problem using nonperturbative determinant quantum Monte Carlo calculations for the three-band Hubbard model. Using an efficient implementation, we can resolve the model’s fluctuating spin and charge modulations and map their evolution as a function of the charge transfer energy and doping. We find that the incommensurability of the charge modulations is decoupled from the spin modulations and decreases with hole doping, consistent with experimental measurements at high temperatures. These findings support the proposal that the high-temperature charge correlations are distinct from the intertwined stripe order observed at low-temperature and in the single-band Hubbard model.
Regulation of ROS signaling by TIGAR induces cancer-modulating responses in the tumor microenvironment
Authors: Cheung Eric C. , Strathdee Douglas , Stevenson David , Coomes Jack , Blyth Karen , Vousden Karen H.
Published: December 2024

The consequences of reactive oxygen species (ROS) in cancer cells are complex and have been shown to both promote and retard tumorigenesis in different models. In mouse models of pancreatic ductal adenocarcinoma (PDAC), loss of the antioxidant defense gene
Tigar
results in both a reduction in the development of early pancreatic intraepithelial neoplasia and an increase in invasive and metastatic capacity, accompanied by decreased survival of mice lacking pancreatic TIGAR. We previously demonstrated that increased ROS following loss of TIGAR promotes various cancer cell–intrinsic changes that contribute to metastatic capacity, including epithelial to mesenchymal transition, enhanced migration and invasion, and an increase in ERK signaling. In this study, we show that pancreatic overexpression of TIGAR decreases metastatic capacity and migratory phenotypes in an aggressive model of PDAC, consistent with the concept that dynamic modulation of TIGAR in PDAC contributes to the development and progression of these tumors. Using TIGAR deficient and overexpressing mouse models, we find that the impact of modulation of TIGAR and ROS in PDAC cells also has a profound effect on the normal stromal cells surrounding the tumor. Loss of TIGAR promotes the production of cytokines by cancer cells that induce changes in the surrounding fibroblasts to adopt a tumor-supportive phenotype. Furthermore, these cytokines also attract macrophages that support PDAC dissemination and metastasis. Taken together our work shows that TIGAR-modulated ROS in PDAC can control cell intrinsic and extrinsic changes to impact tumor aggression.
On word stress in Mandarin
Authors: Yan Fang
Published: December 2024

Qingsheng and qingyin have
long been a set of confusing concepts in Chinese linguistic studies. In
literature scholars usually agree on the use of qingsheng to
refer to the neutral tone in Mandarin. However, some scholars believe that
qingsheng is the same as qingyin and use
them interchangeably. Furthermore, the term qingyin is used to
prove that Mandarin has word stress, since word stress, or
zhongyin in Chinese is the counterpart of
qingyin. Therefore, it is important to clarify the
relationship between the two concepts, namely qingsheng and
qingyin to determine the linguistic and typological nature
of Mandarin. This study tried to differentiate these two concepts both
phonetically and phonologically and proved that qingsheng is a
result of a set of tonal processes, such as tone sandhi, tone neutralization,
tone spreading, while qingyin is a result of a series of
metrical process, such as clash and lapse. It also compared
qingsheng and qingyin on their functions,
classifications, origins, and did a quantitative study on the distribution of
the qingsheng words in Mandarin to further prove that
qingsheng and qingyin are two completely
different concepts, and hence proved that it is invalid to claim Mandarin has
word stress because of the existence of qingsheng.
Social media, politics, and the rise of the anti-refugee far-right in Turkey
Authors: Efe İbrahim , Ülker Osman
Published: December 2024

This paper examines the discursive strategies of Turkey’s emerging far-right political party, the Zafer Partisi
(Victory Party). The Party’s leader, Ümit Özdağ, gained unexpected electoral influence in 2023, prominently advocating for the
expulsion of Syrian refugees. Combining content and critical discourse analysis, the paper delves into the discursive features of
Özdağ’s tweets on refugees. Subsequently, it aims to understand the intricacies of the party’s anti-refugee stance within the
context of Turkish politics and its implications for relationships between Turkish society and refugees. The dataset comprises
3008 tweets spanning from November 18, 2022, to November 18, 2023. The analysis reveals Özdağ’s construction of a securitization
narrative, framing refugees as a threat and positioning his party as the defender of Turkish identity. His far-right stance,
distinguishes itself by strategically targeting Syrian refugees, appealing to public concerns, and casting suspicions on local and
international actors, specifically the ruling party in Turkey and the EU.
Farmers as symbol of ‘the people’
Authors: Lambrechts Gijs , De Cleen Benjamin
Published: December 2024

Despite increased attention to the far right and environmental issues, little research has focused on the
increasingly prominent attempts by populist radical right (PRR) parties to capitalize on farmers’ protests against climate and
biodiversity policies across Europe. This article addresses this gap by analyzing PRR discourse through a case study of the
Flemish PRR party, Vlaams Belang (VB), a party that has only recently started to present itself as the defender of farmers and
rural populations. A discourse-theoretical analysis of VB’s 2019–2024 publications on farmers and agriculture reveals that VB
employs the ‘the rural’ as a symbolic signifier to integrate farmers and their demands into its discourse. The party constructs
farmers as the symbol of ‘the people’ through both nationalism and populism. Through their link with ‘the rural,’ farmers are
positioned as rooted in ‘the nation’ within VB’s nationalist politics and as part of ‘the underdog’ in its populist politics.
Design and analysis of a proposed inorganic a-Si/Sb2S3 near-infrared narrowband photodetector
Authors: Ahmed Ibrahim S , Qaid Saif M H , Elogail Yasmine , Asemi Nassar , Ahmed Abdullah Ahmed Ali , Shaker Ahmed
Published: December 2024

There is a significant demand for narrowband photodetectors (NBPDs) operating within the near-infrared (NIR) wavelength range (650 and 900 nm) in various applications, especially in biomedical sensing. In this TCAD computational study, a filter-less NBPD employing a p-n heterojunction a-Si/Sb2Se3 architecture is designed and analyzed. The pivotal aspect of this photodetector lies in its hierarchy, with structure featuring a wider bandgap amorphous silicon (a-Si) material having a thicker layer followed by a slightly narrower bandgap Sb2Se3 material with a shorter film. The detector inorganic architecture FTO/a-Si/Sb2Se3/Au is established within SCAPS-1D numerical simulations, following an experimentally validated NIR NBPD based on CdSe/Sb2(S, Se)3. Simulation results demonstrate that the presented NBPD design exhibits adequate performance with a thickness of 7.0 µm for the a-Si layer and an Sb2Se3-layer thickness of 1.2 µm, achieving a selective spectral response at 684 nm having a full width half-maximum (FWHM) of 35.4 nm and a photoresponsivity of approximately 0.389 A/W under no bias conditions. This a-Si/Sb2Se3 NBPD efficiently detects wavelength range of 650 to 725 nm, offering valuable insights for the development of filter-less low-cost eco-friendly NIR NBPD. Additionally, the proposed structure eliminates the need for an organic hole transportation layer, thereby enhancing the detector stability.
Tunable slow-light with different definitions of velocity on isolated graphene
Authors: Abdollahi Mohammad Amin , Moradi Gholamreza , Askarpour Amir Nader
Published: December 2024

We numerically investigate surface wave propagation in an isolated graphene sheet, an extremely dispersive medium, for tunable slow-light. This surface wave is tightly confined to the graphene. The propagation velocity of this wave is calculated in five different ways. These velocities are phase velocity, group velocity, energy velocity, centro-velocity, and cross-correlation velocity. Calculations show that except for the group velocity, all the introduced velocities are in the same range, whereas the group velocity is significantly different from others. However, in the literature, the definition of slow-light is based on the group velocity. So, it seems that providing a new terminology for slow-light is necessary. In defining this new terminology, we attempt to choose velocities with the best-quantified pulse velocity description with two critical features: proper physical interpretation and measurability. It is found that the velocities in the time domain provide more acceptable performance and are more physically meaningful than the velocities in the frequency domain.
Numerical calculation of N-periodic wave solutions to two kinds of generalized (2+1)-dimensional KdV-type equations
Authors: Xin Pengcheng , Zhao Zhonglong , Wang Yu , Guo Zun-Guang
Published: December 2024

In this paper, by combining the direct method proposed by Nakamura with the numerical algorithms, the N-periodic wave solutions of two kinds of (2+1)-dimensional KdV-type equations are investigated, which are applied in fluid dynamics and plasma physics. The problem of solving N-periodic wave solutions can be transformed into a least squares problem and addressed by using numerical algorithms. The three- and four-periodic wave solutions of the KdV-type equations are obtained and some numerical results are presented. It is verified that the N-periodic wave solutions approach to the N-soliton solutions under a small amplitude limit. The dynamic behaviors of the quasi-periodic wave solutions are analyzed by utilizing the characteristic lines. The numerical procedure adopted in this paper can be further generalized to other high-dimensional nonlinear integrable systems.
Numerical simulation and experimental investigation of the propagation law of plasma pulse shock waves
Authors: Fang Song , Wang Jin , Zhang Yuanyuan , Li Hufeng , Liu Jiawei , Xue Qilong
Published: December 2024

Plasma pulse shock wave rock-breaking technology represents a novel approach to rock fracturing. Present research on this subject largely addresses rocks and electrodes, yet often neglects the critical influence of shock waves in the rock-breaking process. Therefore, it is necessary to further study the propagation law of the shock wave and its reflection and transmission. This paper undertakes experimental simulations using the RHT rock model to explore the propagation process of plasma pulse shock waves based on two variables: the medium and the shape of the electrode. Integrated with one-dimensional stress wave theory, the study examines the impact of four specific parameters—dielectric thickness, surrounding rock height, surrounding rock density, and surrounding rock porosity—on the reflection and transmission rates of shock waves. Pressure data collected from experimental platform are utilized to validate the study’s conclusions. The findings indicate that the propagation behaviors of shock waves differ significantly between water and air mediums. The shape of the electrode causes significant differences in the pressure exerted by the shock wave at the same location. Both the thickness of the dielectric and the porosity of the surrounding rock show a positive correlation with the reflection coefficient and a negative correlation with the transmission coefficient, while the density of the surrounding rock exhibits an inverse relationship. The height of the surrounding rock is irrelevant to both reflection and transmission coefficients.
UAV detection in complex background with multi-scale feature fusion enhancement and channel-weight matching up-sampling
Authors: Zhang Huijuan , Li Kunpeng , Ji Miaoxin , Liu Zhenjiang , Zhang Chi , Yu Yuanjin
Published: December 2024

The reckless flight of unmanned aerial vehicle (UAV) seriously threatens the public and aviation safety. Due to their small size and unobvious features, it remains a great challenge for the current detection algorithms to detect UAV, especially in complex backgrounds with backlighting. To address these issues, the multiscale feature fusion enhancement strategy and channel-weight matching (CWM) rule are proposed in this paper. A multiscale feature fusion enhancement strategy is presented to capture the multi-scale contextual information, which not only suppresses information conflicts but also enhances feature extraction capabilities. Then, an up-sampling method based on CWM is designed to enhance the sensitivity of small object, which uses different up-sampling techniques based on the importance level of each feature channel. Finally, a feature refinement module for small object is designed to further enhance the characterization of their features. The ablation and comparative experiments are carried out on the self-made UAV dataset. Compared to the original YOLOv5 algorithm, the proposed method shows an increase of 3.6% in mAP0.5 and 2.8% in mAP0.5:0.95, respectively. Moreover, the comparative experiments are implemented on the VisDrone2019 dataset, and the results indicate that the mAP0.5 and mAP0.5:0.95 of the proposed method also increase by 4.2% and 1.6%, respectively.
Enhanced electro-optical performance of barium oxide stacked layers via platinum nanosheets designed for wide band light absorption and terahertz technology
Authors: Gaabour Laila H , Qasrawi A F , Alharbi Seham R
Published: December 2024

In this study, stacked films of barium oxide (BaO) comprising platinum nanosheets in its structure are designed as electro-optical filters applicable in terahertz technology. The layers were fabricated by the thermal evaporation technique. It was shown that insertion of 50 nm and 100 nm thick Pt nanosheets between stacked layers of BaO improves the crystallinity of the layers by reducing the strains and defect concentrations. In addition, the light absorption and optical conduction is enhanced by more than 300%, 900% and 100% in the ultraviolet (3.5–4.10 eV), visible (1.80–3.10 eV) and infrared (1.10–1.75 eV) ranges of light, respectively. The insertion of Pt nanosheets led to an increase in the dielectric constant

ε

r

values by over 104%. Specifically,

ε

r

values were initially 1.2–1.5, 1.6–1.8, and 1.8–2.0 in the ultraviolet, visible, and infrared light ranges, respectively. Upon incorporating Pt nanosheets with a thickness of 200 nm, these

ε

r

values increased to 1.4–1.7 in the ultraviolet, 1.8–3.6 in the visible, and 3.7–3.9 in the infrared ranges. Significant increase in the terahertz cutoff frequency from ∼2.5 THz to ∼15.35 THz was achieved in the infrared range of light. Moreover, the optical conductivity parameters which were obtained with the help of Drude–Lorentz electro-optical analysis showed remarkable enhancement in the free carrier concentration and in the drift mobility of the BaO optical filters from 5

×

10

18

cm−3 and 0.47 cm2 Vs−1 to 7

×

10

18

cm−3 and 2.03 cm2 Vs−1 to 9

×

10

18

cm−3 and 2.03 cm2 Vs−1 upon insertion of Pt nanosheets of thicknesses of 100 nm and 200 nm, respectively. Furthermore, the temperature dependent electrical conductivity measurements has shown that Pt nanosheets increased the electrical conductivity of BaO by eight orders of magnitude. The features of BaO stacked layers comprising Pt nanosheets are promising for terahertz technology applications as waveguides and wideband optical filters.
Solutions and quantum dynamics of the quantum Rabi model with A-square terms
Authors: Chen Xiang-You , Ye Tian , Chen Qing-Hu
Published: December 2024

It is well known that the A-square term must be considered in both cavity and circuit quantum electrodynamics systems, because it arises in the derivation from the minimal coupling Hamiltonian at any finite coupling strength. In this paper, we study the quantum Rabi model with A-square terms using the Bogoliubov operator approach. After a unitary transformation, the A-square terms can be eliminated, resulting in a modified quantum Rabi model with renormalized parameters. A transcendental function responsible for the exact solution is then derived. The presence of the A-square terms is found to significantly alter the energy spectrum. The dynamics are also studied using the obtained exact wave function, which is sensitive to the strength of the A-square terms at strong coupling. We believe that these results could be observed in future light–matter interaction systems in the ultra-strong and deep strong coupling regimes.
Exploring the impact of SRSL strategies on conceptual understanding in physics: A study on first-year students using FCI
Authors: Sari I M , Zakwandi R , Medellu N C , Prakoso A S , Aviyanti L
Published: December 2024

Academic adaptation is a primary challenge new students face at nearly every university. The differences in learning culture between high school and higher education’s more independent learning environment significantly impact academic success, particularly in the first year. This study aims to analyze the effects of implementing the Self-Regulated Approach to Strategic Learning (SRSL) on the conceptual understanding of first-year physics students. The study focuses on topics evaluated using the standard Force Concept Inventory (FCI) test. Each respondent completed two questionnaires, one during the planning phase and one during the implementation phase, while studying three topics related to the FCI. The research data were analyzed qualitatively to assess students’ ability to plan and implement learning strategies and quantitatively to measure conceptual understanding through FCI scores. The results indicated that students could reasonably perform situational analysis of learning contexts. However, they needed help to implement the learning strategies they had planned. Post-learning, students also faced difficulties evaluating the challenges encountered during strategy implementation (comprehensive monitoring and problem-solving) and determining appropriate corrective actions (modification). These difficulties were reflected in the low cognitive category on the FCI. This finding suggests difficulties executing and modifying learning strategies affect first-year students’ conceptual understanding. Therefore, improvements are needed in classroom teaching and providing out-of-class guidance to help students design and implement effective learning strategies at the university level.
Students’ scientific argumentation skills through PjBL–STEAM model assisted by web-based interactive PowerPoint on static fluid
Authors: Rachmawati O Q , Parno  , Latifah E , Wisodo H , Ghorbiy B , Bunyamin M A H
Published: December 2024

Providing scientific arguments is essential during physics learning, specifically in studying static fluid material. However, students’ scientific argumentation skills still need to improve. So far, project-based learning methods that include STEAM using specific media have not improved scientific argumentation abilities. This study investigates students’ scientific argumentation skills after participating in PjBL–STEAM learning assisted by Web-based Interactive PowerPoint on static fluid. This study, which involved 30 students in class XI MIPA at one of the high schools in East Java – Indonesia, employed a mixed-method approach with an embedded experimental design. The instrument comprises the Static Fluid Scientific Argumentation Test, which consists of five essay questions, interviews, and observation guides. It is a quantitative data analysis using the Wilcoxon test, N-gain, and Effect Size. Concurrently, qualitative data analysis involves reducing data, classification, and conclusion. The responses from the students will then be divided into five categories, levels 1–5 scientific argumentation. N-gain score of 0.37 (medium) and effect size of 0.87 (large) in the data supported the idea that students’ scientific argumentation greatly improved. Through learning activities, students’ arguments could improve from level 3 on the pre-test to level 5 on the post-test. In this case, a few students still have difficulties with the backing aspect of the sub-topic of Pascal’s law and rebuttal for the sub-topic of Archimedes’ law. However, most students could support scientific argumentation skills by connecting facts, supporting statements, and applying knowledge in real-world situations. For future research, students should be trained in writing the backing and rebuttal components and add a control class.
Magnetic moment in hexagonal Boron Nitride (h – BN) with Carbon doping: Density functional theory study
Authors: Nenohai A J W T , Santana F M , Arifin R , Asih R , Darminto
Published: December 2024

As a 2D material continuously being researched, h-BN is a unique material with the potential to develop its applications. Basically, h-BN is an insulating and non-magnetic material. However, in its development, this material can become a candidate in the fields of energy to optoelectronic devices. This can be achieved by modifying the h-BN structure by providing various defect models. In this study, we modified the 4 × 4 × 1 h-BN structure with C doping in h-BN to determine the magnetic and electrical properties in h-BN doped with C atoms. Our calculations are based on Density Functional Theory with the Generalized Gradient Approximation – Perdew – Burke – Ernzerhof correlation exchange function. This C doping replaces several N atoms in the h-BN layer. The results obtained are the emergence of magnetic moment values that induce the magnetic properties of h-BN. The existing magnetic properties will provide opportunities for the development of h-BN.
Profile of critical thinking skills of senior high school students in physical wave material
Authors: Lintangesukmanjaya R T , Prahani B K , Suliyanah  , Sunarti T , Saphira H V
Published: December 2024

This research investigates using learning methods and teaching media on students’ critical thinking skills. The results of the test instruments given to class XI students at Public high school Cerme are that students have not yet mastered essential skills of thinking, including clarification, evaluation, analysis, interpretation, and inference in physics lessons regarding waves and their characteristics using the learning methods currently used by the teacher. Students’ concerns in answering questions lie in needing to be more optimal in understanding the concepts in the material, as well as using media and learning methods that are less effective. Guided inquiry learning relevant to open media can be an alternative solution to improve students’ critical thinking skills. In the future, digital media innovation, which is equipped with a guided inquiry learning model, will change the essential thinking skills of students at Public high schools in learning physics. This research is important in maximizing the application of technology in digital-based learning as innovative learning planning.
Learning physics through the traditional game Egrang in junior high school
Authors: Kuswanto H , Rahmat A D
Published: December 2024

Integrating the traditional game ‘Egrang’ can serve as an effective method for teaching physics concepts to junior high school students. This study identifies the physics concepts in traditional games Egrang and students’ opinions regarding experiential learning in reconstructing scientific knowledge. This study uses a qualitative method using interviews to collect data. This study’s participants were 25 8th-grade junior high school students from West Java, Indonesia. The study procedure is teachers explaining learning activities, students exploring Egrang, discussing physics concepts, and interviewing. Then, six students were randomly selected for interviews. The result of the study indicates that students can find the concepts of motion and force through the exploration of Egrang. Students can describe how to play Egrang by incorporating physics concepts. The interview results found that students prefer outdoor learning and find it to be a valuable experience in their surrounding environment. Learning physics through traditional games facilitates students’ understanding of physics concepts and creates meaningful learning. Even though some students could not successfully play Egrang, they could still have experiences by observing their surroundings. These findings suggest that traditional games like Egrang can effectively enrich physics education, promoting academic achievement and cultural awareness.
Optimization heating time of CaCO3 calcite phase from Bangkalan dolomite
Authors: Anjani R D , Rohmawati L , Kusumawati D H , Fitriana  , Putri N P , Rahmawati D A
Published: December 2024

Calcium carbonate (CaCO3) is a natural inorganic biomaterial obtained from Bangkalan dolomite containing 63.42% CaCO3 and 26.39% MgO. Calcium carbonate has three polymorphs, namely calcite, aragonite, and vaterite. Calcite is the most stable phase of CaCO3 and is widely used in various fields. Several studies have used the leaching method in synthesizing CaCO3 within 24 hours of heating; a mixed phase was still obtained, namely 87.31% calcite and 12.69% vaterite. Therefore, this research was conducted to analyze the effect of long heating time on the CaCO3 calcite phase, which was synthesized using the leaching method. The leached samples were heated with varying heating times at a temperature of 60°C, namely 24 hours, 2×24 hours, and 4×24 hours. This research produces the main calcite phase after heating for 4×24 hours without any other phases. It has a crystallite size of 35.79 nm, classified as nanocrystalline. Thus, calcite CaCO3 The results produced can later be applied in the medical and industrial fields.
Simulation of Cadmium (Cd) detection in palm oil using optical fiber sensors
Authors: Anargiansyah M B , Pramudya F R A , Fayensi B R P , Hikmah R N , Ghani M F , Khoiro M
Published: December 2024

The detection of Cadmium (Cd) in palm oil using optical fiber sensors had been simulated utilizing the Finite Element Method (FEM) approach to investigate sensor performance. The optical fiber sensor was developed using chitosan reagents for better detection performance. The optical fiber was built using a silica core with a refractive index of 1.45, and cladding was replaced by the result reaction between chitosan and oil with a refractive index of 1.333. The study aims to observe the effect of reagent thickness that varied 0.1 to 0.5 mm for sensor performance to detect Cd in oil with a concentration variation of 0.05 - 0.5 ppm using a 650 nm red beam source. The results show that increasing the reagent’s thickness can reduce the beam’s confinement factor in optical fiber from 90.224 to 61.975. The reduction can be due to the mismatching of the refractive index between the core and cladding. The performance of the optical fiber sensor was examined using loss propagation and confinement factor in Cd concentration variation. For each reagent thickness, the results indicated that the loss propagation increased, and on the contrary, the confinement factor decreased as Cd concentration increased. The highest sensitivity of the sensor, calculated from the slope of the concentration vs. confinement factor graph, was obtained while using 0.5 cm reagent thickness with the value of 1.6267. It indicated that the reagent thickness could improve the optical fiber sensor performance, especially on Cd detection in oil.
The sintering temperature effect of Alumina (Al2O3) ceramic using the sol-gel method
Authors: Suaebah E , Yunata E E , Wijaya A S N
Published: December 2024

Aluminum Oxide (Al2O3) or alumina nanoceramics were synthesized by sol-gel method. The effect of sintering temperatures on the microscopic properties of alumina has been investigated by X-ray diffraction (XRD), Ultraviolet Visible (UV-Vis), and Particle Size Analyzer (PSA). The XRD result confirms the formation of γ-Al2O3 at 600 °C and 800 °C and the formation of α-Al2O3 at 1000°C, respectively. The microscopic particle size structure of alumina at 600 °C, 800 °C and 1000 °C sintering was confirmed at micro size from 236, 370.6, and 754.1 nm, respectively. The UV-Vis result shows the absorption peak of Aluminum Oxide (Al2O3) in the range 190 to 230 nm. The result of particle size shows that the sol-gel method of alumina in different sintering temperatures shows the best result of the sintering process at 1000 °C. The optimal result was conducted at a sintering temperature of 1000 °C because it exhibits the α-Al2O3 (corundum) phase with very high and visible diffraction peaks. From the data obtained, it is known that the α-Al2O3 phase can occur at temperatures above 1000 °C.
Effect of compaction pressure on shrinkage, density, and hardness of strontium hexaferrite
Authors: Widodo R D , Darsono F B , Fitriyana D F , Rusiyanto  , Widayat W , Nuryanta M I , Kriswanto  , Rudianto I
Published: December 2024

Iron sand as a magnetic material has yet to be widely used; in several developed countries, magnetic materials are already commonly used in industry. A simple method for purifying iron sand is carried out by filtering iron sand with a mesh size of 80. The quality of this magnetic base material is influenced by, among other things, its density and hardness. The research aims to determine the effect of compaction pressure on the shrinkage, density, and hardness of iron sand-based strontium ferrite. The iron sand from Ketawang Indah Beach, Purworejo, was extracted mechanically 35 times with a permanent magnet and then oxidized at a temperature of 900 °C for 5 hours. Next, the iron oxide was mixed with strontium carbonate (SrCO3) using a shaker mill for 3 hours. The resulting strontium ferrite powder was compacted at 20, 40, and 60 MPa pressures, then sintered at 1100 °C for 1 hour in a furnace. Shrinkage measurements include the diameter and height of the specimen, while density measurements use the Archimedes method. The hardness obtained through the Vickers hardness, the highest shrinkage value was obtained at a pressure of 20 MPa, namely diameter shrinkage (Δd) of 2.6% and height shrinkage (Δh) of 0.5%. The highest density and hardness values were at a pressure of 60 MPa, 4.366 g/cm3, and 693 HV. An increase in pressure at a sintering temperature of 1100 °C causes a decrease in shrinkage and an increase in density and hardness values.
Impact of the fiber-optic faceplate on the imaging performance of a CMOS X-ray detector
Authors: Yoo Seungjun , Park Seongbon , Yun Seungman , Kim Ho Kyung
Published: December 2024

Complementary metal-oxide-semiconductor (CMOS) active-pixel
detectors are widely used in various imaging applications owing to
their faster operation with lower noise and higher sensitivity than
their conventional amorphous silicon-based counterparts. However,
CMOS detectors are vulnerable to radiation damage owing to their
crystalline structures. They also suffer from ghosting artifacts
and gradual reduction of dynamic range along with their
lifetime. Most CMOS detectors employ a fiber-optic faceplate (FOP)
between the X-ray converter and CMOS active-pixel array to mitigate
the radiation effect and increase longevity. In this study, we
investigated the effect of an additional FOP layer on the imaging
performance of a CMOS detector, including the modulation-transfer
function (MTF), noise-power spectrum (NPS), and detective quantum
efficiency (DQE). For X-ray energies ranging from 40 to 70 kV, we
measured the large-area signal-transfer functions, MTFs, and NPSs
and calculated the corresponding DQEs. The FOP degraded the MTF
performance over the entire spatial frequency, but improved the NPS
performance with increasing spatial frequency. Consequently, the FOP
layer enhanced the DQE performance for the given energy ranges. The
measured results are discussed in detail using a theoretical
cascaded-systems model.
An experimental and computational evaluation of a novel Timepix3 detector for Compton imaging in nuclear medicine
Authors: Kamtchou B. , León Vintró L. , Cournane S.
Published: December 2024

In this paper, we investigate the use of a MiniPIX
(Timepix3) hybrid pixel detector as a single layer Compton camera
for low-energy (< 200 keV) photons for Nuclear Medicine imaging
applications. Literature to date has focused on using Compton camera
imaging for high energy photons emitted from non-clinically relevant
radionuclides. This paper aims to investigate Compton imaging for
nuclear medicine specific radionuclides such as Tc99m
(140 keV). For this, a Timepix3 chip with a 1 mm CdTe sensor has
been fully characterised in terms of efficiency, energy and timing
resolution using a range of point sources, and a detailed model of
the detector developed using the EGSnrc Monte Carlo
toolkit. Knowledge of the specific interaction points within the
detector in the simulation allowed a prediction to be made of the
performance of the detector as a Compton camera. Comparison with
experimental measurements showed good agreement with simulations,
providing validation of the methods employed for image
reconstruction.

Simple Back Projection (SBP), Filtered Back Projection (FBP) and
List Mode-Maximum Likelihood Expectation Maximisation (LM-MLEM)
techniques were used for image reconstruction. For all experimental
acquisitions, measured Full Width Half Maximum (FWHM) values were
within 6% of the modelled values, with Doppler broadening
identified as the main limiting factor of the spatial resolution of
the system. LM-MLEM consistently returned the highest spatial
resolution images, with a 7.3 ± 0.5 mm FWHM achieved for
99mTc point sources, consistent with current clinical gamma
cameras. Our results demonstrate the potential of the Timepix3 as a
single layer CdTe Compton camera for clinical applications using low
energy gamma emitters. The developed MC model will provide a means
of investigating larger area, single layer CdTe Compton cameras for
nuclear medicine imaging.
Spatial heterogeneity of ecosystem services and their valuation across himalayas: a systematic literature review and meta-analysis
Authors: Sharma Prakhar , Prashanth Swathi S , Sharma Ashutosh , Sen Sumit
Published: December 2024

The Mountain Ecosystems, such as the Himalayan region, not only provide numerous Ecosystem Services (ESs) to millions of people living in mountainous areas but also provide essential ES to those living downstream. However, there is often an uneven distribution of ES availability and its value across different regions. Therefore, a better understanding of the spatial heterogeneity of ES is required for efficient and sustainable management of ES. This study thoroughly reviews literary data to examine ES’s spatial distribution and economic values across the Western, Central, and Eastern Himalayas. The literature was searched in the Scopus online database using the Boolean method from specific keywords such as ‘Ecosystem Services’ AND ‘Himalayas’. A systematic review of 76 of the most relevant literature sources yielded 31 unique ES divided into three categories: Provisioning (PES), Regulating (RES), and Cultural (CES). The distribution of reviewed literature is relatively balanced across the Himalayas (Western: 30.26%, Central: 32.89%, Eastern: 36.84%); however, the analysis identified a bias towards PES (43.54%), highlighting a need for increased research focus on RES (36.48%) and CES (19.98%). Notably, water-related services such as PES9 (Surface water used as a material (non-drinking purposes)) and PES8 (Surface water for drinking) have been ranked highest in all regions of the Himalayas yet have not been comprehensively studied in terms of their quantification and valuation. Furthermore, while most literature focused on the identification of ES (73.68%), there is a significant lack of attention to quantification (39.47%) and valuation (23.68%) of ES in the region. The average economic values for PES, RES, and CES were 446.75 USD/ha/year, 1128.81 USD/ha/year, and 457.51 USD/ha/year, respectively, indicating higher valuation for RES. This underlines the need for a more balanced research approach that includes identifying and thoroughly quantifying and valuing all types of ES in the Himalayas.
Molecular breath profile of acute COPD exacerbations
Authors: Basler Sarah , Sievi Noriane A , Schmidt Felix , Fricke Kai , Arvaji Alexandra , Herth Jonas , Baur Diego M , Sinues Pablo , Ulrich Silvia , Kohler Malcolm
Published: December 2024

Acute exacerbations of chronic obstructive pulmonary disease (AECOPD) show high variability in individual susceptibility and promote disease progression; thus, accurate diagnosis and treatment is essential. Unravelling the molecular metabolic changes during AECOPD in breath could promote understanding of AECOPD and its treatment. Our objective was to investigate the metabolic breath profiles during AECOPD for biomarker detection. We conducted real-time breath analysis in patients with COPD during AECOPD and during subsequent stable phase. Molecular breath patterns were compared between AECOPD and stable phase by dimension reduction techniques and paired t-tests. Pathway enrichment analyses were performed to investigate underlying metabolic pathways. Partial least-squares discriminant analysis and XGboost were utilised to build a prediction model to differentiate AECOPD from stable state. 35 patients (60% male) with a mean age of 65 (10.2) yr with AECOPD were included. AECOPD could be predicted with a high sensitivity of 82.5% (95% confidence interval of 68.8%–93.8%) and an excellent discriminative power (AUC = 0.86). Metabolic changes in the linoleate, tyrosine, and tryptophan pathways during AECOPD were predominant. Significant metabolic changes occur during COPD exacerbations, predominantly in the linoleate, tyrosine, and tryptophan pathways, which are all linked to inflammation. Real-time exhaled breath analysis enables a good prediction of AECOPD compared to stable state and thus could enhance precision of AECOPD diagnosis and efficacy in clinical practice.
Shotgun metabolomic analysis of killer whale (Orcinus orca) exhaled breath condensate
Authors: Harsla Trevor R , Breitzman Matthew W , Showman Lucas J , Robeck Todd R , Staggs Lydia A , Russell Jennifer P , Schmitt Todd L , Steinman Karen J , McGill Jodi L , Lippolis John D , Sacco Randy E
Published: December 2024

The ocean is facing many anthropogenic stressors caused from both pollution and climate change. These stressors are significantly impacting and changing the ocean’s ecosystem, and as such, methods must continually be developed that can improve our ability to monitor the health of marine life. For cetaceans, the current practice for health assessments of individuals requires live capture and release, which is expensive, usually stressful, and for larger species impractical. In this study, we investigated the potential of exhaled breath condensate (EBC) samples to provide unique metabolomic profiles from healthy killer whales (Orcinus orca) of varying known age and sex. EBC collection is a non-invasive procedure that has potential for remote collection using unmanned aerial vehicles, thus improving our ability to understand physiologic parameters within wild populations while minimizing stress from collection procedures. However, descriptions of the available metabolome within EBC and its clinical significance within animals of known health and age must be described before this technique can be considered diagnostically useful. We describe normal variations of the metabolome across age and sex and provide evidence for the potential of this breath analysis method to become a valuable adjunctive tool for assessing the health of managed-care and free-ranging killer whales.