bluuebunny/crossref_metadata_2025_split huggingface dataset:
Interatomic Coulombic decay in lithium-doped large helium nanodroplets induced by photoelectron impact excitation
Authors: Ben Ltaief Ltaief , Sishodia Keshav , Asmussen Jakob Dall , Abid Abdul Rahman , Krishnan Sivarama , Pedersen Henrik B , Sisourat Nicolas , Mudrich Marcel 
Published: January 2025

Abstract
Irradiation of condensed matter with ionizing radiation generally causes direct photoionization as well as secondary processes that often dominate the ionization dynamics. Here, large helium (He) nanodroplets with radius ≳ 40 nm doped with lithium (Li) atoms are irradiated with extreme ultraviolet (XUV) photons of energy hν ≥ 44.4 eV and indirect ionization of the Li dopants is observed in addition to direct photoionization of the He droplets. Specifically, Li ions are efficiently produced by an interatomic Coulombic decay (ICD) process involving metastable He* atoms and He2* excimers which are populated by elastic and inelastic scattering of photoelectrons in the nanodroplets as well as by electron-ion recombination. This type of indirect ICD, observed in large He nanodroplets in nearly the entire XUV range, turns out to be more efficient than Li dopant ionization by ICD following direct resonant photoexcitation at hν = 21.6 eV and by charge-transfer ionization. Indirect ICD processes induced by scattering of photoelectrons likely play an important role in other condensed phase systems exposed to ionizing radiation as well, including biological matter.
Enhanced photocatalytic properties of Ge-doped Ga2O3 nanostructures synthesized via hydrothermal method
Authors: Kim Sunjae , Ryou Heejoong , Kim Hyoung Woo , Hwang Wan Sik 
Published: January 2025

Abstract
Ge-doped (1.4 at. %) β-Ga2O3 nanostructures are successfully synthesized using the hydrothermal method followed by annealing at 1000°C in an O₂ atmosphere. The crystal structures and morphologies of both intrinsic and Ge-doped β-Ga2O3 nanostructures are analyzed using high-resolution X-ray diffraction (HR-XRD), field-emission scanning electron microscopy (FE-SEM), Transmission Electron Microscope (TEM), and energy dispersive spectroscopy (EDS). Photoluminescence (PL) measurements are also performed to investigate defect-related energy levels within the bandgap. The photocatalytic activity is evaluated through the degradation of methylene blue (MB) in an aqueous solution. Ge-based precipitates form when the Ge concentration exceeds 1.4 atomic percent in the β-Ga2O3 nanostructures. As with other dopants such as Sn, Al, and Cr, this controlled incorporation of Ge significantly enhances the photocatalytic properties and potentially improves the electronic and optical properties of Ga2O3-based devices.
Realization of a 2H–Si microneedle with an ultrafast growth rate of 6.7 × 104 Å·s-1
Authors: Mun Suhyun , Kim Kyoung Hwa , Park Seonwoo , Jeon Injun , Jeon Hunsoo , Lee Jae Hak , Yang Min , Shin Myeong-Cheol , Oh Jong-Min , Shin Weon Ho , Kim Minkyung , Koo Sang-Mo , Lee Won Jae , Cho Chae Ryong , Kang Ye Hwan , Ahn Hyung Soo 
Published: January 2025

Abstract
Nanomaterials have facilitated the development of innovative technologies in various industries. However, most research has been limited to nanoscale phenomena, and the effects of nanoscale phenomena on microscale crystal growth remain obscure. In this study, we demonstrated a straight 2H-Si microneedle with a longitudinal growth rate of 6.7 × 104 Å·s-1, which could not be explained by conventional crystal growth mechanisms, through AlN nanowires. The AlN nanowires were grown using the hydride vapor-phase epitaxy method, which induced the formation of Al membranes when NH3 supply was ceased. At this time, an elliptical Al membrane was created within 0.166 s, in accordance with the principle of Plateau–Rayleigh instability. The average spacing of the Al membrane was 4 μm, and approximately 10,000 elliptical Al membranes absorbed SiCl almost simultaneously to form a 40-mm 2H-Si microneedle within 100 min of growth time. Therefore, we realized straight 2H–Si microneedles with a growth rate of 6.7 × 104 Å·s-1. Differing from the conventional growth mechanism, this new growth method sheds light on the mechanism by which nanoscale phenomena contribute to the growth of microscale crystals.
First-Principles Study on the Physical Properties of Al-based Wide Bandgap Perovskites Cs3AlIxBr6-x for Optoelectronic Applications
Authors: Ahmed Hussain , Mukhtar Surayya , Agathopoulos Simeon 
Published: January 2025

Abstract
This study aims at exploring the potential of inorganic wide-bandgap mixed-halide aluminum-containing perovskites of Cs3AlIxBr6-x in solar harvesting, by investigating their structural, electronic, and optical properties with density functional theory (DFT) using the APW+lo method. The structural properties were calculated with the PBE-GGA potential. Volume optimization and negative formation energies confirm the structural and thermal stability of the compounds. The electronic and optical properties were calculated using TB-mBJ potential. The TB-mBJ corrected bandgaps revealed that these materials belong to the wide bandgap (WBG) perovskites family, displaying bandgaps in the range of 3-5 eV. The electronic properties confirmed their direct bandgap nature with I-p and Br-p states mainly contribute to the formation of VB, and the Al-s, Al-p, and Cs-d states to CB. Absorption coefficients range from 10-140 x 104 per cm in the UV region thus making these WBG perovskites suitable for applications in this region. Optical properties show the absorption of light beyond 3 eV and validate the calculated electronic bandgaps. Absorption coefficients, optical conductivity, and dielectric function (real and imaginary) were calculated and revealed a peak shift from higher to lower energies with increasing I concentration. The above results suggest that these materials can be highly considered for use in photovoltaics (PVs), optoelectronic devices (LEDs, PDs), to power small batteries in IoT, in agrivoltaics, and in fabrication of semi-transparent solar cells.
Thermal effects on the resistive superconducting transition in step-edge YBCO squid arrays
Authors: de Andrade Marcio C , Maialle Marcelo Z. , Ferrante Nicholas B , Sundqvist Kyle M , Torikachvili Milton 
Published: January 2025

Abstract
The effect of thermal fluctuations in Yttrium Barium Copper Oxide (YBCO) SQUID filters (SQIFs), containing arrays of 258, 2304, and 4080 SQUIDs, were investigated using the electrical resistivity and applied magnetic ﬁeld up to 9 tesla. Our study reveals that the SQIFs experience a two-step superconductor transition. The transition at lower temperature is only present in the SQIF samples, not in the control sample without the SQFIs, and it is investigated here in terms of two primary dissipation mechanisms. The first dominates near the transition temperature and has the characteristics of thermally activated phase slippage (TAPS). At lower temperatures, the dominant characteristics are those of thermally-activated magnetic flux flow (TAFF). The mechanisms producing such behaviors contribute significantly to dissipation effects, resulting in an additional DC voltage that overlays the Josephson current, regardless of the quantity of SQUIDs in the SQIFs. These dissipation effects can have significant implications for technologies utilizing high-temperature superconductor SQIFs unless the operating temperature is lowered significantly below the superconducting transition temperature.&#xD;
Distinguishing Majorana bound states from Andreev bound states through differential conductance and current noise spectrum
Authors: Zhao Huajin , Wang Junrong , Mao Hong , Jin Jinshuang 
Published: January 2025

Abstract
We investigate the quantum transport through a quantum dot coupled with a superconducting&#xD;(SC) nanowire. By elaborating the differential conductance and current noise spectrum, we focus on the distinct characteristics&#xD;of the topological Majorana bound states (MBSs) and &#xD; trivial Andereev bound states (ABSs) hosted in SC wire.&#xD;For MBSs with a topological quality factor $q=1$,&#xD;we observe the degenerate features&#xD;manifested as the zero-bias peak (ZBP) &#xD;in differential conductance and the Rabi dips degeneracy (RDD) in noise spectrum.&#xD;In contrast, for ABSs with $q<1$,&#xD;the splitting of these degenerate features &#xD;depends on the linewidth, arising from realistic measurement conditions.&#xD; Furthermore, we identify the critical quality factors &#xD;$q_{\rm c}$ and $q_{\s}$ associated with the emergences of ZBP and&#xD; RDD, respectively.&#xD;The value of $q_{\rm c}$ is temperature-dependent, and we &#xD;establish a suitable temperature window to ensure the visibility of single ZBP in the experiments. &#xD;Whereas, $q_{\rm c}$ depends on the coupling strength rather temperature.&#xD;Typical values for these quality factors are&#xD;approximately $q_{\rm c}\approx 0.93$ and $q_{\s}\approx 0.99$.&#xD;Our results suggest that &#xD;the degenerate Rabi spectrum signal &#xD; could serve as a hallmark for the presence of MBSs, &#xD; which goes beyond the scope of differential&#xD;conductance.
NV center creation in diamond by local CW laser irradiation of shallow implantednitrogen
Authors: Enke Alexius , Raatz Nicole , Meijer J , Wunderlich Ralf 
Published: January 2025

Abstract
A novel creation procedure for the nitrogen-vacancy center in diamond is investigated. After shallow nitrogen implantation, a continuous-wave laser is used to induce NV formation, while simultaneously exciting fluorescence to enable live observation. Our investigations imply that a different mechanism than heat induced vacancy diffusion causes the formation of NV centers with this method and we suggest possible alternative pathways which could be responsible, based on the observed properties. Furthermore, we test the procedure for its capabilities for the controlled creation of single centers and show that the emergence of individual centers can be tracked, while achieving sub-micrometer spatial precision.
Indium Doping Effects on the Structural, Morphological and Electrical Properties of WO3 Powder Pellets
Authors: Khusayfan Najla M. , Khanfar Hazem K , Alharbi Seham R 
Published: January 2025

Abstract
Tungsten oxide powders were doped with indium at weight percentages ranging from 5 to 15 wt.% and pressed into pellet form under a pressure of 200 bars. The doping process was carried out using the solid-state reaction technique. The doped samples were sintered at 750 °C for 12 hours. Both undoped and indium-doped powder pellets exhibited a triclinic structure, with hexagonal InxWO3 emerging as a minor phase that increased with higher indium content. Indium doping increased microstrain, the percentage of stacking faults, and defect concentration while decreasing the crystallite sizes in the WO3 powder pellets. Morphological analysis of the samples revealed irregular grain shapes and sizes within the pellets. Notably, indium doping significantly reduced the porosity of WO3 from 7.42% to 3.83% as the indium content increased to 15 wt.%. Electrically, the n-type resistivity increased with higher doping levels, indicating deeper donor levels. Specifically, the donor states in the powder pellets increased from 0.21 eV to 0.27 eV as the indium content rose from 5 wt.% to 10 wt.%, and further reached 0.29 eV at 15 wt.% indium. Moreover, AC signal analysis of the powder pellets demonstrated their potential as microwave resonators suitable for antenna applications. Indium doping effectively engineered the maximum cutoff frequency, with values reaching 80 GHz in WO3 pellets doped with 15 wt.% indium. These powder pellets, with thicknesses not exceeding 700 μm and electrode areas of 3.14×10⁻² cm², show great promise for 5G/6G technology applications as concurrent quad-band antennas.
Exploring the impact of substituents on the photophysical properties of boron dipyrromethene dyes for enhanced photovoltaic performance
Authors: Cui Peng , Ling Zichao 
Published: January 2025

Abstract
Boron dipyrromethene (BODIPY) dyes are known for their strong fluorescence and excellent photostability, making them vital for various photoelectric applications. This study explores how different substituents affect the photophysical properties of BODIPY dyes to improve their performance in dye-sensitized solar cells (DSSCs). We examine six distinct BODIPY dye structures with unique electron-withdrawing (NO₂, CHO, Br) and electron-donating (OCH₃, NPh₂) substituents, along with a hydrogen-substituted variant, and report key photovoltaic parameters, including open-circuit voltage (Vₒc), short-circuit current density (Jₛc), fill factor (FF), and energy conversion efficiency (Ω). Using density functional theory (DFT) and time-dependent DFT (TD-DFT), we analyze the dyes' light-harvesting efficiency, electron injection efficiency, and overall energy conversion efficiency. Our results indicate that electron-donating groups, especially NPh₂ and OCH₃, significantly enhance Voc, Jsc, FF, and Ω, leading to improved energy conversion efficiencies. In contrast, while electron-withdrawing substituents increase chemical stability, they typically result in lower photovoltaic performance. This research underscores the importance of strategic substituent selection in optimizing BODIPY dyes for enhanced photoelectric performance, offering valuable insights for designing efficient photovoltaic materials.&#xD;
A new thermoelectric ECG model: Influence of bundle branch block and variations in body temperature
Authors: Ines Pascaline DONGMO VOUGMO , Djoumessi R T , Pelap Francois B , FOGUE Médard 
Published: January 2025

Abstract
The present work proposes a novel 2D thermoelectric model to investigate the behavior of specific pathological situation, such as bundle branch block. This model incorporates the heart, lungs, torso, and blood cavities. The dynamics of this system are governed by the Fitzhugh-Nagumo equations that simulate the electrical activity of cardiac myocytes coupled with temperature equations. Then, the parameters of the bundle branch block are considered to analyze their impact on the electrocardiogram. As results, we establish that the presence of bundle branch block significantly affects electrocardiogram morphology, leading to changes in wave amplitude and interval durations. Moreover, our results reveal that variations in body temperature deteriorate this pathological state, leading to further distortions of the electrocardiogram. These results clearly show that our thermoelectric model provides valuable insights into the behavior of bundle branch block under temperature variations. This knowledge could contribute to the development of new treatment and management strategies using thermal control to improve outcomes for patients with similar symptoms.&#xD;
Determining oscillator strengths of cesium from magic wavelengths of the D1 line
Authors: LIU Yang , FAN Shaofeng , LIU Wenyuan , LI Yijun , Bai Jiandong 
Published: January 2025

Abstract
A magic-wavelength optical dipole trap (ODT) can eliminate the differential light shift of transition between atomic states, so that the transition frequency between the two states is the same as that in free space, which is of great significance for exploring atomic structure. Here we calculate the dynamic polarizabilities of the 6S1/2 ground state and the 6P1/2 excited state of the cesium atom which are connected by the D1 line, by using the relativistic coupled cluster method, and obtain magic wavelengths of ODT laser for trapping the two states simultaneously. By using these magic wavelengths, we calculate oscillator strengths of the 6P1/2 → 7D3/2 transition for linearly and circularly polarized lights. Furthermore, we analyze the influence of magic wavelengths on oscillator strengths.
Microstructure, microhardness and wear properties Investigation in Friction Stir Processing of Stir Cast Mg/B4C metal matrix composite
Authors: Singh Amandeep , Singh Palwinder , Singh Amardeep , Ram Baljinder , Bala Niraj 
Published: January 2025

Abstract
Friction Stir Processing (FSP) has emerged as an excellent processing approach to tailor the microstructural and other properties of cast alloys and composite materials. In the current investigation, a stir-cast magnesium metal matrix composite (MMMC) reinforced with 12 wt% B4C particles was processed using single-pass FSP. FSP was carried out with a simple cylindrical tool pin using different tool rotational speeds of 800, 1000, 1200 rpm and transverse speed of 60 mm/min. Severe deformation occurred during FSP which helped to refine the distribution of the B4C particles and grain refinement of as-cast composites. Microstructural examination showed an appreciable grain refinement from 98 to 5μm because of dynamic recrystallization during FSP. The maximum microhardness of the friction stir processed (FSPed) composites increased from 73 Hv to 105.4 Hv. Pin-on-disk wear tests were conducted under dry sliding conditions in the load range of 1 kg to 5 kg at a 1 m/s sliding velocity. The wear results indicated an enhancement of wear properties of FSPed composites in comparison to as-cast magnesium metal matrix composites. The improved hardness and wear resistance results were pertaining to the remarkable refinement in grain size coupled with refined B4C particulates and uniform distribution. The best results for hardness and wear resistance of the FSPed composite were obtained for a sample processed at a tool rotation speed of 1000 rpm. SEM/EDS of the worn samples was carried out. The wear mechanism was found as slight abrasion and oxidation. After single pass FSP, the surface of Mg/12wt% B4C cast composite showed remarkable changes in worn surface morphology.
Quantitative Assessment of Delivered Dose in Carbon Ion Spatially Fractionated Radiotherapy (C-SFRT) and Biological Response to C-SFRT
Authors: Tsubouchi Toshiro , Umemura Misato , Minami Kazumasa , Hamatani Noriaki , Saruwatari Naoto , Takashina Masaaki , Yagi Masashi , Furutani Keith M , Shimizu Shinichi , Kanai Tatsuaki 
Published: January 2025

Abstract
Objective&#xD;Applying carbon ion beams, which have high linear energy transfer and low scatter within the human body, to Spatially Fractionated Radiation Therapy (SFRT) could benefit the treatment of deep-seated or radioresistant tumors. This study aims to simulate the dose distributions of spatially fractionated beams (SFB) to accurately determine the delivered dose and model the cell survival rate following SFB irradiation.&#xD;Approach&#xD;Dose distributions of carbon ion beams are calculated using the Triple Gaussian Model. The sensitive volume of the detector used in measurements was also considered. If the measurements and simulations show good agreement, the dose distribution and absolute dose delivered by SFB can be accurately estimated. Three types of dose distributions were delivered to human salivary gland cells (HSGc-C5): uniform dose distribution (UDD), and one-dimensional (1D) grid-like dose distributions (GDD) with 6 mm and 8 mm spacing. These provided high (Peak-to-Valley Dose Ratio, PVDR=4.0) and low (PVDR=1.64) dose differences between peak and valley doses, respectively. Linear-Quadratic (LQ) model parameters for HSGc-C5 were derived from the UDD and cell survival fractions (SF) were simulated for 1D GDD using these values.&#xD;Main results&#xD;Good agreement was observed between measurements and simulations when accounting for detector volume. However, the TPS results overestimated dose in steep gradient region, likely due to the 2.0 mm calculation grid size. LQ parameters for HSGc-C5 were α = 0.34 and β = 0.057. The 1D GDD with 6 mm spacing showed good agreement between simulations and experiments, but the 8.0 mm spacing resulted in lower experimental cell survival.&#xD;Significance&#xD;We successfully simulated grid-like dose distributions and conducted SF simulations. The results suggest potential cell-killing effects due to high-dose differences in SFB.&#xD;
Automated Classification of Cardiac Arrhythmia using Short-Duration ECG Signals and Machine Learning
Authors: Biswakarma Amar Bahadur , Rahul Jagdeep , KURMENDRA KURMENDRA 
Published: January 2025

Abstract
Accurate detection of cardiac arrhythmias is crucial for preventing premature deaths. The current study employs a dual-stage Discrete Wavelet Transform (DWT) and a median filter to eliminate noise from ECG signals. Subsequently, ECG signals are segmented, and QRS regions are extracted for further preprocessing. The study considers five cardiac arrhythmias: normal beats, Premature Ventricular Contractions (PVC), Premature Atrial Contractions (PAC), Right Bundle Branch Block (R-BBB), and Left Bundle Branch Block (L-BBB) for classification. Nine distinct temporal features are extracted from the segmented QRS complex. These features are then applied to six different classifiers for arrhythmia classification. The classifiers' performance is evaluated using the MIT-BIH Arrhythmia Database (MIT-BIH AD). Support Vector Machine (SVM) and Ensemble Tree classifiers demonstrate superior performance in classifying the five different classes. Particularly, the Support Vector Machine classifier achieves high sensitivity (97.44%), specificity (99.36%), positive predictive value (97.44%), and accuracy (98.97%) with a Gaussian kernel. This comprehensive approach, integrating preprocessing, and feature extraction, holds promise for improving automatic cardiac arrhythmia classification in clinical trials.
Unbinding of Alpha Chain of Hemoglobin in Sickle and Normal Structures
Authors: Powrel Jhulan , Koirala Rajendra Prasad , Adhikari Narayan P. 
Published: January 2025

Abstract
Sickle cell disease, a genetic disorder, is caused by a mutation of glutamic acid into valine in the β chain of hemoglobin at the sixth residue, resulting in structural change of the entire hemoglobin molecule into a sickle shape. We investigated the atomic level interaction between the α chain (chain A) and the remaining three chains to identify the structural modification in sickle hemoglobin using the molecular dynamics simulations. H-bond, solvent accessible surface area (SASA), hydrophobic interactions, salt bridges of sickle and normal hemoglobin have been estimated. The estimated parameters from sickle hemoglobin are compared to normal hemoglobin structure. Steered molecular dynamics (SMD) is utilized to estimate the force required in breaking hydrogen bonds in given chains. The SMD simulations at different pulling velocities show that the decoupling forces depend on values of pulling force. This relation is linear, 6780 pN to 12345 pN with pulling velocities of 0.00020 nm/ps to 0.00040 nm/ps in sickle hemoglobin. Much higher force of 8738 pN to 16557 pN in normal is required in normal hemoglobin with same spring constants values from k = 500 to 1100 kcal mol-1 nm-2 and same pulling velocities.
Unravelling the mechanism of transient coastal upwelling in the southeastern Arabian Sea triggered by Cyclone Michaung
Authors: Dev Rahul , KR Muraleedharan , Gireeshkumar T R , Shivaprasad S , Baliarsingh Sanjiba Kumar , Jayaprakash Anjana , Balakrishnan Nair T M 
Published: January 2025

Abstract
This study investigates the impact of Cyclone Michaung on coastal dynamics and biological changes in the southeastern Arabian Sea (SEAS). Utilizing data from a moored autonomous buoy, the water quality nowcasting system (WQNS), and multi-satellite datasets, the research documents significant changes in sea surface temperature (SST), salinity, and dissolved oxygen (DO) concentrations were driven by cyclone-induced upwelling and downwelling processes in the SEAS. The findings revealed that the passage of Cyclone Michaung led to a transient coastal upwelling event along the southwest coast of India (SWCI), marked by a notable decrease in SST and DO and an increase in salinity and chlorophyll-a concentrations, indicating enhanced biological production. The wind stress strengthening and changing wind pattern, almost parallel to the coast, initiated this process through wind-induced Ekman pumping, which uplifted the biological activity in the region.&#xD;