bluuebunny/crossref_metadata_2025_split huggingface dataset:
Gaia DR3 reveals the complex dynamical evolution within star clusters
Authors: Viscasillas Vázquez C. , Magrini L. , Miret-Roig N. , Wright N. J. , Alves J. , Spina L. , Church R. P. , Tautvaišienė G. , Randich S. 
Published: July 2024

Context. Star clusters, composed of stars born from the same molecular cloud, serve as invaluable natural laboratories for understanding the fundamental processes governing stellar formation and evolution.
Aims. This study aims to investigate correlations between the Mean Interdistance ($ \bar{D_{\mathrm{i}}} $), Mean Closest Interdistance ($ \bar{D_{\mathrm{c}}} $) and Median Weighted Central Interdistance ($ \bar{D_{\mathrm{cc}}} $) with the age of star clusters, examining their evolutionary trends and assessing the robustness of these quantities as possible age indicators.
Methods. We selected a sample of open clusters in the solar region and with a representative number of members (e.g. well populated and without outliers). The interdistances are derived from the spatial distribution of member stars within a cluster. Their evolution over time allows us to use them as age indicators for star clusters.
Results. Our investigation reveals a high-significant correlation between the interdistances and cluster age. Considering the full sample of clusters between 7 and 9 kpc, the relationship is very broad. This is due to uncertainties in parallax, which increase with increasing distance. In particular, we must limit the sample to a maximum distance from the Sun of about 200 pc to avoid artificial effects on cluster shape and on the spatial distribution of their stars along the line of sight.
Conclusions. By conservatively restraining the distance to a maximum of ∼200 pc, we have established a relationship between the interdistances and the age of the clusters. In our sample, the relationship is mainly driven by the internal expansion of the clusters and is marginally affected by external perturbative effects. Such relation might enhance our comprehension of cluster dynamics and might be used to derive cluster dynamical ages.
Long-term relationships of ionospheric electron density with solar activity
Authors: Jakowski Norbert , Hoque Mohammed Mainul , Mielich Jens 
Published: July 2024

Greenhouse gases such as carbon dioxide and methane that are causing climate change may cause long-term trends in the thermosphere and ionosphere. The paper aims to contribute to exploring long-term effects in the ionosphere focusing on the impact of solar activity changes. Peak electron density data derived from vertical sounding measurements covering 65 years at the ionosonde stations Juliusruh (JR055), Boulder (BC840), and Kokubunji (TO536), have been utilized to estimate the long-term behavior of daytime ionospheric F2 layer ionization in relation to the solar 10.7 cm radio flux index F10.7. In parallel, Global Navigation Satellite System (GNSS) based vertical total electron content (TEC) data over the ionosonde stations in combination with the peak electron density data have been used to derive the equivalent slab thickness τ for estimating long-term behavior in the period 1996–2022. A new approach has been developed for deriving production and loss term proxies for studying long-term ionization effects from F2 layer peak electron density and TEC data. The derived coefficients allow for estimating the long-term variation of atomic oxygen and molecular nitrogen concentrations including their ratio during winter months. The noon-time slab thickness values over Juliusruh correlate well with the decrease of F10.7 and the F2 layer peak height and enable estimating the neutral gas temperature. The equivalent slab thickness decreases by about 20 km per decade in the period 1996–2022, indicating a thermospheric cooling of about 100 K per decade for Juliusruh. Whereas the oxygen concentration decreases, the loss term, considered as a proxy for molecular components of the neutral gas, in particular N2, increases with the long-term solar activity variation. Considering 11-year averages of the production and loss terms under wintertime conditions, the long-term study reveals for the O/N2 ratio a percentage decrease of 5% per decade and for F10.7 about 3.1% per decade in a linear approach referred to the year 1970. Linear models of 11 years averaged NmF2 and foF2 from corresponding F10.7 show a very close correlation with the temporal variation of F10.7 until about 1990. The root mean square errors are in the order of 1.0–1.3 · 1010 m−3 for NmF2 and 0.03–0.05 MHz for foF2. After 1990 the linear models deviate from F10.7 at all selected mid-latitude ionosonde stations indicating a non-local effect.
The Clinical Research on Ginger (Zingiber officinale): Insights from ClinicalTrials.gov analysis
Authors: Matin Maima , Matin Farhan Bin , Ksepka Natalia , Wysocki Kamil , Mickael Michel-Edwar , Wieczorek Marek , Horbańczuk Jarosław Olav , Jóźwik Artur , Atanasov Atanas G. 
Published: June 2024

AbstractGinger (Zingiber officinale) has a rich history of traditional medicinal use and has attracted a global interest in its health benefits. This study aims to provide insights into the clinical research landscape on ginger, focusing on its pharmacological effects and studied health-related outcomes. The study design involves systematic analysis of data from clinical trials available on ClinicalTrials.gov and discussion of findings in the context of the existing scientific knowledge. A comprehensive analysis of clinical trials registered on ClinicalTrials.gov related to ginger was first conducted, and the scientific background related to specific ginger clinical research avenues was further evaluated through PubMed searches. A variety of trial designs were identified, including treatment, prevention, and supportive care objectives. A total of 188 studies were identified on ClinicalTrials.gov, of which 89 met the inclusion criteria. Among the 89 trials, treatment
objectives were predominant (47.2%), and dietary supplements (40.4%) and drugs (27%) were the most prevalent intervention types. These trials covered various health outcomes, such as antiemetic activity, analgesic function, effects on health-related quality of life, blood pressure variation, energy expenditure, and reduction in xerostomia. This study analysis provides a comprehensive overview of the clinical trials landscape on ginger, focusing on its broad spectrum of potential health benefits. While individual trials show promising results, a significant gap in the available data with a low reporting rate of final results is identified, underscoring the need for further research to establish conclusive evidence of gingerʼs therapeutic potentials.
Homoeopathy for the Management of Delusional Disorder: A Case Report
Authors: Moorthi S. Karunakara , K.C Manu Chandran 
Published: July 2024

Abstract
Introduction Delusions, a core symptom of psychosis, are false beliefs that are rigidly held with strong conviction despite contradictory evidence. Persistent delusions if held for more than 1 month lead to the diagnosis of delusional disorder (DD) as per the Diagnostic and Statistical Manual of Mental Disorders-5. Very sparse literature is available evaluating the utility of individualised homoeopathic medicine in this condition.
Materials and Methods A 60-year-old man presenting with symptoms of DD was treated during the period of February 2020 to February 2021. Individualised homoeopathic medicine was prescribed. Outcomes were assessed using Psychotic Symptom Rating Scales. Modified Naranjo Criteria was used to assess whether the changes were likely to be associated with the homoeopathic intervention.
Results A beneficial result was obtained from Individualised homoeopathic treatment.
Conclusion Even though this is a single case report, the recovery of the patient from the suspiciousness is remarkable and there is no relapse of the symptoms. The patient's family life is peaceful now and he was able to rejoin his job.
Medium- and long-term outcomes of early childhood education: experiences from Turkish large-scale assessments
Authors: Suna H. Eren , Ozer Mahmut 
Published: June 2024

AbstractThe benefits of early childhood education (ECE) to children extend throughout their lives. A more equitable education system is also dependent upon the universalization of ECE, beyond its personal benefits. A limited number of studies have examined the relationship between ECE attendance and educational outcomes in Türkiye, despite its importance at both the educational and systemic levels. As part of this comparative study, we examined the relationship between ECE attendance and academic achievement in Türkiye over the medium and long term. We considered high stakes assessments for the transition to upper-secondary education (at the end of the eighth grade) and higher education (at the end of the 12th grade) within the scope of this study. Based on the official student recordings in Türkiye, ~5.6 million students were analyzed in the study. For the comparison of group means, partial-eta squares were used, and descriptive comparisons were made for the comparison of group rates. There was a stronger relationship between ECE attendance and medium-term achievement. As a result, students who attended an ECE program had significantly higher scores on the transition to upper-secondary education. Despite similar rates of transition, attendance had a higher rate of transition to formal bachelor programs, prestigious higher education programs, and students’ prioritized programs. ECE programs are particularly beneficial to students with low socio-economic status (SES) according to additional analyses. Medium- and long-term academic indicators are correlated with ECE attendance, with the medium-term relationship being particularly robust. This emphasizes the importance of recent investments in universalizing early childhood education in Türkiye. It is suggested that further research be conducted in order to control SES and other demographic variables.
Building an AI ecosystem in a small nation: lessons from Singapore’s journey to the forefront of AI
Authors: Khanal Shaleen , Zhang Hongzhou , Taeihagh Araz 
Published: July 2024

AbstractArtificial intelligence (AI) is arguably the most transformative technology of our time. While all nations would like to mobilize their resources to play an active role in AI development and utilization, only a few nations, such as the United States and China, have the resources and capacity to do so. If so, how can smaller or less resourceful countries navigate the technological terrain to emerge at the forefront of AI development? This research presents an in-depth analysis of Singapore’s journey in constructing a robust AI ecosystem amidst the prevailing global dominance of the United States and China. By examining the case of Singapore, we argue that by designing policies that address risks associated with AI development and implementation, smaller countries can create a vibrant AI ecosystem that encourages experimentation and early adoption of the technology. In addition, through Singapore’s case, we demonstrate the active role the government can play, not only as a policymaker but also as a steward to guide the rest of the economy towards the application of AI.
A novel means to generate high pressure
Authors: Pravica Michael , Cifligu Petrika , Sanchez Adrian Lua , Malik Trimaan , Appathurai Narayan , Moreno Beatriz Diaz 
Published: July 2024

Diamond anvil cells are the most popular means of generating pressures above 2 GPa. However, in many experiments, such as nuclear magnetic resonance and x-ray absorption, the metallic pressurizing gasket (which confines much of the sample) represents an occluding barrier that requires a low Z gasket material (e.g., Be), a split gasket, or other means to enable better coupling of the sample to electromagnetic radiation. In this paper, we demonstrate a novel method for generating high pressures that confines the sample just above the plane of the gasket by using a diamond with a laser hole drilled into the center of the tip. The sample is then confined by the hole, which is sealed by a flat gasket that fits over the hole. When load is applied to the diamonds, metal flows from the deformed gasket into the hole thereby pressurizing the sample similarly to how a piston pressurizes gas inside a cylinder. The pressurized sample is above the metallic gasket plane just inside the tip of the diamond, and thus easily accessible via x rays or visible light that skims just above the plane of the gasket providing an enhanced aperture of radiation collection. We have demonstrated the utility of this method by obtaining Raman spectra of SnC2O4 and x-ray diffraction spectra of seleno-DL-cystine, all at high pressures.
On the quantum dynamical treatment of surface vibrational modes for reactive scattering of H2 from Cu(111) at 925 K
Authors: Sah Mantu Kumar , Naskar Koushik , Adhikari Satrajit , Smits Bauke , Meyer Jörg , Somers Mark F. 
Published: July 2024

We construct the effective Hartree potential for H2 on Cu(111) as introduced in our earlier work [Dutta et al., J. Chem. Phys. 154, 104103 (2021), and Dutta et al., J. Chem. Phys. 157, 194112 (2022)] starting from the same gas–metal interaction potential obtained for 0 K. Unlike in that work, we now explicitly account for surface expansion at 925 K and investigate different models to describe the surface vibrational modes: (i) a cluster model yielding harmonic normal modes at 0 K and (ii) slab models resulting in phonons at 0 and 925 K according to the quasi-harmonic approximation—all consistently calculated at the density functional theory level with the same exchange–correlation potential. While performing dynamical calculations for the H2(v = 0, j = 0)–Cu(111) system employing Hartree potential constructed with 925 K phonons and surface temperature, (i) the calculated chemisorption probabilities are the highest compared to the other approaches over the energy domain and (ii) the threshold for the reaction probability is the lowest, in close agreement with the experiment. Although the survival probabilities (v′ = 0) depict the expected trend (lower in magnitude), the excitation probabilities (v′ = 1) display a higher magnitude since the 925 K phonons and surface temperature are more effective for the excitation process compared to the phonons/normal modes obtained from the other approaches investigated to describe the surface.
A standalone and portable imaging detection system with embedded computing for automated defect inspection of microfluidic devices
Authors: Yang Shuo , Feng Xin , Wang Qingzheng , Xu Fan , Fan Yiqiang 
Published: July 2024

Abstract
The existing methods for defect detection in PDMS microfluidic chips typically involve complex image recognition algorithms or manual inspection and still lack efficiency and reliability. Although some automatic defect detection methods have been proposed in recent years, most of them still rely on external computation systems to deploy. To address these challenges, we propose an independent portable defect detection system with embedded computing for microfluidic devices. This portable system is completely self-contained, integrating an image acquisition module, a control panel module, a power module, and an embedded computing control module to realize chip detection, processing, and result display functions. Experimental results show that the system can effectively detect most of the commonly seen defects in PDMS-based microfluidic chips, proving to be more efficient and reliable than manual inspection. With the control of the embedded system, two detection methods: template matching (based on comparison with standard samples) and automatic defect detection (based on surface defect recognition) were used to identify defects in PDMS-based microfluidic chips. The proposed system can automatically inspect and analyze chips without the need for external laboratory support and can provide a promising solution for future microfluidic chip manufacturing and operation.
Progress of GaN-based E-mode HEMTs
Authors: Huang Huolin , Lei Yun , Sun Nan 
Published: July 2024

Abstract
With the continuous improvement of the power density and operating frequency in power conversion systems, it is necessary to develop the new power electronic products with better performances than the conventional semiconductors. As a typical representative of the wide-bandgap semiconductors, gallium nitride (GaN)-based heterostructure has unique high-density two-dimensional electron gas (2DEG) and hence can be used to fabricate the fast high electron mobility transistors (HEMTs) with low power loss. Therefore, it is considered as a promising candidate for the next-generation power devices to improve the switching efficiency and speed. Compared with the depletion mode (D-mode, also known as normally-on) devices, the enhancement-mode (E-mode, also known as normally-off) devices have the advantages of safety, energy-saving, and better circuit topology design, making them more attractive for industry applications. In this paper, the different structure schemes and fabrication technologies of the GaN-based E-mode HEMTs are reviewed and summarized. Their technical characteristics are systematically compared. The influences of material epitaxial structure, ohmic contact, material etching, field plate design, and passivation process on the device performances are discussed in detail wherein the fabrication process of the recessed-gate MIS-HEMTs are emphatically illustrated, focusing on the interface treatment technology and dielectric engineering. In addition, the complicated reliability issues in the E-mode HEMTs induced by high temperature, high voltage, and high frequency switching and corresponding physical mechanisms are introduced and discussed. Finally, the potential technical solutions are proposed and the future application fields of GaN-based E-mode HEMTs are prospected.
Effect of hydrogen poisoning on p-gate AlGaN/GaN HEMTs
Authors: He Zhiyuan , He Liang , Jiang Kun , Duan Xiaoyue , Shi Yijun , Chen Xinghuan , Chen Yuan , Wu Hualong , Lu Guoguang , Ni Yiqiang 
Published: July 2024

Abstract
In this work, we investigate the degradation behavior and mechanism of p-gate AlGaN/GaN high-electron mobility transistors (HEMTs) for the first time under hydrogen (H2) atmosphere. The experimental results reveal significant decrease in drain-to-source current, negative drift in threshold voltage, increase in off-state gate leakage current, and deterioration of subthreshold swing in the p-gate AlGaN/GaN HEMT after H2 treatment. The degradation of the electrical parameters is considered to hydrogen poisoning phenomenon. Through secondary ion mass spectrometry and variable temperature photoluminescence spectroscopy, we observe the increase in hydrogen concentration in the p-GaN layer and the formation of electrically inactive Mg–H complexes after H2 treatment. As results, the effective hole concentration decreases and the trap density of the device increases, which are confirmed by Hall effect measurement and low-frequency noise analysis, respectively. The detrimental effect of hydrogen on p-gate AlGaN/GaN HEMTs can be attributed primarily to the compensation of Mg doping and the generation of defects.
An effective method for improving GNSS precise point positioning performance at the day boundary
Authors: Xiao Jingxin , Li Haojun , Sun Yafeng , Liu Xiaolu 
Published: July 2024

Abstract
Aiming to address poor self-consistency of the satellite clock and orbit interpolations at the day boundary, which is caused by the discontinuities of their International GNSS Service (IGS) products for two consecutive days, an effective method is proposed to improve the precise point positioning (PPP) performances at the day boundary. According to different orders of Lagrange interpolator and different IGS Analysis Centers products of Center for Orbit Determination in Europe (CODE), GeoForschungsZentrum (GFZ) and Wuhan University (WUH), biases at the day boundaries are estimated and analyzed using a 4 day (DOY 94-97, 2022) data set of GPS, BDS-3 and Galileo from 123 IGS stations. These estimated biases show the time-varying characteristics. The differences in biases across 9th-11th orders of Lagrange interpolator are minimal, and these variances have a negligible impact on positioning. The results show that this poor self-consistency at the day boundary has an obvious influence on the kinematic PPP positioning, especially there is a centimeter-level variation at time of 24:00:00/00:00:00. This influence on the Up direction of kinematic PPP positioning is more serious than other directions. When the bias is estimated and corrected, the kinematic PPP positioning accuracies at the day boundary have a mean improvement of 0.043, 0.064 and 0.027 m for WUH, GFZ and CODE, respectively. The mean improvements for GPS, BDS-3 and Galileo are 0.021, 0.062 and 0.051 m. Additionally, the static PPP performances at the day boundary show the convergence times are shortened by 3.2, 6.2, and 2.5 min for WUH, GFZ and CODE, respectively, when the poor self-consistency of the satellite clock and orbit interpolations is estimated and corrected. Meanwhile, its 0.5 and 1 h positioning accuracies are improved.
Multi-rolling element faults diagnosis of rolling bearing based on time-frequency analysis and multi-curves extraction
Authors: Liu Xiru , Yan Changfeng , Lv Ming , Li Shengqiang , Wu Lixiao 
Published: July 2024

Abstract
In industrial production, rolling bearings are widely used as key mechanical components in all types of rotating machinery. Fault diagnosis is essential for predicting bearing damage in advance, avoiding sudden equipment downtime and reducing economic losses. However, rolling element fault diagnosis of rolling bearings continues to be a challenge, especially with multi-rolling element faults. In view of the characteristics of randomness, weakness, and coupling in the vibration signal generated by multi-rolling element faults in rolling bearings, a multi-rolling element fault detection method is proposed by combination time-frequency (TF) analysis with multi-curves extraction methods. The pre-processing method combined autoregressive model with maximum correlated kurtosis deconvolution is employed to enhance the weak periodic fault impulses in the raw vibration signals of the rolling bearing. Then an improved dynamic path multi-curves extraction method is proposed to extract multiple TF curves from the TF spectrogram (TFS) constructed via short-time Fourier transform. According to the proposed classification criteria, the TF curves are classified as homologous faults. The TF masking (TFM) method is employed to keep TF information closely associated with the fault impulse. Finally, the fault signals are reconstructed sequentially based on the TFS processed by TFM, and precise identification of multi-rolling element faults is achieved by envelope analysis. Experimental results demonstrate the effectiveness of the proposed method in extracting the weak fault features of multi-rolling elements and accomplishing fault separation and diagnosis.