bluuebunny/crossref_metadata_2025_split huggingface dataset:
Evaluation of large‐scale cycling environment by using the trajectory data of dockless shared bicycles: A data‐driven approach
Authors: Ni Ying , Wang Shihan , Chen Jiaqi , Feng Bufan , Yu Rongjie , Cai Yilin 
Published: September 2024

AbstractCycling is increasingly promoted worldwide, but many urban areas lack satisfactory cycling environments. Assessing these environments is crucial, but existing methods face data challenges for large urban networks. This study proposes a data‐driven framework using dockless shared bicycle data to efficiently evaluate large‐scale cycling environments. First, critical cycling behaviour features that reflect cyclists’ perceptions are identified applying the fuzzy C‐means and random forest model. Then, a distribution‐oriented evaluation method is developed, ensuring the incorporation of cyclist heterogeneity and quantifying the quality differences among road segments by combining statistical analysis with a hierarchical clustering model. The evaluation framework is applied to Yangpu District, Shanghai, using Mobike data covering 114.9 km of cycling roads. Results show that indicators related to speed magnitude and fluctuation are critical, and an experimental study validates the effectiveness of the data‐driven feature extraction method. A minimum trajectory sample size of 260 is required to account for cyclist heterogeneity for one road segment to be evaluated. Further analysis of lower‐performing segments identifies vehicle‐bicycle separation, on‐street parking, and traffic volume as key influencing factors. The rationality of these findings further supports the reliability of the evaluation framework.
A background-estimation technique for the detection of extended gamma-ray structures with IACTs
Authors: Wach T. , Mitchell A. , Mohrmann L. 
Published: September 2024

Context. Estimation of the number of cosmic-ray-induced background events is a challenging task for Imaging Atmospheric Cherenkov Telescopes (IACTs). Most approaches rely on a model of the background signal derived from archival observations, which is then normalised to the region of interest (ROI) and respective observation conditions using emission-free regions in the observation. However, this is disadvantageous for the analysis of large, extended γ-ray structures, where no sufficient source-free region can be found.
Aims. We aim to address this issue by estimating the normalisation of a three-dimensional background model template from separate, matched observations of emission-free sky regions. As a result, the need for an emission-free region in the field of view of the observation becomes unnecessary.
Methods. To this end, we implemented an algorithm to identify observation pairs with the most closely matching observation conditions. We used the open-source analysis package Gammapy to estimate the background rate, facilitating seamless adaptation of the framework to many γ-ray detection facilities. We employed public data from the High Energy Stereoscopic System (H.E.S.S.) to validate this methodology.
Results. The analysis demonstrates that employing a background rate estimated through this run-matching approach yields results consistent with those obtained using the standard application of the background model template. Furthermore, we confirm the compatibility of the source parameters obtained through this approach with previous publications, and present an analysis employing the background model template approach, along with an estimation of the statistical and systematic uncertainties introduced by this method.
Determination of metallicities of red giant stars using machine learning techniques applied to the narrow and broadband photometry of the S-PLUS survey
Authors: Molina-Jorquera F. , Damke G. , Fernández-Olivares D. , Jaque-Arancibia M. , Almeida-Fernandes F. , Daflon S. , Schoenell W. , Ribeiro T. , Kanaan A. , Torres-Flores S. , de Oliveira C. Mendes 
Published: September 2024

Aims. The aim of this study is to obtain metallicities of red giant stars from the Southern Photometric Local Universe Survey (S-PLUS) and to classify giant and dwarf stars using artificial neural networks applied to the S-PLUS photometry.
Methods. We combined the five broadband and seven narrow-band filters of S-PLUS – especially centred on prominent stellar spectral features – to train machine learning algorithms. The training catalogue was made by cross-matching the S-PLUS and Apache Point Observatory Galactic Evolution Experiment 2 (APOGEE-2) survey catalogues. The classification neural network uses the colours (J0378 - u), (J0395 - g), (J0410 - g), (J0515 - g), (J0660 - r), (g - z) and (r - i) as input features, whereas the network for metallicities uses the colours (J0378 - u), (J0395 - g), (J0410 - g), (J0515 - g), (J0660 - r), (u - g) and (r - z) as input features.
Results. The resulting network is capable of identifying ~99% of the giants in the test set. The network for determining the photometric metallicities of giant stars estimates metallicities in the test set a with a standard deviation of σgiants ~ 0.07 dex with respect to the spectroscopic values. Finally, we used the trained artificial neural networks to generate a publicly available catalogue of 523 426 stars classified as red giant stars from S-PLUS, which we used to explore metallicity gradients in the Milky Way.
Conservative versus surgical therapy for idiopathic and secondary megacolon or megarectum in adults – a retrospective multicentre controlled study
Authors: Schmitz Daniel , Meier Emilia , Axt Steffen , Arlt Gerrit , Kienle Peter , Johannink Jonas , Königsrainer Alfred , Mohammad Owais , Jakobs Ralf , Willis Stefan , Demir Ihsan Ekin , Friess Helmut , Hetjens Svetlana , Ebert Matthias Philip , Reissfelder Christoph , Vassilev Georgi 
Published: September 2024

Abstract
Background Idiopathic and secondary megacolon (MC) and megarectum (MR) in adults is associated with persistent bowel dilatation and reduced intestinal motility. Little is known about the optimal treatment of this rare disease. Therefore, we retrospectively analysed long-term data from these patients in 5 community and university hospitals, focusing on conservative versus surgical treatment.
Methods Patient records from 7/2004 to 9/2021 were screened for colorectal diseases with severe constipation and persistent megacolon ≥ 9.0 cm and/or megarectum ≥ 6.5 cm. Follow up-data was collected through telephone interviews and written surveys. ClinicalTrialsgov NCT04340856.
Results Sixty-seven patients with idiopathic (n=10) and secondary (n=57) MC or MR were identified with only 20 of 67 patients (29.9%) correctly diagnosed. Mean/median age was 64/69 (range 18–93) years. Thirty-two patients were treated with laxative regimens, and 35 underwent surgery (colostomy: n=12, segmental resection, or hemicolectomy: n=10, (sub)total colectomy: n= 13) after conservative treatment attempts in 32/35 (91.4%). The mean/median follow-up was 4.2/2.7 (range 0.1–17.0) years. The readmission rate for MC-associated symptoms was significantly higher after conservative treatment than after surgical therapy at 12 (0.84 vs. 0.36 per patient, p=0.036), 24 (1.00 vs. 0.52, p=0.048) and 36 (1.13 vs. 0.58, p=0.047) months, as was the number of patients with persistent laxative dependence (28/32 (87.5%) vs. 19/33 (57.6%); p = 0.007). Therapy-associated adverse events (Clavien-Dindo classification) were documented more often in surgically treated patients (11/35, 31.4%) (p=0.025).
Conclusion Surgical treatment may be considered earlier if idiopathic or secondary MC or MR is correctly diagnosed, and conservative treatment has been attempted.
Innovative Orbital Periosteum Suturing Technique for Endoscopic Medial Orbital Wall Reconstruction
Authors: Takeda Teppei , Hardison Scott , Omura Kazuhiro , Ishii Yudo , Mori Ryosuke , Kimple Adam J. , Senior Brent A. , Otori Nobuyoshi , Klatt-Cromwell Christine , Thorp Brian D. 
Published: September 2024

Abstract
Background Advances in endoscopic orbital surgery have sparked discussion regarding reconstructive procedures for medial orbital wall defects following tumor removal. This study describes an innovative orbital periosteal suturing technique that addresses the functional and aesthetic concerns created by orbital surgery.
Objective Comprehensive clinical evaluation of a novel orbital periosteal suturing technique for endoscopic medial orbital wall reconstruction.
Methods A retrospective chart review identified five patients who underwent endoscopic transnasal resection and subsequent orbital periosteal suturing for reconstruction. The surgical approach involved a binostril transseptal technique to create a broad surgical corridor. The postoperative follow-up was 13.4 ± 1.8 months.
Results In the five patients, the mean age was 47.6 ± 13.0 years and the lesions were predominantly distributed on the left side (60%). Reconstruction time with the orbital periosteal suture procedure averaged 47.2 ± 6.6 minutes, employing four to five stitches. No patients experienced short-term complications such as visual acuity defect, new or exacerbated diplopia, or cranial nerve palsy within 2 weeks, and no long-term complications such as enophthalmos or prolonged diplopia were observed.
Conclusion Orbital periosteal suturing is an effective and resource-efficient technique for endoscopic reconstruction of the medial orbital wall. Surgeons may consider this method among the available options for orbital reconstruction, representing a novel advancement in the field.
Practical Multigram Approach to Conformationally Constrained α-Proline-Based Building Blocks with γ-Spiro Conjunction
Authors: Volochnyuk Dmytro M. , Ryabukhin Serhiy V. , Iermolenko Ievgenii A. , Kolosov Oleksii S. , Ostapchuk Eugeniy N. , Lega Dmitry A. , Derkach Nikita O. , Levchenko Kostiantyn V. , Makhankova Valeriya G. , Rozhenko Alexandr B. 
Published: September 2024

AbstractUnusual amino acids have arisen as an indispensable instrument at the disposal of modern medicinal chemistry. While extensively exploited as building blocks in the search for new pharmaceuticals, their application goes far beyond. They are currently involved in explorations of the structure and conformational mobility of peptides, modification and amplification of peptidomimetic activity, and others. Herein, we report an effective synthetic approach to nonplanar, conformationally restricted, sp3-enriched spirocyclic α-prolines. The protocol employs readily available nitrile-based starting materials and conventional experimental procedures. The synthetic sequence is concise and includes three principal stages (one of them a four-step telescopic process). The reactions proceed on a multigram scale affording the target prolines in overall good yields. The possibility of chiral separation of the synthesized racemic spiro prolines to both pure enantiomers is shown. The building blocks synthesized in the study are expected to have practical uses in the field of medicinal chemistry.
Rapid Whole-Genome Sequencing in Acutely Ill Children: A Single Pediatric Center Experience
Authors: Totapally Balagangadhar R. , Jayakar Parul , Diaz-Barbosa Magaly , Sasaki Jun , Jayakar Anuj , Sendi Prithvi , Soler Diana , Janvier Michelin , Espinal Paula , Gupta Apeksha , Salyakina Daria 
Published: September 2024

AbstractThe aim of this study was to describe the turnaround time, diagnostic yield, and clinical impact of rapid whole-genomic sequencing (rWGS). We conducted a prospective observational study in acutely ill children (0–21 years) with an undiagnosed, potentially genetic abnormality in a children's hospital. A phenotype-prioritized analysis approach for rWGS was utilized. The turnaround times, diagnostic yield, number of genes detected, inheritance pattern, zygosity, and the clinical impact of positive or negative tests were analyzed. Out of a total of 109 children, 92 abnormal (pathogenic or likely pathogenic) gene variants were detected in 60 (55%) patients. There were 45 neonates, 35 infants, and 29 children. The admission location was 49.5, 34.9, and 15.6% in the pediatric intensive care unit (PICU), neonatal intensive care unit (NICU), and cardiac intensive care unit (CICU), respectively. The median (interquartile range [IQR]) times for the return of preliminary and final results were 3 (2–5) and 10 (6–14) days, respectively. With ultra-rapid processing, the median time to final results was shorter (5 [3–7] vs. 12 [7.75–15] days). Neurologic issues were the most common underlying admission diagnoses. The diagnostic yield for a causative gene was 47.7%. The diagnostic yield was not different based on age group or location of admission but higher in metabolic issues (78.6 vs. 43.2%; odds ratio [OR]: 4.8; 95% confidence interval [CI]: 1.3–18.4). There was a change in clinical management in 39.4%. In acutely ill children with undiagnosed conditions and with clinical suspicion of a genetic disorder, rWGS detected gene variants in 55% with a diagnostic yield of 47.7% and resulted in a change in the management in 39.4%. The diagnostic yield in patients with metabolic conditions was the highest.
Atomistic simulation study of Li5GaO4 for lithium-ion batteries
Authors: Mathushan Sathiyamoorthy , Abiman Poobalasingam , Iyngaran Poobalasuntharam , Kuganathan Navaratnarajah 
Published: September 2024

The advancement of rechargeable batteries for electronic devices requires continuous development of innovative materials for anodes, cathodes, and electrolytes. Li5GaO4 stands out as a promising electrode material for lithium-ion batteries, demonstrating swift Li-ion conductivity. Employing sophisticated computational simulation techniques based on classical potentials, we investigate the defect, diffusion, and dopant characteristics of Li5GaO4. Our simulations reveal that the Li Frenkel defect process possesses a minimum energy of 1.00 eV, while the Li–Ga anti-site isolated defect exhibits a higher energy. The Li–Ga anti-site cluster defect is favored over the Li–Ga anti-site isolated defect due to an exothermic binding of isolated defects forming a cluster (−2.28 eV). The projected long-range Li diffusion pathway aligns along the c-axis, featuring an activation energy of 0.42 eV. Notably, Na and Al emerge as the most promising isovalent dopants for the Li and Ge sites, respectively, with solution energies of −0.92 and 3.62 eV. Furthermore, the introduction of Si doping at the Ga site facilitates the formation of Li vacancies. This study offers crucial insights into the design of advanced materials, improving the capacity and performance of lithium-ion batteries, particularly addressing challenges associated with liquid electrolytes by utilizing solid electrolytes.
A magnetic diagnostic suite for the Pegasus-III experiment
Authors: Reusch J. A. , Aslin M. W. , Bongard M. W. , Diem S. J. , Goetz J. A. , Nornberg M. D. , Rajendra A. S. , Redd S. , Rodriguez Sanchez C. , Sassella R. K. , Sontag A. C. , Weberski J. D. , Winz G. R. 
Published: September 2024

Pegasus-III is an ultralow aspect ratio spherical tokamak providing a dedicated US experiment for comparative solenoid-free startup studies. A new magnetic diagnostic suite for equilibrium and low frequency (&lt;200 kHz) magnetohydrodynamic mode analysis has been installed. These new diagnostics address the significant challenges of measuring magnetic field in a high noise environment with the majority constrained to fit in an 8 mm diagnostic gap on the high field side. Electrostatic switching noise generated by the 16 independent current feedback-controlled power supplies produces dVcm/dt ∼ 1 kV/μs and volt level common mode noise on the magnetics. Immunity to this switching noise is accomplished through differential signal runs and signal processing, along with end-to-end electromagnetic interference shielding. The magnetic measurements are simultaneously digitized at 1 MHz and conditioned by precision 8 pole Butterworth filters with a corner frequency of 200 kHz to prevent aliasing down to the 16-bit level over the full passband. Ex-vessel calibrations of the Bp coils were completed with a typical uncertainty of &lt;0.5%. Stray toroidal field pickup from coil misalignment or positioning errors is corrected using a physics-based model. Comparisons of the corrected measurements to modeling agree to within 1.3% on average. This is within the 1.5% measurement uncertainty that a sensitivity analysis determined is needed for accurate fast boundary and equilibrium reconstruction.
Enhanced inertia friction welding of aluminum alloy and high-strength steel using CrCoNi interlayer: Microstructural and mechanical characterization
Authors: Jiang Qiming , Wu Wei , Yang Hongrui , Li Kunhang , Zhang Guangchuan , Huang Hong 
Published: September 2024

The significant disparities in physical and chemical properties between aluminum alloy and high-strength steel pose substantial challenges for conventional friction joining techniques. To address this issue, this study proposes a novel approach utilizing inertial friction welding with an interlayer to join these dissimilar materials. A CrCoNi medium entropy alloy sheet was selected as the interlayer due to its intermediate melting point, thermal conductivity, strength, and surface hardness between 6061-T6 aluminum alloy and 42CrMo steel, as well as its high element mixing entropy. These properties were deemed crucial for balancing interface heat generation and regulation the formation of intermetallic compounds. The experimental procedure involved embedding the CrCoNi sheet into the end face of the 6061-T6 aluminum alloy, followed by the application of IFW to join the aluminum alloy with 42CrMo high-strength steel. This investigation focuses on examining the effects of three distinct friction speeds (3800, 4000, and 4200 rpm) on the microstructural characteristics and mechanical properties of the regulating joints with the CrCoNi interlayer. Results demonstrate that the CrCoNi enhances the temperature at the steel-side interface through friction with 42CrMo steel and 6061-T6 aluminum, combined with adjustments in the friction sequence and duration, promoting plastic deformation. The axial transfer of heat creates a temperature gradient at the joint, enabling low-temperature welding on the aluminum side and forming a mechanical interlocking structure at the interface. The diffusion of Cr, Co, and Ni elements regulates the type and thickness of interfacial intermetallic compounds, ultimately enhancing the joint's strength. The thickness of the intermetallic compounds AlNi3, FeAl3, AlCo, and Fe2Al5 formed at the interface is less than 2 µm. A phase transformation occurred at the 42CrMo high-strength steel interface, leading to the formation of numerous needle-like martensites, which increased the Vickers hardness in the welding seam to 763.9 HV. The joint's tensile strength initially increased and then decreased with increasing friction speed, reaching a maximum of 168.7 MPa at 4000 rpm, which is more than 60% of the aluminum alloy base material's tensile strength.
Exotic compounds of monovalent calcium synthesized at high pressure
Authors: Kong Jun , Shi Kaiyuan , Oganov Artem R. , Zhang Jiaqing , Su Lei , Dong Xiao 
Published: September 2024

It is well known that atoms of the same element in different valence states show very different chemical behaviors. Calcium is a typical divalent metal, sharing or losing both of its valence electrons when forming compounds. Attempts have been made to synthesize compounds of monovalent calcium ions for decades, but with very little success (e.g., in clusters). Pressure can result in substantial changes in the properties of atoms and chemical bonding, creating an extensive variety of unique materials with special valence states. In this study, using the ab initio evolutionary algorithm USPEX, we search for stable calcium–chlorine (Ca–Cl) system compounds at pressures up to 100 GPa. Besides the expected compound CaCl2, we predict three new compounds with monovalent Ca to be stable at high pressures, namely, CaCl, Ca5Cl6, and Ca3Cl4. According to our calculations, CaCl is stable at pressures above 18 GPa and is predicted to undergo a transition from nonmagnetic Fm-3m-CaCl to ferromagnetic Pm-3m-CaCl at 40 GPa. Ca5Cl6 and Ca3Cl4 are stable at pressures above 37 and 73 GPa, with space groups P-1 and R-3, respectively. Following these predictions, we successfully synthesized Pm-3m-CaCl in laser-heated diamond anvil cell experiments. The emergence of the unusual valence state at high pressures reveals exciting opportunities for creating entirely new materials in sufficiently large quantities for a variety of potential applications.
Improvement of voltage-controlled magnetic anisotropy effect by inserting an ultrathin metal capping layer
Authors: Nozaki Takayuki , Ichinose Tomohiro , Yamamoto Tatsuya , Yakushiji Kay , Yuasa Shinji 
Published: September 2024

We report systematic investigations of the effect of ultrathin capping layer insertion on the magnetic, magnetotransport, and voltage-controlled magnetic anisotropy (VCMA) properties in magnetic tunnel junctions (MTJs) with top free layer structure. Various kinds of ultrathin capping materials (Ir, Mo, TaB, Mg, Cr, Ti, and Ta) were introduced into the top free layer structure, which is comprised of MgO/CoFeB/X/MgO, where X is the inserted capping material. On insertion of an ultrathin Ir capping layer thinner than 0.3 nm, both the perpendicular magnetic anisotropy and the VCMA efficiency were improved by approximately a factor of two compared to the case without inserting an ultrathin metal capping layer. Mo insertion was also seen to be effective in improving the annealing tolerance. The developed structure can provide a novel approach for the development of high-performance voltage-driven MTJs, which can be applied, for example, for voltage-controlled magnetoresistive random access memory.
Ni3S2 particle–embedded nanotubes as a high-performance electrocatalyst for overall water splitting
Authors: Zhu Pengcheng , Ye Li , Li Xiaolei , Wang Tianxing , Zhong Yao , Zhuang Lin 
Published: September 2024

Hydrogen evolution reactions (HERs) and oxygen evolution reactions (OERs) are crucial for renewable energy production. Developing stable, cost-effective, and highly catalytic HER and OER electrocatalysts is paramount. In this study, a combination of hydrothermal synthesis and annealing was used to fabricate nickel sulfide (Ni3S2) particle–embedded nanotubes supported on nickel (Ni) foam (Ni3S2 PN/NF). The Ni3S2 PN/NF structures featured a highly branched morphology with a large specific surface area, surpassing that of conventional Ni metal nanotubes. This design increased the number of reactive sites and enhanced the charge-transfer process. The Ni foam substrate expanded the contact area of Ni3S2, thereby improving conductivity and facilitating the adsorption/desorption of intermediates on the Ni3S2 surface. Density functional theory calculations showed that the electronic structure of Ni3S2 provides excellent conductivity. Moreover, the multi-branched structure and inherent conductivity of the NiS nanomaterials enhanced the Ni3S2 PN/NF performance in 1M KOH, with overpotentials of 87 and 210 mV with iR compensation at 10 mA cm−2 for the HER and OER, respectively. The synthesized Ni3S2 PN/NF also exhibited robust durability for 20 h. These results demonstrate that Ni3S2 PN/NF is an excellent catalyst for both HER and OER.