bluuebunny/crossref_metadata_2025_split huggingface dataset:
Temperature behavior of the velocity autocorrelation function in large MD models of water
Authors: Anikeenko A. V. , Naberukhin Yu. I. 
Published: September 2024

Velocity autocorrelation functions (VACFs) were calculated using the molecular dynamics method in the TIP4P/2005 and SPC/E water models of 157 464 molecules at temperatures ranging from 250 to 370 K. The large size of the models and the high accuracy of the calculations allow us to reliably compute the long-time tails of the VACFs, showing that they systematically change shape from hydrodynamic (argon-like) at high temperatures to that typical of supercooled liquids at low temperatures. These tails in the range of 2–10 ps can be well fitted by a combination of two power functions: At−3/2 – Bt−β (A, B &gt; 0, β ≈ 2). It is found that the amplitude of the hydrodynamic asymptote, A, approaches zero as the temperature decreases, thereby rendering the negative power-law decay,−Bt−2, the dominant term within the specified time interval. The presence of a negative −Bt−2 decay in the time interval of 2–10 ps determines the specific shape of the VACF long-time tail of water, distinguishing it from ordinary simple liquids. The amplitude B, which is always non-zero, demonstrates a slight increase with rising temperature. At medium temperatures, weak but well-defined damped oscillations are observed on the VACF in the 0.5–2 ps interval.
Cardiac index as a surrogate marker for anxiety in pediatric patients undergoing ambulatory endoscopy: a prospective cohort study
Authors: Mai Christine L , Burns Sara , August David A , Bhattacharya Somaletha T , Mueller Ariel , Houle Timothy T , Anderson Thomas A , Peck Jacquelin 
Published: September 2024

Abstract

Objective. Pediatric patients undergoing medical procedures often grapple with preoperative anxiety, which can impact postoperative outcomes. While healthcare providers subjectively assess anxiety, objective quantification tools remain limited. This study aimed to evaluate two objective measures—cardiac index (CI) and heart rate (HR) in comparison with validated subjective assessments, the modified Yale Preoperative Anxiety Scale (mYPAS) and the numeric rating scale (NRS).

Approach. In this prospective, observational cohort study, children ages 5–17 undergoing ambulatory endoscopy under general anesthesia underwent simultaneous measurement of objective and subjective measures at various time points: baseline, intravenous placement, two-minutes post-IV placement, when departing the preoperative bay, and one-minute prior to anesthesia induction.

Main Results. Of the 86 enrolled patients, 77 had analyzable CI data and were included in the analysis. The median age was 15 years (interquartile range 13, 16), 55% were female, and most were American Society of Anesthesiologists (ASA) Physical Status 2 (64%), and had previous endoscopies (53%). HR and CI correlated overall (r = 0.65, 95% CI: 0.62, 0.69; p < 0.001), as did NRS and mYPAS (r = 0.39, 95% CI: 0.34, 0.44; p < 0.001). The correlation between HR and CI was stronger with NRS (r = 0.24, 95% CI: 0.19, 0.29; p < 0.001; and r = 0.13, 95% CI: 0.07, 0.19; p < 0.001, respectively) than with mYPAS (r = 0.06, 95% CI: 0.00, 0.11; p = 0.046; and r = 0.08, 95% CI: 0.02, 0.14; p = 0.006, respectively). The correlation with mYPAS for both HR and CI varied significantly in both direction and magnitude across the different time points.

Significance. A modest yet discernable correlation exists between objective measures (HR and CI) and established subjective anxiety assessments.
The Star Formation Histories, Star Formation Efficiencies and Ionizing Sources of ATLASGAL Clumps with H ii Regions
Authors: Zhou J. W. , Dib Sami , Kroupa Pavel 
Published: September 2024

Abstract
1226 ATLASGAL clumps with H ii regions (H ii-clumps) were matched with radio sources in the CORNISH-North/South surveys, and 392 of them have corresponding radio sources. We determined the stellar luminosity L
*,T84 according to the Lyman continuum flux N
Ly. When the bolometric luminosity of H ii-clumps is less than log10(L
bol,obs/L
⊙) ≈3.7, corresponding to a clump mass log10(M
cl/M
⊙) ≈ 2.55, the values of L
*,T84 derived from N
Ly overestimate the actual stellar luminosities, because the accretion onto the protostars contributes significantly to the radio emission. After subtracting the accretion luminosity from L
*,T84, we obtained reasonable estimates of the stellar luminosity. Using the 0.5 Myr isochrone, we calculated the stellar masses according to the stellar luminosities, and found that they roughly follow the

m

max

−

M

ecl

relation of embedded clusters, consistent with the ionizing sources representing the most massive stars in the embedded clusters of H ii-clumps. We also studied the contribution of the possible flaring activity to the observed stellar luminosity and found that they can be neglected. We further studied the change of SFE with the clump mass. According to the derived mass of the most massive star in each HII-clump, using the theoretical

m

max

−

M

ecl

relation, we calculated the mass of the corresponding embedded cluster and then the SFE of the clump. The SFE decreases with increasing clump mass, with a median value of ≈0.3. We also independently derived the SFE for each H ii-clump based on the model developed in our previous work. The SFEs of H ii-clumps derived from the observation and the model are in good agreement. Concerning the star formation histories of the ATLASGAL clumps, low-mass clumps may reach the peak of star formation earlier than high-mass clumps, consistent with the shorter free-fall time of low-mass clumps.
A rapid demodulation method for the interference spectrum of optical fiber sensors based on machine learning
Authors: Yue-Yu Xiao , Xin-Yu Xu , Yan-Xiang Lai 
Published: September 2024

Abstract
Interferometric optical fiber sensors based on wavelength demodulation play an important role in the field of high-precision measurements. Generally used wavelength tracking method is based on the locations of feature wavelengths (peaks or valleys), and a long time of spectrum scanning and demodulation is required. A rapid demodulation method based on machine learning is proposed in this paper, and a more efficient demodulation of the interference spectra of optical fiber sensors is achieved. It is demonstrated by numerical simulations and experiments that the demodulation performances of the machine learning method are far better than those of the wavelength tracking method when the sampling intervals are sparse. Under a certain accuracy requirement (coefficient of determination larger than 0.9900 and mean square error less than 0.10), the machine learning based method can demodulate the interference spectra with a maximum sampling interval of 8 nm or a minimum wavelength range of 8 nm without feature wavelengths. The demodulation speed can be therefore improved to 400 times that of the wavelength tracking method.
Critical needs to close monitoring gaps in pan-tropical wetland CH4 emissions
Authors: Zhu Qing , Yuan Kunxiaojia , Li Fa , Riley William J , Hoyt Alison , Jackson Robert , McNicol Gavin , Chen Min , Knox Sara H , Briner Otto , Beerling David , Gedney Nicola , Hopcroft Peter O , Ito Akihito , Jain Atul K , Jensen Katherine , Kleinen Thomas , Li Tingting , Liu Xiangyu , McDonald Kyle C , Melton Joe R , Miller Paul A , Müller Jurek , Peng Changhui , Poulter Benjamin , Qin Zhangcai , Peng Shushi , Tian Hanqin , Xu Xiaoming , Yao Yuanzhi , Xi Yi , Zhang Zhen , Zhang Wenxin , Zhu Qiuan , Zhuang Qianlai 
Published: September 2024

Abstract
Global wetlands are the largest and most uncertain natural source of atmospheric methane (CH4). The FLUXNET-CH4 synthesis initiative has established a global network of flux tower infrastructure, offering valuable data products and fostering a dedicated community for the measurement and analysis of methane flux data. Existing studies using the FLUXNET-CH4 Community Product v1.0 have provided invaluable insights into the drivers of ecosystem-to-regional spatial patterns and daily-to-decadal temporal dynamics in temperate, boreal, and Arctic climate regions. However, as the wetland CH4 monitoring network grows, there is a critical knowledge gap about where new monitoring infrastructure ought to be located to improve understanding of the global wetland CH4 budget. Here we address this gap with a spatial representativeness analysis at existing and hypothetical observation sites, using 16 process-based wetland biogeochemistry models and machine learning. We find that, in addition to eddy covariance monitoring sites, existing chamber sites are important complements, especially over high latitudes and the tropics. Furthermore, expanding the current monitoring network for wetland CH4 emissions should prioritize, first, tropical and second, sub-tropical semi-arid wetland regions. Considering those new hypothetical wetland sites from tropical and semi-arid climate zones could significantly improve global estimates of wetland CH4 emissions and reduce bias by 79% (from 76 to 16 TgCH4 y−1), compared with using solely existing monitoring networks. Our study thus demonstrates an approach for long-term strategic expansion of flux observations.
Uncovering disparities in water-based outdoor recreation using cell phone mobility data
Authors: Zhang Wendong , Wan Xibo , Fan Wenran , Ji Yongjie 
Published: September 2024

Abstract
Outdoor recreation plays a pivotal role in improving people’s physical and mental health, serving as a popular form of entertainment and a significant economic contributor. Limited access to these resources not only exacerbates health disparities but also deprives underserved areas of essential benefits like stress relief and community bonding, both of which are crucial for enhancing overall quality of life. This paper provides one of the first detailed analyses of water-based recreation at over 61 000 inland and coastal sites across the United States. We aim to explore disparities in recreational behavior across race, ethnicity, income, and socioeconomic status. Using Advan cellphone data from more than 70 million outdoor trips, representing 215 000 census block groups, we find that communities of color, rural areas, and socioeconomically disadvantaged groups are significantly underrepresented in water-based recreational visits. Despite living similar distances from recreational sites, these groups show notably different patterns in travel distance for water-based recreation. Additionally, we find Native Americans from underserved areas have to travel 3–5 times longer distances than other groups for water-based recreation. Our findings show that the extensive and frequent cellphone mobility data could reveal policy-relevant patterns especially those made by underserved Americans often overlooked in traditional household surveys.
Experimental Study of Mechanical Properties of Natural Fiber Polymer Composite
Authors: Gc V , Joshi R , Giri H , Sujakhu S , Shah M 
Published: September 2024

Abstract
Numerous studies and research projects have been conducted to develop natural fiber polymer composites. The researcher and engineers develop a composite by reinforcing natural fiber with a polymer that exhibits the desired mechanical properties. The experiment determines the composite’s mechanical properties, such as tensile, compression, flexural, and impact strength. This paper presents the experimental study of the natural fiber-reinforced composite, where hemp and jute fibers were reinforced with epoxy polymer as the test specimens for the experiment. The primary approach involved fabricating composite samples with fiber-weight fractions and matrix compositions. Then the appropriate sample is experimented with for its tensile strength, compression strength, and impact strength. Another property of the composite’s the composite’s water absorption was investigated through a water absorbability test. Key results show that composites containing a 30% weight fraction of natural hemp fiber demonstrated promising mechanical properties. This composite showed a tensile strength of 50 MPa, a compression strength of 55.6 N/m2, an impact strength of 58.9 kJ/m2, and a water absorbability of 7%. These results may offer valuable insight into the mechanical behavior of natural fiber composites, which can be used to optimize material design and engineering applications. Understanding the limitations and strengths of these composites allows for informed decision-making in selecting appropriate materials for specific engineering projects.
Backtesting of value at risk estimation methods for energy commodity trading: evaluating performance and identifying the optimal approach
Authors: Silwal N , Giri S R 
Published: September 2024

Abstract
This paper focuses on the application of Value at Risk (VaR) estimation techniques in the context of energy commodity trading, with a specific emphasis on the NYMEX (NG) and Title Transfer Facility (TTF) natural gas index. The primary point of this study is to break down and assess the VaR assessment strategies and recognize the most reasonable methodology. Historical price data for these commodities were collected, and forward prices were generated using a Long Short-Term Memory (LSTM) forecasting model. A portfolio comprising Future and Forward contracts for both NG and TTF index was constructed and three VaR estimation approaches: Variance-Covariance, Historical Simulation, and Monte Carlo Simulation were employed. Backtesting was then performed using the metric Quadratic Probability Score (QPS) to determine the optimal approach. Sensitivity analysis was also conducted to evaluate the variation in the estimated VaR values. The VaR values were determined using all three methods at different confidence interval and their backtesting was performed. The study found that the Monte Carlo Simulation approach outperforms other methods for estimating VaR in risk-averse trading scenarios with lowest QPS. It also underscores the need to consider individual contract risks within a portfolio, suggesting that diversification alone might not suffice in mitigating those risks.
Techno-Economic Feasibility Study of Solar Powered Rural Community Heat Grid System in Langtang
Authors: Ghimire M , Dahal P , Bhandari S , Kandel R , Niroula Y , Pandit S , Shrestha S , Shah M 
Published: September 2024

Abstract
Langtang, a popular tourist destination in Nepal’s northern Himalayas, relies heavily on solid fuels like coal, wood, and LPG, accounting for 99.3% of its energy demand. This reliance is a significant source of greenhouse gas emissions and deforestation. The proposed study provides a green alternative by utilizing heat that would otherwise be squandered with benefits including avoided cost of energy, through which the use of surplus and wasted heat energy, and reduced investment in individual household or building heating equipment. This paper conducts a feasibility study to assess technical and economic viabilities of introducing a solar water heater reinforced rural heat grid network in the region. The technical feasibility of this system is determined using TRNSYS and Polysun to see if the proposed system provide at least 60% solar fraction in all seasons, while economic analysis is conducted using Benefit Cost Ratio (BCR) and discounted payback period. A pilot project was carried out for five households for demonstration, which showed that the heating demand of each house could be met by 40 different 15-tube solar collectors, resulting in energy savings of 2,28,000 kWh and reducing 25,423 kgs of CO2 annually. The financial analysis revealed a BCR of 1.45 and a payback period of 14 years, showing that heat grid network is techno-economically viable for rural communities of Nepal.
Investigating the potential advancements for electric vehicle charging technologies through various converters topology
Authors: N S Jayalakshmi , Sathe Madhurika , Pandey Anubhav Kumar , Jadoun Vinay Kumar 
Published: September 2024

Abstract
In the era of various automobiles, petrol and diesel vehicles proved to be the best-suited means of transportation. However, the adverse impacts of these fuels on the atmosphere have propelled the world to approach and promote electrified transportation. It is essential to comprehensively discuss various integral aspects of Electric Vehicles (EVs) especially the battery technology, battery charging schemes, standards and management. This paper discusses the importance of various new technologies proposed for the fast charging of EVs in which a detailed analysis of one such attractive and promising technology i.e., Solid-State Transformers (SST) built EV charging station. The work also reviews ample of versatile options available for the user, offered by charging systems that can handle high-power charging. The cost-effective technology, efficient power transfer, compactness and flexibility is a promising solutions for fast charging technology in which the integral parts are rectifiers and DC-DC converters which are given due emphasis in this study. These components are unidirectional and bidirectional, with simple or complex controls. A detailed discussion of these various topologies is discussed for suitable and maximum utilization of the charging system. The technologies that can offer vehicle-to-grid (V2G) enabled bidirectional power transfer, connectivity and metering suitability are discussed. These various challenges are addressed, including the development of charging technologies and infrastructure to make it easily accessible to its users. Further, a detailed discussion on the types and parts of SST involving various charging methods in line with their advantages and limitations is emphasized.
Assessing hidden corrosion in AZ91 magnesium alloy via infrared thermography in simulated atmospheric acid rain conditions
Authors: L Yadhu Balakrishna , K Janani Archana , K Arjun , Balasubramanian Karthikeyan 
Published: September 2024

Abstract
Magnesium alloys have garnered significant attention in the aerospace and marine industries due to their exceptional mechanical properties, including low density and a high strength-to-weight ratio. Despite these advantages, their widespread adoption is hindered by susceptibility to corrosion, particularly under harsh environmental conditions. While considerable research has focused on uniform surface corrosion of magnesium alloys, studies addressing hidden corrosion remain limited. Hidden corrosion is a critical defect that can severely compromise the structural integrity of aging aircraft. In this study, the hidden corrosion behavior of the AZ91 magnesium alloy was explored using infrared thermographic non-destructive testing. Seven blind holes were drilled into the surface of the alloy, which was then exposed to simulated acid rain for ten days to examine the effects of corrosion. The rate of corrosion in the drilled samples was observed to be slightly higher compared to bare samples, likely due to the accumulation of acid in the crevices. Changes in the initial and final hole dimensions and volume were used to determine the corrosion rate, providing valuable insights into the mechanisms governing hidden corrosion in magnesium alloys. This work offers a deeper understanding of hidden corrosion, with potential implications for improving the longevity and safety of critical aerospace and marine components.
J.R.R. Tolkien: A Very Short Introduction
Authors: Townend Matthew 
Published: September 2024

Abstract
J. R. R Tolkien: A Very Short Introduction provides a compact overview and analysis of the life and works of J. R. R. Tolkien, who wrote two of the most extraordinary and influential books of the twentieth century. For millions of readers in the modern world, The Hobbit and The Lord of the Rings have offered a form of re-enchantment, and have opened a door to myth and fairy tales, and to the discovery of fantasy literature. This VSI offers an accessible and authoritative guide to the full range of Tolkien’s extensive writings, including his posthumously published work. It examines the writings of Tolkien in the time and context of their composition, and explores Tolkien’s characteristic ideas, preoccupations, and artistry.
Elegy
Authors: Townend Matthew 
Published: September 2024

Abstract
This chapter explores how many of J. R. R. Tolkien’s works are characterized by a deep sense of loss. It examines how Tolkien’s war experiences affected his writings, and presents some of the many ways in which The Lord of the Rings in particular is marked by an elegiac sense of time, exile, and the vanished past. The chapter further explores Tolkien’s Christian preoccupation with failure, ‘fallenness’, and pity. It concludes by looking at Tolkien’s idea of the ‘eucatastrophe’ or happy ending, a feature of fairy tales which he views as fundamentally Christian, and which, in his own works, he re-presented to modern culture in a new and influential form.
Grass leaf structural and stomatal trait responses to climate gradients assessed over the 20th century and across the Great Plains, USA
Authors: Donnelly Ryan C , Nippert Jesse B , Wedel Emily R , Ferguson Carolyn J 
Published: September 2024

Abstract
Abstract. Using herbarium specimens spanning 133 years and field-collected measurements, we assessed intraspecific trait (leaf structural and stomatal) variability from grass species in the Great Plains of North America. We focused on two widespread, closely related grasses from the tribe Paniceae: Dichanthelium oligosanthes subsp. scribnerianum (C3) and Panicum virgatum (C4). Thirty-one specimens per taxon were sampled from local herbaria from the years 1887 to 2013 to assess trait responses across time to changes in atmospheric [CO2] and growing season precipitation and temperature. In 2021 and 2022, the species were measured from eight grasslands sites to explore how traits vary spatially across natural continental precipitation and temperature gradients.
Δ13C increased with atmospheric [CO2] for D. oligosanthes but decreased for P. virgatum, likely linked to increases in precipitation in the study region over the past century. Notably, this is the first record of decreasing Δ13C over time for a C4 species illustrating 13C linkages to climate. As atmospheric [CO2] increased, C:N increased and δ15N decreased for both species and %N decreased for D. oligosanthes. Across a large precipitation gradient, D. oligosanthes leaf traits were more responsive to changes in precipitation than those of P. virgatum. In contrast, only two traits of P. virgatum responded to increases in temperature across a gradient: specific leaf area (increase) and leaf dry matter content (decrease). The only shared significant trend between species was increased C:N with precipitation. Our work demonstrates that these closely related grass species with different photosynthetic pathways exhibited various trait responses across temporal and spatial scales, illustrating the key role of scale of inquiry for forecasting leaf trait responses to future environmental change.
NASTRA: accurate analysis of short tandem repeat markers by nanopore sequencing with repeat-structure-aware algorithm
Authors: Ren Zilin , Zhang Jiarong , Zhang Yixiang , Yang Tingting , Sun Pingping , Xue Jiguo , Bo Xiaochen , Zhou Bo , Yan Jiangwei , Ni Ming 
Published: September 2024

Abstract
Short-tandem repeats (STRs) are the type of genetic markers extensively utilized in biomedical and forensic applications. Due to sequencing noise in nanopore sequencing, accurate analysis methods are lacking. We developed NASTRA, an innovative tool for Nanopore Autosomal Short Tandem Repeat Analysis, which overcomes traditional database-based methods’ limitations and provides a precise germline analysis of STR genetic markers without the need for allele sequence reference. Demonstrating high accuracy in cell line authentication testing and paternity testing, NASTRA significantly surpasses existing methods in both speed and accuracy. This advancement makes it a promising solution for rapid cell line authentication and kinship testing, highlighting the potential of nanopore sequencing for in-field applications.