bluuebunny/crossref_metadata_2025_split huggingface dataset:
Introducing and Validating the Cranial-Dorsal-Hip Angle (∠CDH): A
Method for Accurate Fetal Position Assessment in the First Trimester and Future
AI Applications
Authors: Tan Ying , Wen Huaxuan , Peng Guiyan , Wen Huiying , Wen Xin , Jiang Yao , Fan Jiaqi , Yuan Ying , Luo Dandan , Li Shengli 
Published: June 2024

Abstract
Purpose To introduce the cranial-dorsal-hip angle (∠CDH) as a novel
quantitative tool for assessing fetal position in the first trimester and to
validate its feasibility for future AI applications.
Materials and Methods 2520 first-trimester fetal NT exams with 2582 CRL
images (January-August 2022) were analyzed at a tertiary hospital as the pilot
group. Additionally, 1418 cases with 1450 fetal CRL images (September-December
2022) were examined for validation. Three expert sonographers defined a standard
for fetal positions. ∠CDH measurements, conducted by two ultrasound technicians,
were validated for consistency using Bland-Altman plots and the intra-class
correlation coefficient (ICC). This method allowed for categorizing fetal
positions as hyperflexion, neutral, and hyperextension based on ∠CDH.
Comparative accuracy was assessed against Ioannou, Wanyonyi, and Roux methods
using the weighted Kappa coefficient (k value).
Results The pilot group comprised 2186 fetal CRL images, and the
validation group included 1193 images. Measurement consistency was high (ICCs of
0.993; P<0.001). The established 95% reference range for ∠CDH in the neutral
fetal position was 118.3° to 137.8°. The ∠CDH method demonstrated superior
accuracy over the Ioannou, Wanyonyi, and Roux methods in both groups, with
accuracy rates of 94.5% (k values: 0.874, 95%CI: 0.852–0.896) in the pilot
group, and 92.6% (k values: 0.838, 95%CI: 0.806–0.871) in the validation group.
Conclusion The ∠CDH method has been validated as a highly reproducible and
accurate technique for first-trimester fetal position assessment. This sets the
stage for its potential future integration into intelligent assessment
models.
Relation of Transversus Abdominis to Rectus Abdominis Muscle in Various Anatomical Landmark Levels: A Cadaveric Study
Authors: Surichamorn Totsapol , Tantitham Thiti 
Published: June 2024

Abstract
Background Posterior Component Separation (PCS) is a surgical technique used in abdominal wall reconstruction. Understanding the relationship between the rectus abdominis and transversus abdominis muscles and the location of intercostal nerves is crucial for minimizing nerve injury during PCS. This cadaveric study aimed to investigate these anatomical relationships and propose practical guidelines for safer PCS procedures.
Methods Eighteen fresh cadavers were dissected to assess the overlap or separation of the rectus abdominis and transversus abdominis muscles at seven abdominal levels. The distance of intercostal nerves from the lateral border of the rectus abdominis was measured.
Results The study found that the muscles overlapped at the xiphoid and upper abdominal levels but began to separate below the 2/4 upper to umbilicus level. Intercostal nerves entered at varying distances from the lateral edge of the rectus abdominis, suggesting that levels above the 3/4 upper to umbilicus level are relatively safe for dissection.
Conclusion The study recommends initiating the first incision for PCS between the subxiphoid and 2/4 upper to the umbilicus, based on observed muscle relationships and nerve distances. This practical approach enhances safety and simplifies decision-making during surgery.
Value of green sign and chicken skin aspects for detecting malignancy of colorectal neoplasia in a prospective characterization study
Authors: Lafeuille Pierre , Rivory Jérôme , Lupu Alexandru , Rostain Florian , Jacques Jeremie , Wallenhorst Thimothee , Bartoli Adrien , Torti Serge , Fenouil Tanguy , Moll Frederic , Subtil Fabien , Pioche Mathieu 
Published: June 2024

Abstract
Background and study aims Accurate endoscopic characterization of colorectal lesions is essential for predicting histology but is difficult even for experts. Simple criteria could help endoscopists to detect and predict malignancy. The aim of this study was to evaluate the value of the green sign and chicken skin aspects in detection of malignant colorectal neoplasia.
Patients and methods We prospectively characterized and evaluated the histology of all consecutive colorectal lesions detected during screening or referred for endoscopic resection (Pro-CONECCT study). We evaluated the diagnostic accuracy of the green sign and chicken skin aspects for detection of superficial and deep invasive lesions.
Results 461 patients with 803 colorectal lesions were included. The green sign had a negative predictive value of 89.6% (95% confidence interval [CI] 87.1%–91.8%) and 98.1% (95% CI 96.7%-99.0%) for superficial and deep invasive lesions, respectively. In contrast to chicken skin, the green sign showed additional value for detection of both lesion types compared with the CONECCT classification and chicken skin (adjusted odds ratio [OR] for superficial lesions 5.9; 95% CI 3.4–10.2; P <0.001), adjusted OR for deep lesions 9.0; 95% CI 3.9–21.1; P <0.001).
Conclusions The green sign may be associated with malignant colorectal neoplasia. Targeting these areas before precise analysis of the lesion could be a way of improving detection of focal malignancies and prediction of the most severe histology.
Satisfying the multiple needs of older adults in rural China through the adaptation of dual polycentric systems
Authors: Dong Xiaowei , Qian Siwen 
Published: June 2024

AbstractThis study explores the fulfillment of multiple needs of older adults in rural China by adapting and aligning two polycentric systems from the perspective of intergenerational relationships. Utilizing the fuzzy-set Qualitative Comparative Analysis (fsQCA) methodology, it pinpoints crucial nesting points that facilitate the integration of the two systems. The study emphasizes maximizing the potential of these nesting points to achieve a cohesive systemic structure. Consequently, it suggests the development of an organizational-level polycentric framework that integrates the comparative advantages (on exploiting various nesting points) of various entities such as nuclear families, village self-governing organizations, government agencies, commercial enterprises, educational institutions, and others. This framework is capable of leveraging its spontaneous order to effectively tackle the challenges associated with ageing in rural areas. This study addresses the gap in the literature concerning an in-depth understanding of tackling rural ageing issues using a polycentric lens.
Transitioning to low-carbon agriculture: the non-linear role of digital inclusive finance in China’s agricultural carbon emissions
Authors: Li Hanjin , Tian Hu , Liu Xinyu , You Jiansheng 
Published: June 2024

AbstractPromoting low-carbon agricultural development is essential for achieving carbon neutrality and peak carbon emission goals. The emergence of digital inclusive finance has opened a new pathway to reduce agricultural carbon emissions. This study uses data from various provinces in China from 2011 to 2021 to explore the impact of digital inclusive finance on agricultural carbon emissions and its mechanism of action. The results show that during the study period, agricultural carbon emissions first increased and then decreased, with the emission gap between the eastern and western regions narrowing, while the gap between the southern and northern regions widened. Digital inclusive finance has an inverted “U-shaped” nonlinear impact on agricultural carbon emissions, with the depth of use and the degree of digitization being key factors. Agricultural carbon emissions only begin to be effectively suppressed when the scale of digital inclusive finance exceeds the peak value. Additionally, the development of agricultural green cooperatives weakens the emission reduction effect of digital inclusive finance, indicating a decoupling between their developments, while the accumulation of human capital enhances its emission reduction effect. Based on this, the government is advised to continue promoting low-carbon strategies and the development of digital inclusivity in rural areas. Financial institutions should develop financial products suitable for agricultural green cooperatives, and agricultural green cooperatives should also provide timely feedback and communication to achieve coordinated development between the two. Furthermore, education and training for farmers should be strengthened to encourage them to learn and adopt new technologies.
Report on EURAMET supplementary comparison on measurement of a 1 mm stage micrometer
Authors: Matus M , Pérez M del Mar , Prieto E , Germak A , Czułek D , Sosinowski P , Duță A , Dugheanu E , Zelenika S , Äremann M , Ozgur B , Asar M , Greeff P , Manana K , Sun S , Buajarern J , Brasil D A , Gastaldi B , Zechner G 
Published: June 2024

Main text
The results of the EURAMET supplementary comparison on the calibration of a 1 mm stage micrometer are reported. 13 NMIs from 4 RMOs participated in the comparison. Originally, the comparison was planned to use a single artefact. Because it was destroyed during the duration of the comparison, it was necessary to carry out the test in two loops using a new artefact. Artefact circulation started in August 2020 and was completed in September 2022.
Both artefacts were the same make and kind. The two artefacts are standard stage micrometers as used in optical microscopy on a transparent, low thermal expansion substrate. The scale length is 1 mm divided in 100 parts. The distances of all 100 scale marks from the zero mark have been measured by each participant.
The results with associated uncertainties of all participating NMIs were in good agreement. All En values were smaller than 1 already from the pre-draft A state on. Therefore, no separate analysis of a largest consistent subset was necessary. With 1400 values without a single outlier, it is tempting to assume that uncertainty contributions are somehow overestimated.
To reach the main text of this paper, click on Final Report. Note that this text is that which appears in Appendix B of the BIPM key comparison database https://www.bipm.org/kcdb/.
The final report has been peer-reviewed and approved for publication by the CCL, according to the provisions of the CIPM Mutual Recognition Arrangement (CIPM MRA).
Analysis and comparison of the orbit determination accuracy of TianQin based on multiple ground-based measurements
Authors: An Zicong , Shao Kai , Gu Defeng , Wei Chunbo , Tong Lisheng , Xu Zheyu , Li Ming , Wang Jian 
Published: June 2024

Abstract
TianQin project, a Chinese initiative in space gravitational wave detection, demands high precision in satellite orbit during both entry and scientific operations. As means of developmental maturation, ground-based measurements play a vital role in ensuring the smooth execution of TianQin satellite’s detection mission. This paper conducts a simulation analysis by utilizing various ground-based measurement data, including the China Deep Space Network (CDSN), S/Ka-band ranging system, and Satellite Laser Ranging (SLR). The main focus is to explore the distinctions in Precise Orbit Determination (POD) capabilities among different methods and to enhance POD accuracy through the integration of multiple techniques for TianQin satellites. The results indicate: (1) Leveraging a strategically positioned station distribution, CDSN stations offer extended observation time, averaging 17.3 h per satellite daily, compared to S/Ka’s 10.5 h. (2) In single-measurement POD scenarios, S/Ka proves superior, achieving accuracy better than 10 m and 0.4 mm s−1 for TianQin satellites with a 7-day orbit arc length. This superiority is attributed to its exceptional observational accuracy, outperforming CDSN’s 40 m and 2.2 mm s−1 for POD accuracy. (3) By integrating high-precision SLR data on the foundation of CDSN or S/Ka observations, the POD accuracy of TianQin satellites is further enhanced, despite the limited SLR data quantity.
Effect of distribution of fines on evolution of cooperation in spatial public goods game
Authors: Sun 孙 Xing-Ping 兴平 , Bi 毕 Yan-Zheng 研政 , Kang 康 Hong-Wei 洪炜 , Shen 沈 Yong 勇 , Chen 陈 Qing-Yi 清毅 
Published: June 2024

Abstract
In the realm of public goods game, punishment, as a potent tool, stands out for fostering cooperation. While it effectively addresses the first-order free-rider problem, the associated costs can be substantial. Punishers incur expenses in imposing sanctions, while defectors face fines. Unfortunately, these monetary elements seemingly vanish into thin air, representing a loss to the system itself. However, by virtue of the redistribution of fines to cooperators and punishers, not only can we mitigate this loss, but the rewards for these cooperative individuals can be enhanced. Based upon this premise, this paper introduces a fine distribution mechanism to the traditional pool punishment model. Under identical parameter settings, by conducting a comparative experiment with the conventional punishment model, the paper aims to investigate the impact of fine distribution on the evolution of cooperation in spatial public goods game. The experimental results clearly demonstrate that, in instances where the punishment cost is prohibitively high, the cooperative strategies of the traditional pool punishment model may completely collapse. However, the model enriched with fine distribution manages to sustain a considerable number of cooperative strategies, thus highlighting its effectiveness in promoting and preserving cooperation, even in the face of substantial punishment cost.
Current-perpendicular-to-plane transport properties of 2D ferromagnetic material CrTe2
Authors: Wang 王 Jin 瑾 , Liu 刘 Yu 宇 , Wang 王 Taikun 太坤 , Xu 徐 Yongkang 永康 , Wang 王 Shuanghai 双海 , He 何 Kun 坤 , Deng 邓 Yafeng 亚峰 , Yan 闫 Pengfei 鹏飞 , He 何 Liang 亮 
Published: June 2024

Abstract
Heterostructures of van der Waals (vdW) ferromagnetic materials have become a focal point in research of low-dimensional spintronic devices. The current direction in spin valves is commonly perpendicular to the plane (CPP). However, the transport properties of the CPP mode remain largely unexplored. In this work, current-in-plane (CIP) mode and CPP mode for CrTe2 thin films are carefully studied. The temperature-dependent longitudinal resistance transitions from metallic (CIP) to semiconductor behavior (CPP), with the electrical resistivity of CPP increased by five orders of magnitude. More importantly, the transport properties of the CPP can be categorized into a single-gap tunneling-through model with the activation energy (E
a) of ∼ 1.34 meV/gap at 300–150 K, the variable range hopping model with a linear negative magnetoresistance at 150–20 K, and weak localization region with a nonlinear magnetic resistance below 20 K. This study explores the vertical transport in CrTe2 materials for the first time, contributing to understand its unique properties and to pave the way for its potential in spin valve devices.
Corrigendum: Corrections to a proposal for three categories of units within the SI (2024 Metrologia 61 033001)
Authors: Lehman John , Migdall Alan , Scherschligt Julia , Whitehead Lorne 
Published: June 2024

Abstract
In this corrigendum, we correct several typographical or typesetting errors and small but meaningful errors in tables 1, A.1 and A.3 found in the original manuscript. We emphasize as a correction that the Avogadro constant is not a dimensionless number. The corrections are placed according to the original organization: section 2, references, and appendix.
Stability analysis of a hydropower plant containing pipe and channel flows
Authors: Zheng Yang , Liu Wanying , Chen Jinbao , Chen Qijuan , Xiao Zhihuai 
Published: June 2024

Abstract
This work studies the operational stability of the tailrace network containing mixed types of flows in a hydropower station with the complex frequency-domain networked transfer matrix method. First, the networked transfer matrix of the system plant is built based on the dynamic equations of the pipes, channels and hydraulic boundaries in the system. Then, the model is applied to analyze the stable state of the water conveyance network of a hydropower plant located in southwest China. The values of hydraulic state variables at the critical stable point under the multi-machine operating condition are obtained via eigenvalue analysis. The proposed overall transfer matrix model is proved to achieve satisfactory performance by the comparison of the statistic indexes obtained from modeling computation and those from the measured data.
Research on incipient and critical cavitation of a Francis turbine
Authors: Yang Jing , Yao Liang , Liu Jie , Yue Bo , Ma Zhe , Sun Yong , Wang Zhengwei 
Published: June 2024

Abstract
Cavitation is an important performance index to evaluate the comprehensive performance of hydraulic turbine. Determination of the plant cavitation coefficient is one of the most important tasks in the design phase of a hydro-power station. In order to improve the design rationality of the cavitation coefficient, numerical simulations of a Francis turbine were carried out to study the cavitation evolution characteristics. A detailed comparative analysis were made to clarify the different cavitation coefficients and impacts on the Francis turbine. Discussions on plant cavitation coefficient selection of hydro-power plant were made form the perspective of cavitation influence on the unit. Based on these investigations, it can be concluded that a certain safety margin of incipient and critical cavitation coefficient were needed considering the rapid efficiency drop near the critical cavitation and serious pressure pulsation near the incipient cavitation condition. The ratio between the plant cavitation coefficient and critical cavitation of the studied Francis turbine were larger than the current standard in China, which means the good cavitation performance of the unit after it put into operation. This study can provide a reference for determining the cavitation coefficient more accurately and ensuring the operation safety of the unit.
Design of Pelton Turbine Test Stand in Plateau Environment
Authors: Cai Jinhan , Zhou Xuejun , Luo Hongying , Wang Zhengwei 
Published: June 2024

Abstract
In recent years, with the continuous development of China’s hydropower projects, Pelton turbines are gradually being valued, and the focus of development has shifted from plain areas to plateau areas. Environmental impacts such as high altitude, water temperature, and high sediment content in the plateau area have caused serious interference to equipment that originally worked in a stable environment, for example, the failure of the cooperation between the parts of the turbine and the mutual seizure, the increased wear of the nozzle needle, the decrease of the flow rate and the water outlet speed of the nozzle, and the decrease of the air pressure in the plateau environment lead to the change of the flow state of the nozzle. In view of the above problems, this paper puts forward the design scheme of impulse turbine test-bed, using the method of changing specific speed to determine the basic parameters of impulse turbine unit, so as to eliminate the influence of plateau environment on the normal operation of turbine, obtain the efficiency condition of model experiment under low ambient pressure, and improve the operation efficiency and reliability of turbine unit.
Investigation on large fluctuation transient process of high head Pelton turbine
Authors: Gao J , Han L , Wang H J , Liu Y X , Wei X Z , Qin D Q 
Published: June 2024

Abstract
With the development of hydropower in southern western China, the Pelton turbine is the only choice in this ultra-high head condition which is nearly 1000 m. However, the complex coupling structure of the internal and external flow of the Pelton turbine, the change of flow pattern during the transition process, and the fluid-solid interaction of the bucket greatly increases the difficulty of accurate numerical simulation. Therefore, there are relatively few studies and applications on the transition process of the Pelton turbine. In this paper, the theoretical analysis, numerical calculation on the internal complex flow and the external characteristics of the turbine during the large fluctuation transition process are carried out in three aspects. First, the internal flow mechanism under optimized conditions is investigated, such as Dean vortex pairs, secondary flow, etc. And then analyze the influence of the flow state distribution on the jet flow. Secondly, study the instability and flow characteristics in the large fluctuation transition process of the opening and closing process of the nozzle, and predict the mechanism of the jet flow and the impact on the bucket during the dynamic process. Finally, study change of the hydraulic characteristics under the dynamic process which provides a theoretical guarantee for the safe operation of the Pelton turbine.
Investigation on formation mechanism of cavitation channel vortex in the runner of Francis turbine
Authors: Wu Guangkuan , Xue Qiyao , Guan Ziwu , Guojun Zhu , Feng Jianjun 
Published: June 2024

Abstract
Cavitation channel vortices generally cause flow state more complex in the runner, leading to the work efficiency is reduced and the cavitation erosion on flow components is enhanced. In this paper, simulation of cavitation flow is carried out for a Francis turbine model, and the evolution of vortices in the runner during cavitation development is analyzed under partial load conditions. The results show that cavitation has a great influence on the morphology and distribution of attached vortices between blades, trailing vortices at the outlet edge of the blades, and vortex near the cone in the runner. With the gradual development of cavitation, the invasion effect of vortex rope in draft tube on the runner is enhanced, and the vortex near runner cone is gradually connected as a whole. Under the effect of the downstream reverse pressure gradient in local low-pressure area, the flow separation area gradually expands to the blade and upstream, and more singular points evolve on flow separation lines, which leads to more trailing vortices at the outlet of the blade and cavitation channel vortices are formed in serious cavitation stage.
The influence of guide vane opening on internal cavitation of Francis turbine
Authors: Chen Minjia , Luo Xingqi , Feng Jianjun , Lv Siqin 
Published: June 2024

Abstract
In response to the theme of national multi energy complementary power grid construction, hydropower stations need to frequently change the opening of active guide vanes. Operation deviates from the rated working condition. And output is adjusted to meet the flexible power demand of users. Cavitation phenomenon as the biggest problem restricting the eccentric operation of Francis turbine. Easily induce cavitation damage to the flow passage components of the unit and shorten the service life of the unit. Therefore, there is a good engineering research background for the cavitation characteristics inside Francis turbines in the process of exploring the variation of guide vane opening. This paper takes a high head Francis turbine as the research object, based on numerical simulation and model test. The results show that the maximum amplitude of the draft tube vortex gradually increases during the process of decreasing the opening. The degree of cavitation is gradually serious, and the streamline distribution of the flow field inside the impeller is uneven. As the opening of the guide vane gradually increases, the vortexof the draft tube gradually decreases. The cavitation degree is weakened, and the streamline distribution inside the impeller is significantly improved. With the increase of the guide vane opening, the low-speed area on the outlet surface of the impeller gradually decreases, resulting in a gradual reduction of the low-speed zone in the straight cone section of the draft tube, a smaller vortex, a weaker cavitation degree. The internal flow distribution of the impeller is significantly improved.