bluuebunny/crossref_metadata_2025_split huggingface dataset:
Coping with unforeseen circumstances: the COVID-19 crisis and bus contract renegotiation in Sweden
Authors: Alexandersson Gunnar , Hultén Staffan , Henriksson Lars 
Published: May 2024

AbstractIn principle, competitively tendered contracts in Swedish public bus transport are not supposed to be renegotiated during the contract period. In practice, it happens quite frequently. The need for renegotiations became evident during the COVID-19 crisis. This external shock to the system was unusually strong. Demand for bus services dropped abruptly, affecting revenues of procuring authorities and, depending on contract type, also bus operators. To make the situation even worse, costs typically remained constant, as frequent services were supposed to be upheld to avoid the spreading of the virus in crowded buses. Contract renegotiations during the COVID-19 crisis were clearly caused by unexpected exogenous events. Contracts with passenger incentives, linking a substantial part of compensation to the number of passengers, have been more likely to be renegotiated than gross-cost contracts, which were easier to adjust to the drop in demand. Typically, renegotiations were triggered by operators. While being a pragmatically rational response to an extreme situation, the renegotiations and their outcome may not in all cases have been compliant with the legal framework for public procurements, even when taking into account the exemptions made possible by the framework. In cases where passenger incentive contracts have been transformed into gross-cost contracts it could be argued that the nature of the contract has been changed. A new tender should then probably have been performed instead, although this has not been tried in court. The COVID-19 crisis could have long-term impact on contracts and procurements in the industry, affecting how effective competition will be in future tenders. For now, gross-cost contracts seem to be the norm, and it is possible that passenger-incentive contracts will become less common overall. One way to handle unexpected events with profound impact could be to include so-called threat-points that trigger renegotiation of a contract.
The effect of 2020 lockdown on bank internal ratings
Authors: Calcagnini Giorgio , Favaretto Federico , Giombini Germana 
Published: May 2024

AbstractWe investigate how banks’ internal ratings were affected by the first lockdown shock in Italy (March-June 2020). Using monthly proprietary data from a regional bank between October 2019 and January 2022, and adding credit registry data and balance sheet data of client firms, we estimate the lockdown effect on the change in six different ratings assigned by the bank to client firms in June 2020 and December 2020. We obtain three main results. First, controlling for both supply and demand factors, the lockdown is associated with a decline in four of the six ratings. Second, the lockdown effect also depends on specific firm characteristics, i.e. the lockdown effect appears to be mitigated in the presence of high turnover or for firms belonging to essential sectors. However, these interaction effects do not hold for all ratings, suggesting that each type of rating is influenced by different firm characteristics. Third, once we consider a full interaction model, the lockdown effect disappears in the medium term.
Grounding Fault Diagnosis of Running Rails Based on a Multi-scale One-Dimensional Convolutional Neural Network in a DC Subway System
Authors: Du Guifu , Liu Na , Zhang Dongliang , Li Qiaoyue , Sun Jianxiang , Jiang Xingxing , Zhu Zhongkui 
Published: May 2024

AbstractRunning rails are the return conductors of the traction current in DC subway systems, which should be insulated from the earth. Due to the large length of the line, as well as the humidity and metal dust in the tunnel, grounding fault of the running rails usually occurs, which will increase stray current (SC) leakage and endanger power supply safety. In this paper, a method of grounding fault diagnosis of running rails based on a multi-scale one-dimensional convolutional neural network (MS-1DCNN) is proposed. Firstly, a platform for the dynamic distribution of SC and rail potential (RP) with grounding faults existing in the running rails is established, which generates the dynamic RP data with various grounding faults. Secondly, a grounding fault diagnostic method of running rails based on MS-1DCNN is proposed, so as to realize the effective identification of ground fault types in subway systems. Thirdly, with the proposed diagnostic method, the datasets under two operating conditions of a single train and two trains are tested; a comparison test between MS-1DCNN and the 1D convolutional neural network (1DCNN) is carried out, and the effectiveness of the proposed method is verified. Results demonstrate that the proposed model can significantly improve the ground fault diagnostic accuracy of running rails. The dynamic RP simulation platform for trains established in this paper lays a theoretical foundation for the grounding fault research of running rail. Moreover, the deep learning method is proposed for the first time to diagnose the grounding fault of running rail, and the high diagnostic accuracy is obtained, which is of great significance for the safe and stable operation of the subway line.
A hybrid congestion control scheme for Named Data Networking via SDN
Authors: Ma Tianxiang , Pang Xianhai , Zeng Siming , Fan Hui , Luo Peng , Jia Boyan , Hou Yajun 
Published: May 2024

AbstractAs the mainstream congestion control in Named Data Networking (NDN), the hybrid control mechanism integrates the advantages of consumer and router control mechanisms. However, The concurrent control by both consumers and routers may results in degraded data transmission performance. Therefore, we propose a novel hybrid congestion control scheme for NDN, called ndnSieve. By using the characteristics of Software Defined Network (SDN) that can achieve global network information acquisition as well as global resource scheduling, ndnSieve manages to invoke consumer and router control mechanisms based on different congestion states in the network respectively and achieves the synergy between two kinds of mechanisms. The results of experiment demonstrate that, compared with existing works, ndnSieve has the lowest average round-trip time, relatively high level of throughput and fairness, effectively improving the Quality of Service (QoS) of the network.
Multipliers and equivalence of functions, spaces, and operators
Authors: Câmara M. C. , Carteiro C. , Ross W. T. 
Published: May 2024

AbstractBy interpreting the well-known Brown–Halmos theorem for Toeplitz operators in terms of multipliers, we formulate a Brown–Halmos analogue for the product of generalized Toeplitz operators, defined as compressions of multiplication operators to closed subspaces of $$L^2({\mathbb {T}})$$

L
2

(
T
)

. We use this to define equivalences between two operators in that class by means of multipliers between the spaces where they act. Necessary and sufficient conditions for such an equivalence to be unitary or a similarity are established. The results are applied to Toeplitz and Hankel operators, truncated Toeplitz operators, and dual truncated Toeplitz operators.
The role of physical medicine and rehabilitation in the management of a pediatric female with Möbius syndrome: a case report
Authors: Al-Ajlouni Yazan A. , Lihaz Maysa , Islam Mohammad 
Published: May 2024

AbstractThis case report presents a comprehensive analysis of a 4-year-old female patient with Möbius syndrome and associated conditions while emphasizing the role of pediatric physical medicine and rehabilitation (PM&R) in managing her complex medical profile. The patient’s clinical presentation encompassed congenital facial palsy, ocular abduction impairments, developmental delay, syndactyly, clubfoot, and G-tube dependence. The diagnosis was based on characteristic clinical criteria of Möbius syndrome. A multifaceted PM&R approach was employed, involving tailored physical therapy interventions targeting head control, sensory integration, trunk rotation, and positioning techniques. Concurrently, occupational therapy strategies enhanced her functional abilities and empowered caregivers with home-based support techniques. Long-term management considerations highlighted the potential of home-based and school-based therapies, emphasizing multidisciplinary collaboration for sustained progress. The case report underscores the effectiveness of PM&R in addressing the intricate challenges of Möbius syndrome and related conditions, offering insights for future clinical practice and research.
Meta-optimization of resources on quantum computers
Authors: Mohammad Ijaz Ahamed , Pivoluska Matej , Plesch Martin 
Published: May 2024

AbstractThe current state of quantum computing is commonly described as the Noisy Intermediate-Scale Quantum era. Available computers contain a few dozens of qubits and can perform a few dozens of operations before the inevitable noise erases all information encoded in the calculation. Even if the technology advances fast within the next years, any use of quantum computers will be limited to short and simple tasks, serving as subroutines of more complex classical procedures. Even for these applications the resource efficiency, measured in the number of quantum computer runs, will be a key parameter. Here we suggest a general meta-optimization procedure for hybrid quantum-classical algorithms that allows finding the optimal approach with limited quantum resources. This method optimizes the usage of resources of an existing method by testing its capabilities and setting the optimal resource utilization. We demonstrate this procedure on a specific example of variational quantum algorithm used to find the ground state energy of a hydrogen molecule.
The impact of sunlight exposure on brain structural markers in the UK Biobank
Authors: Li Huihui , Cui Fusheng , Wang Tong , Wang Weijing , Zhang Dongfeng 
Published: May 2024

AbstractSunlight is closely intertwined with daily life. It remains unclear whether there are associations between sunlight exposure and brain structural markers. General linear regression analysis was used to compare the differences in brain structural markers among different sunlight exposure time groups. Stratification analyses were performed based on sex, age, and diseases (hypertension, stroke, diabetes). Restricted cubic spline was performed to examine the dose–response relationship between natural sunlight exposure and brain structural markers, with further stratification by season. A negative association of sunlight exposure time with brain structural markers was found in the upper tertile compared to the lower tertile. Prolonged natural sunlight exposure was associated with the volumes of total brain (β: − 0.051, P < 0.001), white matter (β: − 0.031, P = 0.023), gray matter (β: − 0.067, P < 0.001), and white matter hyperintensities (β: 0.059, P < 0.001). These associations were more pronounced in males and individuals under the age of 60. The results of the restricted cubic spline analysis showed a nonlinear relationship between sunlight exposure and brain structural markers, with the direction changing around 2 h of sunlight exposure. This study demonstrates that prolonged exposure to natural sunlight is associated with brain structural markers change.
An improved manta ray foraging optimization algorithm
Authors: Qu Pengju , Yuan Qingni , Du Feilong , Gao Qingyang 
Published: May 2024

AbstractThe Manta Ray Foraging Optimization Algorithm (MRFO) is a metaheuristic algorithm for solving real-world problems. However, MRFO suffers from slow convergence precision and is easily trapped in a local optimal. Hence, to overcome these deficiencies, this paper proposes an Improved MRFO algorithm (IMRFO) that employs Tent chaotic mapping, the bidirectional search strategy, and the Levy flight strategy. Among these strategies, Tent chaotic mapping distributes the manta ray more uniformly and improves the quality of the initial solution, while the bidirectional search strategy expands the search area. The Levy flight strategy strengthens the algorithm’s ability to escape from local optimal. To verify IMRFO’s performance, the algorithm is compared with 10 other algorithms on 23 benchmark functions, the CEC2017 and CEC2022 benchmark suites, and five engineering problems, with statistical analysis illustrating the superiority and significance of the difference between IMRFO and other algorithms. The results indicate that the IMRFO outperforms the competitor optimization algorithms.
Stress and deformation analysis of the steel pipe arch integral lifting construction process of a continuous beam arch bridge
Authors: Xiang Hui , Xia Dadong , Wang Sheng , Zhang Zizheng , Luo Shang , Chen Wei 
Published: May 2024

AbstractThe Changjinghuang Railway Xinjiang Xizhi Bridge is a (90 + 180 + 90) m continuous beam arch bridge, and the arch rib steel pipe installation adopts “short bracket assembly and overall lifting method”. In order to ensure the accuracy of closure, the stress and deformation of the arch rib and bracket must be strictly controlled. Midas Civil is used to establish the finite element model to simulate the overall lifting construction process of the arch rib. Based on the model, the stress and deformation of the arch rib and the supports are analyzed, and the determination method of the horizontal cable force under temperature variations is proposed. The results show that the stress and deformation of the arch rib and bracket meet the requirements. Considering the variation of temperature, the tension force of the horizontal cables is taken as 200 t. The construction plan proposed under the guidance of numerical calculation results has been proven by practical engineering to meet the requirement of closure accuracy, which can be used as a reference for similar projects.
Contrasting neurofunctional correlates of face- and visuospatial-processing in children and adolescents with Williams syndrome: convergent results from four fMRI paradigms
Authors: Garvey Madeline H. , Nash Tiffany , Kippenhan J. Shane , Kohn Philip , Mervis Carolyn B. , Eisenberg Daniel P. , Ye Jean , Gregory Michael D. , Berman Karen F. 
Published: May 2024

AbstractUnderstanding neurogenetic mechanisms underlying neuropsychiatric disorders such as schizophrenia and autism is complicated by their inherent clinical and genetic heterogeneity. Williams syndrome (WS), a rare neurodevelopmental condition in which both the genetic alteration (hemideletion of ~ twenty-six 7q11.23 genes) and the cognitive/behavioral profile are well-defined, offers an invaluable opportunity to delineate gene-brain-behavior relationships. People with WS are characterized by increased social drive, including particular interest in faces, together with hallmark difficulty in visuospatial processing. Prior work, primarily in adults with WS, has searched for neural correlates of these characteristics, with reports of altered fusiform gyrus function while viewing socioemotional stimuli such as faces, along with hypoactivation of the intraparietal sulcus during visuospatial processing. Here, we investigated neural function in children and adolescents with WS by using four separate fMRI paradigms, two that probe each of these two cognitive/behavioral domains. During the two visuospatial tasks, but not during the two face processing tasks, we found bilateral intraparietal sulcus hypoactivation in WS. In contrast, during both face processing tasks, but not during the visuospatial tasks, we found fusiform hyperactivation. These data not only demonstrate that previous findings in adults with WS are also present in childhood and adolescence, but also provide a clear example that genetic mechanisms can bias neural circuit function, thereby affecting behavioral traits.
Observation of exceptionally strong near-bottom flows over the Atlantis II Seamounts in the northwest Atlantic
Authors: Godin Oleg A. , Tan Tsu Wei , Joseph John E. , Walters Matthew W. 
Published: May 2024

AbstractKnowledge of near-bottom ocean current velocities and especially their extreme values is necessary to understand geomorphology of the seafloor and composition of benthic biological communities and quantify mechanical energy dissipation by bottom drag. Direct measurements of near-bottom currents in deep ocean remain scarce because of logistical challenges. Here, we report the results of flow velocity and pressure fluctuation measurements at three sites with depths of 2573–4443 m in the area where the Gulf Stream interacts with the New England Seamounts. Repeated episodes of unexpectedly strong near-bottom currents were observed, with the current speed at 4443 m of more than 0.40 m/s. At 2573 m, current speeds exceeded 0.20 m/s approximately 5% of the time throughout the entire eight-week measurement period. The maximum flow speeds of over 1.10 m/s recorded at this site significantly surpass the fastest previously reported directly measured current speeds at comparable or larger depths. A strong correlation is found between the noise intensity in the infrasonic band and the measured current speed. The noise intensity and the characteristic frequency increase with the increasing current speed. Machine-learning tools are employed to infer current speeds from flow-noise measurements at the site not equipped with a current meter.
Differential analysis of histopathological and genetic markers of cancer aggressiveness, and survival difference in EBV-positive and EBV-negative prostate carcinoma
Authors: Ahmed Khalid , Sheikh Alisalman , Fatima Saira , Ghulam Tahira , Haider Ghulam , Abbas Farhat , Sarria-Santamera Antonio , Ghias Kulsoom , Mughal Nouman , Abidi Syed Hani 
Published: May 2024

AbstractSeveral studies have shown an association between prostate carcinoma (PCa) and Epstein-Barr virus (EBV); however, none of the studies so far have identified the histopathological and genetic markers of cancer aggressiveness associated with EBV in PCa tissues. In this study, we used previously characterized EBV-PCR-positive (n = 39) and EBV-negative (n = 60) PCa tissues to perform an IHC-based assessment of key histopathological and molecular markers of PCa aggressiveness (EMT markers, AR expression, perineural invasion, and lymphocytic infiltration characterization). Additionally, we investigated the differential expression of key oncogenes, EMT-associated genes, and PCa-specific oncomiRs, in EBV-positive and -negative tissues, using the qPCR array. Finally, survival benefit analysis was also performed in EBV-positive and EBV-negative PCa patients. The EBV-positive PCa exhibited a higher percentage (80%) of perineural invasion (PNI) compared to EBV-negative PCa (67.3%) samples. Similarly, a higher lymphocytic infiltration was observed in EBV-LMP1-positive PCa samples. The subset characterization of T and B cell lymphocytic infiltration showed a trend of higher intratumoral and tumor stromal lymphocytic infiltration in EBV-negative tissues compared with EBV-positive tissues. The logistic regression analysis showed that EBV-positive status was associated with decreased odds (OR = 0.07; p-value < 0.019) of CD3 intratumoral lymphocytic infiltration in PCa tissues. The analysis of IHC-based expression patterns of EMT markers showed comparable expression of all EMT markers, except vimentin, which showed higher expression in EBV-positive PCa tissues compared to EBV-negative PCa tissues. Furthermore, gene expression analysis showed a statistically significant difference (p < 0.05) in the expression of CDH1, AR, CHEK-2, CDKN-1B, and CDC-20 and oncomiRs miR-126, miR-152-3p, miR-452, miR-145-3p, miR-196a, miR-183-3p, and miR-146b in EBV-positive PCa tissues compared to EBV-negative PCa tissues. Overall, the survival proportion was comparable in both groups. The presence of EBV in the PCa tissues results in an increased expression of certain oncogenes, oncomiRs, and EMT marker (vimentin) and a decrease in CD3 ITL, which may be associated with the aggressive forms of PCa.
Challenges for room temperature operation of electrically pumped GeSn lasers
Authors: Ellis A. R. , Duffy D. A. , Marko I. P. , Acharya S. , Du W. , Yu S. Q-. , Sweeney S. J. 
Published: May 2024

AbstractRecent demonstrations of room-temperature lasing in optically pumped GeSn show promise for future CMOS compatible lasers for Si-photonics applications. However, challenges remain for electrically pumped devices. Investigation of the processes that limit device performance is therefore vital in aiding the production of future commercial devices. In this work, a combined experimental and modelling approach is utilised to explore the dominant loss processes in current devices. By manipulating the band structure of functioning devices using high hydrostatic pressure techniques at low temperature, the dominant carrier recombination pathways are identified. This reveals that 93$$~\pm ~$$

±

5% of the threshold current is attributable to defect-related recombination at a temperature, T = 85 K. Furthermore, carrier occupation of L-valley states (carrier leakage) is responsible for 1.1$$~\pm ~$$

±

0.3% of the threshold current, but this sharply increases to 50% with a decrease of just 30 meV in the L-$$\Gamma$$
Γ
separation energy. This indicates that thermal broadening of a similar order may reproduce these adverse effects, limiting device performance at higher temperatures. Temperature dependent calculations show that carrier occupation of indirect valley L-states strongly affects the transparency carrier density and is therefore very sensitive to the Sn composition, leading to an effective operational temperature range for given Sn compositions and strain values. Recommendations for future device designs are proposed based on band structure and growth optimisations.
Study on plasma metabolomics profiling of depression in Chinese community-dwelling older adults based on untargeted LC/GC‒MS
Authors: Guo Jiangling , Han Peipei , Zheng Yaqing , Wu Yahui , Zheng Kai , Huang Chuanjun , Wang Yue , Chen Cheng , Qi Yiqiong , Chen Xiaoyu , Tao Qiongying , Zhai Jiayi , Guo Qi 
Published: May 2024

AbstractDepression is a serious psychiatric illness that causes great inconvenience to the lives of elderly individuals. However, the diagnosis of depression is somewhat subjective. Nontargeted gas chromatography (GC)/liquid chromatography (LC)–mass spectrometry (MS) was used to study the plasma metabolic profile and identify objective markers for depression and metabolic pathway variation. We recruited 379 Chinese community-dwelling individuals aged ≥ 65. Plasma samples were collected and detected by GC/LC‒MS. Orthogonal partial least squares discriminant analysis and a heatmap were utilized to distinguish the metabolites. Receiver operating characteristic curves were constructed to evaluate the diagnostic value of these differential metabolites. Additionally, metabolic pathway enrichment was performed to reveal metabolic pathway variation. According to our standard, 49 people were included in the depression cohort (DC), and 49 people age- and sex-matched individuals were included in the non-depression cohort (NDC). 64 metabolites identified via GC‒MS and 73 metabolites identified via LC‒MS had significant contributions to the differentiation between the DC and NDC, with VIP values > 1 and p values < 0.05. Three substances were detected by both methods: hypoxanthine, phytosphingosine, and xanthine. Furthermore, 1-(sn-glycero-3-phospho)-1D-myo-inositol had the largest area under the curve (AUC) value (AUC = 0.842). The purine metabolic pathway is the most important change in metabolic pathways. These findings show that there were differences in plasma metabolites between the depression cohort and the non-depression cohort. These identified differential metabolites may be markers of depression and can be used to study the changes in depression metabolic pathways.