bluuebunny/crossref_metadata_2025_split huggingface dataset:
Can preoperative 25-hydroxyvitamin D levels predict transient hypocalcemia after total thyroidectomy?
Authors: Saibene Alberto Maria , Rosso Cecilia , Felisati Giovanni , Pipolo Carlotta , De Leo Simone , Lozza Paolo , Cozzolino Mario Gennaro , De Pasquale Loredana 
Published: September 2021

AbstractTransient postoperative hypocalcemia is a common complication after total thyroidectomy. Evidence on contributing metabolic factors is contradictory. Our work aims to define the role of preoperative 25-hydroxyvitaminD levels in developing transient postoperative hypocalcemia. 183 consecutive patients who underwent total thyroidectomy at our institution (May 2017–December 2019) were included in the retrospective study. We reported gender, age, estimated glomerular filtration rate, creatinine, preoperative 25-hydroxyvitaminD, serum pre- and postoperative calcium, pre- and postoperative PTH levels and transient postoperative hypocalcemia occurrences. We compared variables both among patients with and without transient postoperative hypocalcemia and between patients with different 25-hydroxyvitaminD levels (< 10 ng/ml deficitary; 11–30 ng/ml insufficient; > 30 ng/ml, normal). A binomial logistic regression model evaluating the risk for transient postoperative hypocalcemia was elaborated. Patients with transient postoperative hypocalcemia had lower levels of postoperative PTH (p < 0.001) and more frequently normal or deficitary 25-hydroxyvitaminD levels (p = 0.05). When comparing patients according to their 25-hydroxyvitaminD levels, insufficiency was associated with a lower rate of transient postoperative hypocalcemia (p = 0.05); deficiency was associated with higher preoperative PTH (p = 0.021), postoperative PTH (p = 0.043) and estimated glomerular filtration rate (p = 0.031) and lower serum creatinine (p = 0.014). In the regression model higher preoperative PTH (OR = 1.011, p = 0.041) and 25-hydroxyvitaminD deficiency (OR = 0.343, p = 0.011) significantly predicted transient postoperative hypocalcemia. Data analysis revealed a correlation between transient postoperative hypocalcemia and 25-hydroxyvitaminD levels: our work points towards the possibility to stratify the risk of transient postoperative hypocalcemia according to patients’ preoperative 25-hydroxyvitaminD status.
Residual-stress relaxation mechanism and model description of 5052H32 Al alloy spun ellipsoidal heads during annealing treatment
Authors: Lin Yong-Cheng , Zhu Jiang-Shan , Chen Jia-Yang , Wang Jun-Quan 
Published: September 2021

AbstractMarginal-restraint mandrel-free spinning is an advanced technology for manufacturing ellipsoidal heads with large diameter-thickness ratios. Nevertheless, the spinning-induced residual stress, which greatly influences the in-service performance of spun heads, should be removed. In this study, the effects of annealing on the residual-stress relaxation behavior of 5052H32 aluminum alloy spun heads were investigated. It is found that the residual stress first rapidly decreases and then remains steady with the increase in annealing time at the tested annealing temperatures. The relaxation of the residual stress becomes increasingly obvious with the increase in annealing temperature. When the annealing temperature is less than 220 °C, there are no obvious changes in grain size. Moreover, the spinning-induced dislocations are consumed by the static recovery behavior, which decreases the residual stress during annealing. When the annealing temperature is approximately 300 °C, the broken grains transform into equiaxed grains. In addition, static recrystallization and recovery behaviors occur simultaneously to promote the relaxation of the residual stress. Considering the different stress relaxation mechanisms, a model based on the Zener-Wert-Avrami equation was established to predict the residual-stress relaxation behavior. Finally, the optimized annealing temperature and time were approximately 300 °C and 30 min, respectively.
MOF-Derived ZnS Nanodots/Ti3C2Tx MXene Hybrids Boosting Superior Lithium Storage Performance
Authors: Cao Bin , Liu Huan , Zhang Xin , Zhang Peng , Zhu Qizhen , Du Huiling , Wang Lianli , Zhang Rupeng , Xu Bin 
Published: September 2021

AbstractZnS has great potentials as an anode for lithium storage because of its high theoretical capacity and resource abundance; however, the large volume expansion accompanied with structural collapse and low conductivity of ZnS cause severe capacity fading and inferior rate capability during lithium storage. Herein, 0D-2D ZnS nanodots/Ti3C2Tx MXene hybrids are prepared by anchoring ZnS nanodots on Ti3C2Tx MXene nanosheets through coordination modulation between MXene and MOF precursor (ZIF-8) followed with sulfidation. The MXene substrate coupled with the ZnS nanodots can synergistically accommodate volume variation of ZnS over charge–discharge to realize stable cyclability. As revealed by XPS characterizations and DFT calculations, the strong interfacial interaction between ZnS nanodots and MXene nanosheets can boost fast electron/lithium-ion transfer to achieve excellent electrochemical activity and kinetics for lithium storage. Thereby, the as-prepared ZnS nanodots/MXene hybrid exhibits a high capacity of 726.8 mAh g−1 at 30 mA g−1, superior cyclic stability (462.8 mAh g−1 after 1000 cycles at 0.5 A g−1), and excellent rate performance. The present results provide new insights into the understanding of the lithium storage mechanism of ZnS and the revealing of the effects of interfacial interaction on lithium storage performance enhancement.
Archaeoseismological study of the Cherichira aqueduct bridge, Kairouan, Tunisia
Authors: Hinzen Klaus-G. , Meghraoui Mustapha , Bahrouni Nejib , Houla Yassine , Reamer Sharon K. 
Published: September 2021

AbstractIn the past, several destructive earthquakes have occurred in the North African Atlas Mountain ranges located along the Africa–Eurasia plate boundary. Although the region is rich with impressive archaeological sites, including those in modern Tunisia, few comprehensive archaeoseismological studies have been conducted. Historic sources account at least three damaging earthquakes in the Kairouan area in central Tunisia between AD 859 and 1041. Little is known about which faults triggered these earthquakes or the size of these events. The water supply of the city of Kairouan depended on a 32-km-long aqueduct with a large bridge (now partially collapsed) at the confluence of the de Mouta and Cherichira rivers. The original bridge of Roman construction was retrofitted twice during the Aghlabid period (AD 800–903) and probably in AD 995 during the Fatimid period. The ruined section of the bridge shows damage which might be related to the AD 859 earthquake shaking. Here, we present a detailed study of the history, the status and the damage of the Cherichira aqueduct bridge using previous historic accounts and written works, a 3D laser scan model, local geological and seismological characteristics, and include results of radiocarbon dating and a timeline of events. In addition to earthquake ground motions, we consider severe flash floods on the bridge as a potential cause of the damage. We estimate the severity of such flash floods and develop a model with 18 earthquake scenarios on local reverse and strike-slip faults with magnitudes between MW6.1 and 7.2. While a few damage patterns might be indicative of flooding, most damage can be attributed to earthquakes. It is highly probable that the earthquake in AD 859 caused enough damage to the Aghlabid bridge to render it dysfunctional; however, to resolve the question of whether another earthquake in AD 911 or 1041 caused the complete destruction of the previously retrofitted aqueduct by the Fatimids requires dating of additional sections of the bridge.
Robust flocking for non-identical second-order nonlinear multi-agent systems
Authors: Li Xiuxian , Su Housheng , Li Li 
Published: September 2021

AbstractThis paper investigates the robust flocking problem for second-order nonlinear systems with a leader and external disturbances. In contrast with most of second-order systems in the literature, the intrinsic dynamics here are nonlinear and non-identical that depend not only on the velocity but also on the position, which is more realistic. Moreover, the interaction topology is undirected and switching. Provided that the leader’s velocity may be constant or time-varying, two distributed flocking control laws have been proposed for two cases to make the differences of the velocities between all followers and the leader approach to zero asymptotically. The proposed distributed flocking control laws are both model-independent which results in the effectiveness of the controllers to cope with the different intrinsic dynamics of the followers and the leader under some assumptions on boundedness of several states. An example is given to illustrate the validity of the theoretical results.
Emerging geo-data sources to reveal human mobility dynamics during COVID-19 pandemic: opportunities and challenges
Authors: Li Xiao , Xu Haowen , Huang Xiao , Guo Chenxiao , Kang Yuhao , Ye Xinyue 
Published: September 2021

AbstractEffectively monitoring the dynamics of human mobility is of great importance in urban management, especially during the COVID-19 pandemic. Traditionally, the human mobility data is collected by roadside sensors, which have limited spatial coverage and are insufficient in large-scale studies. With the maturing of mobile sensing and Internet of Things (IoT) technologies, various crowdsourced data sources are emerging, paving the way for monitoring and characterizing human mobility during the pandemic. This paper presents the authors’ opinions on three types of emerging mobility data sources, including mobile device data, social media data, and connected vehicle data. We first introduce each data source’s main features and summarize their current applications within the context of tracking mobility dynamics during the COVID-19 pandemic. Then, we discuss the challenges associated with using these data sources. Based on the authors’ research experience, we argue that data uncertainty, big data processing problems, data privacy, and theory-guided data analytics are the most common challenges in using these emerging mobility data sources. Last, we share experiences and opinions on potential solutions to address these challenges and possible research directions associated with acquiring, discovering, managing, and analyzing big mobility data.
Exploring the Process of Business Ecosystem Emergence from Value Chains: Insights from the Chinese Mobile Phone Industry
Authors: Shi Xianwei , Luo Yuankun , Hou Hong , Rong Ke , Shi Yongjiang 
Published: September 2021

ABSTRACTA business ecosystem is a community of multiple co-evolving actors with interdependent product offerings organized around a specific value proposition. While the extant literature focuses on these two structural elements of ecosystems that existed ex ante, we challenge this notion with our core discovery that ecosystem actors emerge in an ex post dynamic process. With a longitudinal qualitative study of the vertically disintegrated part of the Chinese mobile phone industry, we develop a two-dimensional process model of ecosystem emergence, namely the temporal dimension that delineates three processal stages of ecosystem emergence and the spatial dimension that highlights an architectural pattern of reciprocities between value chain and resource pool to enable the ecosystem emergence. We also offer inter-temporal enabling conditions during ecosystem evolution. These findings enable us to complement the ecosystem literature by elaborating the antecedents, outcomes, and enabling conditions of ecosystem emergence in relation to multiple types of ecosystem actors. We also shed light on the value chain (re-)configuring process which derives from the reciprocity between value chains and ecosystem resources.
Changing Water Resources Under El Niño, Climate Change, and Growing Water Demands in Seasonally Dry Tropical Watersheds
Authors: Hund Silja V. , Grossmann Iris , Steyn Douw G. , Allen Diana M. , Johnson Mark S. 
Published: September 2021

AbstractThe wet‐dry tropics of Central America are characterized by long dry seasons, during which communities often struggle for water. High interannual rainfall variability, driven in parts by the El Niño Southern Oscillation (ENSO), increases these challenges. Further, climate change projections indicate that the region will likely become drier. However, research on impacts on water resources at the watershed scale is limited in the region—yet this information is essential for water managers. Therefore, in this research, we quantified the potential impacts of ENSO and four different climate change scenarios on water resources in two watersheds in the wet‐dry tropics of Guanacaste, Costa Rica, using a hydrological model (Water Evaluation and Planning Tool [WEAP]). Given that the watersheds are human used, we also explored different water demand scenarios. Modeling results indicated that an extreme El Niño can reduce groundwater recharge and streamflow by ∼60% relative to ENSO neutral. For 2075–2100, modeling results indicated that while potential evapotranspiration increases, actual evapotranspiration decreases due to limited water availability. Further, climate change may lead to reductions of mean annual streamflow and groundwater recharge by 40%–45% and 26%–28%, respectively, in comparison to the historical baseline. Importantly, high population growth could further hasten potentially irreversible groundwater storage declines. On the other hand, reduction of per‐capita water demand could slow down, or even reverse, the decline of groundwater storage.
Micromagnetic Tomography for Paleomagnetism and Rock‐Magnetism
Authors: de Groot Lennart V. , Fabian Karl , Béguin Annemarieke , Kosters Martha E. , Cortés‐Ortuño David , Fu Roger R. , Jansen Chloë M. L. , Harrison Richard J. , van Leeuwen Tristan , Barnhoorn Auke 
Published: September 2021

AbstractOur understanding of the past behavior of the geomagnetic field arises from magnetic signals stored in geological materials, e.g., (volcanic) rocks. Bulk rock samples, however, often contain magnetic grains that differ in chemistry, size, and shape; some of them record the Earth's magnetic field well, others are unreliable. The presence of a small amount of adverse behaved magnetic grains in a sample may already obscure important information on the past state of the geomagnetic field. Recently it was shown that it is possible to determine magnetizations of individual grains in a sample by combining X‐ray computed tomography and magnetic surface scanning measurements. Here we establish this new Micromagnetic Tomography (MMT) technique and make it suitable for use with different magnetic scanning techniques, and for both synthetic and natural samples. We acquired reliable magnetic directions by selecting subsets of grains in a synthetic sample, and we obtained rock‐magnetic information of individual grains in a volcanic sample. This illustrates that MMT opens up entirely new venues of paleomagnetic and rock‐magnetic research. MMT's unique ability to determine the magnetization of individual grains in a nondestructive way allows for a systematic analysis of how geological materials record and retain information on the past state of the Earth's magnetic field. Moreover, by interpreting only the contributions of known magnetically well‐behaved grains in a sample, MMT has the potential to unlock paleomagnetic information from even the most complex, crucial, or valuable recorders that current methods are unable to recover.
Study on Dominant Parameters Determining Streamer Initiation From Hydrometeors in Thundercloud Fields
Authors: Hu Jinjin , Ma Yikai , Gao Xin , Liu Ningyu 
Published: September 2021

AbstractThis study reports a study trying to find the dominant factor on streamer initiation from an isolated hydrometeor in thundercloud fields at 7 km altitude corresponding to an atmosphere pressure of about 0.453 atm. Three parameters are considered including hydrometeor size, shape, and electric quantity. The simulation results indicate that a larger hydrometeor is more likely to initiate a streamer discharge at a lower ambient field for noncharged hydrometeors. The charge on hydrometeor plays a prominent role when a charged hydrometeor has a smaller size, and it is easier to initiate a streamer in this case. At 0.25 Ek, a positive streamer discharge has been presented for a charged hydrometeor with a radius of 0.5 mm. The critical field to form streamer discharge for a column shape hydrometeor without charge is much smaller than that for a spherical hydrometeor. If smaller hydrometeors are charged, the critical field for a spherical hydrometeor becomes lower than that for a column one. The electric quantity charged on hydrometeor has little effect on the critical field for both spherical and column hydrometeors, when the hydrometeor size is larger enough. The charge on hydrometeor plays a dominant role in streamer initiation when hydrometeor is smaller, but hydrometeor shape becomes more important for larger hydrometeor. Streamer discharge can be predicted by Meek number, but stable streamer cannot be ensured. Streamer branch will be met when ambient field is lower than 0.25 Ek.
N2O Is an Important Piece of the Puzzle, but Seeing the Whole Picture Strengthens Denitrification Research
Authors: Emmett B. D. 
Published: September 2021

AbstractFor decades, denitrification research has been limited by the challenge of measuring fluxes of N2 against a background of high atmospheric concentrations. The methods developed to overcome this challenge all have strengths and weaknesses. Weitzman et al. (2021, https://doi.org/10.1029/2020JG006234) demonstrate the potential of one technique, the Nitrogen‐Free Air Recirculation Method, to measure denitrification end‐products in relatively undisturbed soil cores. This work reinforces the importance of N2 as the primary end‐product of denitrification, accounting for over 86% of measured fluxes in all cores sampled, and reveals unforeseen hotspots of denitrification at depth in soil. These findings are consistent with a similar effort to improve estimates of N2O: N2O + N2 yield at the field scale that predicts N2 fluxes two to three times higher than predicted using previous estimates. By providing a more complete picture of N2O and N2 production in terrestrial systems, these efforts can strengthen denitrification research and support essential refinement of ecosystem models. The identification of unforeseen denitrification hotspots highlights the continued surprises of soil nitrogen cycle and should inspire mechanistic research into the biophysical drivers and communities that mediate denitrification hotspots.
A monolithic InP/SOI platform for integrated photonics
Authors: Yan Zhao , Han Yu , Lin Liying , Xue Ying , Ma Chao , Ng Wai Kit , Wong Kam Sing , Lau Kei May 
Published: September 2021

AbstractThe deployment of photonic integrated circuits (PICs) necessitates an integration platform that is scalable, high-throughput, cost-effective, and power-efficient. Here we present a monolithic InP on SOI platform to synergize the advantages of two mainstream photonic integration platforms: Si photonics and InP photonics. This monolithic InP/SOI platform is realized through the selective growth of both InP sub-micron wires and large dimension InP membranes on industry-standard (001)-oriented silicon-on-insulator (SOI) wafers. The epitaxial InP is in-plane, dislocation-free, site-controlled, intimately positioned with the Si device layer, and placed right on top of the buried oxide layer to form “InP-on-insulator”. These attributes allow for the realization of various photonic functionalities using the epitaxial InP, with efficient light interfacing between the III–V devices and the Si-based waveguides. We exemplify the potential of this InP/SOI platform for integrated photonics through the demonstration of lasers with different cavity designs including subwavelength wires, square cavities, and micro-disks. Our results here mark a critical step forward towards fully-integrated Si-based PICs.
Multiferroic oxide BFCNT/BFCO heterojunction black silicon photovoltaic devices
Authors: Guo Kaixin , Wang Xu , Zhang Rongfen , Fu Zhao , Zhang Liangyu , Ma Guobin , Deng Chaoyong 
Published: September 2021

AbstractMultiferroics are being studied increasingly in applications of photovoltaic devices for the carrier separation driven by polarization and magnetization. In this work, textured black silicon photovoltaic devices are fabricated with Bi6Fe1.6Co0.2Ni0.2Ti3O18/Bi2FeCrO6 (BFCNT/BFCO) multiferroic heterojunction as an absorber and graphene as an anode. The structural and optical analyses showed that the bandgap of Aurivillius-typed BFCNT and double perovskite BFCO are 1.62 ± 0.04 eV and 1.74 ± 0.04 eV respectively, meeting the requirements for the active layer in solar cells. Under the simulated AM 1.5 G illumination, the black silicon photovoltaic devices delivered a photoconversion efficiency (η) of 3.9% with open-circuit voltage (Voc), short-circuit current density (Jsc), and fill factor (FF) of 0.75 V, 10.8 mA cm−2, and 48.3%, respectively. Analyses of modulation of an applied electric and magnetic field on the photovoltaic properties revealed that both polarization and magnetization of multiferroics play an important role in tuning the built-in electric field and the transport mechanisms of charge carriers, thus providing a new idea for the design of future high-performance multiferroic oxide photovoltaic devices.
The zinc-finger bearing xenogeneic silencer MucR in α-proteobacteria balances adaptation and regulatory integrity
Authors: Jiao Jian , Zhang Biliang , Li Meng-Lin , Zhang Ziding , Tian Chang-Fu 
Published: September 2021

Abstract
Foreign AT-rich genes drive bacterial adaptation to new niches while challenging the existing regulation network. Here we report that MucR, a conserved regulator in α-proteobacteria, balances adaptation and regulatory integrity in Sinorhizobium fredii, a facultative microsymbiont of legumes. Chromatin immunoprecipitation sequencing coupled with transcriptomic data reveal that average transcription levels of both target and non-target genes, under free-living and symbiotic conditions, increase with their conservation levels. Targets involved in environmental adaptation and symbiosis belong to genus or species core and can be repressed or activated by MucR in a condition-dependent manner, implying regulatory integrations. However, most targets are enriched in strain-specific genes of lower expression levels and higher AT%. Within each conservation levels, targets have higher AT% and average transcription levels than non-target genes and can be further up-regulated in the mucR mutant. This is consistent with higher AT% of spacers between −35 and −10 elements of promoters for target genes, which enhances transcription. The MucR recruitment level linearly increases with AT% and the number of a flexible pattern (with periodic repeats of Ts) of target sequences. Collectively, MucR directly represses AT-rich foreign genes with predisposed high transcription potential while progressive erosions of its target sites facilitate regulatory integrations of foreign genes.
Radial excited heavy mesons *
Authors: Chen Muyang 
Published: September 2021

Abstract
In this study, the first radial excited heavy pseudoscalar and vector mesons (

,

,

,

,

, and

) are investigated using the Dyson-Schwinger equation and Bethe-Salpeter equation approach. It is shown that the effective interactions of the radial excited states are harder than those of the ground states. With the interaction well determined by fitting the masses and leptonic decay constants of

and

, the first radial excited heavy mesons could be quantitatively described in the rainbow ladder approximation. The masses and leptonic decay constants of

,

,

, and

are predicted.