bluuebunny/crossref_metadata_2025_split huggingface dataset:
Validation of ICON‐MIGHTI Thermospheric Wind Observations: 2. Green‐Line Comparisons to Specular Meteor Radars
Authors: Harding Brian J. , Chau Jorge L. , He Maosheng , Englert Christoph R. , Harlander John M. , Marr Kenneth D. , Makela Jonathan J. , Clahsen Matthias , Li Guozhu , Ratnam M. Venkat , Bhaskar Rao S. Vijaya , Wu Yen‐Jung J. , England Scott L. , Immel Thomas J. 
Published: February 2021

AbstractWe compare coincident thermospheric neutral wind observations made by the Michelson Interferometer for Global High‐Resolution Thermospheric Imaging (MIGHTI) on the Ionospheric Connection Explorer (ICON) spacecraft, and four ground‐based specular meteor radars (SMRs). Using the green‐line MIGHTI channel, we analyze 1158 coincidences between Dec 2019 and May 2020 in the altitude range from 94 to 104 km where the observations overlap. We find that the two datasets are strongly correlated (r = 0.82) with a small mean difference (4.5 m/s). Although this agreement is good, an analysis of known error sources (e.g., shot noise, calibration errors, and analysis assumptions) can only account for about a quarter of the disagreement variance. The unexplained variance is 27.8% of the total signal variance and could be caused by unknown errors. However, based on an analysis of the spatial and temporal averaging of the two measurement modalities, we suggest that some of the disagreement is likely caused by temporal variability of the wind on scales ≲70 min. The observed magnitudes agree well during the night, but during the day, MIGHTI observes 16%–25% faster winds than the SMRs. This remains unresolved but is similar in certain ways to previous SMR‐satellite comparisons.
Health-based evaluation of ambient air measurements of PM2.5 and volatile organic compounds near a Marcellus Shale unconventional natural gas well pad site and a school campus
Authors: Long Christopher M. , Briggs Nicole L. , Cochran Brian A. , Mims Destiny M. 
Published: February 2021

Abstract
Background
Limited air monitoring studies with long-term measurements during all phases of development and production of natural gas and natural gas liquids have been conducted in close proximity to unconventional natural gas well pads.

Objective
Conducted in an area of Washington County, Pennsylvania, with extensive Marcellus Shale development, this study investigated whether operations at an unconventional natural gas well pad may contribute to ambient air concentrations of potential health concern at a nearby school campus.

Methods
Almost 2 years of air monitoring for fine particulate matter (PM2.5) and volatile organic compounds (VOCs) was performed at three locations between 1000 and 2800 feet from the study well pad from December 2016 to October 2018. PM2.5 was measured continuously at one of the three sites using a beta attenuation monitor, while 24-h stainless steel canister samples were collected every 6 days at all sites for analysis of 58 VOCs.

Results
Mean PM2.5 concentrations measured during the different well activity periods ranged from 5.4 to 9.5 μg/m3, with similar levels and temporal changes as PM2.5 concentrations measured at a regional background location. The majority of VOCs were either detected infrequently or not at all, with measurements for a limited number of VOCs indicating the well pad to be a source of small and transient contributions.

Significance
All measurement data of PM2.5 and 58 VOCs, which reflect the cumulative contributions of emissions from the study well pad and other local/regional air pollutant sources (e.g., other well pads), were below health-based air comparison values, and thus do not provide evidence of either 24-hour or long-term air quality impacts of potential health concern at the school.
Climate change alters temporal dynamics of alpine soil microbial functioning and biogeochemical cycling via earlier snowmelt
Authors: Broadbent Arthur A D , Snell Helen S K , Michas Antonios , Pritchard William J , Newbold Lindsay , Cordero Irene , Goodall Tim , Schallhart Nikolaus , Kaufmann Ruediger , Griffiths Robert I , Schloter Michael , Bahn Michael , Bardgett Richard D 
Published: February 2021

Abstract
Soil microbial communities regulate global biogeochemical cycles and respond rapidly to changing environmental conditions. However, understanding how soil microbial communities respond to climate change, and how this influences biogeochemical cycles, remains a major challenge. This is especially pertinent in alpine regions where climate change is taking place at double the rate of the global average, with large reductions in snow cover and earlier spring snowmelt expected as a consequence. Here, we show that spring snowmelt triggers an abrupt transition in the composition of soil microbial communities of alpine grassland that is closely linked to shifts in soil microbial functioning and biogeochemical pools and fluxes. Further, by experimentally manipulating snow cover we show that this abrupt seasonal transition in wide-ranging microbial and biogeochemical soil properties is advanced by earlier snowmelt. Preceding winter conditions did not change the processes that take place during snowmelt. Our findings emphasise the importance of seasonal dynamics for soil microbial communities and the biogeochemical cycles that they regulate. Moreover, our findings suggest that earlier spring snowmelt due to climate change will have far reaching consequences for microbial communities and nutrient cycling in these globally widespread alpine ecosystems.
Sequence modification in copoly(ester-imide)s: a catalytic/supramolecular approach to the evolution and reading of copolymer sequence information
Authors: Knappert Marcus , Colquhoun Howard M. 
Published: February 2021

AbstractCatalytic ester-interchange reactions, analogous to mutation and recombination, allow new sequence information to be written statistically into poly(ester-imide) chains based on NDI (1,4,5,8-naphthalenetetracarboxylic diimide) units. Thus, both the insertion of the cyclic ester cyclopentadecanolide (“exaltolide”) into an NDI-based homopolymer and quantitative sequence exchange between two different homopoly(ester-imide)s are catalyzed by di-n-butyl tin(IV) oxide. Emerging sequences are identified at the triplet and quintet levels using supramolecular complexation of pyrene-d10 at the NDI residues to amplify the separation of 1H NMR resonances associated with different sequences. In such systems, pyrene is able to act as a “reader molecule” by generating different levels of ring-current shielding from the different patterns of supramolecular binding to all NDI-centered sequences of a given length.
A meet-up of two second messengers: the c-di-AMP receptor DarB controls (p)ppGpp synthesis in Bacillus subtilis
Authors: Krüger Larissa , Herzberg Christina , Wicke Dennis , Bähre Heike , Heidemann Jana L. , Dickmanns Achim , Schmitt Kerstin , Ficner Ralf , Stülke Jörg 
Published: February 2021

AbstractMany bacteria use cyclic di-AMP as a second messenger to control potassium and osmotic homeostasis. In Bacillus subtilis, several c-di-AMP binding proteins and RNA molecules have been identified. Most of these targets play a role in controlling potassium uptake and export. In addition, c-di-AMP binds to two conserved target proteins of unknown function, DarA and DarB, that exclusively consist of the c-di-AMP binding domain. Here, we investigate the function of the c-di-AMP-binding protein DarB in B. subtilis, which consists of two cystathionine-beta synthase (CBS) domains. We use an unbiased search for DarB interaction partners and identify the (p)ppGpp synthetase/hydrolase Rel as a major interaction partner of DarB. (p)ppGpp is another second messenger that is formed upon amino acid starvation and under other stress conditions to stop translation and active metabolism. The interaction between DarB and Rel only takes place if the bacteria grow at very low potassium concentrations and intracellular levels of c-di-AMP are low. We show that c-di-AMP inhibits the binding of DarB to Rel and the DarB–Rel interaction results in the Rel-dependent accumulation of pppGpp. These results link potassium and c-di-AMP signaling to the stringent response and thus to the global control of cellular physiology.
Near-surface softening and healing in eastern Honshu associated with the 2011 magnitude-9 Tohoku-Oki Earthquake
Authors: Wang Su-Yang , Zhuang Hai-Yang , Zhang Hao , He Hong-Jun , Jiang Wei-Ping , Yao Er-Lei , Ruan Bin , Wu Yong-Xin , Miao Yu 
Published: February 2021

AbstractThe near-surface part of the crust, also called the skin of the earth, is the arena of human activity of which the stiffness is of great concern to engineers in infrastructure construction. The stiffness reduction of near-surface geomaterials also plays a vital role in geohazards triggering. However, the physical mechanism behind the material softening is still not fully understood. Here, we report a coseismic shear-wave velocity reduction in the near surface by up to a few tens of percent during the strongest shaking from the 11 March 2011 Tohoku-Oki Earthquake and a subsequent two-stage healing process including a rapid recovery within a few minutes and a slow recovery over many years. We also present a theoretical contact model between mineral grains in geomaterials containing multiple metastable contacts at small separations due to the oscillatory hydration interaction, which can explain the emergence of different stages in the healing process.
Interfacial engineering of Bi2S3/Ti3C2Tx MXene based on work function for rapid photo-excited bacteria-killing
Authors: Li Jianfang , Li Zhaoyang , Liu Xiangmei , Li Changyi , Zheng Yufeng , Yeung Kelvin Wai Kwok , Cui Zhenduo , Liang Yanqin , Zhu Shengli , Hu Wenbin , Qi Yajun , Zhang Tianjin , Wang Xianbao , Wu Shuilin 
Published: February 2021

AbstractIn view of increasing drug resistance, ecofriendly photoelectrical materials are promising alternatives to antibiotics. Here we design an interfacial Schottky junction of Bi2S3/Ti3C2Tx resulting from the contact potential difference between Ti3C2Tx and Bi2S3. The different work functions induce the formation of a local electrophilic/nucleophilic region. The self-driven charge transfer across the interface increases the local electron density on Ti3C2Tx. The formed Schottky barrier inhibits the backflow of electrons and boosts the charge transfer and separation. The photocatalytic activity of Bi2S3/Ti3C2Tx intensively improved the amount of reactive oxygen species under 808 nm near-infrared radiation. They kill 99.86% of Staphylococcus aureus and 99.92% of Escherichia coli with the assistance of hyperthermia within 10 min. We propose the theory of interfacial engineering based on work function and accordingly design the ecofriendly photoresponsive Schottky junction using two kinds of components with different work functions to effectively eradicate bacterial infection.
Dysregulation of REV-ERBα impairs GABAergic function and promotes epileptic seizures in preclinical models
Authors: Zhang Tianpeng , Yu Fangjun , Xu Haiman , Chen Min , Chen Xun , Guo Lianxia , Zhou Cui , Xu Yuting , Wang Fei , Yu Jiandong , Wu Baojian 
Published: February 2021

AbstractTo design potentially more effective therapies, we need to further understand the mechanisms underlying epilepsy. Here, we uncover the role of Rev-erbα in circadian regulation of epileptic seizures. We first show up-regulation of REV-ERBα/Rev-erbα in brain tissues from patients with epilepsy and a mouse model. Ablation or pharmacological modulation of Rev-erbα in mice decreases the susceptibility to acute and chronic seizures, and abolishes diurnal rhythmicity in seizure severity, whereas activation of Rev-erbα increases the animal susceptibility. Rev-erbα ablation or antagonism also leads to prolonged spontaneous inhibitory postsynaptic currents and elevated frequency in the mouse hippocampus, indicating enhanced GABAergic signaling. We also identify the transporters Slc6a1 and Slc6a11 as regulators of Rev-erbα-mediated clearance of GABA. Mechanistically, Rev-erbα promotes the expressions of Slc6a1 and Slc6a11 through transcriptional repression of E4bp4. Our findings propose Rev-erbα as a regulator of synaptic function at the crosstalk between pathways regulating the circadian clock and epilepsy.
Quantification of Actaea racemosa L. (black cohosh) from some of its potential adulterants using qPCR and dPCR methods
Authors: Shanmughanandhan Jeevitha , Shanmughanandhan Dhivya , Ragupathy Subramanyam , Henry Thomas A. , Newmaster Steven G. 
Published: February 2021

AbstractThe demand for popular natural health products (NHPs) such as Black Cohosh is increasing considerably, which in turn challenges quality assurance (QA) throughout the supply chain. To detect and quantify the target species present in a given NHP, DNA-based molecular techniques such as Real-time quantitative PCR (qPCR) and digital PCR (dPCR) are standard tools in the food and pathogen testing industries. There is a gap in the literature concerning validated quantitative PCR methods for botanicals that can be utilized for QA and good manufacturing practices. The objective of this study is to develop an efficient quantification method using qPCR and dPCR techniques for the detection and quantification of Actaea racemosa (Black cohosh) NHPs from its potential adulterants. These developed methods are validated for applicability on commercial NHPs. Species-specific hydrolysis probe assays were designed to analyze the black cohosh NHPs using qPCR and dPCR techniques. The results confirmed that the developed qPCR and dPCR methods are highly precise for identifying and quantifying black cohosh NHPs, indicating their potential applicability in future routine industrial and laboratory testing. This enables a single qPCR test to determine not only the presence of a specific botanical, but also the amount when mixed with an adulterant.
Predictive values of multiple non-invasive markers for myocardial fibrosis in hypertrophic cardiomyopathy patients with preserved ejection fraction
Authors: Li Yumin , Liu Jia , Cao Yukun , Han Xiaoyu , Shao Guozhu , Zhou Xiaoyue , Gu Jin , Liu Tong , Cui Yue , Shi Heshui 
Published: February 2021

AbstractMyocardial fibrosis assessed by late gadolinium enhancement (LGE) on cardiovascular magnetic resonance (CMR) is associated with cardiovascular outcomes in hypertrophic cardiomyopathy (HCM) patients, but little is known about the utility of non-invasive markers for detecting LGE. This study aims to explore the association between cardiac-specific biomarkers, CMR myocardial strain, left ventricular (LV) hypertrophy and LGE in HCM patients with preserved ejection fraction (EF) and investigate the predictive values of these indexes for LGE. We recruited 33 healthy volunteers and 86 HCM patients with preserved EF to undergo contrast-enhanced CMR examinations. In total, 48 of 86 HCM patients had the presence of LGE. The LGE-positive patients had significant higher serum high-sensitivity cardiac troponin I (hs-cTnI) and N-terminal pro b-type natriuretic peptide (Nt-proBNP) levels and lower global longitudinal (GLS) and circumferential (GCS) strains than the LGE-negative group. The LGE% was independently associated with the Nt-proBNP levels, GCS, LV end-diastolic maximum wall thickness (MWT) and beta-blocker treatment. In the receiver operating characteristic curve analysis, the combined parameters of Nt-proBNP ≥ 108.00 pg/mL and MWT ≥ 17.30 mm had good diagnostic performance for LGE, with a specificity of 81.25% and sensitivity of 70.00%. These data indicate that serum Nt-proBNP is a potential biomarker associated with LGE% and, combined with MWT, were useful for identifying myocardial fibrosis in HCM patients with preserved EF. Additionally, LV GCS may be a more sensitive indicator for reflecting the presence of myocardial fibrosis than GLS.
In situ electron microscopy study of structural transformations in 2D CoSe2
Authors: Gavhane Dnyaneshwar S. , van Gog Heleen , Thombare Balu , Lole Gaurav , Christiaan Post L. , More Mahendra A. , van Huis Marijn A. 
Published: February 2021

AbstractThermally induced structural transformation of 2D materials opens unique avenues for generating other 2D materials by physical methods. Imaging these transitions in real time provides insight into synthesis routes and property tuning. We have used in situ transmission electron microscopy (TEM) to follow thermally induced structural transformations in layered CoSe2. Three transformation processes are observed: orthorhombic to cubic-CoSe2, cubic-CoSe2 to hexagonal-CoSe, and hexagonal to tetragonal-CoSe. In particular, the unit-cell-thick orthorhombic structure of CoSe2 transforms into cubic-CoSe2 via rearrangement of lattice atoms. Cubic-CoSe2 transforms to hexagonal-CoSe at elevated temperatures through the removal of chalcogen atoms. All nanosheets transform to basal-plane-oriented hexagonal 2D CoSe. Finally, the hexagonal to tetragonal transformation in CoSe is a rapid process wherein the layered morphology of hexagonal-CoSe is broken and islands of tetragonal-CoSe are formed. Our results provide nanoscopic insights into the transformation processes of 2D CoSe2 which can be used to generate these intriguing 2D materials and to tune their properties by modifying their structures for electro-catalytic and electronic applications.
A flexible hybrid capacitor based an NiCo2S4 nanowire electrode with an ultrahigh capacitance
Authors: Xia Tong , Liu Ying , Dai Meizhen , Xia Qing , Wu Xiang 
Published: February 2021

In this study, we synthesized NiCo2S4 nanowire bundles on a nickel foam via facile hydrothermal routes. The assembled asymmetric supercapacitor exhibits excellent mechanical stability even at different bending angles.
An energy efficient data gathering scheme for wireless sensor networks using hybrid crow search algorithm
Authors: Kodoth Praveen Kumar , Edachana Govindaraj 
Published: February 2021

AbstractThe most important challenge in Wireless Sensor Networks (WSNs) is to investigate mechanisms for energy‐efficient data gathering. Within the operating range of Wireless Sensor Network (WSN), the sensor nodes are distributed to send the sensed data to the base station. During the transaction of data, some amount of energy is wasted. So, this work is focused on providing an energy‐efficient data gathering scheme by Circular Clustering and Hybrid Crow Search Algorithm for enhancing the lifetime of network. Learning to maximize the lifetime of network and to attain supreme energy efficiency. In the proposed scheme, for robust data gather node selection; initially, the circular cell clusters are accomplished by separating the entire area of the sensor network. Hereafter, to select precise data gathering node in the circular cell cluster region, a multi objective based weighted sum approach is employed for proximity, communication cost, residual energy and coverage. Further, a routing and dynamic mobile sink relocation mechanism are performed to gather data form cluster head using hybrid crow search algorithm (HCSA). Based on the parameters such as total energy consumption, many alive nodes, and network lifetime, the capability of the proposed technique has been investigated. The proposed strategy has better performance analysis when contrasted to the existing techniques.
Flat winding made of aluminum or copper sheet for axial flux machines
Authors: Cakal Gokhan , Keysan Ozan 
Published: February 2021

AbstractA novel flat winding topology has been proposed as an alternative to conventional windings with stranded round wires and other bar wound windings. The proposed winding is manufactured from thin conductor sheets by industrial tools such as stamping press, laser cutter, or water jet. As these tools are widely used in the production of electric machines, the flat winding topology can provide ease of manufacturing without significant modification to the production line. Besides, superior current ratings, shortened end windings, and high fill factors are other advantages of flat winding. Its performance is measured by comparison study between flat wired prototype machine and the stranded wired machines with similar ratings presented in the literature. The proposed winding is implemented on an axial flux permanent magnet machine. Analytical modeling is presented, including field modeling, voltage, torque derivations, and loss modeling. Then, experimental verification of a 1.4‐kW and 26‐Nm prototype with copper and aluminum flat windings is presented, and the performances of two are compared.
Torsional vibration analysis of the surface‐mounted permanent magnet synchronous machine using analytical model considering flux harmonics
Authors: Ren Jie , Zhao Wenliang , Wang Xiuhe , Xing Zezhi 
Published: February 2021

AbstractThe torsional vibration of the surface‐mounted permanent magnet synchronous machine (SPMSM) caused by torque ripple is analysed herein. First, an improved mathematic model of the SPMSM accounting for torsional vibration effect is proposed, which is composed of the voltage equation and motion equation. The voltage equation is established in abc coordinate taking flux harmonics into account, whereas the motion equation is derived based on a simplified two‐mass mechanical model. The perfect precision of the established model is verified by the finite element method (FEM) and experimental results. Then, an analytical method for analysing the machine steady‐state and dynamic torsional vibration response is used based on the proposed mathematic model. The torsional vibrations of a 6p/36s SPMSM under several conditions are analysed and compared. It is shown that the resonance caused by the 12‐th‐order torque harmonic may occur during the start‐up process. Furthermore, the operational speed range of the machine can be extended by suitably decreasing the stiffness coefficient.
Optimising protein synthesis in cell‐free systems, a review
Authors: Batista Angelo C. , Soudier Paul , Kushwaha Manish , Faulon Jean‐Loup 
Published: February 2021

AbstractOver the last decades, cell‐free systems have been extensively used for in vitro protein expression. A vast range of protocols and cellular sources varying from prokaryotes and eukaryotes are now available for cell‐free technology. However, exploiting the maximum capacity of cell free systems is not achieved by using traditional protocols. Here, what are the strategies and choices one can apply to optimise cell‐free protein synthesis have been reviewed. These strategies provide robust and informative improvements regarding transcription, translation and protein folding which can later be used for the establishment of individual best cell‐free reactions per lysate batch.
Design and development of a cascaded modular multi‐level converter based on current‐fed quadruple‐active bridge converters for grid integration of photovoltaic systems
Authors: Malekjamshidi Zahra , Jafari Mohammad 
Published: February 2021

AbstractThis article proposes a new topology of a cascaded modular multi‐level converter (MMC) based on the current‐fed quadruple active bridge (CFQAB) converters for grid integration of photovoltaic (PV) systems. The MMC topology includes multiple cascaded converter modules in each phase of a three‐phase system. Each individual module is further formed by a PV‐linked CFQAB dc–dc converter to integrate the PV outputs and supply it to a high‐voltage dc (HVDC) bus and further to a cascaded inverter to converter to the ac voltage for the distribution grid. The proposed topology features a wide input voltage range, lower current ripple and smaller size due to the use of CFQAB converter as the building block, which makes it an ideal choice for PV applications. The operation principle of the MMC, converter modules and the control techniques have been presented in detail. A scaled‐down prototype of the topology is implemented to validate the operation of the proposed topology and the control systems.