bluuebunny/crossref_metadata_2025_split huggingface dataset:
Financial time series analysis and forecasting with Hilbert–Huang transform feature generation and machine learning
Authors: Leung Tim , Zhao Theodore 
Published: May 2021

AbstractWe present the method of complementary ensemble empirical mode decomposition and Hilbert–Huang transform (HHT) for analyzing nonstationary financial time series. This noise‐assisted approach decomposes any time series into a number of intrinsic mode functions, along with the corresponding instantaneous amplitudes and instantaneous frequencies. Different combinations of modes allow us to reconstruct the time series using components of different timescales. We then apply Hilbert spectral analysis to define and compute the associated instantaneous energy‐frequency spectrum to illustrate the properties of various timescales embedded in the original time series. Using HHT, we generate a collection of new features and integrate them into machine learning models, such as regression tree ensemble, support vector machine, and long short‐term memory neural network. Using empirical financial data, we compare several HHT‐enhanced machine learning models in terms of forecasting performance.
Exploring Treatment Options for PFAS Removal in Brunswick County, North Carolina
Authors: Dowbiggin Bill , Treadway Jonathan , Nichols John , Walker Glenn 
Published: May 2021

Key TakeawaysBrunswick County Public Utilities evaluated several advanced water treatment alternatives to remove per‐ and polyfluoroalkyl substances (PFAS) and other emerging contaminants.A desktop analysis and pilot study confirmed that low pressure reverse osmosis was the most effective technology for removal of PFAS.Previous expansion plans to meet growing demand were merged with the PFAS project to develop a single design and construction program.
Show Me the Money: WIFIA Success Stories
Authors: Cheng Robert C. , Lindsey Lee , Chamberlain Joni , Sandler Eric , Morales Richard , Kiehl Geoffrey 
Published: May 2021

Key TakeawaysReplacing and repairing water infrastructure in the United States is a critical need, but finding a reasonable way to pay for infrastructure projects is a concern for countless utilities.The Water Infrastructure Finance and Innovation Act, a loan program commonly known as WIFIA, was signed into law in 2014 and has become a popular funding solution that continues to evolve and refine its processes.The profiles of four US utilities demonstrate WIFIA's flexibility in addressing different project financing scenarios.
Isopentenol Utilization Pathway for the Production of Linalool in Escherichia coli Using an Improved Bacterial Linalool/Nerolidol Synthase
Authors: Ferraz Clara A. , Leferink Nicole G. H. , Kosov Iaroslav , Scrutton Nigel S. 
Published: May 2021

AbstractLinalool is a monoterpenoid used as a fragrance ingredient, and is a promising source for alternative fuels. Synthetic biology offers attractive alternative production methods compared to extraction from natural sources and chemical synthesis. Linalool/nerolidol synthase (bLinS) from Streptomyces clavuligerus is a bifunctional enzyme, producing linalool as well as the sesquiterpenoid nerolidol when expressed in engineered Escherichia coli harbouring a precursor terpenoid pathway such as the mevalonate (MVA) pathway. Here we identified two residues important for substrate selection by bLinS, L72 and V214, where the introduction of bulkier residues results in variants with reduced nerolidol formation. Terpenoid production using canonical precursor pathways is usually limited by numerous and highly regulated enzymatic steps. Here we compared the canonical MVA pathway to the non‐canonical isopentenol utilization (IU) pathway to produce linalool using the optimised bLinS variant. The IU pathway uses isoprenol and prenol to produce linalool in only five steps. Adjusting substrate, plasmid system, inducer concentration, and cell strain directs the flux towards monoterpenoids. Our integrated approach, combining enzyme engineering with flux control using the artificial IU pathway, resulted in high purity production of the commercially attractive monoterpenoid linalool, and will guide future efforts towards efficient optimisation of terpenoid production in engineered microbes.
Progress in Multifunctional Metal–Organic Frameworks/Polymer Hybrid Membranes
Authors: Liang Bin , Li Bin , Li Zhiqiang , Chen Banglin 
Published: May 2021

AbstractThe fabrication of state‐of‐the‐art membranes with customized functions and high efficiency is of great significance, but presents challenges. Emerging metal‐organic frameworks (MOFs)/polymer hybrid membranes have provided bright promise as an innovative platform to target multifunctional hybrid materials and devices; this is thanks to their unique properties, which come from three components that are collaboratively enforced. This minireview provides a brief overview of recent progress in the construction of such hybrid membranes, and highlights some of their very important applications in separation, conduction, and sensing.
TIPS‐Ethynylated Naphthodiquinoline and Naphthodiacridine: Novel Diazabisacenes
Authors: Ahrens Lukas , Maier Steffen , Misselwitz Erik , Oeser Thomas , Rominger Frank , Freudenberg Jan , Bunz Uwe H. F. 
Published: May 2021

AbstractThe synthesis of two diazabisacenes is reported. A bisboronated naphthalene was Suzuki‐coupled to substituted ethyl nicotinates, then cyclized by intramolecular Friedel‐Crafts acylation. The resulting diketones were alkynylated and reduced to give the title compounds, bis(TIPS‐ethynyl)‐substituted naphtha[1,8‐gh:5,4‐g′h′]diquinoline and naphtho[1,8‐bc:5,4‐b′c′]diacridine. Nitrogen incorporation stabilizes the bisacenes with respect to oxidation compared to their consanguine nonaza analogs.
A case of corticosteroid‐refractory adult‐onset Still's disease successfully controlled with tocilizumab despite transient neutropenia and thrombocytopenia
Authors: Iwata Jun‐ichi , Yamamura Hitomi , Takano Aiko , Horiuchi Yoshihito 
Published: May 2021

AbstractWe report a case of a 50‐year‐old woman with adult‐onset Still's disease (AOSD). Even after receiving steroid pulse therapy and high‐dose oral corticosteroid medication, the patient's serum ferritin level increased, while the number of neutrophils and platelets decreased. However, fever, erythema, sore throat, and arthralgia ceased. Therefore, we administered intravenous tocilizumab (TCZ). However, neutropenia, thrombocytopenia, and exacerbation of hyperferritinemia occurred after the first TCZ infusion. After the second TCZ infusion, the values returned to normal, and we discontinued prednisolone successfully without any flare‐ups of AOSD. We reviewed case reports describing adverse events after TCZ administration in AOSD patients.
Keratosis pilaris caused by dupilumab for the treatment of bronchial asthma
Authors: Shibata Yuka , Sano Shigetoshi 
Published: May 2021

AbstractHere, we present two patients with bronchial asthma, who developed keratosis pilaris (KP) following treatment with dupilumab, a monoclonal antibody to IL‐4 receptor. Both of them reported pruritic papules in their extremities in 1 months after initiation of dupilumab therapy. The lesions newly developed on the day of every administration of dupilumab at 2‐week interval, however, they tended to resolve over time until the next treatment. A diagnosis of KP was made from clinical and histopathologic findings. Dermoscopic examination revealed keratotic plugs with coiled, curly hairs. We suspected that dupilumab might abruptly impact on growth of vellus hair to generate KP.
Synthesis of2H‐benzo[g]furo/thieno/pyrrolo[2,3‐e]indazolesviaIntramolecular Dehydrogenation Photocyclization
Authors: Zhang Wei , Wang Ping , Zhang Xi , Wang Rui , Wang Tao , Liu Zhicun , Zhang Zunting 
Published: May 2021

Main observation and conclusionA catalyst‐, acid‐ and base‐free, environmental‐friendly method for synthesis of 2H‐benzo[g]furo[2,3‐e]indazoles, 2H‐benzo[g]thieno[2,3‐e]indazoles and 2H‐benzo[g]pyrrolo[2,3‐e]indazolesviaUV light irradiation of 3‐phenyl‐4‐(2‐heteroaryl)pyrazoles (aryl = furanyl, thiophenyl andN‐methylpyrrolyl) in EtOH/H2O at room temperature under argon atmosphere was described. Irradiation of 3‐(2‐hydroxyphenyl)‐4‐(2‐heteroaryl)pyrazoles showed a high chemo‐selectivity to obtain dehydrogenation product 2H‐benzo[g]furo/ thieno/pyrrolo[2,3‐e]indazols‐10‐ol. The mechanism of photocyclization was expounded through the process of 6π‐electroncyclization, [1,5]‐hydrogen shift, pyrazole tautomerism, 1,3‐eneamine tautomerism and evolution of H2.
Visible Light‐Mediated Construction of Sulfonated Dibenzazepines
Authors: Qu Chuan‐Hua , Song Gui‐Ting , Ou Jian‐Hua , Tang Dian‐Yong , Xu Zhi‐Gang , Chen Zhong‐Zhu 
Published: May 2021

Main observation and conclusionA new method to access sulfonated dibenz[b,e]azepines via visible‐light photoredox catalysis is described. Employing inexpensive and commercially available sulfonyl chlorides to form the sulfonyl radicals enables the alkyne addition reaction followed by a 7‐membered radical cyclization step to furnish sulfonated dibenzazepines. In addition, an Ugi‐type multicomponent reaction (MCR) for the synthesis of o‐aminophenylacetylene derivatives can also be used as a rapid substrate synthesis method for the cascade radical cyclization protocol to obtain a series of highly functionalized sulfonylated dibenzazepines, which undoubtedly greatly simplifies the synthetic steps of the dibenzazepine compounds that are important core structures in pharmaceuticals.
Oxidative Photopolymerization of 3,4‐Ethylenedioxythiophene (EDOT) via Graphitic Carbon Nitride: A Modular Toolbox for Attaining PEDOT**
Authors: Esen Cansu , Antonietti Markus , Kumru Baris 
Published: May 2021

AbstractConductive polymers find key applications ranging from optoelectronics and OLEDs to conductive composite materials. The synthesis of conductive polymers from monomers, such as thiophene derivatives, pyrroles and aniline, mainly relies on oxidative polymerization, and the processing of so‐formed (insoluble) polymers is a major issue that needs to be addressed. In the present work, oxidative photopolymerization of 3,4‐ethylenedioxythiophene (EDOT) by visible light employing the metal‐free semiconductor graphitic carbon nitride (g‐CN) is presented. Two main reaction pathways based on g‐CN content are described, and the formation of processable oligo‐EDOT is demonstrated.
Transient dynamics during kelp forest recovery from fishing across multiple trophic levels
Authors: Dunn Robert P. , Samhouri Jameal F. , Baskett Marissa L. 
Published: May 2021

AbstractOutcomes of management efforts to recover or restore populations of harvested species can be highly dependent on environmental and community context. Predator–prey interactions can alter recovery trajectories, and the timing of management actions within multi‐trophic level harvest scenarios may influence the dynamics of recovery and lead to management trade‐offs. Recent work using a generalist predator–prey model suggests that management promoting synchronized recovery of predators and prey leads to faster and less variable recovery trajectories than sequential recovery (predator or prey first). However, more complex communities may require different management actions to minimize recovery time and variability. Here, we use a tri‐trophic level rocky reef community dynamics model with size‐structure and fisheries at multiple trophic levels to investigate the importance of three ecological processes to recovery of fished communities: (1) size‐structured predation, (2) non‐consumptive effects of predators on prey behavior, and (3) varying levels of recruitment. We also test the effects of initiating recovery from community states associated with varying degrees of fishery‐induced degradation and develop a simulation in which the basal resource (kelp) is harvested. In this system, a predator‐first closure generally leads to the least volatile and quickest recovery, whether from a kelp forest, urchin barren, or intermediate community state. The benefits gained by selecting this strategy are magnified when recovering from the degraded community, the urchin barren, because initial conditions in the degraded state lead to lengthy recovery times. However, the shape of the size‐structured predation relationship can strongly affect recovery volatility, where the differences between alternate management strategies are negated with size‐independent predation. External recruitment reduces return times by bolstering the predatory lobster population. These results show that in a tightly linked tri‐trophic level food web with top‐down control, a predator‐first fishery closure can be the most effective strategy to reduce volatility and shorten recovery, particularly when the system is starting from the degraded community state. Given the ubiquity of top predator loss across many ecosystems, we highlight the value of incorporating insights from community ecology into ecosystem management.
Coral monitoring in northwest Australia with environmental DNA metabarcoding using a curated reference database for optimized detection
Authors: Dugal Laurence , Thomas Luke , Wilkinson Shaun P. , Richards Zoe T. , Alexander Jason B. , Adam Arne A.S. , Kennington W. Jason , Jarman Simon , Ryan Nicole M. , Bunce Michael , Gilmour James P. 
Published: May 2021

AbstractThe need for efficient and more accurate ways of monitoring threatened ecosystems is becoming increasingly urgent as climate change intensifies. Coral reefs are an example of an ecosystem in crisis, with widespread declines in coral cover and diversity documented over recent decades. Novel molecular approaches such as biomonitoring using environmental DNA (eDNA) from seawater samples show great potential to complement future coral reef monitoring programs, especially when used in combination with conventional methods. However, eDNA metabarcoding studies often rely on public databases (e.g., GenBank) for assigning taxonomy, which generally limits the number of sequences that can be taxonomically identified. The extent to which building reference tissue sequences improves taxonomic resolution has yet to be fully examined. Here, we combined traditional coral reef monitoring data with eDNA assessments derived from seawater collected at the highly diverse Rowley Shoals in Western Australia. Using two ITS2 assays developed to target basal metazoan DNA and a reference database spiked with 70 local coral specimens, we identified 37 genera and 40 species from 56 1 L seawater samples. We identified considerable overlap of taxa with visual survey data and showed that assignment of amplicon sequence variants was significantly improved when “spiking” the taxonomic classifier with curated sequences of locally collected species. Our findings showcase the potential of eDNA metabarcoding for monitoring the biodiversity of reef corals and highlight the importance of custom reference sequence databases for improving taxonomic resolution in metabarcoding studies.
Two‐dimensional halide perovskite quantum‐well emitters: A critical review
Authors: Wang Kang , Park Jee Yung , Akriti  , Dou Letian 
Published: May 2021

AbstractTwo‐dimensional (2D) halide perovskites can be regarded as natural organic‐inorganic hybrid quantum wells, which exhibit very promising light‐emitting applications due to their high photoluminescence quantum yield, narrow emission bandwidth, and large exciton binding energy. However, it remains a grand challenge to achieve reliable devices for both light‐emitting diodes (LEDs) and lasers utilizing phase‐pure 2D perovskites. Recently, exciting progresses have been made with respect to molecular design, optoelectronic property, and device fabrication for novel 2D perovskite hybrid quantum‐wells. In this article, we critically review the key challenges of exciton losses, charge injections, and triplet issues associated with the light‐emitting applications of such phase‐pure 2D perovskites after examining their recent breakthroughs in LEDs and lasers. Lastly, we provide a new perspective on molecular engineering strategies to address the above‐mentioned fundamental issues, which may open up a new avenue to the development of highly efficient quantum‐well emitters for solid‐state lighting and display.image
Close‐packed storage of potassium metallic clusters achieved through nanostructure engineering of ultrafine hollow nanoparticles‐based carbon nanoclusters
Authors: Liu Bingqiu , Zhang Qi , Li Lu , Zhang Lingyu , Jin Zhanshuang , Wang Chungang , Su Zhongmin 
Published: May 2021

AbstractUltrafine hollow nanoparticles‐based (7 nm) carbon nanoclusters (HNPCNCs) are developed by a facile and novel method. Benefiting from the ultrafine nanostructure, we have achieved close‐packed storage of K metallic clusters and a close‐packed K metallic clusters with a diameter of 7 nm has been observed for the first time through ex TEM. In K‐ion batteries, HNPCNCs anodes deliver an ultrahigh capacity of 269.8 mA h g−1 at 0.5 A g−1 after 200 cycles, outstanding rate performance of 150.5 mA h g−1 after 5000 cycles at 5 A g−1. Moreover, an excellent electrochemical performance has been obtained by HNPCNCs//potassium Prussian blue potassium‐ion full cells, highlighting the practicability of HNPCNCs. The unprecedented electrochemical performance is attributed to the close‐packed K metallic clusters achieved by unique ultrafine hollow nanoparticles in the carbon nanoclusters.image
Bestimmung von Gebirgsspannungen mit dem Überbohrverfahren – Teil 2: Weggebersonden – Neufassung der Empfehlung Nr. 14 des Arbeitskreises „Versuchstechnik Fels“ der DGGT
Authors: Heusermann Stefan , Kiehl Johannes R. 
Published: May 2021

AbstractDer Arbeitskreis AK 3.3 „Versuchstechnik Fels“ der Deutschen Gesellschaft für Geotechnik e. V. erarbeitet Empfehlungen für felsmechanische Labor‐ und Feldversuche sowie Messungen im Gebirge und an geotechnischen Bauwerken. Die vorliegende Neufassung der Empfehlung Nr. 14 behandelt Überbohrversuche zur Bestimmung von Gebirgsspannungen und berücksichtigt die Weiterentwicklung der Versuchstechnik seit der Herausgabe der Empfehlung Nr. 14 „Überbohr‐Entlastungsversuche zur Bestimmung von Gebirgsspannungen“ im Jahre 1990 [1]. Es werden die Anforderungen an die Messgeräte sowie die Vorgehensweise für die Durchführung und Auswertung dieser Versuche festgelegt. Ferner wird auf die Empfehlungen der International Society for Rock Mechanics (ISRM), in denen Überbohrversuche behandelt werden, hingewiesen [2, 3]. Die Empfehlung Nr. 14 ist in zwei Teile gegliedert. Im Teil 1 werden Überbohrversuche mithilfe von Triaxialmesssonden behandelt. Der vorliegende Teil 2 dieser Empfehlung befasst sich mit Überbohrversuchen mittels Weggebersonden.
A learning portal model of emerging markets multinationals
Authors: Hertenstein Peter , Alon Ilan 
Published: May 2021

AbstractResearch SummaryThe purpose of the article is to explain the mechanisms underlying the internationalization springboard strategies of China's emerging multinationals in the automobile industry. Using a unique combination of location bound (country‐specific) and non‐location bound (firm‐specific) advantages, companies in this industry have overcome their latecomer disadvantages by exploring knowledge from mature markets through backward and forward integration of the value chain, and exploiting this knowledge to enhance their competitive position, first at home, then in emerging markets and later in developed countries. We test and refine springboarding theory and propose the learning portal model. The learning portal model can be used as a new theory of emerging markets multinationals beyond China and the automobile industry.Management SummaryThe globalization of Chinese enterprises is upon us. Chinese enterprises have not only successfully internationalized to other emerging markets, but also to advanced economies. To do so, these firms used springboard strategies to leapfrog certain technological development stages and accelerate their catch‐up trajectory with incumbent firms from the advanced economies. This article investigates the catch‐up strategies of China's leading automotive companies. We find that Chinese enterprises establish learning portals in mature markets to acquire knowledge and assets, which they first exploit in their home market, before seeking to expand their market share in other emerging markets and finally advanced economies.
Neural correlates of empathy for babies in postpartum women: A longitudinal study
Authors: Bak Yunjin , Nah Yoonjin , Han Sanghoon , Lee Seung‐Koo , Kim Jiwoong , Shin Na‐Young 
Published: May 2021

AbstractThis study investigated the empathic response of postpartum women to babies in pain and the underlying neural mechanism. Postpartum women responded with more empathy and speed to babies over other stimuli compared to controls. Brain scans taken 3 months after birth showed more elevated activation in the Middle cingulate cortex/middle frontal gyrus (MCC/MFG) than the controls regardless of the task condition. When compared to the adult and neutral conditions, the posterior cingulate cortex (PCC) region was consistently more activated when postpartum women saw babies than controls. In addition, higher activation levels in the PCC region for the baby condition significantly correlated with faster and more empathic responses to babies. Considering that PCC is a core region for the theory of mind or mentalizing which requires cognitive reasoning to understand others, these results suggest that PCC might be a pivotal neural locus facilitating cognitive efforts to empathize with babies during the postpartum period. In a follow‐up experiment at 12 months after birth, we were still able to observe higher activity in the MCC/MFG of postpartum women. However, previously observed PCC activation patterns disappeared 12 months after birth, despite the women's response patterns to babies still being maintained. These results suggest that the mentalizing process activated to empathize with babies in the early postpartum period becomes less cognitively demanding over time.
Greater than 10 cm2 V−1 s−1: A breakthrough of organic semiconductors for field‐effect transistors
Authors: Hu Peng , He Xuexia , Jiang Hui 
Published: May 2021

AbstractOrganic semiconductors have been receiving intensive attention due to the specific advantages of low‐temperature processing ability, low‐fabrication cost, flexibility, and so forth. The charge carrier mobility of higher than 10 cm2 V−1 s−1 for organic semiconductors is of great importance to be studied since it presents a future promising research direction toward commercial microelectronic applications. With the significant progress of the discovery of novel organic molecules and the further improvements of device fabrication technology, some organic molecules can break the limit of our knowledge and show very high mobilities. In this review, organic polymers and small molecules with mobilities above 10 cm2 V−1 s−1 are first introduced to provide the readers with a general understanding of the features and characteristics of high‐performance organic semiconductors. Then, some important parameters, including the molecular structures, the device configurations, and the performance, are discussed in detail. Finally, the clues to obtain high mobility are summarized, and the perspective toward the future possible research directions are also provided.image