bluuebunny/crossref_metadata_2025_split huggingface dataset:
Enantioselective 1,4‐Addition Reaction of α,β‐Unsaturated Carboxylic Acids with Cycloalkanones Using Cooperative Chiral Amine–Boronic Acid Catalysts
Authors: Horibe Takahiro , Hazeyama Takashi , Nakata Yuto , Takeda Kazuki , Ishihara Kazuaki 
Published: June 2020

AbstractAn enantioselective 1,4‐addition of α,β‐unsaturated carboxylic acids with cycloalkanones has been developed by using chiral amine–boronic acid cooperative catalysts. In the presence of a chiral amine and boronic acid, cycloalkanones and carboxylic acids are activated as chiral enamines and mixed anhydrides, respectively. The corresponding 1,4‐adducts are obtained in high yield with high enantioselectivity. Furthermore, subsequent oxylactonization of the 1,4‐adducts gives spirolactones with high diastereoselectivity.
Accelerating Biphasic Biocatalysis through New Process Windows
Authors: Huynh Florence , Tailby Matthew , Finniear Aled , Stephens Kevin , Allemann Rudolf K. , Wirth Thomas 
Published: June 2020

AbstractProcess intensification through continuous flow reactions has increased the production rates of fine chemicals and pharmaceuticals. Catalytic reactions are accelerated through an unconventional and unprecedented use of a high‐performance liquid/liquid counter current chromatography system. Product generation is significantly faster than in traditional batch reactors or in segmented flow systems, which is exemplified through stereoselective phase‐transfer catalyzed reactions. This methodology also enables the intensification of biocatalysis as demonstrated in high yield esterifications and in the sesquiterpene cyclase‐catalyzed synthesis of sesquiterpenes from farnesyl diphosphate as high‐value natural products with applications in medicine, agriculture and the fragrance industry. Product release in sesquiterpene synthases is rate limiting due to the hydrophobic nature of sesquiterpenes, but a biphasic system exposed to centrifugal forces allows for highly efficient reactions.
The Sound of Batteries: An Operando Acoustic Emission Study of the LiNiO2 Cathode in Li–Ion Cells
Authors: Schweidler Simon , Bianchini Matteo , Hartmann Pascal , Brezesinski Torsten , Janek Jürgen 
Published: June 2020

AbstractThe development of advanced Li‐ion batteries relies on the implementation of high‐capacity Ni‐rich layered oxide cathode materials, such as NCM and NCA, among others. However, fast performance decay because of intrinsic chemical and structural instabilities hampers their practical application. Hence, thoroughly understanding degradation processes is crucial to overcome current limitations. To monitor instabilities of electrode materials under realistic operating conditions, the application of nondestructive operando techniques is required. While structural changes of crystalline phases can be studied by X‐ray diffraction, microstructural changes (e. g., particle fracture) cannot be easily accessed in situ and are therefore mostly investigated ex situ. Here, we use acoustic emission (AE) measurements to probe a potential next‐generation cathode material in real‐time. Specifically, we focus on LiNiO2 (LNO) and demonstrate that AE events in different frequency ranges can be correlated with the formation of the cathode solid‐electrolyte interphase and the mechanical degradation during electrochemical cycling.
Potassium‐Ion Storage in Cellulose‐Derived Hard Carbon: The Role of Functional Groups
Authors: Nanjundan Ashok Kumar , Gaddam Rohit Ranganathan , Farokh Niaei Amir H. , Annamalai Pratheep K. , Dubal Deepak P. , Martin Darren James , Yamauchi Yusuke , Searles Debra J. , Zhao Xiu Song 
Published: June 2020

AbstractPotassium‐ion storage is being explored by researchers for its advantages in forming graphite‐based intercalation compounds, with cost‐effective production compared to lithium‐ion systems. However, its poor performance in graphite‐based platforms, owing to the volume expansion required for intercalation, has demanded alternative materials for reversible potassiation. Herein, we demonstrate a simple one‐step pyrolysis approach to develop an amorphous hard carbon material from commercial cellulose for high‐performance potassium‐ion batteries (KIB). The larger interlayer spacing (∼0.4 nm) alongside the electronegative oxygen functional groups promotes potassium‐ion storage. High capacity, good rate and long cycling performance with lower‐volume expansion could be credited to the amorphous carbon that possesses turbostratic nanodomains. Further, oxygen functional groups on the carbon material are identified in our experimental studies, and density functional theory simulations indicate that these are likely to enhance the potassium‐ion capacity of the materials.
Ecology Education Goes Four‐Dimensional
Authors: Middendorf George , Mourad Teresa , Johnston Jessica 
Published: June 2020

AbstractSince the Four‐Dimensional Ecology Education (4DEE) framework was endorsed in the fall of 2018 by the ESA Governing Board, activities of the nine‐member 4DEE Subcommittee have focused on developing a self‐assessment rubric, a guide for assessing student learning, support for majors and non‐majors courses, and a comprehensive report. Together, these resources will advance implementation of the 4DEE framework. The subcommittee is also planning to form communities of practice and host online conversations in support of education innovation by all members of the ecological community.
Untersuchungen zur Prüfmethodik bei Dauerschwingversuchen von Betonstahl
Authors: Osterminski Kai , Hiemer Florian 
Published: June 2020

AbstractInfolge dynamischer Belastung von Stahlbetontragwerken (Windenergieanlagen) kann es auch bei Lasten unterhalb der statischen Festigkeit zu Materialermüdung im Betonstahl kommen. Materialseitig wird die dynamische Festigkeit im Dauerschwingversuch geprüft. Neben der Oberflächengeometrie, der chemischen Zusammensetzung hängt das Dauerschwingverhalten auch vom Belastungsregime ab. Im vorliegenden Beitrag wurden theoretische Berechnungen zur verrichteten physikalischen Arbeit während den Dauerschwingversuchen durchgeführt und in einer Parameterstudie für unterschiedliche Lastregime ausgewertet. Vergleichende experimentelle Untersuchungen zeigten, dass die Ergebnisse des Lastregimes mit fixierter Oberspannung zur Prüfung von Betonstahl nicht den theoretischen Berechnungen gleichen. Vor diesem Hintergrund ist zu diskutieren, inwieweit die Rahmenbedingungen des Dauerschwingversuchs die Absicht der Quantifizierung einer realitätsnahen Wöhlerlinie für Betonstahl tatsächlich erlauben.
Design, Synthesis and in Vitro Evaluation of Tylophorine Derivatives as Possible Antitumor Agents
Authors: Mang Zhiguo , Zhang Shuai , Bai Jing , Li Meijuan , Li Hao 
Published: June 2020

AbstractStructural simplification and modification of natural products are always very important resources to antitumor drugs. By introducing various aminomethyl groups and amide groups into the phenanthrene ring of tylophorine, a novel series of tylophorine derivatives have been designed and synthesized, and their antiproliferative activities against MCF‐7, A549 and HepG‐2 cells have been evaluated, too. The results indicated that most of the prepared compounds exhibited good antitumor activities. Especially, one compound with an {ethyl[2‐(morpholin‐4‐yl)ethyl]amino}methyl group at the side chain exhibited the most significant cytotoxic effects.
Characterization of antiapoptotic microRNAs in primary Sjögren's syndrome
Authors: Yang Ying , Hou Yingzi , Li Jinghui , Zhang Fangming , Du Quan 
Published: June 2020

During the development of primary Sjögren's syndrome (pSS), aberrant expression of autoantigen is a hallmark event. To explore the regulation of autoantigen tripartite motif containing 21 (Ro/SSA, TRIM21), microRNA profiling was performed in our previous study. In which, two TRIM21‐targeting microRNAs were identified, namely miR‐1207‐5p and miR‐4695‐3p. To further pursue their roles in the development of pSS, assays were performed with cultured human submandibular gland (HSG) cells, and salivary gland tissues. Results showed that transfection of miR‐1207‐5p or miR‐4695‐3p mimics down‐regulated not only the expression of TRIM21, but also the levels of pro‐apoptotic genes B cell lymphoma 2 associated X (BAX), Caspase 9 (CASP‐9) and Caspase 8 (CASP‐8). This finally led to antiapoptotic phenotypes in HSG cells. Consistent with the antiapoptotic activity, transfection of microRNA inhibitors up‐regulated the expression of TRIM21 and led to a pro‐apoptotic phenotype. These therefore propose miR‐1207‐5p and miR‐4695‐3p as two antiapoptotic microRNAs functioning through apoptosis pathway. Supporting this speculation, assays performed with salivary gland tissues revealed down‐regulation of miR‐1207‐5p and miR‐4695‐3p, as well as up‐regulation of TRIM21 and pro‐apoptotic CASP‐8 gene in pSS samples.Significance of the studyFor pSS patients, apoptosis of acinar and ductal epithelial cells has been proposed to be a potential mechanism that impairs the secretion of salivary glands. In our study, two autoantigen‐targeting microRNAs were characterized as antiapoptotic microRNAs functioning through apoptosis pathway, which may be potential targets for the treatment of pSS.
Case report: Migraine that persisted for over 20 years disappears after treatment for pulmonary arteriovenous fistula
Authors: Kakeshita Kazuyuki , Yoneda Taro , Koba Hayato , Tanimura Kota , Ueda Tsukasa , Kaneda Tomoya , Hara Johsuke , Kasahara Kazuo 
Published: June 2020

AbstractWe presented a rare case of pulmonary arteriovenous fistula in a patient who suffered from migraine with optic aura for longer than 20 years. This case suggests that the migraine could be expected to disappear after treatment for pulmonary arteriovenous fistula.
Metal‐Organic Framework‐Based Catalysts for Oxidative Desulfurization
Authors: Piscopo C. G. , Granadeiro C. M. , Balula S. S. , Bošković D. 
Published: June 2020

AbstractOxidative desulfurization (ODS) is emerging as the most promising methodology to remove refractive naturally occurring sulfides from fossil fuels. Metal‐organic frameworks (MOFs), a fascinating class of materials, are suitable as catalysts for this process due to the theoretical infinite number of combinations of polynuclear metal clusters and organic linkers. A rational fine‐tuning of the material structure, porosity and chemical functionality have given rise to a considerable number of MOF‐based catalytic active materials. Furthermore, MOFs can act as host, with programmable cavity sizes to accommodate catalytic species, forming novel robust catalytic MOF composite materials. Herein an account of this growing field of heterogeneous catalysis is reported and discussed, aiming to point out future outlooks and perspectives.
Building Hierarchical Microcubes Composed of One‐Dimensional CoSe2@Nitrogen‐Doped Carbon for Superior Sodium Ion Batteries
Authors: Liu Tiezhong , Li Youpeng , Hou Shuang , Yang Chenghao , Guo Yayun , Tian Sheng , Zhao Lingzhi 
Published: June 2020

AbstractDesigning and synthesizing highly stable anode materials with high capacity is critical for the practical application of sodium ion batteries (SIBs), however, to date, this remains an insurmountable barrier. The introduction of hierarchical architectures and carbon supports is proving an effective strategy for addressing these challenges. Thus, we have fabricated a hierarchical CoSe2@nitrogen‐doped carbon (CoSe2@NC) microcube composite using the Prussian blue analogue Co3[Co(CN)6]2 as template. The rational combination of the unique hierarchical construction from one to three dimensions and a nitrogen‐doped carbon skeleton facilitates sodium ion and electron transport as well as stabilizing the host structure during repeated discharge/charge processes, which contributes to its excellent sodium storage capability. As expected, the as‐prepared CoSe2@NC composite delivered remarkable reversible capacity and ultralong cycling lifespan even at a high rate of 2.0 A g−1 (384.3 mA h g−1 after1800 loops) when serving as the anode material for SIBs. This work shows the great potential of the CoSe2‐based anode for practical application in SIBs, and the original strategy may be extended to other anode materials.
Phenol Oxidation by a Nickel(III)–Fluoride Complex: Exploring the Influence of the Proton Accepting Ligand in PCET Oxidation
Authors: Mondal Prasenjit , McDonald Aidan R. 
Published: June 2020

AbstractIn order to gain insight into the influence of the H+‐accepting terminal ligand in high‐valent oxidant mediated proton coupled electron transfer (PCET) reactions, the reactivity of a high valent nickel–fluoride complex [NiIII(F)(L)] (2, L=N,N’‐(2,6‐dimethylphenyl)‐2,6‐pyridinecarboxamidate) with substituted phenols was explored. Analysis of kinetic data from these reactions (Evans–Polanyi, Hammett, and Marcus plots, and KIE measurements) and the formed products show that 2 reacted with electron rich phenols through a hydrogen atom transfer (HAT, or concerted PCET) mechanism and with electron poor phenols through a stepwise proton transfer/electron transfer (PT/ET) reaction mechanism. The analogous complexes [NiIII(Z)(L)] (Z=Cl, OCO2H, O2CCH3, ONO2) reacted with all phenols through a HAT mechanism. We explore the reason for a change in mechanism with the highly basic fluoride ligand in 2. Complex 2 was also found to react one to two orders of magnitude faster than the corresponding analogous [NiIII(Z)(L)] complexes. This was ascribed to a high bond dissociation free energy value associated with H−F (135 kcal mol−1), which is postulated to be the product formed from PCET oxidation by 2 and is believed to be the driving force for the reaction. Our findings show that high‐valent metal–fluoride complexes represent a class of highly reactive PCET oxidants.
Triaxially Woven Hydrogen‐Bonded Chicken Wires of a Tetrakis(carboxybiphenyl)ethene
Authors: Suzuki Yuto , Tohnai Norimitsu , Hisaki Ichiro 
Published: June 2020

AbstractInterpenetration of low‐dimensional networked structural motifs crucially affects porosity, stability, and properties of the whole reticular framework. However, varying and controlling the manner of interpenetration is still challenging. Herein, a porous hydrogen‐bonded organic framework (HOF) with wvm‐like weave constructed by triaxially woven chicken wires of X‐shaped tetra‐armed tetrakis(carboxybiphenyl)ethene CBPE, formally 4′,4′′′,4′′′′′,4′′′′′′′‐(ethene‐1,1,2,2‐tetrayl)tetrakis(1,1′‐biphenyl‐4‐carboxylic acid), is reported. The structure is a contrast to a non‐interpenetrated layered framework composed of tetrakis(4‐carboxyphenyl)ethene CPE. This exotic framework of CBPE is due to the disproportionate conformation of the outer four phenylene rings in the peripheral biphenyl arms. The activated framework CBPE‐1a exhibits thermal stability up to 220 °C and a BET surface area of 555 m2 g−1. Additionally, the HOF shows mechanochromic behavior in terms of fluorescence color and quantum efficiency. The achievement of the present HOFs can provide insight into constructing a new type of functional porous organic materials with interwoven network structures.
Waste Separation in Primary Education – A Pre‐Post Design Study to Capture Students' Awareness of Recycling with Cartoons
Authors: Yılmaz Ayhan , Çelikler Dilek , Aksan Zeynep 
Published: June 2020

AbstractZiel der Studie ist es, die Wirkung des Unterrichts mit wissenschaftlichen Cartoons auf das Wissen über das Recycling von SchülerInnen der dritten und vierten Klasse der Grundschule zu ermitteln. Die Zielgruppe, die erforscht wurde, besteht aus insgesamt 105 SchülerInnen, von denen 56 SchülerInnen die dritte Klasse und 49 SchülerInnen die vierte Klasse einer staatlichen Grundschule in der Türkei besuchen. In der Studie wurden wissenschaftliche Cartoons verwendet, welche von Çelikler, Aksan und Yenikalaycı im Jahr 2017 [1] erstellt wurden. In der Studie wurden drei Aktivitäten durchgeführt. Außerdem wurde festgestellt, dass die SchülerInnen die Recyclingsymbole wahrnehmen und die Verwendung dieser Symbole sich in ihren Zeichnungen steigerte. Auch die Anzahl der Zeichnungen von Recyclingfahrzeugen steigerte sich. Zum Schluss ist zu erwähnen, dass die SchülerInnen mit ihren Zeichnungen interessante Botschaften vermittelten, wie z. B. „Recycling hält die Natur sauber“, „wir wollen eine saubere Umwelt“, „als Kind trage ich zum Recycling bei“, sowie die Botschaft „Papier ist aus Holz – wir sollten es nicht verschwenden“ war sehr interessant.
Supported Cobalt Catalysts for Acceptorless Alcohol Dehydrogenation
Authors: Kaźmierczak Kamila , Pinel Catherine , Loridant Stéphane , Besson Michèle , Michel Carine , Perret Noémie 
Published: June 2020

AbstractThe acceptor‐less dehydrogenation of 2‐octanol was tested over cobalt supported on Al2O3, C, ZnO, ZrO2 and various TiO2 substrates. The catalysts were characterized by ICP, XRD and TGA‐H2. For Co/TiO2 P25, the effects of passivation, aging (storage at room temperature), and in situ activation under H2 were investigated. The catalysts must be tested shortly after synthesis in order to prevent deactivation. Cobalt supported on TiO2 P25 was the most active and 69 % yield of 2‐octanone was obtained, using decane as a solvent. Selectivities for 2‐octanone were observed in the range of 90 % to 99.9 %. Small amounts of C16 compounds were also formed due to aldol condensation/dehydration reactions. The catalysts exhibited higher conversion in the dehydrogenation of secondary alcohols (65‐69 %), in comparison to primary alcohols (2–10 %). The dehydrogenation of 1,2‐octanediol led to 1‐hydroxy‐2‐octanone, with a selectivity of 90 % and 69 % for Co/TiO2 P25 and Co/TiO2 P90, respectively.
Heterogeneous Photocatalysis in Organic Synthesis
Authors: Gisbertz Sebastian , Pieber Bartholomäus 
Published: June 2020

AbstractThe front cover artwork is provided by the group of Dr. Bartholomäus Pieber at the Max Planck Institute of Colloids and Interfaces (Germany). The image symbolizes the activation of a heterogeneous photocatalyst by visible light and its application for organic synthesis. Read the full text of the Review at 10.1002/cptc.202000014.
Synthesis and characterization of barbarin, a possible source of unexplained aminorex identifications in forensic science
Authors: Machin Jacob , Childers Taylor , Kudrimoti Sucheta , Eisenberg Rod , Fenger Clara , Hartmann Petra , Maylin George , Shults Theodore , Tobin Thomas 
Published: June 2020

AbstractAminorex is a US DEA Schedule 1 controlled substance occasionally detected in racing horses. A number of aminorex identifications in sport horses were thought to have been caused by exposure to plant sources of aminorex. Glucobarbarin, found in plants of the Brassicaceae family, has been suggested as a potential proximate chemical source by being metabolized in the plant or the horse to aminorex. In Brassicaceae, glucobarbarin is hydrolyzed by myrosinase to yield barbarin, which serves as an insect repellant and/or attractant and is structurally related to aminorex. The synthesis, purification, and characterization of barbarin is now reported for use as a reference standard in aminorex related research concerning equine urinary identifications of aminorex and also for possible use in equine administration experiments. Synthesis of barbarin was performed via ring closure between phenylethanolamine and carbon disulfide in tetrahydrofuran with the catalyst pyridine under reflux. The reaction yielded a white crystalline substance that was purified and chemically characterized as barbarin for use as a Certified Reference Standard or for studies related to equine aminorex identification.
Eye blink and reward prediction error response in anorexia nervosa
Authors: Frank Guido K. W. , Kalina Claire , DeGuzman Marisa C. , Shott Megan E. 
Published: June 2020

AbstractBackgroundFunctional brain imaging has been used to study brain reward function and behavioral traits in anorexia nervosa (AN). Here we tested whether eye blink relates to behavior and brain imaging response as a method that is less costly and more accessible.MethodWe recruited 26 women with AN and 50 healthy matched controls. All underwent a reward‐learning prediction error task during functional magnetic resonance imaging. In addition, eye blink was measured for spontaneous blink rate, baseline blink amplitude, and startle response to an auditory stimulus.ResultsBaseline blink rate, amplitude and startle response were similar between groups. In AN, there were significant positive correlations between spontaneous blink rate and bulimia symptoms, and baseline blink amplitude and prediction error response in right‐sided caudate, insula, and nucleus accumbens. Correlations between eye blink measures and body dissatisfaction or harm avoidance were no longer significant after multiple comparison adjustments.DiscussionThis study provides evidence that measures of eye blink response can be related to brain prediction error response and eating disorder behavior in AN. The catecholamine dopamine contributes to both eye blink and prediction error response providing indirect evidence that it could be a neurobiological correlate that contributes to behaviors relevant to AN.
Pathway to Increase Standards and Competency of eDNA Surveys (PISCeS)—Advancing collaboration and standardization efforts in the field of eDNA
Authors: Loeza‐Quintana Tzitziki , Abbott Cathryn L. , Heath Daniel D. , Bernatchez Louis , Hanner Robert H. 
Published: June 2020

AbstractThis special issue features eleven articles presented at the Pathway to Increase Standards and Competency of eDNA Surveys (PISCeS) conference in October 2018. The prominent theme in this special issue is methodological developments to enhance species and community characterization using eDNA, covering tree main scientific trends: validation of eDNA detections, methodological innovations in eDNA research, and standardization of eDNA practices. Articles in this special issue cover advances on single‐species detection and metabarcoding, and examine eDNA methods standardization. Strong collaboration among academics, regulators, and industry present in the eDNA community is evidenced by the research presented here.