bluuebunny/crossref_metadata_2025_split huggingface dataset:
Continuous Saturated Steam Assisted Low‐temperature Pyrolysis of Corncobs and Selective Production of Furfural
Authors: Ye Jun , Wang Kui , Li Jing , Liu Peng , Xu Junming , Tan WeiHong , Jiang Jianchun 
Published: January 2020

AbstractA facile and selective furfural production technology was introduced by using corncobs as raw materials under saturated steam atmosphere in a fixed bed reactor. It was found that Al2(SO4)3 catalyst has showed a good selective performance with furfural selectivity 64.2% (15.8 wt%). The optimal conditions were pyrolysis temperature 230 °C, steam flow 10 g/min (160 °C) and catalyst loading 7.5 mmol. The reaction parameters such as pyrolysis temperature, catalyst loading and steam flow rate all displayed a positive effect on both corncob conversion and furfural selectivity.The higher steam flow displayed a positive effect on furfural dissolving and products desorption. Removal degree of hemicellulose on each catalytic condition analysis indicated that hemicellulose depolymerization was mainly promoted by lower temperature pyrolysis, and furfural selected production was mainly affected by catalytic effect. This technology provided a low‐cost and low‐temperature catalytic reaction to synthesize furfural, which shows a great potential in industrial production.
Fe/S‐Catalyzed Redox Condensation of o‐Nitrophenols/thiophenols/anilines with Dibenzyl Disulfide: Access to 2‐Arylbenzazoles
Authors: Gan Haifeng 
Published: January 2020

AbstractAn Fe/S‐catalyzed approach to 2‐arylbenzazoles from dibenzyl disulfides and o‐nitrophenols/thiophenols/anilines in the presence of base NMP has been developed. The reactions proceeded in moderate to excellent yields with good functional tolerance and gram‐scale application. Mechanistic research indicated that Fe/S clusters play an important role in the formation of products and DMSO is also important to oxidize benzyl mercaptans to give dibenzyl disulfides.
Macroporous Carbon Material with High Nitrogen Content for Excellent Catalytic Performance of Acetylene Hydrochlorination
Authors: Lu Fangjie , Lu Yusheng , Zhu Mingyuan , Dai Bin 
Published: January 2020

AbstractIn this work, we prepared macroporous carbon catalysts with high N content using melamine as the N‐precursor for in‐situ doping. The catalysts have different carbon‐to‐nitrogen ratios, and the influence of pore structure on the catalytic activity of acetylene hydrochlorination was evaluated. The CN‐2 catalyst shows outstanding catalytic activity of acetylene hydrochlorination (acetylene conversion rate is 98%, VCM selectivity is 99%. Based on the results from temperature programmed desorption (TPD), automatic mercury analyzer, X‐ray photoelectron spectroscopy (XPS) and other characterization techniques, CN‐2 has a nitrogen content of up to 9.74%, a pore size of 300 nm, and strong C2H2 and HCl adsorption. The high activity and stability of CN‐2 indicates that it has great potential as a carbon catalyst of the acetylene hydrochlorination reaction. The used catalyst was dealed with ammonia, and the catalytic performance is certainly recovery, it shows that ammonia treatment is one of the methods of catalyst regeneration.
Key Factors for Template‐Oriented Porous Titania Synthesis: Solvents and Catalysts
Authors: Yin Shanshan , Song Lin , Xia Senlin , Cheng Yajun , Hohn Nuri , Chen Wei , Wang Kun , Cao Wei , Hou Shujin , Müller‐Buschbaum Peter 
Published: January 2020

AbstractVarious types of titania nanostructures are synthesized with a polymer‐templated sol–gel method based on the amphiphilic diblock copolymer polystyrene‐b‐polyethylene oxide (PS‐b‐PEO) in combination with selective incorporation of the titania precursor titanium tetraisopropoxide. Custom tailoring of different types of titania morphologies is realized by changing the phase separation behavior of the PS‐b‐PEO template. Particularly, application of solvents from different categories is found to have a major impact upon the phase separation behavior of PS‐b‐PEO and the final titania film morphology. The amount of available hydrochloric acid catalyst during the gelation process is seen as an additional key factor to induce controllable morphological changes. Scanning electron microscopy and grazing incidence small angle X‐ray scattering measurements are carried out to study the surface and inner structure of porous titania films. Systematic analysis and comparison of different characterization results allow attributing the following three factors to the respectively formed titania nanostructure: the surface energy between PS blocks and surrounding solvent, the aggregation behavior of the titania nanoparticles, and the block‐specific selectivity of the used solvent. For all synthesized titania thin films, an anatase‐type crystallization is confirmed through X‐ray powder diffraction.
Science teachers' sensemaking of the use of epistemic tools to scaffold students' knowledge (re)construction in classrooms
Authors: Sezen‐Barrie Asli , Stapleton Mary K. , Marbach‐Ad Gili 
Published: January 2020

AbstractThis study explores the process of teacher scaffolding student engagement in epistemic tools from the critical sensemaking perspective. Epistemic tools are contextual artifacts manipulated to investigate and evaluate ideas to construct knowledge within the constraints of a disciplines' representational means. The main sources of our data are ~50 min‐long semistructured, responsive interviews with the 14 secondary school science teachers who participated in our professional learning environment (PLE) and implemented the activities from the PLE in their classrooms. We utilized the tools of discourse analysis to explore teacher sensemaking while they learned to teach science with epistemic tools. We then looked at intertextualities of meaning across multiple sets of data such as students' artifacts, pre/postsurveys, audio and video recordings of the workshops, and teachers' written implementation feedback forms. As a result, we recognized a pattern across different classrooms. Teachers would begin with a contextualized goal, and use a pedagogical strategy to scaffold their students as they worked to achieve that goal. Then, all teachers reported they faced some sort of ambiguity (such as grappling with failure, different levels of students). When faced with an ambiguity, teachers would then revise either their contextualized goal or their initial pedagogical strategy to help their students to reach their goals. Finally, we utilized constant‐comparative analysis to identify themes for teachers' contextualized goals. Four major themes emerged, including communicating connections to core ideas of science, making sense of how science works, assessing students' learning process outcomes, and fostering students' epistemic agency. The findings of the study have implications for future research and professional development activities on the use of epistemic practices and tools in classrooms with unique contextual characteristics.
Teaching thermodynamics to middle school students: What are appropriate cognitive demands?
Authors: Linn Marcia C. , Songer Nancy Butler 
Published: January 2020

AbstractWhat cognitive demands foster understanding of thermodynamics for middle school science students? We successively modified the cognitive demands of a 13‐week thermodynamics curriculum for four cohorts of 100‐200 eighth graders while maintaining the same basic experiments and real‐time data collection software. When comparing posttest performance across four versions, we found two‐ to fourfold increases in understanding when (a) students actively predicted outcomes and reconciled results, and (b) students used a heat‐flow model of thermodynamics to integrate their experimental results. We argue that the curriculum must explicitly motivate students to construct understanding, and that middle school students benefit from what we call “pragmatic models” of scientific concepts.
Detection of fetal cardiac anomalies: cost‐effectiveness of increased number of cardiac views
Authors: Bak G. S. , Shaffer B. L. , Madriago E. , Allen A. , Kelly B. , Caughey A. B. , Pereira L. 
Published: January 2020

ABSTRACTObjectiveTo compare the recommended three‐view fetal heart screening method to detect major congenital heart disease (CHD) with more elaborate screening strategies to determine the cost‐effective strategy in unselected (low‐risk) pregnancies.MethodsA decision‐analytic model was designed to compare four screening strategies to identify fetuses with major CHD in a theoretical cohort of 4 000 000 births in the USA. The four strategies were: (1) three views: four‐chamber view (4CV) and views of the left (LVOT) and right (RVOT) ventricular outflow tracts; (2) five views: 4CV, LVOT, RVOT and longitudinal views of the ductal arch and aortic arch; (3) five axial views: 4CV, LVOT, RVOT, three‐vessel (3V) view and three‐vessels‐and‐trachea view; and (4) six views: 4CV, LVOT, RVOT and 3V views and longitudinal views of the ductal arch and aortic arch. Outcomes related to neonatal mortality and neurodevelopmental disability were evaluated. The analysis was performed from a healthcare‐system perspective, with a cost‐effectiveness willingness‐to‐pay threshold set at $100 000 per quality‐adjusted life year (QALY). Baseline analysis, one‐way sensitivity analysis and Monte‐Carlo simulation were performed.ResultsIn our baseline model, screening with five axial views was the optimal strategy, detecting 3520 more CHDs, and resulting in 259 fewer children with neurodevelopmental disability, 40 fewer neonatal deaths and only slightly higher costs, compared with screening with the currently recommended three views. Screening with six views was more effective, but also cost considerably more, compared with screening with five axial views, and had an incremental cost of $490 023/QALY, which was over the willingness‐to‐pay threshold. The five‐view strategy was dominated by the other three strategies, i.e. it was more costly and less effective in comparison. The data were robust when tested with Monte‐Carlo and one‐way sensitivity analysis.ConclusionAlthough current guidelines recommend a minimum of three views for detecting CHD during the mid‐trimester anatomy scan, screening with five axial views is a cost‐effective strategy that may lead to improved outcome compared with three‐view screening. Copyright © 2020 ISUOG. Published by John Wiley & Sons Ltd.
Angiolytische Laserverfahren am Kehlkopf
Authors: Strieth S. , Hagemann J. , Hess M. 
Published: January 2020

ZusammenfassungDurch transorale Lasermikrochirurgie wurden bei der Larynxkarzinomtherapie temporäre Tracheotomien reduziert, die Organerhaltraten erhöht und funktionelle Resultate verbessert. Goldstandard für die laserbasierte transorale Resektion eines Larynxkarzinoms ist der Einsatz des CO2-Laser, dabei sind onkologische Radikalität und postoperative Stimmfunktion individuell abzuwägen. Angiolytische Lasereffekte ermöglichen eine Beeinflussung des Tumormikromilieus durch zielgerichtete Gefäßobliteration und Blockierung der Angiogenese mit Schonung von schwingungsfähigem Gewebe für eine gute Stimmfunktion. Mit der Verabschiedung der S3-Leitlinie zur Diagnostik, Therapie und Nachsorge des Larynxkarzinoms wird eine nationale evidenzbasierte Standardisierung gefördert. International nimmt die Evidenz zur Kalium-Titanyl-Phosphat-Laser-Therapie laryngealer Schleimhautdysplasien und von T1a-Larynxkarzinomen zu. Auch bei juveniler Papillomatose und der Stützlaryngoskopie unter Narkose sowie für ausgewählte Patienten in Lokalanästhesie werden angiolytische Laser eingesetzt.
Critical Ising Model on Random Triangulations of the Disk: Enumeration and Local Limits
Authors: Chen Linxiao , Turunen Joonas 
Published: January 2020

AbstractWe consider Boltzmann random triangulations coupled to the Ising model on their faces, under Dobrushin boundary conditions and at the critical point of the model. The first part of this paper computes explicitly the partition function of this model by solving its Tutte’s equation, extending a previous result by Bernardi and Bousquet-Mélou (J Combin Theory Ser B 101(5):315–377, 2011) to the model with Dobrushin boundary conditions. We show that the perimeter exponent of the model is 7/3 in contrast to the exponent 5/2 for uniform triangulations. In the second part, we show that the model has a local limit in distribution when the two components of the Dobrushin boundary tend to infinity one after the other. The local limit is constructed explicitly using the peeling process along an Ising interface. Moreover, we show that the main interface in the local limit touches the (infinite) boundary almost surely only finitely many times, a behavior opposite to that of the Bernoulli percolation on uniform maps. Some scaling limits closely related to the perimeters of finite clusters are also obtained.
Are RNA networks scale-free?
Authors: Clote P. 
Published: January 2020

AbstractA network is scale-free if its connectivity density function is proportional to a power-law distribution. It has been suggested that scale-free networks may provide an explanation for the robustness observed in certain physical and biological phenomena, since the presence of a few highly connected hub nodes and a large number of small-degree nodes may provide alternate paths between any two nodes on average—such robustness has been suggested in studies of metabolic networks, gene interaction networks and protein folding. A theoretical justification for why many networks appear to be scale-free has been provided by Barabási and Albert, who argue that expanding networks, in which new nodes are preferentially attached to highly connected nodes, tend to be scale-free. In this paper, we provide the first efficient algorithm to compute the connectivity density function for the ensemble of all homopolymer secondary structures of a user-specified length—a highly nontrivial result, since the exponential size of such networks precludes their enumeration. Since existent power-law fitting software, such as , cannot be used to determine a power-law fit for our exponentially large RNA connectivity data, we also implement efficient code to compute the maximum likelihood estimate for the power-law scaling factor and associated Kolmogorov–Smirnov p value. Hypothesis tests strongly indicate that homopolymer RNA secondary structure networks are not scale-free; moreover, this appears to be the case for real (non-homopolymer) RNA networks.
Cavity QED based on room temperature atoms interacting with a photonic crystal cavity: a feasibility study
Authors: Alaeian Hadiseh , Ritter Ralf , Basic Muamera , Löw Robert , Pfau Tilman 
Published: January 2020

AbstractThe paradigm of cavity QED is a two-level emitter interacting with a high-quality factor single-mode optical resonator. The hybridization of the emitter and photon wave functions mandates large vacuum Rabi frequencies and long coherence times; features that so far have been successfully realized with trapped cold atoms and ions, and localized solid-state quantum emitters such as superconducting circuits, quantum dots, and color centers Reiserer and Rempe (Rev Modern Phys 87:1379, 2015), Faraon et al. (Phys Rev 81:033838, 2010). Thermal atoms, on the other hand, provide us with a dense emitter ensemble and in comparison to the cold systems are more compatible with integration, hence enabling large-scale quantum systems. However, their thermal motion and large transit-time broadening is a major bottleneck that has to be circumvented. A promising remedy could benefit from the highly controllable and tunable electromagnetic fields of a nano-photonic cavity with strong local electric-field enhancements. Utilizing this feature, here we investigate the interaction between fast moving thermal atoms and a nano-beam photonic crystal cavity (PCC) with large quality factor and small mode volume. Through fully quantum mechanical calculations, including Casimir–Polder potential (i.e. the effect of the surface on radiation properties of an atom), we show, when designed properly, the achievable coupling between the flying atom and the cavity photon would be strong enough to lead to quantum interference effects in spite of short interaction times. In addition, the time-resolved detection of different trajectories can be used to identify single and multiple atom counts. This probabilistic approach will find applications in cavity QED studies in dense atomic media and paves the way towards realizing large-scale, room-temperature macroscopic quantum systems aimed at out of the lab quantum devices.
Leaflet thickening and stent geometry in sutureless bioprosthetic aortic valves
Authors: Themudo Raquel , Kastengren Mikael , Bacsovics Brolin Elin , Cederlund Kerstin , Svensson Anders , Dalén Magnus 
Published: January 2020

AbstractUnderexpansion of transcatheter heart valves and the surgically implanted Perceval sutureless aortic valve bioprosthesis has been suggested as an underlying mechanism for hypo-attenuated leaflet thickening (HALT). This was a single-center prospective observational study that included 47 patients who underwent surgical aortic valve replacement with the Perceval sutureless bioprosthesis (LivaNova, London, United Kingdom) from 2012 to 2016 and were studied by four-dimensional cardiac computed tomography (CT). The association between overall and regional expansion and the prevalence of HALT was analyzed. In total 46 patients were included in the analysis. HALT was found in 39.1% of patients and the mean overall prosthesis expansion was 75.5 ± 5.2% (range 64.6–84.8%). Overall expansion did not differ between patients with HALT compared with patients without HALT (mean overall expansion 74.0 ± 5.2% vs. 76.5 ± 5.0%, P = 0.11). The prevalence of HALT was lower in patients with overall expansion > 80% compared to patients with expansion < 80% expansion though not significantly (20% vs. 44.4%, P = 0.16). None or trivial regional underexpansion was found in 94.7% of coronary cusps. There was no significant association between regional underexpansion and the prevalence of HALT (mean coronary cusp angle 120 ± 8° vs. 119 ± 10°, P = 0.53). The prevalence of HALT and overall underexpansion was high in the Perceval sutureless bioprosthetic valve. Overall underexpansion was not associated with HALT. Whether severe overall underexpansion increases the risk for HALT requires further study. Regional underexpansion was uncommon in the Perceval sutureless bioprosthetic valve and not associated with HALT.Clinical trial registration Unique identifier: NCT03753126 (http://www.clinicaltrials.gov).
Antibody signatures in patients with histopathologically defined multiple sclerosis patterns
Authors: Stork Lidia , Ellenberger David , Ruprecht Klemens , Reindl Markus , Beißbarth Tim , Friede Tim , Kümpfel Tania , Gerdes Lisa A. , Gloth Mareike , Liman Thomas , Paul Friedemann , Brück Wolfgang , Metz Imke 
Published: January 2020

AbstractEarly active multiple sclerosis (MS) lesions can be classified histologically into three main immunopathological patterns of demyelination (patterns I–III), which suggest pathogenic heterogeneity and may predict therapy response. Patterns I and II show signs of immune-mediated demyelination, but only pattern II is associated with antibody/complement deposition. In pattern III lesions, which include Baló’s concentric sclerosis, primary oligodendrocyte damage was proposed. Serum antibody reactivities could reflect disease pathogenesis and thus distinguish histopathologically defined MS patterns. We established a customized microarray with more than 700 peptides that represent human and viral antigens potentially relevant for inflammatory demyelinating CNS diseases, and tested sera from 66 patients (pattern In = 12; IIn = 29; IIIn = 25, including 8 with Baló’s), healthy controls, patients with Sjögren’s syndrome and stroke patients. Cell-based assays were performed for aquaporin 1 (AQP1) and AQP4 antibody detection. No single peptide showed differential binding among study cohorts. Because antibodies can react with different peptides from one protein, we also analyzed groups of peptides. Patients with pattern II showed significantly higher reactivities to Nogo-A peptides as compared to patterns I (p = 0.02) and III (p = 0.02). Pattern III patients showed higher reactivities to AQP1 (compared to pattern Ip = 0.002, pattern IIp = 0.001) and varicella zoster virus (VZV, compared to pattern IIp = 0.05). In patients with Baló’s, AQP1 reactivity was also significantly higher compared to patients without Baló’s (p = 0.04), and the former revealed distinct antibody signatures. Histologically, Baló’s patients showed loss of AQP1 and AQP4 in demyelinating lesions, but no antibodies binding conformational AQP1 or AQP4 were detected. In summary, higher reactivities to Nogo-A peptides in pattern II patients could be relevant for enhanced axonal repair and remyelination. Higher reactivities to AQP1 peptides in pattern III patients and its subgroup of Baló’s patients possibly reflect astrocytic damage. Finally, latent VZV infection may cause peripheral immune activation.
Heterochromatin formation in Drosophila requires genome-wide histone deacetylation in cleavage chromatin before mid-blastula transition in early embryogenesis
Authors: Walther Matthias , Schrahn Sandy , Krauss Veiko , Lein Sandro , Kessler Jeannette , Jenuwein Thomas , Reuter Gunter 
Published: January 2020

AbstractSu(var) mutations define epigenetic factors controlling heterochromatin formation and gene silencing in Drosophila. Here, we identify SU(VAR)2-1 as a novel chromatin regulator that directs global histone deacetylation during the transition of cleavage chromatin into somatic blastoderm chromatin in early embryogenesis. SU(VAR)2-1 is heterochromatin-associated in blastoderm nuclei but not in later stages of development. In larval polytene chromosomes, SU(VAR)2-1 is a band-specific protein. SU(VAR)2-1 directs global histone deacetylation by recruiting the histone deacetylase RPD3. In Su(var)2-1 mutants H3K9, H3K27, H4K8 and H4K16 acetylation shows elevated levels genome-wide and heterochromatin displays aberrant histone hyper-acetylation. Whereas H3K9me2- and HP1a-binding appears unaltered, the heterochromatin-specific H3K9me2S10ph composite mark is impaired in heterochromatic chromocenters of larval salivary polytene chromosomes. SU(VAR)2-1 contains an NRF1/EWG domain and a C2HC zinc-finger motif. Our study identifies SU(VAR)2-1 as a dosage-dependent, heterochromatin-initiating SU(VAR) factor, where the SU(VAR)2-1-mediated control of genome-wide histone deacetylation after cleavage and before mid-blastula transition (pre-MBT) is required to enable heterochromatin formation.