bluuebunny/crossref_metadata_2025_split huggingface dataset:
Atmospheric Ducting and Beyond‐Line‐of‐Sight Communication
Authors: Dinc Ergin , Akan Ozgur B. 
Published: November 2018

AbstractAtmospheric ducts are caused by rapid decrease in the refractive index of the lower atmosphere, and they significantly alter the near‐surface wave propagation by trapping propagating signals. In this way, atmospheric ducts behave like a waveguide, and trapped signals can even propagate more than 1000 km in the ducting layer. Therefore, communication and radar systems can be adversely affected by the presence of atmospheric ducts. However, atmospheric ducts not only create interference, but also enable an alternative and promising way for communicating to extreme distances, also known as beyond‐Line‐of‐Sight (b‐LoS) communication. In this article, a comprehensive introduction to atmospheric ducts and their effects on near‐surface wave propagation as well as wave propagation modeling and possible utilization of atmospheric ducts for b‐LoS communication systems are presented.
Wind Power Plant Control
Authors: Chen Zhe 
Published: November 2018

AbstractThis article introduces wind turbine technology and presents wind power plant control. In the first part, wind turbine, wind power conversion system, and turbine control are overviewed briefly. The second part details wind power plants. The third part covers the wind power plant control, including the general wind power plant control, as well as more advanced topics, such as the wind power plant as a generator in a power grid, wind power plant optimal operation, and wind power plants in multiple energy systems. The third part also presents grid requirements, performance, interaction with other equipment in the power grid, and use of energy storage in wind power plants. In addition, optimal operation that considers the wake effect, power losses in wind turbines, and collection systems is discussed. A reference list is given for the readers who wish to find more details about these technologies.
Supramolecular Antifouling Additives for Robust and Efficient Functionalization of Elastomeric Materials: Molecular Design Matters
Authors: Ippel Bastiaan D. , Keizer Henk M. , Dankers Patricia Y. W. 
Published: November 2018

AbstractThe ultimate functionality of elastomeric materials can be largely influenced by the molecular design of antifouling additives that interact through directed hydrogen bonding bisurea motifs. Herein, three additives, composed of matching bisurea groups and antifouling oligo(ethylene glycol) (OEG) functionalities, are judiciously designed. The first additive is composed of one bisurea and one OEG, the second additive of one bisurea and two OEGs, and the third additive of two bisurea and one OEG. On solution‐cast films, non‐cell adhesive properties are dependent on the amount of incorporated OEG irrespective of the bisurea design; however, on 3D electrospun scaffolds only the additive that consists of two bisurea moieties connected via an OEG functionality ensures proper non‐cell adhesive properties. Interestingly, robust non‐cell adhesive properties are maintained, both with repeated cell seeding and after partial enzymatic degradation of the scaffold. These results highlight the importance of additive design in supramolecular functionalization and show that translation from simple 2D solution‐cast films to 3D electrospun scaffolds is not trivial with respect to additive presentation and functionality.
PbTiO3 as Electron‐Selective Layer for High‐Efficiency Perovskite Solar Cells: Enhanced Electron Extraction via Tunable Ferroelectric Polarization
Authors: Wang Ming‐Zi , Feng Hong‐Jian , Qian Chong‐Xin , He Jiawei , Feng Jiangshan , Cao Yong‐Hua , Yang Kang , Deng Zun‐Yi , Yang Zhou , Yao Xi , Zhou Jianping , Liu Shengzhong (Frank) , Zeng Xiao Cheng 
Published: November 2018

AbstractPbTiO3 (PTO) is explored as a versatile and tunable electron‐selective layer (ESL) for perovskite solar cells. To demonstrate effectiveness of PTO for electron–hole separation and charge transfer, perovskite solar cells are designed and fabricated in the laboratory with the PTO as the ESL. The cells achieve a power conversion efficiency (PCE) of ≈12.28% upon preliminary optimization. It is found that the PTO ferroelectric layer can not only increase the PCE, but also tune the photocurrent via tuning PTO's ferroelectric polarization. Moreover, to understand the physical mechanism underlying the carrier transport by the ferroelectric polarization, the electronic structure of PTO/CH3NH3PbI3 heterostructure is computed using the first‐principles methods, for which the triplet state is used to simulate charge transfer in the heterostructure. It is shown that the synergistic effect of type II band alignment and the specific ferroelectric polarization direction provide the effective extraction of electrons from the light absorber, while minimize recombination of photogenerated electron–hole pairs. Overall, the ferroelectric PTO is a promising and tunable ESL for optimizing electron transport in the perovskite solar cells. The design offers a different strategy for altering direction of carrier transport in solar cells.
Polymorph Selectivity of Coccolith‐Associated Polysaccharides from Gephyrocapsa Oceanica on Calcium Carbonate Formation In Vitro
Authors: Walker Jessica M. , Marzec Bartosz , Lee Renee B. Y. , Vodrazkova Kristyna , Day Sarah J. , Tang Chiu C. , Rickaby Rosalind E. M. , Nudelman Fabio 
Published: November 2018

AbstractCoccolith‐associated polysaccharides (CAPs) are thought to be a key part of the biomineralization process in coccolithophores; however, their role is not fully understood. Two different systems that promote different polymorphs of calcium carbonate are used to show the effect of CAPs on nucleation and polymorph selection in vitro. Using a combination of time‐resolved cryo‐transmission electron microscopy and scanning electron microscopy, the mechanisms of calcite nucleation and growth in the presence of the intracrystalline fraction are examined containing CAPs extracted from coccoliths from Gephyrocapsa oceanica and Emiliania huxleyi, two closely related coccolithophore species. The CAPs extracted from G. oceanica are shown to promote calcite nucleation in vitro, even under conditions favoring the kinetic products of calcium carbonate, vaterite, and aragonite. This is not the case with CAPs extracted from E. huxleyi, suggesting that the functional role of CAPs in vivo may be different between the two species. Additionally, high‐resolution synchrotron powder X‐ray diffraction has revealed that the polysaccharide is located between grain boundaries of both calcite produced in the presence of the CAPs in vitro and biogenic calcite, rather than within the crystal lattice.
Ultrafast Sodium Full Batteries Derived from XFe (X = Co, Ni, Mn) Prussian Blue Analogs
Authors: Ge Peng , Li Sijie , Shuai Honglei , Xu Wei , Tian Ye , Yang Li , Zou Guoqiang , Hou Hongshuai , Ji Xiaobo 
Published: November 2018

AbstractExploring high‐rate electrode materials with excellent kinetic properties is imperative for advanced sodium‐storage systems. Herein, novel cubic‐like XFe (X = Co, Ni, Mn) Prussian blue analogs (PBAs), as cathodes materials, are obtained through as‐tuned ionic bonding, delivering improved crystallinity and homogeneous particles size. As expected, Ni‐Fe PBAs show a capacity of 81 mAh g−1 at 1.0 A g−1, mainly resulting from their physical–chemical stability, fast kinetics, and “zero‐strain” insertion characteristics. Considering that the combination of elements incorporated with carbon may increase the rate of ion transfer and improve the lifetime of cycling stability, they are expected to derive binary metal‐selenide/nitrogen‐doped carbon as anodes. Among them, binary Ni0.67Fe0.33Se2 coming from Ni‐Fe PBAs shows obvious core–shell structure in a dual‐carbon matrix, leading to enhanced electron interactions, electrochemical activity, and “metal‐like” conductivity, which could retain an ultralong‐term stability of 375 mAh g−1 after 10 000 loops even at 10.0 A g−1. The corresponding full‐cell Ni‐Fe PBAs versus Ni0.67Fe0.33Se2 deliver a remarkable Na‐storage capacity of 302.2 mAh g−1 at 1.0 A g−1. The rational strategy is anticipated to offer more possibilities for designing advanced electrode materials used in high‐performance sodium‐ion batteries.
Palladium‐Catalyzed Regioselective Synthesis of 1‐Hydroxycarbazoles Under Aerobic Conditions
Authors: Youn So Won , Kim Young Ho , Jo Yoon Hyung 
Published: November 2018

AbstractA palladium‐catalyzed aerobic C−H amidation of N‐Ts‐2‐amino‐3′‐hydroxylbiaryls has been developed to afford a diverse range of 1‐hydroxycarbazoles with high regioselectivity and efficiency. This protocol benefits from operational simplicity, robustness, and sustainability with the use of ambient air as the sole terminal oxidant. Further elaboration of the products obtained from this process provides facile access to various carbazole alkaloids including carbazolequinones and biscarbazoles. A mechanism involving dual directing group‐assisted regioselective C−H activation at the more sterically hindered C2′‐position of 2‐amino‐3′‐hydroxylbiaryls is proposed.magnified image
Interfacial Dynamics and Contact Passivation in Perovskite Solar Cells
Authors: De Bastiani Michele , Aydin Erkan , Allen Thomas , Walter Daniel , Fell Andreas , Peng Jun , Gasparini Nicola , Troughton Joel , Baran Derya , Weber Klaus , White Thomas P. , De Wolf Stefaan 
Published: November 2018

AbstractCharge accumulation at the electron and hole transport layers generates anomalous electrical behavior in perovskite solar cells (PSCs). Hysteresis in the current–voltage characteristic and recombination at the interfaces are the clearest manifestations of this phenomenon, which compromises device performance and stability. Here, the underlying charge‐carrier dynamics of a variety of PSCs are investigated by analyzing their transient photocurrent response. Towards shorter time scales, PSCs often show increasingly severe hysteretic responses. This phenomenon is correlated with the presence of interfacial accumulated charges that hinders the photogenerated carrier extraction process. However, introducing passivating contacts improves the carrier‐injection properties and the devices become completely hysteresis free. These results underline the importance of contact passivation for PSCs and the need to further develop new passivating interlayers that simultaneously eliminate charge‐carrier recombination and provide selective transport for each carrier type at the PSC's contacts.
A cadaveric model for measuring sinonasal continuous positive airway pressure—a proof‐of‐concept study
Authors: Rimmer Ryan A. , Chitguppi Chandala , Garcia Hermes G. , Koszewski Ian J. , Nyquist Gurston G. , Rosen Marc R. , Huntley Colin , Evans James J. , Rabinowitz Mindy R. 
Published: November 2018

BackgroundObstructive sleep
apnea is a common respiratory disorder that can have negative effects on health and quality of life. Positive pressure therapy (CPAP) is the primary treatment. There is a lack of consensus on the risk of postoperative CPAP after endoscopic sinus or skull base surgery. We present a proof‐of‐concept cadaver model for measuring sinonasal pressure delivered by CPAP.MethodsThree fresh cadaver heads were prepared by removing the calvaria and brain. Sphenoidotomies were made and sellar bone was removed. Pressure sensors were placed in the midnasal cavity, sphenoid sinus, and sella. CPAP was applied and the delivered pressure was recorded at increasing levels of positive pressure. Paired t tests and intraclass correlation coefficients were used to analyze results.ResultsIncreases in positive pressure led to increased pressure recordings for all locations. Nasal cavity pressure was, on average, 81% of delivered CPAP. Pressure was highest in the sphenoid sinus. The effect of middle turbinate medialization on intrasphenoid pressure was not statistically significant in 2 heads. Intrasellar pressure was 80% of delivered CPAP with lateralized turbinates and 84% with medialized turbinates. Pressure recordings demonstrated excellent reliability for all locations. All heads developed non‒sellar‐based cranial base leaks at higher pressures. Cribriform region leaks were successfully sealed with DuraSeal®.ConclusionOur proof‐of‐concept cadaver model represents a novel approach to measure pressures delivered to the nasal cavity and anterior skull base by CPAP. With further study, it may have broader clinical application to guide the safe postoperative use of CPAP in this population.
Bioabsorbable steroid‐releasing implants in the frontal sinus ostia: a pooled analysis
Authors: Singh Ameet , Luong Amber U. , Fong Karen J. , Ow Randall A. , Han Joseph K. , Gerencer Roland , Stolovitzky J. Pablo , Stambaugh James W , Raman Aarthi 
Published: November 2018

BackgroundBioabsorbable steroid‐releasing implants (mometasone furoate, 370 μg) are effective for improving postsurgical outcomes in the frontal sinus ostia (FSO). In this study we evaluated the effect of these implants on frontal outcomes in various patient subgroups with chronic rhinosinusitis (CRS) using pooled data from 2 randomized, controlled trials (RCTs).MethodsA total of 160 subjects were enrolled in 2 RCTs. After surgery, subjects were randomized to receive an implant in 1 FSO with the contralateral side as control. Data through day 90 from the 2 studies were pooled and subgroup analyses were performed.ResultsAt day 30, relative to controls, steroid‐releasing implants significantly reduced the need for postoperative interventions by 46.8% (95% confidence interval [CI], −60.7 to −27.9), for surgical interventions by 51.2% (95% CI, −68.2 to −25.2), and for oral steroid interventions by 37.2% (95% CI, −54.6 to −13.1) in the pooled data set. At day 90, statistically significant reductions (p < 0.05) in the need for postoperative interventions (relative reduction [RR], 30.2%), restenosis/occlusion rate (RR, 31.7%), and inflammation score (absolute difference, −6.0), and increase in estimated FSO diameter (absolute difference, 1 mm), favoring the treated side, were observed. Subgroup analyses of the pooled data showed statistically significant improvements (p < 0.05) at day 90 in restenosis/occlusion rate, and estimated FSO diameter, favoring the treated side across subgroups, with no statistically significant subgroup‐by‐treatment interactions.ConclusionBioabsorbable steroid‐releasing sinus implants improve outcomes of frontal sinus surgery through 90 days, irrespective of asthma status, previous endoscopic sinus surgery, extent of surgery, extent of polyps, or Lund‐Mackay computed tomography stage in the FSO.
The Influence of Non‐Markovian Characters on Quantum Adiabatic Evolution
Authors: Zeng Ye‐Xiong , Gebremariam Tesfay , Ding Ming‐Song , Li Chong 
Published: November 2018

AbstractThe influence of non‐Markovian characters on the adiabatic evolution is investigated. The adiabatic Raman process is simulated in a three‐level system coupled to two independent environments. The results show that the memory effect of environments can restrain the decoherence effect of the system. Even if the system has strong decay rates in the non‐Markovian environments, the adiabatic population transfer can be still completed efficiently. Moreover, the memory effect can reduce the dependence of the adiabatic evolution on the Rabi frequency. Specifically, the two independent non‐Markovian baths can suppress the decoherence more effectively than a single non‐Markovian bath.
Aerobic Toluene Oxidation Catalyzed by Subnano Metal Particles
Authors: Huda Miftakhul , Minamisawa Keigo , Tsukamoto Takamasa , Tanabe Makoto , Yamamoto Kimihisa 
Published: November 2018

AbstractSubnanocatalysts (SNCs) containing various noble metals (Cu, Ru, Rh, Pd, or Pt) with sizes of approximately 1 nm were synthesized using dendritic poly(phenylazomethine)s as a macromolecular template. These materials exhibit high catalytic performance during toluene oxidation without the use of harmful solvents or explosive oxidants, resulting in the formation of valuable organic products, including benzoic acid as the major product. In particular, Pt19 SNC with a narrow particle size distribution exhibits extraordinary catalytic activity, with a turnover frequency of 3238 atom−1 h−1, which is 1700 times greater than that obtained by commercial Pt/C catalysts.
Insights into the Biosynthesis of Cyclic Guanidine Alkaloids from Crambeidae Marine Sponges
Authors: Silva Siguara B. L. , Oberhänsli François , Tribalat Marie‐Aude , Genta‐Jouve Grégory , Teyssié Jean‐Louis , Dechraoui‐Bottein Marie‐Yasmine , Gallard Jean‐François , Evanno Laurent , Poupon Erwan , Thomas Olivier P. 
Published: November 2018

AbstractAmong the outstanding chemical diversity found in marine sponges, cyclic guanidine alkaloids, present in species of the family Crambeidae, are particularly attractive, not only because of their unique chemical features, but also due to a broad range of biological activities. Despite a growing interest in these natural products as therapeutic agents, their metabolic pathway has not been experimentally investigated. Ex situ feeding experiments using radiolabeled precursors performed on the Mediterranean sponge Crambe crambe suggest arginine and fatty acids as precursors in the metabolic pathway of crambescins. A subsequent bio‐inspired approach supported the change of paradigm in the metabolic pathway of cyclic guanidine alkaloids. A large part of the chemical diversity of this family would therefore originate from a tethered Biginelli‐like reaction between C‐2/C‐3 activated fatty acids and a central guanidinylated pyrrolinium.
Auf dem Weg zur Evolution artifizieller Metalloenzyme – aus einem Protein‐Engineering‐Blickwinkel
Authors: Markel Ulrich , Sauer Daniel F. , Schiffels Johannes , Okuda Jun , Schwaneberg Ulrich 
Published: November 2018

AbstractDurch den Einbau synthetischer metallorganischer Cofaktoren in Proteingerüste wird eine neue Klasse von Katalysatoren generiert, die als Biohybridkatalysatoren oder artifizielle Metalloenzyme bezeichnet werden. Biohybridkatalysatoren können sowohl in der ersten Koordinationssphäre des Metallkomplexes als auch in der zweiten, vom Proteingerüst bereitgestellten Koordinationssphäre chemisch modifiziert werden. Das Reengineering von Proteingerüsten mittels Methoden der gelenkten Evolution stellt Herausforderungen an das Durchmusterungssystem und bedingt eine ausgeklügelte Metall‐Cofaktor‐Konjugation. In diesem Kurzaufsatz fassen wir die Forschungsbemühungen zur Entwicklung von Hochdurchsatz‐Durchmusterungsverfahren für Biohybridkatalysatoren zusammen. Darüber hinaus beleuchten wir das Potenzial solcher Katalysatoren und die Hürden, die überwunden werden müssen, um von Biohybridkatalysatoren zu artifiziellen Metalloproteinen mit den Charakteristika natürlicher Enzyme zu kommen.
DNA Surface Technology: From Gene Sensors to Integrated Systems for Life and Materials Sciences
Authors: Schneider Ann‐Kathrin , Niemeyer Christof M. 
Published: November 2018

AbstractThe evolution of DNA microarray technology has led to sophisticated DNA chips that are being used as routine tools for fundamental and applied genome research such as genotyping and expression profiling. Owing to their capability for highly parallel, site‐directed immobilization of complementary nucleic acids through canonical Watson–Crick base‐pairing, however, DNA‐modified surfaces can also be used for the assembly of complex surface architectures comprised of non‐nucleic acid compounds, such as proteins or colloidal materials. Furthermore, implementation of functional DNA devices and structural DNA nanotechnology can unlock the full potential of DNA surfaces. Based on case studies from diagnostics, sensing, proteome research, cell adhesion, and cell signaling, we show how classical gene sensors have developed into modern integrated systems and platforms for various applications in life sciences and materials research.
Towards the Evolution of Artificial Metalloenzymes—A Protein Engineer's Perspective
Authors: Markel Ulrich , Sauer Daniel F. , Schiffels Johannes , Okuda Jun , Schwaneberg Ulrich 
Published: November 2018

AbstractIncorporating artificial metal‐cofactors into protein scaffolds results in a new class of catalysts, termed biohybrid catalysts or artificial metalloenzymes. Biohybrid catalysts can be modified chemically at the first coordination sphere of the metal complex, as well as at the second coordination sphere provided by the protein scaffold. Protein‐scaffold reengineering by directed evolution exploits the full power of nature's diversity, but requires validated screening and sophisticated metal cofactor conjugation to evolve biohybrid catalysts. In this Minireview, we summarize the recent efforts in this field to establish high‐throughput screening methods for biohybrid catalysts and we show how non‐chiral catalysts catalyze reactions enantioselectively by highlighting the first successes in this emerging field. Furthermore, we shed light on the potential of this field and challenges that need to be overcome to advance from biohybrid catalysts to true artificial metalloenzymes.
Crystal Structure of Regularly Th‐Symmetric [U(NO3)6]2− Salts with Hydrogen Bond Polymers of Diamide Building Blocks
Authors: Takao Koichiro , Kazama Hiroyuki , Ikeda Yasuhisa , Tsushima Satoru 
Published: November 2018

AbstractHexanitratouranate(IV), [U(NO3)6]2−, has been crystallized with anhydrous H+‐involving hydrogen bond polymers connected by selected diamide building blocks. Thanks to the significant moderation of electrostatic interactions between the anions and cations, the molecular structure of [U(NO3)6]2− in these compounds is regularly Th‐symmetric. The f–f transitions stemming from 5f2 configuration of U4+ are strictly forbidden by the Laporte selection rule in such a centrosymmetric system, so that the obtained compounds are nearly colourless in contrast to other UIV species usually coloured in green.
Assessment of Middle Ear Anatomy Teaching Methodologies Using Microscopy versus Endoscopy: A Randomized Comparative Study
Authors: Anschuetz Lukas , Huwendiek Sören , Stricker Daniel , Yacoub Abraam , Wimmer Wilhelm , Caversaccio Marco 
Published: November 2018

Teaching methodologies for the anatomy of the middle ear have not been investigated greatly due to the middle ear’s highly complex structure and hidden location inside of the temporal bone. The aim of this randomized study was to quantitatively compare the suitability of using microscope‐ and endoscope‐based methods for teaching the anatomy of the middle ear. We hypothesize that the endoscopic approach will be more efficient compared to the microscopic approach. To answer the study questions, 33 sixth‐year medical students, residents and otorhinolaryngology specialists were randomized either into the endoscopy or the microscopy group. Their anatomical knowledge was assessed using a structured anatomical knowledge test before and after each session. Each participant received tutoring on a human cadaveric specimen using one of the two methods. They then performed a hands‐on dissection. After 2–4 weeks, the same educational curriculum was repeated using the other technique. The mean gains in anatomical knowledge for the specialists, residents, and medical students were +19.0%, +34.6%, and +23.4%, respectively. Multivariate analyses identified a statistically significant increase in performance for the endoscopic method compared to the microscopic technique (P < 0.001). For the recall of anatomical structures during dissection, the endoscopic method outperformed the microscopic technique independently of the randomization or the prior training level of the attendees (P < 0.001). In conclusion, the endoscopic approach to middle ear anatomy education is associated to an improved gain in knowledge as compared to the microscopic approach. The participants subjectively preferred the endoscope for educational purposes.