bluuebunny/crossref_metadata_2025_split huggingface dataset:
American Academy of Orthopedic Surgeons Appropriate Use Criteria for Hip Preservation Surgery: Variables That Drive Appropriateness for Surgery
Authors: Riddle Daniel L. , Perera Robert A. 
Published: January 2019

ObjectiveDetermining appropriate candidates for hip preservation surgery is challenging because criteria for judging appropriateness are not defined. The American Academy of Orthopaedic Surgeons (AAOS) recently published a hip preservation surgery appropriateness classification system using the RAND/University of California, Los Angeles approach. This study was undertaken to determin the extent and pattern of contribution of each of the variables used to predict the appropriateness of hip preservation surgery.MethodsAn AAOS‐appointed multidisciplinary expert panel wrote 270 clinical vignettes incorporating all permutations of 5 indication variables derived from an evidence synthesis. A second independent panel of experts rated the appropriateness of each vignette during multiple Delphi surveys. We used logistic regression to determine the relative contribution of each variable to classification. We also used a classification‐tree approach to determine which indication variables, in combination, contributed to the final classification.ResultsOdds ratios from the regression indicated that patient age and radiographic hip osteoarthritis (OA) evaluation were the main indications of appropriateness classification (e.g., the odds ratio for age <40 years was >999.99, with age >65 years as the referent group, for “appropriate/may be appropriate” as compared to “rarely appropriate” vignettes). Hip range of motion, risk for negative outcome, and function‐limiting pain did not meaningfully contribute to the final classification.ConclusionThe AAOS appropriateness classification system for hip preservation surgery is driven almost exclusively by age and radiographic hip OA evaluation. Additional research on appropriateness classification for hip preservation surgery is needed to identify important indication variables beyond age and radiographic hip findings.
Giant Piezoelectricity of Ternary Perovskite Ceramics at High Temperatures
Authors: Zhao Tian‐Long , Bokov Alexei A. , Wu Jingen , Wang Hongli , Wang Chun‐Ming , Yu Yang , Wang Chun‐Lei , Zeng Kaiyang , Ye Zuo‐Guang , Dong Shuxiang 
Published: January 2019

AbstractHere, novel ferroelectric ceramics of (0.95 − x)BiScO3‐xPbTiO3‐0.05Pb(Sn1/3Nb2/3)O3 (BS‐xPT‐PSN) of complex perovskite structure are reported with compositions near the morphotropic phase boundary (MPB), and which exhibit a piezoelectric coefficient d33 = 555 pC N−1, a large‐signal coefficient ≈ 1200 pm V−1 at room temperature, and a high Curie temperature TC of 408 °C. More interestingly, this ternary system exhibits a giant and stable piezoelectric response at 200 °C with a large‐signal ≈ 2500 pm V−1, matching that of the costly relaxor‐based piezoelectric single crystals at room temperature. The mechanisms of such giant piezoelectricity and its characteristic temperature dependence are attributed to the spontaneous polarization rotation and extension under an electric field and the MPB‐related phase transition. The findings reveal that the BS‐xPT‐PSN ceramics constitute a new family of high‐performance piezoelectric materials suitable for electromechanical transducers that can be operated at high temperatures (at 200 °C, or higher).
Dodecaborane‐Based Dopants Designed to Shield Anion Electrostatics Lead to Increased Carrier Mobility in a Doped Conjugated Polymer
Authors: Aubry Taylor J. , Axtell Jonathan C. , Basile Victoria M. , Winchell K. J. , Lindemuth Jeffrey R. , Porter Tyler M. , Liu Ji‐Yuan , Alexandrova Anastassia N. , Kubiak Clifford P. , Tolbert Sarah H. , Spokoyny Alexander M. , Schwartz Benjamin J. 
Published: January 2019

AbstractOne of the most effective ways to tune the electronic properties of conjugated polymers is to dope them with small‐molecule oxidizing agents, creating holes on the polymer and molecular anions. Undesirably, strong electrostatic attraction from the anions of most dopants localizes the holes created on the polymer, reducing their mobility. Here, a new strategy utilizing a substituted boron cluster as a molecular dopant for conjugated polymers is employed. By designing the cluster to have a high redox potential and steric protection of the core‐localized electron density, highly delocalized polarons with mobilities equivalent to films doped with no anions present are obtained. AC Hall effect measurements show that P3HT films doped with these boron clusters have conductivities and polaron mobilities roughly an order of magnitude higher than films doped with F4TCNQ, even though the boron‐cluster‐doped films have poor crystallinity. Moreover, the number of free carriers approximately matches the number of boron clusters, yielding a doping efficiency of ≈100%. These results suggest that shielding the polaron from the anion is a critically important aspect for producing high carrier mobility, and that the high polymer crystallinity required with dopants such as F4TCNQ is primarily to keep the counterions far from the polymer backbone.
A New Type of Li‐Rich Rock‐Salt Oxide Li2Ni1/3Ru2/3O3 with Reversible Anionic Redox Chemistry
Authors: Li Xiang , Qiao Yu , Guo Shaohua , Jiang Kezhu , Ishida Masayoshi , Zhou Haoshen 
Published: January 2019

AbstractLi‐rich oxide cathodes are of prime importance for the development of high‐energy lithium‐ion batteries (LIBs). Li‐rich layered oxides, however, always undergo irreversible structural evolution, leading to inevitable capacity and voltage decay during cycling. Meanwhile, Li‐rich cation‐disordered rock‐salt oxides usually exhibit sluggish kinetics and inferior cycling stability, despite their firm structure and stable voltage output. Herein, a new Li‐rich rock‐salt oxide Li2Ni1/3Ru2/3O3 with Fd‐3m space group, where partial cation‐ordering arrangement exists in cationic sites, is reported. Results demonstrate that a cathode fabricated from Li2Ni1/3Ru2/3O3 delivers a large capacity, outstanding rate capability as well as good cycling performance with negligible voltage decay, in contrast to the common cations disordered oxides with space group Fm‐3m. First principle calculations also indicate that rock‐salt oxide with space group Fd‐3m possesses oxygen activity potential at the state of delithiation, and good kinetics with more 0‐TM (TM = transition metals) percolation networks. In situ Raman results confirm the reversible anionic redox chemistry, confirming O2−/O− evolution during cycles in Li‐rich rock‐salt cathode for the first time. These findings open up the opportunity to design high‐performance oxide cathodes and promote the development of high‐energy LIBs.
Novel Water Harvesting Fibrous Membranes with Directional Water Transport Capability
Authors: Wu Jing , Zhou Hua , Wang Hongxia , Shao Hao , Yan Guilong , Lin Tong 
Published: January 2019

AbstractPrevious studies about water harvesting from airborne moisture, which is driven by a directional water transport principle, are based on either a 2D surface or a 1D filament. Porous membranes with a directional water transport capability are seldom used for water harvesting. Herein, a novel hydrophobic/hydrophilic directional‐wicking nanofibrous membrane is reported showing enhanced water harvesting ability. In comparison to the hydrophobic or hydrophilic membranes of the same structure and dimension, the directional wicking fibrous membranes have much higher water harvesting capacity. This fantastic water harvesting capability is originated from strong force to draw water from the hydrophobic to the superhydrophilic layer and ever permeable channels formed by the hydrophobic fibrous structure. Larger pores in the hydrophobic layer and smaller pores in the superhydrophilic layer facilitate water harvesting because of the enhanced directional wicking ability. The variation in pore dimension between the hydrophobic and the hydrophilic layers can result in 1.7 times difference in water harvesting capacity. These novel understandings may be useful for the development of advanced water harvesters for various applications.
Maximal Visible Light Energy Transfer to Ultrathin Semiconductor Films Enabled by Dispersion Control
Authors: Jung Gwang‐Hun , Yoo SeokJae , Kim Jin‐Soo , Park Q‐Han 
Published: January 2019

AbstractIncreasing light absorption in an ultrathin semiconductor is critical for developing thin‐film photovoltaic devices. Here, it is shown that a maximal absorption of visible light is possible through controlling the dispersion of thin‐film materials. The ideal dispersion relation is determined for the permittivity of a thin film placed on a reflector with a dielectric spacer, and it is explained how the ideal dispersion relation can be realized for semiconductor materials possessing bandgaps. To experimentally verify dispersion control and maximal absorption, the permittivity of lead selenide (PbSe) thin film is tailored by controlling its polycrystallinity through the sputtering conditions. The measured reflectance of a dispersion‐controlled PbSe film (9 nm) deposited on an SiO2 (48 nm)/Al substrate shows a record level of absorbance for PbSe film of 88% taken as an average over the entire visible spectrum. This value is close to the theoretical maximum value of 95%. Overall, the dispersion control scheme offers promising avenues for thin‐film solar cell research.
The role of social grants on commercialization among smallholder farmers in South Africa: Evidence from a continuous treatment approach
Authors: Sinyolo Sikhulumile , Mudhara Maxwell , Wale Edilegnaw 
Published: January 2019

AbstractThis study examined the role of social grants to smallholder producers’ incentives to sell maize marketable surplus. The study used the generalized propensity score (GPS) matching method to analyse the data collected from a sample of 774 smallholder producers in KwaZulu‐Natal. The results support the disincentive hypothesis, demonstrating a negative association between social grants and market participation levels of smallholders. The study findings imply that policies aimed at increasing smallholder commercialization should also focus on how to reduce the disincentive effects of social grants.
Controlling an SN2 Reaction by Electronic and Vibrational Excitation: Tip‐Induced Ether Cleavage on Si(001)
Authors: Mette Gerson , Adamkiewicz Alexa , Reutzel Marcel , Koert Ulrich , Dürr Michael , Höfer Ulrich 
Published: January 2019

AbstractControlling chemical reactions beyond thermally activated reaction schemes can open alternative reaction channels, and thus lead to new final products. Herein, we show for tetrahydrofuran (THF) cleavage on Si(001), the surface analogue of an SN2 reaction, that excitation by electrons from the tip of a scanning tunneling microscope (STM) not only opens new reaction channels, but that different final products can be selectively addressed by the type of excitation: Above a threshold voltage of 2.5 V, direct excitation by electron transfer into the antibonding C−O orbital of the THF molecules induces ether cleavage of the datively bonded intermediate of THF on Si(001). Below the threshold, ether cleavage is induced by multiple excitation of vibrational modes. In both modes of excitation, additional final configurations were observed when compared to the thermally activated reaction. The branching ratios of the final configurations are different for the two different excitation mechanisms, which in turn can be controlled by the applied sample bias.
Rotational Signatures of Dispersive Stacking in the Formation of Aromatic Dimers
Authors: Fatima Mariyam , Steber Amanda L. , Poblotzki Anja , Pérez Cristóbal , Zinn Sabrina , Schnell Melanie 
Published: January 2019

AbstractThe aggregation of aromatic species is dictated by inter‐ and intramolecular forces. Not only is characterizing these forces in aromatic growth important for understanding grain formation in the interstellar medium, but it is also imperative to comprehend biological functions. We report a combined rotational spectroscopic and quantum‐chemical study on three homo‐dimers, comprising of diphenyl ether, dibenzofuran, and fluorene, to analyze the influence of structural flexibility and the presence of heteroatoms on dimer formation. The structural information obtained shows clear similarities between the dimers, despite their qualitatively different molecular interactions. All dimers are dominated by dispersion interactions, but the dibenzofuran dimer is also influenced by repulsion between the free electron pairs of the oxygen atoms and the π‐clouds. This study lays the groundwork for understanding the first steps of molecular aggregation in systems with aromatic residues.
Reverse Arene Sandwich Structures Based upon π‐Hole⋅⋅⋅[MII] (d8 M=Pt, Pd) Interactions, where Positively Charged Metal Centers Play the Role of a Nucleophile
Authors: Rozhkov Anton V. , Krykova Mariya A. , Ivanov Daniil M. , Novikov Alexander S. , Sinelshchikova Anna A. , Volostnykh Marina V. , Konovalov Mikhail A. , Grigoriev Mikhail S. , Gorbunova Yulia G. , Kukushkin Vadim Yu. 
Published: January 2019

AbstractThe complexes [Pt(tpp)] (H2tpp=tetraphenylporphyrin), [M(acac)2] (M=Pd, Pt, Hacac=acetylacetone), and [Pd(ba)2] (Hba=benzoylacetone) were co‐crystallized with highly electron‐deficient arene systems to form reverse arene sandwich structures built by π‐hole⋅⋅⋅[MII] (d8M=Pt, Pd) interactions. The adduct [Pt(tpp)]⋅2 C6F6 is monomeric, whereas the diketonate 1:1 adducts form columnar infinity 1D‐stack assembled by simultaneous action of both π‐hole⋅⋅⋅[MII] and C⋅⋅⋅F interactions. The reverse sandwiches are based on noncovalent interactions and calculated ESP distributions indicate that in π‐hole⋅⋅⋅[MII] contacts, [MII] plays the role of a nucleophile.
General Cyclopropane Assembly by Enantioselective Transfer of a Redox‐Active Carbene to Aliphatic Olefins
Authors: Montesinos‐Magraner Marc , Costantini Matteo , Ramírez‐Contreras Rodrigo , Muratore Michael E. , Johansson Magnus J. , Mendoza Abraham 
Published: January 2019

AbstractAsymmetric cyclopropane synthesis currently requires bespoke strategies, methods, substrates, and reagents, even when targeting similar compounds. This approach slows down discovery and limits available chemical space. Introduced herein is a practical and versatile diazocompound and its performance in the first unified asymmetric synthesis of functionalized cyclopropanes. The redox‐active leaving group in this reagent enhances the reactivity and selectivity of geminal carbene transfer. This effect allowed the asymmetric cyclopropanation of various olefins, including unfunctionalized aliphatic alkenes, that enables the three‐step total synthesis of (−)‐dictyopterene A. This unified synthetic approach delivers high enantioselectivities that are independent of the stereoelectronic properties of the functional groups transferred. Our results demonstrate that orthogonally differentiated diazocompounds are viable and advantageous equivalents of single‐carbon chirons.
Application of the thermal energy storage concept to novel epoxy–short carbon fiber composites
Authors: Dorigato A. , Fredi G. , Pegoretti A. 
Published: January 2019

ABSTRACTFor the first time, multifunctional epoxy–short carbon fiber reinforced composites suitable for thermal energy storage technology were developed. Paraffin microcapsules (MC) and short carbon fibers (CFs) were added at different relative amounts to an epoxy matrix, and the microstructural and thermomechanical properties of the resulting materials were investigated. Scanning electron microscopy images of the composites showed a uniform distribution of the capsules within the matrix, with a rather good interfacial adhesion, while the increase in the polymer viscosity at elevated CF and MC amounts caused an increase in the void content. Differential scanning calorimetry tests revealed that melting enthalpy values (up to 60 J/g) can be obtained at high MC concentrations. The mixing and thermal curing of the composites did not lead to breakage of the capsules and to the consequent leakage of the paraffin out of the epoxy matrix. The thermal stability of the prepared composites is not negatively affected by the MC addition, and the temperatures at which the thermal degradation process begins were far above the curing or service temperature of the composites. Flexural and impact tests highlighted that the presence of MC reduces the mechanical properties of the samples, while CF positively contributes to retaining the original stiffness and mechanical resistance. © 2019 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2019, 136, 47434.
Property enhancement of poly(butylene succinate)/poly(ethyleneglycol‐co‐cyclohexane‐1,4‐dimethanolterephthalate) blends via high‐speed extrusion and in situ fibrillation
Authors: Fan Mao , Zhou Mi , Deng Sha , Chen Feng , Zhang Qin , Fu Qiang 
Published: January 2019

ABSTRACTIn the current work, poly(butylene succinate)(PBS)/poly(ethylene glycol‐co‐cyclohexane‐1,4‐dimethanolterephthalate) (PETG) blends were first prepared by high‐speed extrusion melt processing, and the dependence of the dispersed morphology(phase size) was investigated as function of screw speed. Then, the prepared blends were subjected to a “melt extrusion‐uniaxial cold stretching” process to convert the dispersed phase into fibrillar structure, and the diameter change and property enhancement of PBS/PETG blends were further studied. It was found, at fixed ratio of PBS/PETG = 80/20 (wt/wt), the diameters of the PETG was changed from 2.25, 1.29, 1.11, 0.89 μm to 1.13, 0.64, 0.50, 0.38 μm, as increasing the screw speed from 150, 500, 700 rpm to 900 rpm, respectively. In addition, increasing the extrusion speed is favorable not only for smaller but more uniform dispersed phase particles, thus leading to finer microfibrils with narrower diameter distribution after cold stretching. As a result, the yield strength of PBS could be improved from 25.6 to 39.8 MPa for blend obtained via high‐speed extrusion and stretching. Our work is important for the preparation of polymer blends with improved property. © 2019 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2019, 136, 47549.
Cross‐layer security design for encrypted CPS based on modified security signalling game
Authors: Shen Jiajun , Feng Dongqin 
Published: January 2019

AbstractRecent years have witnessed increasing cyber and physical attacks against encrypted cyber‐physical system (CPS) and the ensuing catastrophic consequences. A modified security signaling game (MSSG) model is proposed for capturing attack‐defense interactions and analyzing the cross‐layer security of encrypted CPS. Cyber real‐time performance and physical control performance are both considered in cross‐layer utility function. Theorems concerning the existence of pure‐strategy and mixed‐strategy perfect Bayesian Nash equilibrium (PBNE) are provided, based on which a cross‐layer security design algorithm is proposed for defender's optimal strategy against potential attacks. A numerical case is studied with the effectiveness of our method being proved.
Molecular dynamics insights into protein‐glycosaminoglycan systems from microsecond‐scale simulations
Authors: Bojarski Krzysztof K. , Sieradzan Adam K. , Samsonov Sergey A. 
Published: January 2019

AbstractHeparin is a key player in cell signaling via its physical interactions with protein targets in the extracellular matrix. However, basic molecular level understanding of these highly biologically relevant intermolecular interactions is still incomplete. In this study, for the first time, microsecond‐scale MD simulations are reported for a complex between fibroblast growth factor 1 and heparin. We rigorously analyze this molecular system in terms of the conformational space, structural, energetic, and dynamic characteristics. We reveal that the conformational selection mechanism of binding denotes a recognition specificity determinant. We conclude that the length of the simulation could be crucial for evaluation of some of the analyzed parameters. Our data provide novel significant insights into the interactions in the fibroblast growth factor 1 complex with heparin, in particular, and into the physical‐chemical nature of protein‐glycosaminoglycan systems in general, which have potential applicability for biomaterials development in the area of regenerative medicine.
Proposal for a new classification for perihilar cholangiocarcinoma based on tumour depth
Authors: Shinohara K , Ebata T , Shimoyama Y , Nakaguro M , Mizuno T , Matsuo K , Nagino M 
Published: January 2019

Abstract

Background
The T system for distal cholangiocarcinoma has been revised from a layer-based to a depth-based approach in the current American Joint Committee on Cancer (AJCC) classification. In perihilar cholangiocarcinoma, tumour depth in the staging scheme has not yet been addressed. The aim of this study was to propose a new T system using measured tumour depth in perihilar cholangiocarcinoma.

Methods
Patients who underwent hepatectomy for perihilar cholangiocarcinoma between 2001 and 2014 were reviewed retrospectively. The vertical distance between the top of the tumour and deepest invasive cells was measured as invasive tumour thickness (ITT) by two independent pathologists. Log rank statistics were used to determine cut-off points, and the concordance (C) index was used to assess survival discrimination of each T system.

Results
ITT was measurable in all 440 patients, with a median value of 6·0 (range 0–45) mm. The median difference in ITT between observers was 0·6 (range 0–20) mm. Cut-off points for prognosis were 1, 5 and 8 mm. Five-year survival decreased with increasing ITT (P &lt; 0·001): 67 per cent for ITT less than 1 mm (25 patients), 54·9 per cent for ITT 1 mm and over to less than 5 mm (138 patients), 43·4 per cent for ITT 5 mm and over to less than 8 mm (118 patients), and 32·2 per cent for ITT 8 mm and over (159 patients). The C-index of this classification was comparable to that of the current AJCC T classification (0·598 versus 0·589).

Conclusion
ITT is a reliable approach for making a depth assessment in perihilar cholangiocarcinoma. A four-tier ITT classification with cut-off points of 1, 5 and 8 mm is an adequate alternative to the current layer-based T classification.
Validation of an analytical method to quantify the permeation and penetration of flurbiprofen into human pharynx tissue
Authors: Turner Rob , Wevrett Sean Robert , Edmunds Suzanne , Brown Marc , Atkinson Robert , Shea Tim 
Published: January 2019

AbstractThe aim of this investigation was to develop receiver and extraction fluids, and subsequently validate an analytical method to quantify the permeation and penetration of flurbiprofen into human pharynx tissue using a Franz diffusion cell. The solubility and stability of flurbiprofen in a suitable receiver fluid, and a suitable extraction method and fluid to recover and quantitate flurbiprofen from human pharynx tissue, were investigated using high‐performance liquid chromatography (HPLC). The potential interference of human pharynx tissue in the receiver fluid was also investigated. The HPLC analytical method was successfully validated according to current guidelines. The final receiver fluid demonstrated sufficient solubility and stability, and the extraction method and fluid resulted in >95% recovery of flurbiprofen following exposure to human pharynx tissue. The lower limit of quantitation of flurbiprofen was 0.045 μg/mL in both the receiver and extraction fluids. There was no interference of the human pharynx tissue with the HPLC method. This investigation validated an analytical method for quantitating flurbiprofen, and determined a suitable receiver fluid and extraction method and fluid, which can be used to investigate the permeation and penetration of flurbiprofen through human pharynx tissue using the Franz diffusion cell method.