bluuebunny/crossref_metadata_2025_split huggingface dataset:
Nonleaching Antibacterial Concept Demonstrated by In Situ Construction of 2D Nanoflakes on Magnesium
Authors: Wang Guomin , Jiang Wenjuan , Mo Shi , Xie Lingxia , Liao Qing , Hu Liangsheng , Ruan Qingdong , Tang Kaiwei , Mehrjou Babak , Liu Mengting , Tong Liping , Wang Huaiyu , Zhuang Jie , Wu Guosong , Chu Paul K. 
Published: October 2019

AbstractIn bone implants, antibacterial biomaterials with nonleaching surfaces are superior to ones based on abrupt release because systemic side effects arising from the latter can be avoided. In this work, a nonleaching antibacterial concept is demonstrated by fabricating 2D nanoflakes in situ on magnesium (Mg). Different from the conventional antibacterial mechanisms that depend on Mg2+ release and pH increase, the nanoflakes exert mechanical tension onto the bacteria membranes to destroy microorganisms on contact and produce intracellular stress via physical interactions, which is also revealed by computational simulations. Moreover, the nanoflake layer decelerates the corrosion process resulting in mitigated Mg2+ release, weaker alkalinity in the vicinity, and less hydrogen evolution, in turn inducing less inflammatory reactions and ensuring the biocompatibility as confirmed by the in vivo study. In this way, bacteria are killed by a mechanical process causing very little side effects. This work provides information and insights pertaining to the design of multifunctional biomaterials.
Enhanced Thermoelectric and Mechanical Properties in Yb0.3Co4Sb12 with In Situ Formed CoSi Nanoprecipitates
Authors: Qin Dandan , Wu Haijun , Cai Songting , Zhu Jianbo , Cui Bo , Yin Li , Qin Haixu , Shi Wenjing , Zhang Yang , Zhang Qian , Liu Weishu , Cao Jian , Pennycook Stephen J. , Cai Wei , Sui Jiehe 
Published: October 2019

AbstractFilled Skutterudites are one group of the most promising thermoelectric materials in real power generation applications. Herein, homogeneously dispersed multiscale CoSi nanostructures are successfully embedded into grains of the classic skutterudite system, Yb0.3Co4Sb12, by the in situ precipitation method. Such nanoprecipitates contribute much to the synergistic enhancement of thermoelectric and mechanical properties. On one hand, by the fine deployment of multiscale CoSi nanoparticles, the lattice thermal conductivity is significantly depressed almost to the theoretical limit because of the disrupted propagation of the heat‐carrying phonons at phase boundaries. On the other hand, low‐energy electrons are effectively screened due to the energy filtering effect by the interfacial potential barrier between the CoSi nanoprecipitate and the matrix, resulting in an enhanced power factor. Taken together, an enhanced peak ZT value of ≈1.5 at 873 K for the Yb0.3Co4Sb12/0.05CoSi composite is obtained with a high average ZT ≈0.95 between 300 and 873 K through decoupling the electrical and thermal transport parameters. Moreover, such a microstructure with multiscale CoSi nanoparticles shows significantly improved mechanical properties owing to particle hardening, making it more competitive for practical applications.
Fifty‐year history of biliary surgery
Authors: Nagino Masato 
Published: October 2019

AbstractThere has been enormous progress in the surgical treatment of biliary tract cancers in the past 50 years. In preoperative management, biliary drainage methods have changed from percutaneous transhepatic biliary drainage to endoscopic nasobiliary drainage, while the advent of multidetector‐row computed tomography in imaging diagnostics now enables visualization of three‐dimensional anatomy, extent of cancer progression, and hepatic segment volume. Portal vein embolization has also greatly improved the safety of extended hepatectomy, and indication of extended hepatectomy can now be objectively determined with a combination of the indocyanine green test and computed tomography volumetry. In terms of surgery, combined resection and reconstruction of the portal vein and/or hepatic artery can now be safely carried out at specialized centers. Further, long‐term survival can be attained with combined vascular resection if R0 resection can be achieved, even in locally advanced cancer. Hepatopancreatoduodenectomy, combined major hepatectomy with pancreatoduodenectomy, should be aggressively carried out for laterally advanced cholangiocarcinoma, whereas its indication for advanced gallbladder cancer should be carefully evaluated. Japanese surgeons have made a significant contribution to the progression of extended surgeries such as combined vascular resection and hepatopancreatoduodenectomy for biliary tract cancer.
Emotional functioning among children with neurofibromatosis type 1 or Noonan syndrome
Authors: McNeill Alana M. , Hudock Rebekah L. , Foy Allison M. H. , Shanley Ryan , Semrud‐Clikeman Margaret , Pierpont Mary Ella , Berry Susan A. , Sommer Katherine , Moertel Christopher L. , Pierpont Elizabeth I. 
Published: October 2019

AbstractWhile neurofibromatosis type 1 (NF1) and Noonan syndrome (NS) are clinically distinct genetic syndromes, they have overlapping features because they are caused by pathogenic variants in genes encoding molecules within the Ras‐mitogen‐activated protein kinase signaling pathway. Increased risk for emotional and behavioral challenges has been reported in both children and adults with these syndromes. The current study examined parent‐report and self‐report measures of emotional functioning among children with NF1 and NS as compared to their unaffected siblings. Parents and children with NS (n = 39), NF1 (n = 39), and their siblings without a genetic condition (n = 32) completed well‐validated clinical symptom rating scales. Results from parent questionnaires indicated greater symptomatology on scales measuring internalizing behaviors and symptoms of attention deficit hyperactivity disorder (ADHD) in both syndrome groups as compared with unaffected children. Frequency and severity of emotional and behavioral symptoms were remarkably similar across the two clinical groups. Symptoms of depression and anxiety were higher in children who were also rated as meeting symptom criteria for ADHD. While self‐report ratings by children generally correlated with parent ratings, symptom severity was less pronounced. Among unaffected siblings, parent ratings indicated higher than expected levels of anxiety. Study findings may assist with guiding family‐based interventions to address emotional challenges.
Phenotypic expansion of POFUT1 loss of function mutations in a disorder featuring segmental dyspigmentation with eczematous and folliculo‐centric lesions
Authors: Atzmony Lihi , Zaki Theodore D. , Antaya Richard J. , Choate Keith A. 
Published: October 2019

AbstractAppearance of mosaic disorders in thin Blaschko lines suggests that somatic mutations in keratinocyte precursors underlie their pathogenesis. Germline heterozygous mutations in POFUT1 gene cause Dowling–Degos disease (DDD), a skin disease that features flexural reticulated hyperpigmentation and follicular‐based lesions. POFUT1 mosaicism has not been described to date. Here, we describe a 9‐year‐old female with segmental hyper‐ and hypopigmented patches with overlying eczematous plaques and follicular papules. Employing paired whole exome sequencing of saliva and keratinocytes isolated from affected skin, we found a novel germline heterozygous POFUT1 deletion causing frameshift and premature codon termination and somatic copy‐neutral loss of heterozygosity on chromosome 20 encompassing POFUT1. Expression levels of POFUT1 as well as other key regulators of the notch signaling pathway—NOTCH1, NOTCH2, and HES1—were reduced in affected keratinocytes compared with normal keratinocytes. Our findings provide the first evidence of POFUT1 postzygotic mutation and a phenotypic expansion of POFUT1 loss of function mutations. We show that a recessive loss of function mutation in POFUT1 produces a distinct clinical presentation with features (e.g., dermatitis) that are absent in the generalized form of DDD. This study demonstrates how analysis of mosaic disorders can reveal unexpected phenotypes for known genes.
Modifications of Electron States, Magnetization, and Persistent Current in a Quantum Dot by Controlled Curvature
Authors: Pereira Luís Fernando C. , Andrade Fabiano M. , Filgueiras Cleverson , Silva Edilberto O. 
Published: October 2019

AbstractThe thin‐layer quantization procedure is used to study the physical implications due to curvature effects on a quantum dot in the presence of an external magnetic field. Among the various physical implications due to the curvature of the system, the absence of the state is the most relevant one. This absence affects the Fermi energy and consequently the thermodynamic properties of the system. In the absence of magnetic fields, it is verified that the rotational symmetry in the lateral confinement is preserved in the electronic states of the system and its degeneracy concerning the harmonicity of the confining potential is broken. In the presence of a magnetic field, however, the energies of the electronic states in a quantum dot with curvature are greater than those obtained for a quantum dot in a flat space, and the profile of degeneracy changes when the field is varied. It is shown that the curvature of the surface modifies the number of subbands occupied in the Fermi energy. In the study of both magnetization and persistent currents, it is observed that Aharonov–Bohm‐type oscillations are present, whereas de Haas–van Alphen‐type oscillations are not well defined.
Coordinative Chain Transfer Polymerization of Butadiene with Functionalized Aluminum Reagents
Authors: Göttker‐Schnetmann Inigo , Kenyon Philip , Mecking Stefan 
Published: October 2019

AbstractFunctionalized aluminum alkyls enable effective coordinative chain transfer polymerization with selective chain initiation by the functionalized alkyl. (ω‐Aminoalkyl)diisobutylaluminum reagents (12 examples studied) obtained by hydroalumination of α‐amino‐ω‐enes with diisobutylaluminum hydride promote the stereoselective catalytic chain growth of butadiene on aluminum in the presence of Nd(versatate)3, Cp*2Nd(allyl), or Cp*2Gd(allyl) precatalysts and [PhNMe2H+]/[B(C6F5)4−]. Carbazolyl‐ and indolylaluminum reagents result in efficient molecular weight control and chain initiation by the aminoalkyl rather than the isobutyl substituent bound to aluminum. As confirmed for (3‐(9H‐carbazol‐9‐yl)propyl)‐initiated polybutadiene (PBD), for example, by deuterium quenching studies, polymer chain transfer by β‐hydride transfer is negligible in comparison to back‐transfer to aluminum.
Effiziente organokatalytische Dehydrierung von Amminboran
Authors: Hasenbeck Max , Becker Jonathan , Gellrich Urs 
Published: October 2019

AbstractWir berichten die effiziente Dehydrierung von Amminboran durch sterisch anspruchsvolle Pyridone als Organokatalysatoren. Mit 6‐tert‐Butylthiopyridon wurde eine Wechselzahl (Turnover Frequency, TOF) von 88 h−1 erreicht. Experimentelle mechanistische Untersuchungen, gestützt durch DLPNO‐CCSD(T) Rechnungen, deuten auf eine Protonierung der B‐H‐Bindungen durch den in der Mercaptopyridinform vorliegenden Katalysator als ersten Schritt des Katalysezyklus hin. Das durch diese initiale Protonierung gebildete Intermediat wurde NMR‐spektroskopisch detektiert und die Molekülstruktur einer Surrogat‐Verbindung mittels Einkristall‐Röntgendiffraktometrie ermittelt. Ein intramolekularer Protonentransfer von der NH3‐Gruppe zu dem Pyridinring in diesem Intermediat und das gleichzeitige Brechen der S‐B‐Bindung regeneriert das Thiopyridon und schließt somit einen katalytischen Zyklus. Dieser Schritt kann als eine anorganische Retro‐En‐Reaktion beschrieben werden.
Katalytische Difunktionalisierung von nichtaktivierten Alkenen mit reaktionsträgem Hexamethyldisilan durch Neubildung von Silyliumionen
Authors: Wu Qian , Roy Avijit , Irran Elisabeth , Qu Zheng‐Wang , Grimme Stefan , Klare Hendrik F. T. , Oestreich Martin 
Published: October 2019

AbstractEs wird über eine metallfreie, intermolekulare syn‐Addition von Hexamethyldisilan an einfache Alkene berichtet. Der Katalysezyklus wird durch die Übertragung einer Methylgruppe des Disilans auf eine Silyliumion‐artige Zwischenstufe eingeleitet und aufrechterhalten, was der (Neu)bildung des Silyliumion‐Katalysators gleichkommt. Das Hauptmerkmal der Reaktionssequenz ist die Spaltung der Si‐Si‐Bindung im Zuge einer 1,3‐Silylwanderung von Silicium nach Kohlenstoff. Eine zentrale Zwischenstufe der Katalyse wurde durch Röntgenbeugung strukturell charakterisiert, und der berechnete Reaktionsmechanismus steht in vollständigem Einklang mit den experimentellen Befunden.
Festkörper‐ und Gasphasenstrukturen sowie energetische Eigenschaften des gefährlichen Methyl‐ und Fluormethylnitrats
Authors: Reichel Marco , Krumm Burkhard , Vishnevskiy Yury V. , Blomeyer Sebastian , Schwabedissen Jan , Stammler Hans‐Georg , Karaghiosoff Konstantin , Mitzel Norbert W. 
Published: October 2019

AbstractEine verbesserte Synthese für den einfachsten Salpetersäureester, Methylnitrat, und eine neue Synthese für Fluormethylnitrat benutzen die Salzeliminierung der entsprechenden Iodmethane mit Silbernitrat. Beide Verbindungen wurden spektroskopisch und durch Strukturbestimmung im Festkörper von in situ erzeugten Kristallen mittels Röntgenbeugung sowie in der Gasphase mittels Elektronenbeugung identifiziert. Die Fluorierung führt zu Strukturen mit kürzeren C‐O‐ und N‐O‐Bindungen, hat eine energetisch destabilisierende Wirkung und erhöht die Reibungsempfindlichkeit, verringert aber die Detonationsleistung.
Supramolecular Photothermal Effects: A Promising Mechanism for Efficient Thermal Conversion
Authors: Zhao Luyang , Liu Yamei , Xing Ruirui , Yan Xuehai 
Published: October 2019

AbstractSupramolecular assemblies have been very successful in regulating the photothermal conversion efficiency of organic photothermal materials in a simple and flexible way, compared with conventional molecular synthesis. In these assemblies, it is the inherent physiochemical mechanism that determines the photothermal conversion, rather than the assembly strategy. This Minireview summarizes supramolecular photothermal effects, which refer to the unique features of supramolecular chemistry for regulating the photothermal conversion efficiency. Emphasis is placed on the mechanisms of how self‐assembly affects the photothermal performance. The supramolecular photothermal effects on various types of light‐harvesting species are discussed in detail. The timely interpretation of supramolecular photothermal effects is promising for the future design of the photothermal materials with high efficiency, precision, and multiple functionalities for a wide array of applications.
Sacral plexus catheter analgesia in a patient with traumatic sacral fractures and Tarlov cysts
Authors: Ireland E. , Womack J. , Foley E. 
Published: October 2019

SummaryWe report the use of a sacral plexus catheter for continuous local anaesthetic infusion in a patient with a unilateral sacral ala fracture following a fall from a horse. Although sacral plexus blockade has been well described for lower limb surgery, an ultrasound‐guided continuous catheter technique for conservatively managed fractures has not been described. Despite appropriate oral analgesia, the patient reported severe pain, particularly in the right gluteal region, which meant she was unable to sit upright or take deep breaths. A sacral plexus catheter was inserted with ultrasound guidance and an initial bolus of 30 ml levobupivicaine 0.25% was delivered followed by infusion of 8 ml.h−1 levobupivicaine 0.125%. Daily follow‐up and assessment were provided by the acute pain team. We judged the procedure to be a success as measured by an improvement in mobilisation, deep breathing, cough and patient satisfaction.
Cavitation Clusters in Lipid Systems: The Generation of a Bifurcated Streamer and the Dual Collapse of a Bubble Cluster
Authors: Birkin Peter R. , Martin Hannah L. , Youngs Jack J. , Truscott Tadd T. , Merritt Andrew S. , Elison Ethan J. , Martini Silvana 
Published: October 2019

AbstractSeveral studies have reported the use of high‐intensity ultrasound (HIU) to induce the crystallization of lipids. The effect that HIU has on lipid crystallization is usually attributed to the generation of cavities but acoustic cavitation has never been fully explored in lipids. The dynamics of a particular cavitation cluster next to a piston like emitter (PLE) in an oil was investigated in this study. The lipid systems, which are important in food processing, are studied with high‐speed camera imaging, laser scattering, and acoustic pressure measurements. A sequence of stable clusters was noted. In addition, a bifurcated streamer was detected, which exists within a sequence of clusters. This is shown to originate from two clusters on the PLE tip oscillating with a 180° phase shift in time with respect to one another. Finally, the collapse phase of the cluster is shown to involve a rapid (~10 μs) two‐stage process. These results show that the dynamics of cluster formation and collapse is driven by HIU power levels and might have implications in lipid sonocrystallization.
High‐performance composite photocatalytic membrane based on titanium dioxide nanowire/graphene oxide for water treatment
Authors: Yu Zongxue , Zeng Haojie , Min Xia , Zhu Xianfeng 
Published: October 2019

ABSTRACTIn this study, a novel dopamine‐modified TiO2 nanowire (NW)‐intercalated graphene‐oxide‐based photocatalytic (NWC) membrane was prepared by vacuum‐assisted filtration using a commercial cellulose acetate membrane as a support layer. At the same time, compared with the synthesized reduced graphene‐oxide/polydopamine/TiO2 nanoparticle composite (NPC) membrane, it was found that the NWC membrane has high water flux (273 L m−2 h−1) and removal rate (above 98%) on the dye‐oil emulsion. After 5 cycles of experiments, the NWC membrane maintained a relatively stable permeation flux and removal rate, which was significantly better than the NPC membrane. The results showed that the NWC membrane had a more uniform distribution of TiO2 NW, and had better antifouling ability, recyclability, and photocatalytic performance than NPC membrane. In summary, the NWC photocatalytic membrane of this study shows excellent water purification potential and provides a new path for photocatalytic water treatment. © 2019 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2020, 137, 48488.
Preparation of chitosan‐modified core–shell SiO2‐acidic polymer multiple crosslinked membranes
Authors: Shang Jing‐Ran , Zhong Shuang‐Ling , Zhao Ye , Wang Bin , Gao Yu‐Shan , Xiang Wen‐Tao , Cui Xue‐Jun 
Published: October 2019

ABSTRACTThis article prepares and studies a series of chitosan‐modified core–shell SiO2‐acidic polymer multiple crosslinked membranes (modified membranes). The preparation process is simple, low cost, and environmentally friendly. The multiple crosslinking enhances the thermal stability and mechanical strength of membranes. TGA shows that the 10% weight loss temperatures of modified membranes are above 300 °C. Compared with water uptake, the methanol absorption of modified membranes is lower and decreases with increasing methanol concentration, which is very beneficial to their use in direct‐methanol fuel cells. The lowest methanol diffusion coefficient of the modified membrane is 4.56 × 10−8 cm2 s−1, which is only about 1/50th of that of Nafion117. In addition, the membranes exhibit feasible proton conductivity and higher selectivity than Nafion117. These results indicate that the chitosan‐modified core–shell SiO2‐acidic polymer multiple crosslinked membranes have potential applications in direct‐methanol fuel cells. © 2019 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2020, 137, 48494.
In situ dispersion and polymerization of polyethylene cellulose nanocrystal‐based nanocomposites
Authors: Hendren Keith D. , Baughman Travis W. , Deck Paul A. , Foster E. Johan 
Published: October 2019

ABSTRACTThis study describes a novel method of forming a nanocomposite comprising cellulose nanocrystals (CNCs) as the reinforcing filler and a high‐density polyethylene (PE) matrix. The method involves covalent attachment of a metallocene catalyst, 1,1′‐bis(bromodimethylsilyl)zirconocene dibromide 1, to the hydroxyl‐rich surfaces of the CNCs and subsequent slurry polymerization with excess alumoxane (MMAO‐12) as the cocatalyst. Polymerization proceeds with activities reaching 500 kg mol−1 atm−1 h−1, while the CNCs are simultaneously dispersed to afford robust, well‐dispersed nanocomposites. Films of these composites (about 7‐vol % CNC) showed excellent dispersal of the filler (optically translucent; no CNC aggregation observed by atomic force microscopy). The composites (about 7‐vol % CNC) also revealed an increase in Young's modulus (10–100%) and comparable yield strength relative to commercially produced PEs. The experimental simplicity of this approach suggests that our method could be scaled beyond the present laboratory scale and extended to reinforce other polyolefin grades. © 2019 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2020, 137, 48500.
A simple and effective approach to produce tubular polysaccharide‐based hydrogel scaffolds
Authors: Bombaldi de Souza Fernanda Carla , Camasão Dimitria Bonizol , Bombaldi de Souza Renata Francielle , Drouin Bernard , Mantovani Diego , Moraes Ângela Maria 
Published: October 2019

ABSTRACTThe production of porous tubular scaffolds is of great interest in the field of tissue engineering, given the existence of several tubular structures in the human body. In this work, a methodology was developed for the fabrication of tubular‐shaped scaffolds based on the casting of polymeric solutions by controlled crosslinking mediated by a semipermeable cast. The fabrication of hydrogel tubular scaffolds from chitosan–pectin polymeric mixtures (tCh‐P, 3% w/v) was performed to attest the feasibility of the technique. Tubular structures with about 4.15 mm internal diameter and 1.55 mm wall thickness were produced. The structures are highly porous, presenting interconnected pores with average diameter of about 360 μm. Seeding of human smooth muscle cells on the material was successfully achieved by using collagen gel to facilitate cell migration and retention inside the structure of the scaffold. The methodology herein proposed was successfully validated for the production of tubular constructs, opening new perspectives for the fabrication of matrices based on polymers that are passive of crosslinking with small molecules. Besides being an interesting approach to produce tubular scaffolds, this methodology can be considered an useful platform to obtain materials for drug screening and diagnostic studies. © 2019 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2020, 137, 48510.
Influence of remote plasma on PEDOT:PSS‐coated carbon felt for improved activity of glucose oxidase
Authors: Kahoush May , Behary Nemeshwaree , Cayla Aurélie , Mutel Brigitte , Guan Jinping , Nierstrasz Vincent 
Published: October 2019

ABSTRACTIncreasing wettability of carbon felts is an important strategy to improve their efficiency in bio‐electrochemical applications. Herein, influence of cold remote plasma (N2 + O2) treatment on surface properties of carbon felts with poly(3,4‐ethylenedioxythiophene) polystyrene sulfonate (PEDOT:PSS) coating was tested, aiming to improve immobilizing of glucose oxidase enzyme (GOx). Spectra of N 1s and O 1s confirmed the integration of carbonyl and ether as well as amide and amine groups on bare carbon fiber surface, while on coated fibers, carbonyl groups were pre‐dominant. S 2p spectra confirmed oxidation of PEDOT:PSS coating with reduction of (S−) compared to (SO3−) group. GOx immobilized on different samples showed highest activity for PEDOT:PSS coating subjected to plasma with 2% O2, maintaining up to 60% after immobilization, and 37% of its activity after six cycles for some samples. Enzymes immobilized on samples without plasma treatment lost their activity after four cycles. © 2019 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2020, 137, 48521.