bluuebunny/crossref_metadata_2025_split huggingface dataset:
Synthesis, Characterization, and Reactivity of Functionalized Trinuclear Iron–Sulfur Clusters – A New Class of Bioinspired Hydrogenase Models
Authors: Kaiser Manuel , Knör Günther 
Published: August 2015

AbstractThe air‐ and moisture‐stable iron–sulfur carbonyl clusters Fe3S2(CO)7(dppm) (1) and Fe3S2(CO)7(dppf) (2) carrying the bisphosphine ligands bis(diphenylphosphanyl)methane (dppm) and 1,1′‐bis(diphenylphosphanyl)ferrocene (dppf) were prepared and fully characterized. Two alternative synthetic routes based on different thionation reactions of triiron dodecacarbonyl were tested. The molecular structures of the methylene‐bridged compound 1 and the ferrocene‐functionalized derivative 2 were determined by single‐crystal X‐ray diffraction. The catalytic reactivity of the trinuclear iron–sulfur cluster core for proton reduction in solution at low overpotential was demonstrated. These deeply colored bisphosphine‐bridged sulfur‐capped iron carbonyl systems are discussed as promising candidates for the development of new bioinspired model compounds of iron‐based hydrogenases.
Doped Framework Iron Hydroxyl Phosphate as Photocatalyst for Hydrogen Production from Water/Methanol Mixtures
Authors: Serra Marco , Baldovi Herme G. , Alvaro Mercedes , Garcia Hermenegildo 
Published: August 2015

AbstractIn the search for novel photocatalysts for hydrogen production and with the α‐Fe2O3 photoelectrocatalyst as a recent precedent, we report herein the preparation, semiconductor properties and photocatalytic activity of metal‐doped (0.1–5 wt.‐% loading) iron hydroxyl phosphate (FeP). X‐ray diffraction analyses of FeP samples subjected to extended photocatalytic irradiation showed the stability of this framework phosphate under photocatalytic conditions. Doping increased the photocatalytic efficiency of FeP for all dopants, with the optimal doping level between 0.1 and 1 %. Under the optimized conditions (Cr at 1 % doping), the photocatalytic activity of FeP reached a hydrogen production rate of 35.82 μmol gFe–1 in the absence of platinum as co‐catalyst. The conduction flat band potential was estimated by photocurrent measurements or impedance spectroscopy to be 0.1 eV versus NHE and the charge carrier density 2.6 × 1020 carriers cm–3. Transient absorption spectroscopy revealed a transient species decaying on the microsecond timescale characterized by a broad band spanning 300–750 nm. This transient was attributed to the charge‐separated state. These results are promising for the development of novel photocatalytic materials based on framework metal phosphate.
Toxicity and Protective Effects of Cerium Oxide Nanoparticles (Nanoceria) Depending on Their Preparation Method, Particle Size, Cell Type, and Exposure Route
Authors: Gagnon Jacinthe , Fromm Katharina M. 
Published: August 2015

AbstractNanoceria (cerium oxide nanoparticles) toxicity is currently a concern because of its use in motor vehicles in order to reduce carbon monoxide (CO), nitrogen oxides (NOx), and hydrocarbons in exhaust gases. In addition, many questions arise with respect to its biomedical applications exploiting its potential to protect cells against irradiation and oxidative stress. Indeed, toxicology studies on nanoceria report results that seem contradictory, demonstrating toxic effects in some studies, protective effects in others, and sometimes little or no effect at all. The variability in the experimental setups and particle characterization makes these studies difficult to compare and the toxicity of newly developed nanoceria materials challenging to predict. This microreview aims to compare the toxicity of nanoceria in terms of preparation method, particle size, concentration, host organism, and exposure method.
Cytotoxicity and Structural Analyses of 2,2′‐Bipyridine‐, 4,4′‐Dimethyl‐2,2′‐bipyr­idine‐ and 2‐(2′‐Pyridyl)quinoxalineplatinum(II) Complexes
Authors: Pages Benjamin J. , Zhang Yingjie , Li Feng , Sakoff Jennette , Gilbert Jayne , Aldrich‐Wright Janice R. 
Published: August 2015

AbstractPlatinum anticancer complexes incorporating 2,2′‐bipyridine (bpy), 4,4′‐dimethyl‐2,2′‐bipyridine (44Me2bpy) or 2‐(2′‐pyridyl)quinoxaline (2pq) as polyaromatic ligands and the S,S or R,R isomer of 1,2‐diaminocyclohexane as ancillary ligands in the form [Pt(PL)(AL)]2+ have been synthesised and characterised. X‐ray diffraction was used to elucidate the structure and stacking behaviour of the complexes, revealing interesting properties that may impact their biological activity. Pulsed gradient spin‐echo NMR experiments elucidated the aggregation behaviour of these complexes in solution. The cytotoxicity of each complex was assessed against the L1210 murine leukaemia, HT29 human colon carcinoma and U87 human glioblastoma cell lines and compared to other complexes within this class. The complexes incorporating 44Me2bpy were found to be the most potent at inhibiting cell growth with IC50 values for the S,S isomer (0.13–0.5 μM) less than that for cisplatin (0.36–11 μM), oxaliplatin (0.9–1.8 μM) or carboplatin (>50 μM). Most complexes were found to be very effective against HT29 colon carcinoma cells.
A Strategy for the Triarylation of Pyrrolo­pyrimidines by Using Microwave‐Promoted Cross‐Coupling Reactions
Authors: Prieur Vanessa , Pujol M. Dolors , Guillaumet Gérald 
Published: August 2015

AbstractNew pyrrolo[2,3‐d]pyrimidines that have aryl groups at the 2‐, 4‐, and 6‐positions were prepared by the arylation reaction of 4‐chloro‐7‐methyl‐2‐(methylthio)‐6‐phenylpyrrolo[2,3‐d]pyrimidine (6) and the corresponding arylboronic acid under Suzuki–Miyaura conditions followed by a second arylation under Liebeskind–Srogl cross‐coupling conditions. A parallel study that began with the C‐2 chemoselective arylation of 6 under Liebeskind–Srogl conditions followed by a Suzuki–Miyaura coupling at C‐4 was carried out, and the results of each route were compared. All of the tranformations were performed under microwave irradiation.
Enantioselective Ring Opening of meso‐Epoxides with Silicon Tetrachloride Catalyzed by Pyridine N‐Oxides Fused with the Bicyclo[3.3.1]nonane Framework
Authors: Neniškis Algirdas , Stončius Sigitas 
Published: August 2015

AbstractThe synthesis of new chiral Lewis basic organocatalysts that contain pyridine N‐oxide moieties fused with the bicyclo[3.3.1]nonane framework is reported. The obtained pyridine N‐oxides were employed as catalysts in the enantioselective ring opening of meso‐epoxides with silicon tetrachloride. Derivative 1b endowed with two 2,4‐diaryl‐substituted pyridine N‐oxide moieties proved to be a particularly effective catalyst for desymmetrization of norbornene oxide 16i to furnish Wagner–Meerwein rearrangement product 20i in unprecedented 96 % ee. Difunctional congener 3, which is striped of the 4‐aryl substituents, exhibited moderate to high levels of asymmetric induction (47–88 % ee) with alicyclic epoxide substrates.
Complexations between Oxacalixcrowns and Secondary Ammonium Salts and ­Construction of an Oxacalixcrown‐Based [2]Rotaxane
Authors: Liu Hua , Hu Wen‐Jing , Liu Yahu A. , Li Jiu‐Sheng , Jiang Biao , Wen Ke 
Published: August 2015

AbstractPseudorotaxane type host–guest complex of a secondary ammonium salt and oxacalixcrown with the polyether linker as short as five ethylene glycol units was created. While an axle containing both ammonium and carbamate stations was installed in an oxacalixcrown‐6‐based [2]rotaxane through a threading‐followed‐by‐stoppering approach, translocation of the oxacalixcrown‐6 component of the [2]rotaxane from the secondary ammonium station to the carbamate station of the thread was achieved through blocking the amino moiety with a bulky Boc group.
A General Approach towards NH‐Pyr­azoles That Bear Diverse Fluoroalkyl Groups by Means of Fluorinated Iminium Salts
Authors: Schmitt Etienne , Landelle Grégory , Vors Jean‐Pierre , Lui Norbert , Pazenok Sergiy , Leroux Frédéric R. 
Published: August 2015

AbstractA new and general approach to important fluoroalkyl‐substituted pyrazoles has been developed. The approach is based on the use of fluoroalkyl amino reagents and their Lewis acid activation to form a fluoroalkyl iminium salt that acts as a formal “fluoroacyl transfer reagent”. Their interaction with readily available fluoroalkyl azines followed by spontaneous cyclization of the formed intermediates under acidic conditions leads to the formation of 3,5‐disubstituted pyrazoles. The reaction is extremely versatile, high yielding, and allows quick access to pyrazoles that bear two fluoroalkyl functionalities (identical or different). These compounds are otherwise difficult to prepare. The reaction is scalable and suitable for industrial production.
A Mild and General One‐Pot Synthesis of Densely Functionalized Diaryliodonium Salts
Authors: Qin Linlin , Hu Bao , Neumann Kiel D. , Linstad Ethan J. , McCauley Katelyenn , Veness Jordan , Kempinger Jayson J. , DiMagno Stephen G. 
Published: August 2015

AbstractDiaryliodonium salts are powerful and widely used arylating agents in organic chemistry. Here we report a scalable synthesis of densely functionalized diaryliodonium salts from aryl iodides under mild conditions. This two‐step, one‐pot process has remarkable functional group tolerance, is compatible with commonly employed acid‐labile protective group strategies, avoids heavy metal and transition metal reagents, and provides a direct route to stable precursors to PET imaging agents.
Lateral Flow Immunoassays – from Paper Strip to Smartphone Technology
Authors: Eltzov Evgeni , Guttel Sarah , Low Yuen Kei Adarina , Sinawang Prima Dewi , Ionescu Rodica E. , Marks Robert S. 
Published: August 2015

AbstractLateral flow immunoassays provide low cost, fast, portable and simple to use devices, with yes/no answers seen by the naked eye, that has found applications in agriculture, biomedicine, the environment, and food industries. Making these quantitative, via electrochemical or optical approaches, is the present day challenge, with a vision that one day, these will be connected to smartphone technologies, which exhibit a promising digital platform for point‐of‐care diagnostics, mobile healthcare and bioanalytical needs. These devices are fully automated and equipped with a high resolution camera, a powerful processor with high storage capacity, wireless connectivity, real‐time geo‐tagging, secure data management, and cloud computing.
An Electrochemical Sensor Based on Nitrogen‐doped Carbon Nanofiber for Bisphenol A Determination
Authors: Sun Jinying , Liu Yang , Lv Simin , Huang Zhirong , Cui Liao , Wu Tie 
Published: August 2015

AbstractIn this paper, bisphenol A was determined by electrochemical method at a nitrogen‐doped carbon nanofiber modified carbon paste electrode (NCNF/CPE) with high sensitivity and good selectivity. NCNF was obtained by a simple electrospinning followed by carbonization procedure, in which polyacrylonitrile (PAN) as precursor and nitrogen doping was realized by re‐utilizing the tail gas that produced in the thermal pretreatment process. Good reproducibility and high stability were obtained for BPA detection at NCNF modified CPE. Current response plotted with BPA concentration was linear in the range of 0.1–60 μM with LOD of 0.05 μM. The proposed electrochemical sensor was employed for BPA determination with satisfactory recoveries for real water samples, indicating the practical applicability of NCNF/CPE.
Measuring the Electrode Kinetics of Vitamin B2 at a Constant Time Window of a Square Wave Voltammetric Experiment
Authors: Mirceski Valentin , Smarzewska Sylwia , Guziejewski Dariusz 
Published: August 2015

AbstractThe electrode kinetics of vitamin B2 was measured at a constant scan rate of a square‐wave (SW) voltammetric experiment by recently introduced method based on alteration of the height (amplitude) of the SW potential pulses. The electrode reaction mechanism was analyzed in the light of the simplified model considering two‐electron one step surface electrode mechanism, as well as to more appropriate EE surface reaction pathway consisting of two successive one‐electron quasireversible reactions. Theoretical analysis indicated that the evolution of the voltammetric response under variation of the SW amplitude enables estimation of the rate determining step of the EE mechanism.
Integrated Porous Cathode made of Pure Perovskite Lanthanum Nickel Oxide for Nonaqueous Lithium–Oxygen Batteries
Authors: Wei Zhaohuan , Zhao Tianshou , Zhu Xingbao , An Liang , Tan Peng 
Published: August 2015

AbstractThe development of non‐carbon electrodes for nonaqueous lithium–oxygen batteries has become a recent focus as carbon electrodes were found to be unstable. Conventional non‐carbon electrodes are typically formed with a substrate/current collector, which will decrease the practical capacity. Here, we propose an integrated porous electrode made of LaNiO3 that does not require a substrate/current collector. The porous structure allows the formation of nanosized pores on the walls of microsized pores, which facilitates the transport of both oxygen and lithium ions. Importantly, all the surfaces of the porous structure are catalytically active for electrochemical reactions. Experimental results show that the adoption of the electrode in the battery enables a capacity of 1.064 mAh cm−2 at a current density of 0.05 mA cm−2. Furthermore, it is demonstrated that the battery can be cycled for at least 25 cycles at a fixed capacity of 0.3 mAh cm−2, and the electrode shows no degradation after the cycles.
A parallel monolithic algorithm for the numerical simulation of large‐scale fluid structure interaction problems
Authors: Eken Ali , Sahin Mehmet 
Published: August 2015

SummaryA novel parallel monolithic algorithm has been developed for the numerical simulation of large‐scale fluid structure interaction problems. The governing incompressible Navier–Stokes equations for the fluid domain are discretized using the arbitrary Lagrangian–Eulerian formulation‐based side‐centered unstructured finite volume method. The deformation of the solid domain is governed by the constitutive laws for the nonlinear Saint Venant–Kirchhoff material, and the classical Galerkin finite element method is used to discretize the governing equations in a Lagrangian frame. A special attention is given to construct an algorithm with exact total fluid volume conservation while obeying both the global and the local discrete geometric conservation law. The resulting large‐scale algebraic nonlinear equations are multiplied with an upper triangular right preconditioner that results in a scaled discrete Laplacian instead of a zero block in the original system. Then, a one‐level restricted additive Schwarz preconditioner with a block‐incomplete factorization within each partitioned sub‐domains is utilized for the modified system. The accuracy and performance of the proposed algorithm are verified for the several benchmark problems including a pressure pulse in a flexible circular tube, a flag interacting with an incompressible viscous flow, and so on. John Wiley & Sons, Ltd.
Equivalent plastic strain gradient crystal plasticity – Enhanced power law subroutine
Authors: Wulfinghoff Stephan , Böhlke Thomas 
Published: August 2015

AbstractA gradient crystal plasticity theory is presented including a defect energy based on the gradient of an equivalent plastic strain measure. Preserving the single crystal slip kinematics, the gradient hardening contribution models dislocation long range interactions adding a back‐stress term to the flow rule, similar to other gradient crystal plasticity theories. Owing to a reduced number of four nodal degrees of freedom the finite element implementation can handle systems consisting of an increased number of grains (compared to other theories) without elaborate or costly computer systems. Emphasis is put on the enhancement of the power law material subroutine. The associated implicit Euler scheme is optimized based on an improved starting value for the Newton scheme. Three‐dimensional simulations illustrate that the proposed algorithm facilitates significantly larger time steps compared to the standard Newton scheme. (© 2013 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)
Crystal plasticity based modeling of time and scale dependent behavior of thin films
Authors: Ertürk İ. , Gao K. , Bielen J. , van Dommelen J.A.W. , Geers M.G.D. 
Published: August 2015

AbstractThe micro and sub‐micro scale dimensions of the components of modern high‐tech products pose challenging engineering problems that require advanced tools to tackle them. An example hereof is time dependent strain recovery, here referred to as anelasticity, which is observed in metallic thin film components of RF‐MEMS switches. Moreover, it is now well known that the properties of a thin film material strongly depend on its geometrical dimensions through so‐called size effects. A strain gradient crystal plasticity formulation (SGCP) was recently proposed [1–4], involving a back stress in terms of strain gradients capturing the lattice curvature effect. In the present work, the SGCP model is used in a realistic simulation of electrostatic bending of a free standing thin film beam made of either a pure fcc metal or a particle strengthened Al‐Cu alloy. The model capabilities to describe the anelastic and plastic behavior of metallic thin films in comparison with experimentally available data are thereby assessed. Simulation results show that the SGCP model is able to predict a macroscopic strain recovery over time following the load removal. The amount of the anelastic relaxation and the accompanying relaxation times result from the rate dependent modeling approach, the basis of which is phenomenological only. The SGCP model is not fully capable of describing the permanent deformations in an alloy thin beam as observed in electrostatic experiments. Hence, to incorporate realistic time constants and the influence of the microstructure into the mechanical behavior of the thin film material, an improved constitutive law for crystallographic slip is necessary within the SGCP formulation. (© 2013 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)
Liposomal treatment of xerostomia, odor, and taste abnormalities in patients with head and neck cancer
Authors: Heiser Clemens , Hofauer Benedikt , Scherer Elias , Schukraft Johannes , Knopf Andreas 
Published: August 2015

AbstractBackgroundSmell and taste disorders, sicca symptoms, can be detected in patients with head and neck cancer. The purpose of this study was to assess the utility of local liposomal application in the treatment of patients with head and neck cancers.MethodsNinety‐eight patients with head and neck cancer were included in this study. The groups were defined as: group 1 = only surgery; group 2 = surgery + adjuvant radiochemotherapy; and group 3 = primarily radiochemotherapy. All patients had finished cancer treatment and received liposomal sprays for the nose and mouth for 2 months (LipoNasal, LipoSaliva; Optima Pharmaceutical GmbH, Germany) and suffered from taste and smell disorders. We performed tests with “Sniffin' Sticks,” “Taste Strips,” and a xerostomia questionnaire before and after treatment.ResultsAfter application of liposomes, patients demonstrated a statistically significant increase in smell and taste, and reduced xerostomia.ConclusionOur results demonstrate that using nonpharmaceutical liposomal sprays improve smell, taste, and symptoms of xerostomia in patients with head and neck cancer. © 2015 Wiley Periodicals, Inc. Head Neck 38: E1232–E1237, 2016
Accuracy of 18FDG PET‐CT for treatment evaluation 3 months after completion of chemoradiotherapy for head and neck squamous cell carcinoma: 2‐year minimum follow‐up
Authors: Sagardoy Thomas , Fernandez Philippe , Ghafouri Abdullah , Digue Laurence , Haaser Thibaud , de Clermont‐Galleran Henri , Castetbon Vincent , de Monès Erwan 
Published: August 2015

AbstractBackgroundThe purpose of this study was to assess the accuracy of 18F‐fluorodeoxyglucose positron emission tomography (18FDG PET)‐CT in detecting residual or recurrent disease after nonsurgical treatment for head and neck squamous cell carcinoma (HNSCC).MethodsWe conducted a retrospective analysis of patients with oral cavity, oropharynx, larynx, hypopharynx, or cervical lymph node location of SCC treated with chemoradiotherapy. Twelve weeks posttreatment, 18FDG PET‐CT results were compared to histology if residual disease was suspected. Patients with complete response received a minimum of 24‐month follow‐up.ResultsForty‐seven patients were included with 40 months of median follow‐up: 46 with a squamous cell carcinoma (SCC) at the primary site and 43 in the neck. Sensitivity, specificity, positive predictive value (PPV), and negative predictive value (NPV) were 86.7%, 90%, 76.5%, and 93.1%, respectively, at the primary site and 100%, 97.2%, 87.5%, 100%, respectively, in the neck.Conclusion18FDG PET‐CT seems effective in detecting residual disease and in predicting recurrent disease within the first 2 years of follow‐up after nonsurgical treatment. © 2015 Wiley Periodicals, Inc. Head Neck 38: E1271–E1276, 2016
Surgeon performed ultrasound‐guided fine‐needle aspirates of the thyroid: 1067 biopsies and learning curve in a teaching center
Authors: Fernandes Vinay T. , Magarey Matthew J. R. , Kamdar Dev P. , Freeman Jeremy L. 
Published: August 2015

AbstractBackgroundSurgeon performed ultrasound‐guided fine‐needle aspirates (UG‐FNAs) reduce delay in diagnosis and allow for surgeon surveillance. We present the first report on a learning curve and impact of head and neck surgical trainees on adequacy rates.MethodsThyroid UG‐FNA biopsies from 2009 to 2013 were reviewed retrospectively. Specimen adequacy, cytologic diagnosis, and surgical pathology were used to calculate adequacy and accuracy.ResultsOne thousand sixty‐seven biopsies were examined in 723 individuals. The adequacy rate from adoption into practice improved from 71% to 78% to 85% over 300 cases. When UG‐FNA was subsequently taught to trainees, adequacy rates varied among trainees (p < .037), and there were higher nondiagnostic rates earlier in training (p = .04). Adequacy was not related to size or palpability, but cystic lesions yielded more inadequate specimens (p < .001).ConclusionSurgeon performed UG‐FNA biopsy can be performed adequately in an outpatient setting. Adequacy rates reach acceptable levels after 300 cases, whereas trainee involvement impacts adequacy rates. © 2015 Wiley Periodicals, Inc. Head Neck 38: E1281–E1284, 2016
Obituary: Cornelius H. Vanderwolf
Authors: Buzsáki György , Bland Brian H. 
Published: August 2015

ABSTRACTC.H. Vanderwolf described motor correlates of hippocampal theta oscillations and uncovered two broad classes: atropine‐sensitive and atropine‐resistant rhythm with likely different behavioral and cognitive significance. © 2015 Wiley Periodicals, Inc.