bluuebunny/crossref_metadata_2025_split huggingface dataset:
Prognostic value of quantitative fluorodeoxyglucose measurements in newly diagnosed metastatic breast cancer
Authors: Ulaner Gary A. , Eaton Anne , Morris Patrick G. , Lilienstein Joshua , Jhaveri Komal , Patil Sujata , Fazio Maurizio , Larson Steven , Hudis Clifford A. , Jochelson Maxine S. 
Published: September 2013

AbstractThe aim of this study was to determine the prognostic value of quantitative fluorodeoxyglucose (FDG) measurements (maximum standardized uptake value [SUVmax], metabolic tumor volume [MTV], and total lesion glycolysis [TLG]) in patients with newly diagnosed metastatic breast cancer (MBC). An IRB‐approved retrospective review was performed of patients who underwent FDG positron emission tomography (PET)/computed tomography (CT) from 1/02 to 12/08 within 60 days of diagnosis MBC. Patients with FDG‐avid lesions without receiving chemotherapy in the prior 30 days were included. Target lesions in bone, lymph node (LN), liver, and lung were analyzed for SUVmax, MTV, and TLG. Medical records were reviewed for patient characteristics and overall survival (OS). Cox regression was used to test associations between quantitative FDG measurements and OS. A total of 253 patients were identified with disease in bone (n = 150), LN (n = 162), liver (n = 48), and lung (n = 66) at the time of metastatic diagnosis. Higher SUVmax tertile was associated with worse OS in bone metastases (highest vs. lowest tertile hazard ratio [HR] = 3.1, P < 0.01), but not in LN, liver or lung (all P > 0.1). Higher MTV tertile was associated with worse OS in LN (HR = 2.4, P < 0.01) and liver (HR = 3.0, P = 0.02) metastases, but not in bone (P = 0.22) or lung (P = 0.14). Higher TLG tertile was associated with worse OS in bone (HR = 2.2, P = 0.02), LN (HR = 2.3, P < 0.01), and liver (HR = 4.9, P < 0.01) metastases, but not in lung (P = 0.19). We conclude measures of FDG avidity are prognostic biomarkers in newly diagnosed MBC. SUVmax and TLG were both predictors of survival in breast cancer patients with bone metastases. TLG may be a more informative biomarker of OS than SUVmax for patients with LN and liver metastases.
Functionalisation and surface modification of electrospun polylactic acid scaffold for tissue engineering
Authors: Hoveizi Elham , Nabiuni Mohammad , Parivar Kazem , Rajabi‐Zeleti Sareh , Tavakol Shima 
Published: September 2013

AbstractRepair or replacement of damaged tissues using tissue engineering technology is considered to be a fine solution for enhanced treatment of different diseases such as skin diseases. Although the nanofibers made of synthetic degradable polymers, such as polylactic acid (PLA), have been widely used in the medical field, they do not favour cellular adhesion and proliferation. To enhance cell adherence on scaffold and improve biocompatibility, the surface of PLA scaffold was modified by gelatin in our experiments. For electrospinning, PLA and gelatin were dissolved in hexafluoroisopropanol (HFIP) solvent at varying compositions (PLA:gelatin at 3:7 and 7:3). The properties of the blending nanofiber scaffold were investigated by Fourier transform infrared (FT‐IR) spectroscopy and scanning electron microscopy (SEM). Modified PLA/gelatin 7/3 scaffold is more suitable for fibroblasts attachment and viability than the PLA or gelatin nanofiber alone. Thus fibroblast cultured on PLA/gelatin scaffold could be an alternative way to improve skin wound healing.
Chemical Inhomogeneity, Short‐Range Order, and Magnetism in the LiNiO2‐NiO Solid Solution
Authors: Barton Phillip T. , Premchand Y. Daniel , Chater Philip A. , Seshadri Ram , Rosseinsky Matthew J. 
Published: September 2013

AbstractNiO:Li is an early exemplar for which hole‐doping of a correlated insulator gives rise to rich and varied magnetic behavior. It is also an important system from the viewpoint of p‐type transparent conducting oxides, and is representative of a large class of materials that have been used in lithium ion batteries, since the end‐member compound, LiNiO2, belongs to the class of layered cathode materials. Despite the deceptive structural and compositional simplicity of this system, a complete understanding of its complex magnetic properties has remained elusive. Here a comprehensive investigation of the solid solution LixNi2−xO2, examining samples of precise stoichiometry using a combination of high‐resolution synchrotron X‐ray powder diffraction and SQUID magnetometry, is provided. The focus is on the interesting region between 0.40<x<1.00 in which the magnetic ordering temperature changes drastically with composition. The magnetism evolves from strong G‐type antiferromagnetism of x=0.40 with TN=327 K to robust uncompensated magnetic order at TN=240 K when x is close to 0.7, and to glassy A‐type antiferromagnetism of x=1.00 at TN=9 K. This study demonstrates this magnetic behavior is linked to the Li–Ni chemical order that develops from short‐ to long‐range. The interfaces between ordered domains give rise to magnetic exchange bias, which manifests as a shift in the magnetization‐field loop for samples with nanoscale coherence lengths (0.54<x<0.66).
An Amino‐Acid‐Based Self‐Healing Hydrogel: Modulation of the Self‐Healing Properties by Incorporating Carbon‐Based Nanomaterials
Authors: Roy Subhasish , Baral Abhishek , Banerjee Arindam 
Published: September 2013

AbstractAn amino‐acid‐based (11‐(4‐(pyrene‐1‐yl)butanamido)undecanoic acid) self‐repairing hydrogel is reported. The native hydrogel, as well as hybrid hydrogels, have been thoroughly characterized by using various microscopic techniques, including transmission electron microscopy (TEM), atomic force microscopy (AFM), Raman spectroscopy, fluorescence spectroscopy, FTIR spectroscopy, X‐ray diffraction, and by using rheological experiments. The native hydrogel exhibited interesting fluorescence properties, as well as a self‐healing property. Interestingly, the self‐healing, thixotropy, and stiffness of the native hydrogel can be successfully modulated by incorporating carbon‐based nanomaterials, including graphene, pristine single‐walled carbon nanotubes (Pr‐SWCNTs), and both graphene and Pr‐SWCNTs, within the native gel system. The self‐recovery time of the gel was shortened by the inclusion of reduced graphene oxide (RGO), Pr‐SWCNTs, or both RGO and Pr‐SWCNTs. Moreover, hybrid gels that contained RGO and/or Pr‐SWCNTs exhibited interesting semiconducting behavior.
Exploring Supramolecular Self‐Assembly of Tetraarylporphyrins by Halogen Bonding: Crystal Engineering with Diversely Functionalized Six‐Coordinate Tin(L)2–Porphyrin Tectons
Authors: Titi Hatem M. , Patra Ranjan , Goldberg Israel 
Published: September 2013

AbstractThis study targets the construction of porphyrin assemblies directed by halogen bonds, by utilizing a series of purposely synthesized Sn(axial ligand)2–(5,10,15,20‐tetraarylporphyrin) [Sn(L)2‐TArP] complexes as building units. The porphyrin moiety and the axial ligands in these compounds contain different combinations of complimentary molecular recognition functions. The former bears p‐iodophenyl, p‐bromophenyl, 4′‐pyridyl, or 3′‐pyridyl substituents at the meso positions of the porphyrin ring. The latter comprises either a carboxylate or hydroxy anchor for attachment to the porphyrin‐inserted tin ion and a pyridyl‐, benzotriazole‐, or halophenyl‐type aromatic residue as the potential binding site. The various complexes were structurally analyzed by single‐crystal X‐ray diffraction, accompanied by computational modeling evaluations. Halogen‐bonding interactions between the lateral aryl substituents of one unit of the porphyrin complex and the axial ligands of neighboring moieties was successfully expressed in several of the resulting samples. Their occurrence is affected by structural (for example, specific geometry of the six‐coordinate complexes) and electronic effects (for example, charge densities and electrostatic potentials). The shortest intermolecular I⋅⋅⋅N halogen‐bonding distance of 2.991 Å was observed between iodophenyl (porphyrin) and benzotriazole (axial ligand) moieties. Manifestation of halogen bonds in these relatively bulky compounds without further activation of the halophenyl donor groups by electron‐withdrawing substituents is particularly remarkable.
Organocatalyzed Aldol Reaction between Pyridine‐2‐carbaldehydes and α‐Ketoacids: A Straightforward Route towards Indolizidines and Isotetronic Acids
Authors: Liautard Virginie , Jardel Damien , Davies Clotilde , Berlande Muriel , Buffeteau Thierry , Cavagnat Dominique , Robert Frédéric , Vincent Jean‐Marc , Landais Yannick 
Published: September 2013

AbstractEnantioselective aldol reactions between substituted pyridine carbaldehydes and α‐ketoacids were shown to provide isotetronic acids or their corresponding pyridinium salts, depending on the nature of the substituents on the pyridine ring. The pyridinium salts were generated through nucleophilic attack of the pyridine nitrogen atom onto the reactive keto functional group. Moderate‐to‐good yields of both compounds were typically obtained and high levels of enantioselectivity were observed by using benzimidazole pyrrolidine I as a catalyst. Hydrogenation of the resulting pyridinium salts led to new indolizidines with high ee values and diastereocontrol. X‐ray diffraction studies allowed the determination of the relative configuration of the products. Finally, DFT calculations were performed to rationalize the divergent pathway as a function of the pyridine substituents.
RhIII‐Catalyzed CH Activation: A Versatile Route towards Various Polycyclic Pyridinium Salts
Authors: Luo Ching‐Zong , Gandeepan Parthasarathy , Jayakumar Jayachandran , Parthasarathy Kanniyappan , Chang Yu‐Wei , Cheng Chien‐Hong 
Published: September 2013

AbstractAn efficient and convenient method for the synthesis of highly substituted polycyclic pyridinium salts from the reaction of various 2‐aryl‐pyridines and 2‐aryl‐sp2‐nitrogen‐atom‐containing heterocycles with alkynes through rhodium(III)‐catalyzed CH activation and annulation under an O2 atmosphere is described. A possible mechanism that involves the chelation‐assisted CH activation of the 2‐aryl‐pyridine substrate, insertion of the alkyne, and reductive elimination is proposed. This mechanism was supported by the isolation of a five‐membered rhodacycle (I′). In addition, kinetic isotope studies were performed to understand the intimate reaction mechanism.
Effect of Cyanide Ligands on the Electronic Structure of [FeFe] Hydrogenase Active‐Site Model Complexes with an Azadithiolate Cofactor
Authors: Erdem Özlen F. , Stein Matthias , Kaur‐Ghumaan Sandeep , Reijerse Edward J. , Ott Sascha , Lubitz Wolfgang 
Published: September 2013

AbstractA detailed characterization of a close synthetic model of the [2 Fe]H subcluster in the [FeFe] hydrogenase active site is presented. It contains the full primary coordination sphere of the CO‐inhibited oxidized state of the enzyme including the CN− ligands and the azadithiolate (adt) bridge, [((μ‐SCH2)2NR)Fe2(CO)4(CN)2]2−, R=CH2CH2SCH3. The electronic structure of the model complex in its FeIFeII state was investigated by means of density functional theory (DFT) calculations and Fourier transform infrared (FTIR) spectroscopy. By using a combination of continuous‐wave (CW) electron paramagnetic resonance (EPR) and hyperfine sublevel correlation (HYSCORE) experiments as well as DFT calculations, it is shown that, for this complex, the spin density is delocalized over both iron atoms. Interestingly, we found that the nitrogen hyperfine coupling, which represents the interaction between the unpaired electron and the nitrogen at the dithiolate bridge, is slightly larger than that in the analogous complex in which the CN− ligands are replaced with PMe3 ligands. This reveals, first, that the CN−/PMe3 ligands coordinated to the iron core are electronically coupled to the amine in the adt bridge. Second, the CN− ligands in this complex are somewhat stronger σ‐donor ligands than the PMe3 ligand, and thereby enable more spin density to be transferred from the Fe core to the adt unit, which might in turn affect the reactivity of the bridging amine.
Facile Synthesis and Enhanced Nonlinear Optical Properties of Porphyrin‐Functionalized Multi‐Walled Carbon Nanotubes
Authors: Wang Aijian , Fang Yu , Long Lingliang , Song Yinglin , Yu Wang , Zhao Wei , Cifuentes Marie P. , Humphrey Mark G. , Zhang Chi 
Published: September 2013

AbstractTwo multi‐walled carbon nanotube (MWCNT)‐based nanohybrids, MWCNT–ZnTPP and MWCNT–TPP (TPP=5‐[4‐{2‐(4‐formylphenoxy)‐ ethyloxy}phenyl]‐10,15,20‐triphenylporphyrin, ZnTPP=5‐[4‐{(4‐formylphenyl)ethynyl}phenyl]‐10,15,20‐triphenylporphinatozinc(II)), were prepared directly from pristine MWCNTs through 1,3‐dipolar cycloaddition reactions. Covalent attachment of the porphyrins to the surfaces of the MWCNTs was confirmed by Fourier transform infrared spectroscopy, ultraviolet/visible absorption, fluorescence, Raman, and X‐ray photoelectron spectroscopy, elemental analysis, transmission electron microscopy, and thermogravimetric analysis. Attachment of the porphyrin moieties to the surface of the MWCNTs significantly improves the solubility and ease of processing of these MWCNT–porphyrin composite materials. Z‐scan studies reveal that these MWCNT–porphyrin nanohybrids exhibit enhanced nonlinear optical properties under both nanosecond and picosecond laser pulses at λ=532 nm in comparison with free MWCNTs and the free porphyrin chromophores, whereas superior optical limiting performance was displayed by MWCNT–porphyrin composite materials rather than MWCNTs/ZnTPP and MWCNTs/TPP blends, which is consistent with a remarkable accumulation effect as a result of the covalent linkage between the porphyrin and the MWCNTs.
An overview on the recent advances in computational fluid dynamics simulation of spouted beds
Authors: Bao Xiaojun , Du Wei , Xu Jian 
Published: September 2013

AbstractSpouted beds are now widely applied in various physical operations and chemical reaction systems due to their unique structural and flow characteristics. Now there are growing interests to use computational fluid dynamics (CFD) to understand dense gas–solid two‐phase flows in spouted beds. Both Eulerian–Eulerian (two‐fluid model, TFM) and Eulerian–Lagrangian (discrete element method, DEM) approaches can be applied to the CFD modelling of spouted beds and spouted‐fluidised beds, and numerous verification studies have shown their reliabilities. This overview summarises the recent advances of the TFM and DEM approaches in the CFD modelling of spouted beds. The typical flow patterns of spouted beds can be well reproduced by both the TFM and the DEM approaches, and the simulated characteristic properties such as spout diameter, minimum spouting velocity and voidage profile are in good agreement with experimental data, indicating that CFD modelling based on the TFM and DEM approaches can serve as an important tool for predicting gas and solids behaviour in spouted beds. The TFM approach has been widely used in phenomenological studies that are mainly towards the understanding of the flow behaviour of the whole system. Although more computational capacity is required, the DEM approach offers a more natural way to simulate gas–solid flows, with each individual particle tracked in the simulation and can be applied readily for particle tracking, collision, mixing, circulation and mass transfer studies that are aimed at obtaining the profound particle‐scale understanding in fluid–solid multiple‐phase systems. However, each approach has its own limitations and defects. The complex nature of the TFM‐based simulation framework requires both proper descriptions of pseudo‐fluid properties like solid pressure, solid viscosity, solid friction stresses, etc. and suitable choice of drag models, and the boundary conditions also have effects on the simulation results. Moreover, the effects of these factors often interact with each other, which require even more subtle skills in conducting a simulation. In the DEM approach, the high computing source requirement limits its application of no more than several million particles. Furthermore, more insight investigation should be given to the acting mechanism of several forces on particles. One common challenge for these two approaches is to properly describe the inherent turbulence for both the solid and gas phases, especially for the spout region. Further fundamental and experimental studies on the kinematic properties of the two phases are needed to improve the accuracy of the CFD models.
Site‐Specific Carbon Deposition for Hierarchically Ordered Core/Shell‐Structured Graphitic Carbon with Remarkable Electrochemical Performance
Authors: Lv Yingying , Wu Zhangxiong , Qian Xufang , Fang Yin , Feng Dan , Xia Yongyao , Tu Bo , Zhao Dongyuan 
Published: September 2013

AbstractA fascinating core–shell‐structured graphitic carbon material composed of ordered microporous core and uniform mesoporous shell is fabricated for the first time through a site‐specific chemical vapor deposition process by using a nanozeolite@mesostructured silica composite molecular sieve as the template. The mesostructure‐directing agent cetyltrimethylammonium bromide in the shell of the template can be either burned off or carbonized so that it is successfully utilized as a pore switch to turn the shell of the template “on” or “off” to allow selective carbon deposition. The preferred carbon deposition process can be performed only in the inner microporous zeolite cores or just within the outer mesoporous shells, resulting in a zeolite‐like ordered microporous carbon or a hollow mesoporous carbon. Full carbon deposition in the template leads to the new core–shell‐structured microporous@mesoporous carbon with a nanographene‐constructed framework for fast electron transport, a microporous nanocore with large surface area for high‐capacity storage of lithium ions, a mesoporous shell with highly opened mesopores as a transport layer for lithium ions and electron channels to access inner cores. The ordered micropores are protected by the mesoporous shell, avoiding pore blockage as the formation of solid electrolyte interphase layers. Such a unique core–shell‐structured microporous@mesoporous carbon material represents a newly established lithium ion storage model, demonstrating high reversible energy storage, excellent rate capability, and long cyclic stability.
Efficient Organic Dye‐Sensitized Solar Cells: Molecular Engineering of Donor–Acceptor–Acceptor cationic dyes
Authors: Cheng Ming , Yang Xichuan , Zhao Jianghua , Chen Cheng , Tan Qin , Zhang Fuguo , Sun Licheng 
Published: September 2013

AbstractThree metal‐free donor–acceptor–acceptor sensitizers with ionized pyridine and a reference dye were synthesized, and a detailed investigation of the relationship between the dye structure and the photophysical and photoelectrochemical properties and the performance of dye‐sensitized solar cells (DSSCs) is described. The ionization of pyridine results in a red shift of the absorption spectrum in comparison to that of the reference dye. This is mainly attributable to the ionization of pyridine increasing the electron‐withdrawing ability of the total acceptor part. Incorporation of the strong electron‐withdrawing units of pyridinium and cyano acrylic acid gives rise to optimized energy levels, resulting in a large response range of wavelengths. When attached to TiO2 film, the conduction band of TiO2 is negatively shifted to a different extent depending on the dye. This is attributed to the electron recombination rate between the TiO2 film and the electrolyte being efficiently suppressed by the introduction of long alkyl chains and thiophene units. DSSCs assembled using these dyes show efficiencies as high as 8.8 %.
A novel media independent handover‐based approach for vertical handover over heterogeneous wireless networks
Authors: Omheni N. , Zarai F. , Obaidat M. S. , Hsiao K.‐F. , Kamoun L. 
Published: September 2013

SUMMARYThe key purpose for seamless mobility and service continuity between heterogeneous wireless networks is the handover. Vertical handover management is one of key challenges in such environment. To deal with some of these challenges, an IEEE 802.21 media independent handover (MIH) framework has been standardized. The main purpose of this standard is to offer a general interface for the handover by abstracting the link layer intelligence to higher layers. However, there still exist a number of limitations in MIH architecture. In this paper, a new architecture of improved MIH is presented to perform vertical handover between wireless heterogeneous networks. We focused on interworking architecture between wireless local area network and long term evolution advanced network with the use of MIH signaling to define an efficient vertical handover. A performance analysis model for the proposed MIH‐based vertical handover is derived. Analysis results show that the proposed method can be easily deployed in present multimedia service networks. Copyright © 2013 John Wiley & Sons, Ltd.
A Facile Route to Flowerlike Bi2S3 Constructed by Polycrystalline Nanoplates with Enhanced Electrochemical Properties
Authors: Jin Rencheng , Li Guihua , Liu Junshen , Yang Lixia 
Published: September 2013

AbstractIn this work, hierarchical flowerlike Bi2S3 structures constructed by polycrystalline nanoplates combined with urchinlike and wirelike Bi2S3 were synthesized by using a thioglycolic acid assisted solvothermal method. On the basis of the time‐dependent experimental results, an anion exchange process and a self‐assembly mechanism were proposed to account for the growth mechanism of the synthesized flowerlike Bi2S3. In addition, the morphology and the crystalline nature of the products can be easily tuned by changing the reaction temperature. Moreover, the electrochemical properties (electrochemical hydrogen‐storage and lithium‐intercalation performance) of the products were studied. The flowerlike Bi2S3 possesses both higher electrochemical properties and better cycle stabilities compared to urchinlike and wirelike Bi2S3.