bluuebunny/crossref_metadata_2025_split huggingface dataset:
The Effect of Solidification Dynamics on the Formation of the Skin in Die Cast Mg–Al and Mg–RE Alloys
Authors: Yang Kun Vanna , Easton Mark A. , Cáceres Carlos H. 
Published: November 2012

AbstractThe grain microstructures and hardness of the surface layers of a Mg–RE alloy (3.44 mass % La) and two Mg–Al alloys, (8.77 and 11.6 mass % Al), are compared. All three alloys exhibit a harder surface layer, or skin, with fine primary α (Mg) grains, and a softer core with a larger grain size due to the prevalence of externally solidified grains (ESGs), but the skin of the RE alloy is more continuous and uniform due to the relative absence of ESGs. The distribution of ESGs can be related to the rheology of the liquid–solid mixtures inside the die: the solid fraction in the RE alloy, for given drop in temperature, is much larger than for the Mg–Al alloys. Being more viscous, the liquid in the RE alloy prevents the migration of ESGs towards the surface, hence the more uniform and tightly packed grain microstructure and better defined skin.
Three‐Dimensional Concentration Mapping of Organic Blends
Authors: Roehling John D. , Batenburg K. Joost , Swain F. Benjamin , Moulé Adam J. , Arslan Ilke 
Published: November 2012

AbstractThe three‐dimensional morphology of mixed organic layers are quantitatively measured using high‐angle annular dark‐field scanning transmission electron microscopy (HAADF‐STEM) with electron tomography for the first time. The mixed organic layers used for organic photovoltaic applications have not been previously imaged using STEM tomography as there is insufficient contrast between donor and acceptor components. Contrast is generated by substituting fullerenes with endohedral fullerenes that contain a Lu3N cluster within the fullerene cage. The high contrast and signal‐to‐noise ratio, in combination with use of the discrete algebraic reconstruction technique (DART), allows generation of the most detailed and accurate three‐dimensional map of BHJ morphology to date. From the STEM‐tomography reconstructions it is determined that three distinct material phases are present within the BHJs. By observing changes to morphology and mixing ratio during thermal and solvent annealing, the effects of mutual solubility and fullerene crystallization on morphology and long term stability are determined. This material/technique combination shows itself as a powerful tool for examining morphology in detail and allows for observation of nanoscopic changes in local concentration.
Increased risk of breast cancer in women with NF1
Authors: Madanikia Sara Aileen , Bergner Amanda , Ye Xiaobu , Blakeley Jaishri O'Neill 
Published: November 2012

AbstractNeurofibromatosis type 1 (NF1) is a common autosomal dominant disorder associated with increased risk for neoplasms. Two studies in the United Kingdom have indicated that women with NF1 (particularly women under 50) may also be at increased risk of breast cancer. No such study has been done to date in the United States. Chart review for breast cancer diagnoses was undertaken for 126 women with NF1 followed at Johns Hopkins who were 20 years of age or older. Four of 126 women who met eligibility criteria were diagnosed with breast cancer (3.2% over 15 years). The unadjusted standardized incidence ratio (SIR) for breast cancer in the NF1 population between the ages of 20 and 49 was 2.68 (P = 0.076, 95% CI 0.68–7.29) based on incidence rates of breast cancer in the general population taken from the Surveillance Epidemiology and End Results (SEER) database. The unadjusted SIR for women with NF1 ≥50 was 0.81 (P = 0.84, 95% CI 0.041–4.01). When adjusted for race, the rate of NF1 in the general population and time of diagnosis, the SIR was 4.41 (P = 0.0049, 95% CI 1.12–12.00) for women <50 versus 0.94 (P = 0.95, 95% CI 0.047–4.65) for women ≥50. The trend of a higher‐than‐expected number of breast cancer cases in women <50 with NF1 agrees with the prior studies from the literature. Cumulatively, the data suggests an increased risk of breast cancer for women with NF1 < 50 years old, implying a need for closer surveillance and the establishment of screening guidelines for this patient population. © 2012 Wiley Periodicals, Inc.
N‐Methylation of Peptides and Proteins: An Important Element for Modulating Biological Functions
Authors: Chatterjee Jayanta , Rechenmacher Florian , Kessler Horst 
Published: November 2012

AbstractN‐Methylation is one of the simplest chemical modifications often occurring in peptides and proteins of prokaryotes and higher eukaryotes. Over years of evolution, nature has employed N‐methylation of peptides as an ingenious technique to modulate biological function, often as a mode of survival through the production of antibiotics. This small structural change can not only mobilize large protein complexes (as in the histone methylation), but also inhibits the action of enzymes by selective recognition of protein–protein interaction surfaces. In recent years through the advancement in synthetic approaches, the potential of N‐methylation has begun to be revealed, not only in modulating biological activity and selectivity as well as pharmacokinetic properties of peptides, but also in delivering novel drugs. Herein, we summarize the current knowledge of the versatility of N‐methylation in modulating biological, structural, and pharmacokinetic properties of peptides.
Production of 3D scaffolds applied to tissue engineering using chitosan swelling as a porogenic agent
Authors: Mendonça Roberta Helena , de Oliveira Meiga Taíla , da Costa Marysilvia Ferreira , da Silva Moreira Thiré Rossana Mara 
Published: November 2012

AbstractThe preparation of 3D scaffolds using poly(3‐hydroxybutyrate) (PHB) and chitosan (CTS) has been proposed because of the favorable interactions of these materials with mammalian cells in particular osteoblasts (HOB). In this work, a new method of producing porous 3D scaffolds based on the swelling of a dense matrix of PHB and CTS was developed. Scanning electron microscopy images showed the formation of an interconnected porous CTS structure inside a PHB structure. The pore formation was attributed to the swelling of CTS. The scaffolds presented 70% porosity, heterogeneous pore‐size distribution, and a compressive modulus equal to (13.07 ± 0.014) MPa, which is close to that of cancellous bone. In vitro cytotoxicity assays indicate that the scaffold was not cytotoxic. Its morphology, chemical, and physical properties indicate that the scaffold produced by this new methodology has potential applications in bone‐tissue engineering, with drug‐delivery capabilities. © 2012 Wiley Periodicals, Inc. J. Appl. Polym. Sci., 2013
Thermorheological behavior analysis of mLLDPE and mVLDPE: Correlation with branching structure
Authors: Dordinejad A. K. , Jafari S. H. , Khonakdar H. A. , Wagenknecht U. , Heinrich G. 
Published: November 2012

AbstractIn this article, the correlation between the thermorheological behavior and the molecular structure of two grades of metallocene polyethylene, namely linear low density and very low density polyethylene, is studied. The investigated polymers possess the same molecular weight and polydispersity index, but different levels of short branches. Increasing the number of short branches results in enhanced activation energy and delayed relaxation times of the polymers. Four methods including the time–temperature superposition (TTS), van Gurp‐Palmen and activation energy (Ea) as a function of the phase angle, Ea(δ), and the storage modulus, Ea(G′) are employed to study the thermorheological behavior of the samples. The results indicated that the thermorheologically simple behavior is dominant in the specimens. Both the Ea(δ) and Ea(G′) showed independency toward phase angle and the storage modulus. Moreover, the activation energy values obtained from the TTS principle and the Ea(δ) and Ea(G′) diagrams were in good agreement. The zero‐shear rate viscosity of the samples also followed the equation of the linear polyethylene. Regarding the simple thermorheological behavior and the agreement of the zero shear rate viscosity with the relation of the linear polyethylene, one can conclude that long branches do not exist in the investigated metallocene polyethylenes of this article. © 2012 Wiley Periodicals, Inc. J. Appl. Polym. Sci., 2013
Nanocomposite piezoelectric films of P(VDF‐TrFE)/LiNbO3
Authors: Nguyen Van Son , Badie Laurent , Lamouroux Emmanuel , Vincent Brice , Santos Fabrice Domingues Dos , Aufray Maëlen , Fort Yves , Rouxel Didier 
Published: November 2012

AbstractPiezoelectric films were prepared by incorporation of lithium niobate (LiNbO3) nanoparticles into copolymer of vinylidene difluoride and trifluoroethylene. Nanoparticles of LiNbO3 with ferroelectric phase were successfully synthesized and dispersed homogenously by ultrasonication in the copolymer matrix without any surfactant or surface functionalization. The nanocomposites were fully characterized by electronic microscopy, X‐ray diffraction, differential scanning calorimetry, dynamical mechanical analysis, and piezometer. Surprisingly, the copolymer matrix crystallinity and morphology were not affected by the incorporation of nanoparticles. Therefore the nanocomposites remained good mechanicals properties and high ferroelectricity coupled to nonlinear optical activity thanks to the noncentro symmetric space group of lithium niobate. This could be a novel approach to develop new multifunctional materials. © 2012 Wiley Periodicals, Inc. J. Appl. Polym. Sci., 2013
Natural weather, soil burial and sea water ageing of low‐density polyethylene: Effect of starch/linear low‐density polyethylene masterbatch
Authors: Elanmugilan M. , Sreekumar P. A. , Singha N. K. , Al‐Harthi Mamdouh A. , De S. K. 
Published: November 2012

AbstractDegradation of the blends of low‐density polyethylene (LDPE) with a starch‐based additive namely, polystarch N was studied under various environmental conditions such as natural weather, soil and sea water in Saudi Arabia. Stress–strain properties and thermal behavior were investigated for the LDPE and LDPE/polystarch N blend having 40% (w/w) of polystarch N. Environmental ageing resulted in the reduction of percentage of elongation and crystallinity for the blend. Rheological studies and scanning electron microscope photomicrographs of the polymer samples retrieved after ageing showed that addition of polystarch N enhanced the degradation of LDPE. This is ascribed to high extent of chain scission and leaching out of starch present in polystarch N, which was corroborated by the results of morphology and Fourier transform infrared spectroscopy analyses. In the case of underground soil ageing, microbes present in the soil consume the starch in the blend, thus accelerating the degradation process. © 2012 Wiley Periodicals, Inc. J. Appl. Polym. Sci., 2013
Morphogenesis of the Manubrium of Sternum in Human Embryos: A New Concept
Authors: Rodríguez‐Vázquez José Francisco , Verdugo‐López Samuel , Garrido Jose Manuel , Murakami Gen , Kim Ji Hyun 
Published: November 2012

AbstractTo revisit many theories on fetal development of the manubrium of the sternum, we examined 25 mid‐term fetuses at 6–9 weeks of gestation. The initial developmental stage of the manubrium was characterized by a distinct interclavicular mesenchyme that was continuous with the developing clavicles. Because parts of the clavicle in which endochondral ossification occurs originate from the neural crest, the interclavicular mesenchyme seems to be of the same origin. The sternal bands, possibly of the lateral plate origin, were restricted at the anterior ends of the ribs in the paired thoracic walls. The interclavicular mesenchyme extended caudally and laterally to reach the anterior ends of the first ribs, and thus the interclavicular mesenchyme expanded into the intercostoclavicular mesenchyme. Then, the primitive manubrium was delimited by the sternoclavicular joint and its related ligaments, all of which developed from the interclavicular and intercostoclavicular mesenchymes. Although the first ribs were attached to the intercostoclavicular mesenchyme, the former was vimentin‐negative in contrast to the latter, positive mesenchyme. Soon afterwards, the small upper end of the sternal bands was integrated into the intercostoclavicular mesenchyme to form the primitive manubrium. The infrahyoid muscles and their supplying nerves maintained a close topographical relation to the interclavicular or intercostoclavicular mesenchyme, whereas the pectoralis major muscle kept attachments to the sternal bands. Consequently, the manubrium of sternum appeared to develop in a complex way at a junction area between derivatives of the neural crest, lateral plate, and somite. Anat Rec, 2013. © 2012 Wiley Periodicals, Inc.
Exploring the Interaction between Graphene Derivatives and Metal Ions as a Key Step towards Graphene–Inorganic Nanohybrids
Authors: Wang Bin , Song Qi , Luo Bin , Li Xianglong , Liang Minghui , Feng Xinliang , Wagner Manfred , Müllen Klaus , Zhi Linjie 
Published: November 2012

AbstractThe assembly of graphene derivatives and inorganic nanostructures opens up an exciting new field in the functionalization of nanomaterials. However, a better understanding of the interaction between graphene derivatives and inorganic precursors remains a challenge. This work provides an efficient strategy for exploring this interaction by first modifying graphene oxide with aniline, glycine, and glycyl glycine, respectively, and thus engineering the chemical microenvironments on graphene sheets for anchoring metal ions. After that, the affinities of graphene derivatives to various metal ions can be investigated with the help of a conventional electrochemical method. The method highlights the importance of graphene chemistry in hybrid preparation and provides design principles for chemical modifiers used in the construction of multifunctional carbon–inorganic nanostructures.
Chlorophyll Catabolites in Senescent Leaves of the Lime Tree (Tilia cordata)
Authors: Scherl Mathias , Müller Thomas , Kräutler Bernhard 
Published: November 2012

AbstractIn cold extracts of senescent leaves of the Lime tree (Tilia cordata), two colorless nonfluorescent chlorophyll catabolites (NCCs) were identified, named Tc‐NCC‐1 and Tc‐NCC‐2, as well as a polar yellow chlorophyll catabolite (YCC), named Tc‐YCC. The constitution of the two NCCs was determined by spectroscopic means. In addition, a tentative structure was derived for Tc‐YCC. The three chlorophyll degradation products exhibited tetrapyrrolic structures, as are typical of NCCs or YCCs, and turned out to be rather polar, due to a glucopyranosyl group at their 82‐position. At their 3‐positions, the more polar Tc‐NCC‐1 carried a 1,2‐dihydroxyethyl group and the less polar Tc‐NCC‐2 a vinyl group. Tc‐YCC was identified as the product of an oxidation of Tc‐NCC‐1.
Identification of the Polyhydroxybutyrate Granules in Mammalian Cultured Cells
Authors: Elustondo Pia , Zakharian Eleonora , Pavlov Evgeny 
Published: November 2012

AbstractPoly‐3‐hydroxybutyrate (PHB) is a biological polyester present in bacteria and eukaryotic cells. Long‐chain (or storage) sPHB (up to 100,000 residues) is typically present in PHB‐accumulating bacteria and localized in specialized granules known as carbonosomes. In these organisms, sPHB plays a major role as carbon and energy storage. On the other hand, short‐chain (or complexed) cPHB (10–100 residues) is present in eukaryotic organisms, including mammals as well as in many bacteria. Previous studies indicated that cPHB is localized in various subcellular compartments of the eukaryotic organisms. Here, we used fluorescent microscopy to directly investigate the localization of PHB in mammalian cells. PHB was visualized in cultured U87 cells using fluorescent probe BODIPY 493/503. Specificity of PHB staining was confirmed by markedly decreased fluorescence of samples treated with PHB‐specific depolymerase (PhaZ7). We found that PHB is associated with granules, and that these PHB‐enriched granules do not co‐localized with mitochondria, lysosomes, or endoplasmic reticulum. These results suggest that, in mammalian cells, PHB can accumulate in the cytoplasm in granules similar to ‘energy storage’ carbonosomes found in PHB‐accumulating bacteria.
New Tripeptide‐Based Macrocyclic Calpain Inhibitors Formed by N‐Alkylation of Histidine
Authors: Chen Hongyuan , Jiao Wanting , Jones Matthew A. , Coxon James M. , Morton James D. , Bickerstaffe Roy , Pehere Ashok D. , Zvarec Ondrej , Abell Andrew D. 
Published: November 2012

AbstractTwo new series of 15‐membered macrocyclic peptidomimetics, in which the P1 and P3 residues of the peptide backbone are linked by a bridge containing a 1,4‐disubstituted 1H‐imidazole, are reported. The structure with an aldehyde at the C‐terminus and the imidazole at P3, i.e., 4c, shows significant inhibitory activity against calpain 2, with an IC50 value of 238 nM. The macrocyclic aldehyde with the imidazole at the alternative P1 position, i.e., 5c, is significantly less active. The relative activities are linked to the ability of the component macrocycles to mimic a β‐strand geometry that is known to favor active‐site binding. This ability is defined by conformational searches and docking studies with calpain.
Synthesis of Highly Functionalized Fluorinated Cispentacin Derivatives
Authors: Nonn Melinda , Kiss Loránd , Hänninen Mikko M. , Sillanpää Reijo , Fülöp Ferenc 
Published: November 2012

AbstractFluorinated highly functionalized cispentacin derivatives were synthetised starting from an unsaturated bicyclic β‐lactam through CC bond functionalization via the dipolar cycloaddition of a nitrile oxide, isoxazoline opening, and fluorination by OH/F exchange.
Hydrothermal Synthesis of Pencil‐like SAPO‐5 and Observation of Its Reversed Crystal‐Growth Process
Authors: Yang Qing , Li Ming , Zeng Changfeng , Zhang Lixiong 
Published: November 2012

AbstractSAPO‐5 with a novel hexagonal pencil‐like morphology was hydrothermally synthesized from hydrogels that contain triethylamine and high concentrations of acetic acid at 180 °C for 48 h. The effect of the acetic acid concentration was examined and indicated that usage of a high concentration of acetic acid is crucial to the synthesis of SAPO‐5 with a pencil‐like morphology. The time‐dependent growth process of novel SAPO‐5 was observed by scanning electron microscopy with the aid of acid treatment to remove the amorphous materials for clearer observation. The samples were also characterized by X‐ray diffraction and Fourier‐transform infrared spectroscopy. The results show that the crystal growth at the early stage follows the reversed crystal‐growth route. First, the crystallization occurs on the surface of the aggregated amorphous ellipsoidal particles to form a hexagonal prism crystal shell with the encapsulation of amorphous materials. Then, the amorphous materials wrapped inside start to grow to a hexagonal prism inside the hollow larger hexagonal prism shell. Finally, the interior hexagonal prism continues to grow to the two ends with its length beyond that of the larger one by means of the Ostwald ripening process, thus forming the pencil‐like crystal.
ChemInform Abstract: Intermetallic Solid Solution Fe1‐xCoxGa3: Synthesis, Structure, NQR Study and Electronic Band Structure Calculations.
Authors: Shevelkov A. V. , et al. et al. 
Published: November 2012

AbstractThe title solid solutions with 0 ≤ x ≤ 1 are synthesized from the elements using excess Ga (1123 K, 55 h).
ChemInform Abstract: Synthesis, Structure, Physical Properties, and Electronic Structure of KGaSe2.
Authors: Feng Kai , Mei Dajiang , Bai Lei , Lin Zheshuai , Yao Jiyong , Wu Yicheng 
Published: November 2012

AbstractHigh quality single crystals of the title compound are synthesized by solid state reaction of K2Se and Ga2Se3 (sealed silica tube, 800 °C, 72 h) and characterized by single crystal XRD, IR spectroscopy, diffuse reflectance spectroscopy, and DFT band structure calculations.
ChemInform Abstract: Structural Distortions in Sr3‐xAxMO4F (A: Ca, Ba; M: Al, Ga, In) anti‐Perovskites and Corresponding Changes in Photoluminescence.
Authors: Sullivan Eirin , Avdeev Maxim , Vogt Thomas 
Published: November 2012

AbstractSr2.975Ce0.025AlO4F, Sr2.95Ce0.025Na0.025AlO4F, and Sr2.25Ba0.6Eu0.1M0.95 In0.05O4‐αF1‐δ (M: Al, Ga) are characterized by neutron powder diffraction.
ChemInform Abstract: Full Differentiation and Assignment of Boron Species in the Electrolytes Li2B6O9F2 and Li2B3O4F3 by Solid‐State 11B NMR Spectroscopy.
Authors: Braeuniger Thomas , Pilz Thomas , Chandran C. Vinod , Jansen Martin 
Published: November 2012

AbstractThe title compounds, which possess considerable ion conductivity at higher temperatures, are characterized by solid state 11B MAS NMR spectroscopy.
ChemInform Abstract: Robust Acenaphthoimidazolylidene Palladium Complexes: Highly Efficient Catalysts for Suzuki—Miyaura Couplings with Sterically Hindered Substrates.
Authors: Tu Tao , Sun Zheming , Fang Weiwei , Xu Mizhi , Zhou Yunfei 
Published: November 2012

AbstractAt low catalyst loading, aryl bromides or aryl chlorides undergo the title coupling reaction to give di‐, tri‐ and tetra‐ortho‐substituted biaryls in excellent yields, including functionalized biaryls.
ChemInform Abstract: Highly Enantioselective Electrophilic α‐Bromination of Enecarbamates: Chiral Phosphoric Acid and Calcium Phosphate Salt Catalysts.
Authors: Alix Aurelien , Lalli Claudia , Retailleau Pascal , Masson Geraldine 
Published: November 2012

AbstractThe stereochemical reversal observed by changing the catalyst from chiral phosphoric acid to its calcium salt, is explained by different transition state models.
ChemInform Abstract: Selective “One‐Pot” Synthesis of Functionalized Cyclopentenones.
Authors: Varea Teresa , Alcalde Ana , Lopez de Dicastillo Carolina , Ramirez de Arellano Carmen , Cossio Fernando P. , Asensio Gregorio 
Published: November 2012

AbstractReaction of squaric acid derivatives with vinyl magnesium bromide followed by treatment with trifluoroethanol allows a new and stereoselective access to functionalized cyclopentenones of type (III)/ (V).
ChemInform Abstract: A Practical and General Diels—Alder Reaction of Pentafulvenes with Arynes.
Authors: Bhojgude Sachin Suresh , Kaicharla Trinadh , Bhunia Anup , Biju Akkattu T. 
Published: November 2012

AbstractUsing an optimized amount of CsF for the generation of the arynes from silylaryl triflates, a range of benzo‐fused norbornadiene derivatives is formed by cycloaddition with 6‐ or 6,6‐substituted pentafulvenes.
ChemInform Abstract: Synthesis of Alcohols via a Rhodium‐Catalyzed Hydroformylation—Reduction Sequence Using Tertiary Bidentate Amine Ligands.
Authors: Cheung Lawrence L. W. , Vasapollo Giuseppe , Alper Howard 
Published: November 2012

AbstractAromatic styrenes and related compounds give the desired alcohols with excellent chemoselectivity employing optimized conditions (solvent, reaction temperature, gas pressure, ligand).
ChemInform Abstract: Unusual Michael Reaction of 3‐(4‐Chlorophenyl)‐1‐phenylprop‐2‐en‐1‐one with 3‐Amino‐N‐phenyl‐3‐thioxopropanamide.
Authors: Dyachenko V. D. , Krasnikov D. A. 
Published: November 2012

AbstractNaOH‐mediated reaction of chalcone (I) with thioxopropanamide (II) in EtOH does not yield the expected pyridinethione (V), but a Michael type adduct (III).
ChemInform Abstract: Palladium‐Catalyzed Cyanide Metathesis: Utilization of Benzyl Cyanide as an Operator‐Benign Reagent for Aryl Halide Cyanations.
Authors: Wen Qiaodong , Jin Jisong , Hu Binbin , Lu Ping , Wang Yanguang 
Published: November 2012

AbstractBenzyl cyanide (II) is a safe and effective cyanation reagent for palladium‐catalyzed cyanation of haloarenes, affording the corresponding aryl nitriles in moderate to good yields.
ChemInform Abstract: Novel Synthetic Methodologies. Part 11. A Facile and Efficient Bi(III) Catalyzed Synthesis of 1,1‐Dihydroperoxides and 1,2,4,5‐Tetraoxanes.
Authors: Sashidhara Koneni V. , Avula Srinivasa Rao , Singh L. Ravithej , Palnati Gopala Reddy 
Published: November 2012

AbstractA highly efficient synthesis of 1,1‐dihydroperoxides is achieved by Bi(III)‐catalyzed oxidation of aldehydes or ketones with hydrogen peroxide.