bluuebunny/crossref_metadata_2025_split huggingface dataset:
Synthesis, characterization and luminescent properties of europium complexes with 2,4,6‐tris‐(2‐pyridyl)‐s‐triazine as highly efficient sensitizers
Authors: Kang Jie , Chen Ying‐Nan , Wang Ai‐Ling , Li Hai‐Yan , Qu Yan‐Rong , Zhang Hai‐Xia , Chu Hai‐Bin , Zhao Yong‐Liang 
Published: April 2015

AbstractUsing 2,4,6‐tris‐(2‐pyridyl)‐s‐triazine (TPTZ) as a neutral ligand, and p‐hydroxybenzoic acid, terephthalic acid and nitrate as anion ligands, five novel europium complexes have been synthesized. These complexes were characterized using elemental analysis, rare earth coordination titrations, UV/vis absorption spectroscopy and infrared spectroscopy. Luminescence spectra, luminescence lifetime and quantum efficiency were investigated and the mechanism discussed in depth. The results show that the complexes have excellent emission intensities, long emission lifetimes and high quantum efficiencies. The superior luminescent properties of the complexes may be because the triplet energy level of the ligands matches well with the lowest excitation state energy level of Eu3+. Moreover, changing the ratio of the ligands and metal ions leads to different luminescent properties. Among the complexes, Eu2(TPTZ)2(C8H4O4)(NO3)4(C2H5OH)·H2O shows the strongest luminescence intensity, longest emission lifetime and highest quantum efficiency. Copyright © 2015 John Wiley & Sons, Ltd.
Invasive Krebse in Europa
Authors: Vaeßen Susanne , Hollert Henner 
Published: April 2015

AbstractNicht heimische Krebsarten gefährden europaweit heimische Krebse, wobei dem Nordamerikanischen Signalkrebs (Pacifastacus leniusculus) durch seine Temperaturtoleranz und seine hohen Vermehrungsraten eine Schlüsselrolle zukommt. Eine dreijährige Untersuchung soll die ökologischen Auswirkungen steigender Signalkrebsdichten sowie deren verhaltensbiologischen Einfluss auf Fische dokumentieren. Es zeigte sich, dass hohe Signalkrebsdichten zu starken Einbrüchen im Makrozoobenthosvorkommen führen, was wiederum geringere Fischbestände zur Folge hat. Gleichzeitig verdrängten die Krebse Bachforellen langfristig aus Höhlen, was diese im Freiland einem höheren Jagddruck aussetzt.
Primacy of surgery for colorectal cancer
Authors: Liang J , Fazio V , Lavery I , Remzi F , Hull T , Strong S , Church J 
Published: April 2015

Abstract

Background
The optimal technique for curative resection of colonic cancer includes high ligation of the mesenteric vessels, wide excision of the colonic mesentery and prevention of tumour cell spillage. This article reports results from the authors' institution for patients in whom complete mesocolic excision was performed long before the term was coined.

Methods
Patients operated on for cure for primary adenocarcinoma of the colon between January 1994 and December 2004 were identified from a prospectively maintained, institutional review board-approved, colorectal cancer registry. Medical records and operation notes were reviewed. The primary outcomes were recurrence (local and distal) and age-adjusted 5-year survival.

Results
Some 1013 patients (560 men and 453 women) were identified, with a median age of 69 (range 21–96) years. The most common location of the cancer was the sigmoid colon (32·9 per cent), followed by the caecum (26·7 per cent) and ascending colon (17·0 per cent). Operations were performed laparoscopically in 134 patients (13·2 per cent). Median duration of hospital stay was 7 (range 1–64, mean 8·2) days. Overall morbidity and mortality rates were 13·5 and 2·2 per cent respectively; there were 20 anastomotic leaks (2·0 per cent). Some 282 patients (27·8 per cent) had stage I, 386 (38·1 per cent) stage II and 345 (34·1 per cent) stage III disease. Median lymph node yield was 28·3 (range 0–241, mean 28·3), and 12 or more nodes were examined in 88·1 per cent of patients. Adjuvant chemotherapy was administered to 277 patients (80·3 per cent) with stage III disease. Overall local and distant recurrence rates at 5 years were 5·1 and 17·1 per cent respectively. The 5-year local recurrence rate was 2·2, 5·3 and 7·7 per cent for American Joint Committee on Cancer stages I, II and III respectively. Corresponding distant recurrence rates were 4·0, 14·7 and 30·5 per cent. The 5-year overall cancer-free age-standardized survival rate was 85·3 per cent. Five-year age standardized survival rates for patients with disease stages I, II and III were 97·7, 90·8 and 69·8 per cent respectively.

Conclusion
These data define modern results of surgery for colonic cancer with conservative use of chemotherapy.
Design of experiment (DOE) for microstrip transmission line in RF and microwave undergraduate course
Authors: Aftanasar Md Shahar , Zalina Abdul Aziz , Ngah Umi Kalthum 
Published: April 2015

ABSTRACTThis paper describes the implementation of Design of Experiment (DOE) for RF and Microwave course. The objective is to demonstrate the use DOE in investigative laboratory activity for 3rd year students in RF and Microwave Course. Detailed explanation on the proposed framework, student activity, formulation, and learning process were outlined in an open‐ended cooperative laboratory activity. The scenario requires students to determine which Microstrip Transmission Line parameter significantly affects the performance of the transmission line due to a ± 5% physical variation in the parameter from its nominal value. The outcome from the study outlined the basic procedure to apply DOE as a learning process for determining factors influencing the output functional performance. © 2015 Wiley Periodicals, Inc. Comput. Appl. Eng. Educ. Comput Appl Eng Educ 23:658–666, 2015; View this article online at wileyonlinelibrary.com/journal/cae; DOI 10.1002/cae.21635
Optimal treatment scheduling of ionizing radiation and sunitinib improves the antitumor activity and allows dose reduction
Authors: Kleibeuker Esther A. , ten Hooven Matthijs A. , Castricum Kitty C. , Honeywell Richard , Griffioen Arjan W. , Verheul Henk M. , Slotman Ben J. , Thijssen Victor L. 
Published: April 2015

AbstractThe combination of radiotherapy with sunitinib is clinically hampered by rare but severe side effects and varying results with respect to clinical benefit. We studied different scheduling regimes and dose reduction in sunitinib and radiotherapy in preclinical tumor models to improve potential outcome of this combination treatment strategy. The chicken chorioallantoic membrane (CAM) was used as an angiogenesis in vivo model and as a xenograft model with human tumor cells (HT29 colorectal adenocarcinoma, OE19 esophageal adenocarcinoma). Treatment consisted of ionizing radiation (IR) and sunitinib as single therapy or in combination, using different dose‐scheduling regimes. Sunitinib potentiated the inhibitory effect of IR (4 Gy) on angiogenesis. In addition, IR (4 Gy) and sunitinib (4 days of 32.5 mg/kg per day) inhibited tumor growth. Ionizing radiation induced tumor cell apoptosis and reduced proliferation, whereas sunitinib decreased tumor angiogenesis and reduced tumor cell proliferation. When IR was applied before sunitinib, this almost completely inhibited tumor growth, whereas concurrent IR was less effective and IR after sunitinib had no additional effect on tumor growth. Moreover, optimal scheduling allowed a 50% dose reduction in sunitinib while maintaining comparable antitumor effects. This study shows that the therapeutic efficacy of combination therapy improves when proper dose‐scheduling is applied. More importantly, optimal treatment regimes permit dose reductions in the angiogenesis inhibitor, which will likely reduce the side effects of combination therapy in the clinical setting. Our study provides important leads to optimize combination treatment in the clinical setting.
Nonaqueous Synthesis of a Bismuth Vanadate Photocatalyst By Using Microwave Heating: Photooxidation versus Photosensitized Decomposition in Visible‐Light‐Driven Photocatalysis
Authors: Hofmann Max , Rainer Martin , Schulze Steffen , Hietschold Michael , Mehring Michael 
Published: April 2015

AbstractA new synthetic route to monoclinic bismuth vanadate using a concept adapted from a nonaqueous synthesis strategy for nanostructured organic–inorganic hybrid materials and metal oxides, introduced recently as twin polymerization, is reported. Microwave‐assisted synthesis starting from bismuth(III) tert‐butoxide and vanadium(V) oxytri(tert‐butoxide) in the presence of 2‐methoxybenzyl alcohol, 2,4‐dimethoxybenzyl alcohol, and 2‐(2‐thienyl)iso‐propyl alcohol gave hybrid materials, which were characterized by solid‐state 13C NMR spectroscopy, CH analysis, atomic absorption spectroscopy, and energy dispersive X‐ray spectroscopy. Subsequent pyrolysis resulted in nanoscale monoclinic bismuth vanadate that showed a high photocatalytic activity. The photocatalytic decomposition of model pollutants such as rhodamine B (RhB), methyl orange, methylene blue, and orange G under visible‐light irradiation using the as‐prepared bismuth vanadate samples was studied with a focus on the influence of the agglomeration behavior. The interplay between the photooxidation of RhB, induced by the excitation of the catalyst using visible light, and the photosensitized decomposition pathway is demonstrated by degradation experiments in solution and the solid state.
CuCo2O4 Nanowires Grown on a Ni Wire for High‐Performance, Flexible Fiber Supercapacitors
Authors: Gu Shaosong , Lou Zheng , Ma Xiangdong , Shen Guozhen 
Published: April 2015

AbstractFlexible/stretchable supercapacitors for energy harvesting and storage are being extensively studied to meet the demand of specific environments. We successfully fabricated a flexible fiber supercapacitor through a simple and rapid single‐step hydrothermal method, growing CuCo2O4 nanostructures on Ni wires to be used as fiber electrodes. Electrochemical investigations demonstrate that the electrode material can be used in a supercapacitor to give a remarkable performance. The high‐rate specific capacitance of the fiber‐shaped supercapacitor reached 11.09 F g−1 at a current of 2 mA and outstanding cycling stability with about 93.5 % retention at 4 mA after 4000 charge/discharge cycles. Furthermore, the flexible fiber supercapacitor does not show any apparent degradation in the bending test, illustrating its potential to be used in portable and wearable energy‐storage devices.
A Non‐Invasive NMR Method Based on Histidine Imidazoles to Analyze the pH‐Modulation of Protein–Nucleic Acid Interfaces
Authors: Cruz‐Gallardo Isabel , Del Conte Rebecca , Velázquez‐Campoy Adrián , García‐Mauriño Sofía M. , Díaz‐Moreno Irene 
Published: April 2015

AbstractA useful 2J(NH) coupling‐based NMR spectroscopic approach is proposed to unveil, at the molecular level, the contribution of the imidazole groups of histidines from RNA/DNA‐binding proteins on the modulation of binding to nucleic acids by pH. Such protonation/deprotonation events have been monitored on the single His96 located at the second RNA/DNA recognition motif (RRM2) of T‐cell intracellular antigen‐1 (TIA‐1) protein. The pKa values of the His96 ionizable groups were substantially higher in the complexes with short U‐rich RNA and T‐rich DNA oligonucleotides than those of the isolated TIA‐1 RRM2. Herein, the methodology applied to determine changes in pKa of histidine side chains upon DNA/RNA binding, gives valuable information to understand the pH effect on multidomain DNA/RNA‐binding proteins that shuttle among different cellular compartments.
Photoisomerisation in Aminoazobenzene‐Substituted Ruthenium(II) Tris(bipyridine) Complexes: Influence of the Conjugation Pathway
Authors: Amar Anissa , Savel Paul , Akdas‐Kilig Huriye , Katan Claudine , Meghezzi Hacène , Boucekkine Abdou , Malval Jean‐Pierre , Fillaut Jean‐Luc 
Published: April 2015

AbstractTransition‐metal complexes containing stimuli‐responsive systems are attractive for applications in optical devices, photonic memory, photosensing, as well as luminescence imaging. Amongst them, photochromic metal complexes offer the possibility of combining the specific properties of the metal centre and the optical response of the photochromic group. The synthesis, the electrochemical properties and the photophysical characterisation of a series of donor–acceptor azobenzene derivatives that possess bipyridine groups connected to a 4‐dialkylaminoazobenzene moiety through various linkers are presented. DFT and TD‐DFT calculations were performed to complement the experimental findings and contribute to their interpretation. The position and nature of the linker (ethynyl, triazolyl, none) were engineered and shown to induce different electronic coupling between donor and acceptor in ligands and complexes. This in turn led to strong modulations in terms of photoisomerisation of the ligands and complexes.
Reaction Optimization, Scalability, and Mechanistic Insight on the Catalytic Enantioselective Desymmetrization of 1,1‐Diborylalkanes via Suzuki–Miyaura Cross‐Coupling
Authors: Sun Ho‐Yan , Kubota Koji , Hall Dennis G. 
Published: April 2015

AbstractA method for enantioselective desymmetrization of 1,1‐diborylalkanes through a stereoselective Pd‐catalyzed Suzuki–Miyaura cross‐coupling has been thoroughly optimized. The most effective ligand was found to be a α,α,α,α‐tetra‐aryl‐1,3‐dioxolane‐4,5‐dimethanol (TADDOL)‐derived phosphoramidite. Results show that in order to achieve high selectivity, a suitable balance between the sterics of the aryl groups and the amino group on the ligand must be achieved. While the base has been known to facilitate transmetallation in cross‐coupling reactions, mechanistic studies on this desymmetrization process reveal that the base, in the presence of KHF2, likely plays an additional role in the hydrolysis of the pinacol boronates to the corresponding boronic acids. Through an in depth optimization of the chiral ligand and mechanistic studies, it was possible to obtain ee values over 90 % for several aryl bromides and to develop a reliably scalable process (up to one gram of 1,1‐diborylalkane substrate).
Towards Solar Energy Storage in the Photochromic Dihydroazulene–Vinylheptafulvene System
Authors: Cacciarini Martina , Skov Anders B. , Jevric Martyn , Hansen Anne S. , Elm Jonas , Kjaergaard Henrik G. , Mikkelsen Kurt V. , Brøndsted Nielsen Mogens 
Published: April 2015

AbstractOne key challenge in the field of exploitation of solar energy is to store the energy and make it available on demand. One possibility is to use photochromic molecules that undergo light‐induced isomerization to metastable isomers. Here we present efforts to develop solar thermal energy storage systems based on the dihydroazulene (DHA)/vinylheptafulvene (VHF) photo/thermoswitch. New DHA derivatives with one electron‐withdrawing cyano group at position 1 and one or two phenyl substituents in the five‐membered ring were prepared by using different synthetic routes. In particular, a diastereoselective reductive removal of one cyano group from DHAs incorporating two cyano groups at position 1 turned out to be most effective. Quantum chemical calculations reveal that the structural modifications provide two benefits relative to DHAs with two cyano groups at position 1: 1) The DHA–VHF energy difference is increased (i.e., higher energy capacity of metastable VHF isomer); 2) the Gibbs free energy of activation is increased for the energy‐releasing VHF to DHA back‐reaction. In fact, experimentally, these new derivatives were so reluctant to undergo the back‐reaction at room temperature that they practically behaved as DHA to VHF one‐way switches. Although lifetimes of years are at first attractive, which offers the ultimate control of energy release, for a real device it must of course be possible to trigger the back‐reaction, which calls for further iterations in the future.
Gold(I)‐Catalyzed Selective Heterocyclization of Propargylic Thioureas: Mechanistic Study of Competitive Gold‐Activation Mode
Authors: Jiang Yu , Wei Yin , Tang Xiang‐Ying , Shi Min 
Published: April 2015

AbstractA new selective gold(I)‐catalyzed intramolecular heterocyclization of propargylic thioureas has been developed, efficiently affording two kinds of cycloadducts in moderate to excellent yields with a broad substrate scope. Further mechanistic investigations indicate that competitive different gold activation modes feature in these cyclization processes. Kinetic experiments reveal that the gold activation mode is influenced by the ligand of the gold catalyst and the reaction conditions.
Chemical Synthesis of Phosphorylated Ubiquitin and Diubiquitin Exposes Positional Sensitivities of E1‐E2 Enzymes and Deubiquitinases
Authors: Bondalapati Somasekhar , Mansour Wissam , Nakasone Mark A. , Maity Suman Kumar , Glickman Michael H. , Brik Ashraf 
Published: April 2015

AbstractModification of ubiquitin by phosphorylation extends the signaling possibilities of this dynamic signal, as it could affect the activity of ligases and the processing of ubiquitin chains by deubiquitinases. The first chemical synthesis of phosphorylated ubiquitin and of Lys63‐linked diubiquitin at the proximal, distal or both ubiquitins is reported. This enabled the examination of how such a modification alters E1‐E2 activities of the ubiquitination machinery. It is found that E1 charging was not affected, while the assembly of phosphorylated ubiquitin chains was differentially inhibited with E2 enzymes tested. Moreover, this study shows that phosphorylation interferes with the recognition of linkage specific antibodies and the activities of several deubiquitinases. Notably, phosphorylation in the proximal or distal ubiquitin unit has differential effects on specific deubiquitinases. These results support a unique role of phosphorylation in the dynamics of the ubiquitin signal.
Scandium‐Catalyzed Asymmetric 1,6‐Addition of 3‐Substituted Oxindoles to Linear Dienyl Ketones
Authors: Wang Zhen , Kang Tengfei , Yao Qian , Ji Jie , Liu Xiaohua , Lin Lili , Feng Xiaoming 
Published: April 2015

AbstractThe first example of a N,N′‐dioxide–ScIII‐catalyzed 1,6‐addition of 3‐substituted oxindoles to dienyl ketones has been developed. This procedure tolerates a relatively wide range of 3‐substituted oxindoles under mild conditions, facilitating the preparation of various chiral oxindoles with quaternary stereocenters. In addition, the reliable catalyst was found to be effective in the asymmetric 1,6‐addition of both δ‐unsubstituted and δ‐methyl‐substituted dienyl ketones, achieving excellent regioselectivities and enantioselectivities (up to>99 % ee).
Acid/Base‐Mediated Uptake and Release of Halide Anions with a Preorganized Aryl‐Triazole Foldamer
Authors: Zhao Wei , Wang Ying , Shang Jie , Che Yanke , Jiang Hua 
Published: April 2015

AbstractA new approach for the construction of artificial receptors capable of selectively uptake and release of halides to mimic the biological halide ions pumps is developed, in which the preorganized aryl‐triazole foldamer was designed to bear a resorcinolic group in the central strand as a switch regulator. By using 1,8‐diazabicyclo[5.4.0]undec‐7‐ene/picric acid as the trigger, the foldamer can be switched between “w”‐shape and helical conformation. Due to the large, half‐open cavity as well as the additional electrostatic repulsion between oxyanions and guest halide, the foldamer in “w”‐shape possesses a much weaker affinity for chloride, bromide, and iodide anions than those in the helical conformation in 6:94 (v/v) [D6]DMSO/CDCl3. When the foldamer and chloride ions have the same initial concentrations of 1 mM, 70 % chloride ions in the solution could be reversibly bound or released upon switching.
Orchestrating the Biosynthesis of an Unnatural Pyrrolysine Amino Acid for Its Direct Incorporation into Proteins Inside Living Cells
Authors: Ehrlich Michael , Gattner Michael J. , Viverge Bastien , Bretzler Johanna , Eisen David , Stadlmeier Michael , Vrabel Milan , Carell Thomas 
Published: April 2015

AbstractWe here report the construction of an E. coli expression system able to manufacture an unnatural amino acid by artificial biosynthesis. This can be orchestrated with incorporation into protein by amber stop codon suppression inside a living cell. In our case an alkyne‐bearing pyrrolysine amino acid was biosynthesized and incorporated site‐specifically allowing orthogonal double protein labeling.
Merger of Visible Light Induced Oxidation and Enantioselective Alkylation with a Chiral Iridium Catalyst
Authors: Wang Chuanyong , Zheng Yu , Huo Haohua , Röse Philipp , Zhang Lilu , Harms Klaus , Hilt Gerhard , Meggers Eric 
Published: April 2015

AbstractA single chiral octahedral iridium(III) complex is used for visible light activated asymmetric photoredox catalysis. In the presence of a conventional household lamp and under an atmosphere of air, the oxidative coupling of 2‐acyl‐1‐phenylimidazoles with N,N‐diaryl‐N‐(trimethylsilyl)methylamines provides aminoalkylated products in 61–93 % yields with high enantiomeric excess (90–98 % ee). Notably, the iridium center simultaneously serves three distinct functions: as the exclusive source of chirality, as the catalytically active Lewis acid, and as a central part of the photoredox sensitizer. This conceptionally simple reaction Scheme may provide new avenues for the green synthesis of non‐racemic chiral molecules.
ChemInform Abstract: Homoatomic Clustering in T4Ga5 (T = Ta, Nb, Ta/Mo): A Story of Reluctant Intermetallics Crystallizing in a New Binary Structure Type.
Authors: Fredrickson Rie T. , Kilduff Brandon J. , Fredrickson Daniel C. 
Published: April 2015

AbstractTa4Ga5, Nb4Ga5, and Ta3.86Mo0.14Ga5 are prepared from the elements (850—1100 °C, 198—700 h) and characterized by powder and single crystal XRD, EDS, electron probe microanalysis, and DFT electronic structure calculations.
ChemInform Abstract: Classical and Nonclassical Germanium Environments in High‐Pressure BaGe5.
Authors: Castillo Rodrigo , Carrillo‐Cabrera Wilder , Schwarz Ulrich , Grin Yuri 
Published: April 2015

AbstractThe high‐pressure modification of BaGe5 is obtained from a 1:5 molar mixture of Ba6Ge25 and Ba (multianvil press, 15 GPa, 1000‐1200 K, 2 h).
ChemInform Abstract: Cs8[Fe4S10] and Cs7[Fe4S8], Two New Sulfido Ferrates with Different Tetrameric Anions.
Authors: Schwarz Michael , Roehr Caroline 
Published: April 2015

AbstractCs8[Fe4S10] (I) and Cs7[Fe4S8] (II) are prepared from stoichiometric samples of Fe, S, and Cs2S2 (corundum crucible in autoclave, ≤ 1070 K, 12 h).
ChemInform Abstract: Syntheses, Structures, and Nonlinear‐Optical Properties of Metal Sulfides Ba2Ga8MS16 (M: Si, Ge).
Authors: Liu Bin‐Wen , Zeng Hui‐Yi , Zhang Ming‐Jian , Fan Yu‐Hang , Guo Guo‐Cong , Huang Jin‐Shun , Dong Zhen‐Chao 
Published: April 2015

AbstractThe new title compounds are synthesized by solid state reactions of Ba, Ga2S9, Ge (Si), and S in a molar ratio of 2:4:1:4 (quartz tubes, 300 °C for 5 h, 650 °C for 10 h, and 980 °C for 5 d) and characterized by single crystal XRD, IR and UV/VIS/NIR diffuse reflectance spectroscopy, second harmonic generation measurements, laser‐induced damage threshold measurements, and DFT electronic band structure calculations.
ChemInform Abstract: Crystal Structure and Ion Conductivity of a New Mixed‐Anion Phosphate LiMg3(PO4)P2O7.
Authors: Kim Sung‐Chul , Lee Mi‐Sun , Kang Jinyeong , Kim Young‐Il , Kim Seung‐Joo 
Published: April 2015

AbstractLiMg3(PO4)P2O7 is prepared by solid‐state reaction of a 1:3:3 molar mixture of Li2CO3, MgO, and (NH4)2HPO4 (1.
ChemInform Abstract: Crystal Cluster Growth and Physical Properties of the EuSbSe3 and EuBiSe3 Phases.
Authors: Forbes Scott , Tseng Yu‐Chih , Mozharivskyj Yurij 
Published: April 2015

AbstractCrystal clusters of EuSbSe3 and EuBiSe3 phases are prepared by solid state reactions of a 2:1:3 molar mixture of Eu, Sb2Se/Bi2Se3, and Se (C‐coated evacuated silica ampoules, complex heating schedule).
ChemInform Abstract: Hydrothermal Growth of Lanthanide Borosilicates: A Useful Approach to New Acentric Crystals Including a Derivative of Cappelenite.
Authors: Heyward Carla C. , McMillen Colin D. , Kolis Joseph W. 
Published: April 2015

AbstractThe series of non‐centrosymmetric crystals (VIII)—(X) is hydrothermally prepared from precursor barium borosilicate glasses (IV) and (VI) and characterized by single crystal XRD.