bluuebunny/crossref_metadata_2025_split huggingface dataset:
QSAR studies on imidazothienopyrazines as IKK‐β inhibitors: from 2D to 3D
Authors: Long Wei , Liu Peixun , Li Xinru , Xu Yang , Yu Jie , Ma Shitang , Yu Lingling , Zou Zhongmei 
Published: April 2009

AbstractThis paper presents the investigation of quantitative structure‐activity relationship (QSAR) for imidazothienopyrazines from 2D to 3D, for assistance of developing new IKK‐β inhibitors. In 2D‐QSAR, we built linear and nonlinear models by heuristic method (HM) and Support Vector Machine (SVM) methods, respectively. The results (R2HM(training set) = 0.8775, R2SVM(training set) = 0.9356, R2HM(test set) = 0.6452, R2SVM(test set) = 0.8736) showed that the nonlinear model is more precise to predict the activities of imidazothienopyrazines. In 3D‐QSAR, Phase methodology was employed, resulting in a successful model for prediction of imidazothienopyrazines' bioactivities, and this model (R2(training set) = 0.9717, R2(test set) = 0.9209) is better than any one of 2D‐QSAR models, linear or nonlinear. In addition, the discussion of 2D descriptors from 2D‐QSAR and the 3D plots from Phase results provided suggestions and guidance to develop new compounds which may present better bioactivities against IKK‐β. Copyright © 2009 John Wiley & Sons, Ltd.
Achievable sum‐rate analysis of correlated two‐antenna MIMO uplink channels
Authors: Lee Jin‐Woo , Lee Yong‐Hwan 
Published: April 2009

AbstractThis paper analyzes the achievable sum‐rate of correlated two‐antenna multiple‐input multiple‐output (MIMO) uplink channels. Most of previous works have considered the case when a single user has multiple transmit antennas (i.e. multi‐antenna single‐user scenario). This paper considers the case when two‐antenna MIMO uplink channels comprise two users with a single transmit antenna (i.e. single‐antenna two‐user scenario). The analytic and simulation results show that the achievable sum‐rate of correlated single‐antenna two‐user MIMO uplink channels highly depends on the angle difference between the receive correlation coefficients of two users. It is also shown that the achievable sum‐rate of correlated single‐antenna two‐user MIMO uplink channels is larger than that of correlated two‐antenna single‐user MIMO uplink channels and can even be larger than that of independent and identically distributed Rayleigh two‐antenna MIMO uplink channels. Copyright © 2009 John Wiley & Sons, Ltd.
Abnormal glucose metabolism in heterozygous mutant mice for a type I receptor required for BMP signaling
Authors: Scott Gregory J. , Ray Manas K. , Ward Toni , McCann Kelly , Peddada Shyamal , Jiang Fang‐Xu , Mishina Yuji 
Published: April 2009

AbstractBMPRIA and its high‐affinity ligand BMP4 have recently been shown to be expressed in the β‐cells of the pancreas. Here, we report the abnormalities of heterozygous mice for Bmpr1a in glucose metabolism during the course of intraperitoneal glucose tolerance test. The heterozygous mice had increased blood glucose levels throughout the first 2.5 h after the administration of glucose. Analysis of glucose‐stimulated insulin secretion (GSIS) indicates that insulin secretion in the heterozygous mice is compromised, and induction of secreted insulin by stimulation is substantially lower compared with the wild‐type controls. No apparent abnormalities in pancreas, thyroid, and liver were seen upon histological examination. Real‐time PCR results of selected genes showed an increase in the mRNA level of Ins1 and Ins2 in the heterozygous group. These results indicate that the glucose‐sensing pathway in these heterozygous mice is altered because of the heterozygosity in Bmpr1a. Together, our data suggest that BMP signaling through BMPRIA plays an important role in glucose metabolism and possibly working through the GSIS pathway. genesis 47:385–391, 2009. © 2009 Wiley‐Liss, Inc.
Equilibrium and Kinetic Studies of the Reactions between Aqua[1‐(2‐aminoethyl)piperazine]palladium(II) and Biologically Relevant Nucleophiles
Authors: Soldatović Tanja , Shoukry Mohamed , Puchta Ralph , Bugarčić Živadin D. , van Eldik Rudi 
Published: April 2009

AbstractThe kinetics and mechanism of the complex‐formation reactions of [Pd(AEP)(H2O)]2+, where AEP stands for 1‐(2‐aminoethyl)piperazine, with biologically relevant ligands were studied as a function of selected nucleophiles and pH. The reactivity of the ligands follows the sequence L‐methionine > guanosine‐5′‐monophosphate > glycine > inosine >> glutathione. The substitution reactions with glutathione showed two reaction steps in which the first step involves coordination through nitrogen and depends on the nucleophile concentration, whereas the second step involves intramolecular isomerization from N‐ to S‐bonded glutathione and does not depend on the nucleophile concentration. The stoichiometry and stability constants of the formed complexes are also reported, and the concentration distribution of the various complex species was evaluated as a function of pH. The results are discussed in terms of the mechanism of antitumor activity of related platinum complexes.(© Wiley‐VCH Verlag GmbH & Co. KGaA, 69451 Weinheim, Germany, 2009)
Chemistry of Ring‐Fused Oxazine‐2,4‐diones
Authors: Brouillette Yann , Martinez Jean , Lisowski Vincent 
Published: April 2009

AbstractIsatoic anhydride has attracted a great deal of attention in the last decades. Substitution of its benzene moiety by many different ring systems has given rise to a large array of analogues. A review on the methods of preparation of all known ring‐fused oxazine‐2,4‐diones is given herein. The different reactivity of these analogues is exhaustively depicted andillustrates the rich versatility of this class of starting material.(© Wiley‐VCH Verlag GmbH & Co. KGaA, 69451 Weinheim, Germany, 2009)
New Cascade Syntheses of Nitronyl Nitroxides and a New Synthetic Approach to Imino Nitroxides
Authors: Tretyakov Eugene , Tolstikov Svyatoslav , Mareev Aleksander , Medvedeva Alevtina , Romanenko Galina , Stass Dmitry , Bogomyakov Artem , Ovcharenko Victor 
Published: April 2009

AbstractSuspensions of MxOy (MnO2, Co2O3, Ni2O3) in protic solvents (MeOH, EtOH) have been found to be suitable systems for use in a cascade transformation of 4,4,5,5‐tetramethyl‐2‐[2‐(trimethylsilyl)ethynyl]imidazolidine‐1,3‐diol (1a) into 2‐ethynyl‐4,4,5,5‐tetramethyl‐4,5‐dihydro‐1H‐imidazole‐1‐oxyl 3‐oxide (3). In MnO2/MeOH, the products of further transformation of 3, (Z)‐ and (E)‐2‐(2‐methoxyvinyl)‐4,4,5,5‐tetramethyl‐4,5‐dihydro‐1H‐imidazole‐1‐oxyl 3‐oxides, were obtained by the regiospecific addition of MeOH to the triple bond of 3. In the reaction in MnO2/MeOH+H2O (1:1), the Z isomer was the sole product. A multistep one‐pot transformation of 1 into 4,4,5,5‐tetramethyl‐2‐[2‐oxo‐1‐(4,4,5,5‐tetramethylimidazolidin‐2‐ylidene)ethyl]‐4,5‐dihydro‐1H‐imidazole‐1‐oxyl 3‐oxide occurred in MnO2/EtOH. For (E)‐2‐[2‐(diethylamino)vinyl]‐4,4,5,5‐tetramethyl‐4,5‐dihydro‐1H‐imidazole‐1‐oxyl 3‐oxide, it was shown that use of the MnO2/secondary amine system provided a one‐pot transformation of 1a and gave (E)‐aminovinyl‐substituted nitronyl nitroxide as the sole product. In combined MnO2/ROH/K2CO3 systems (R = Me, Et), the imidazolidine‐1,3‐diol 1a was transformed into (E)‐2‐(2‐ethoxyvinyl)‐4,4,5,5‐tetramethyl‐4,5‐dihydro‐1H‐imidazole‐1‐oxyl 3‐oxide and the acetals 2‐(2,2‐dimethoxyethyl)‐ and 2‐(2,2‐diethoxyethyl)‐4,4,5,5‐tetramethyl‐4,5‐dihydro‐1H‐imidazole‐1‐oxyl 3‐oxide. In MnO2/MeNO2 we obtained the products of the transformations of different 2‐substituted 4,4,5,5‐tetramethylimidazolidine‐1,3‐diols (R = C≡C–SiMe3, aryl, hetaryl, alkyl) or nitronyl nitroxides into the corresponding imino nitroxides (13 products); this reaction is a new method for the preparation of imino nitroxides and allowed us to synthesize the first α‐acetylenyl‐substituted imino nitroxides. The majority of paramagnetic compounds, including the derivatives of 1a, were obtained as perfect crystals, and their structures were determined by X‐ray structure analysis (14 solved structures). (© Wiley‐VCH Verlag GmbH & Co. KGaA, 69451 Weinheim, Germany, 2009)
Cationic Rhodium(I)/H8‐binap Complex Catalyzed [2+2+2] Cycloadditions of 1,6‐ and 1,7‐Diynes with Carbonyl Compounds
Authors: Otake Yousuke , Tanaka Rie , Tanaka Ken 
Published: April 2009

AbstractWe have established that a cationic rhodium(I)/H8‐binap complex catalyzes [2+2+2] cycloadditions of a variety of 1,6‐ and 1,7‐diynes with both electron‐deficient and electron‐rich carbonyl compounds, leading to dienones in high yield under mild reaction conditions. In the reactions with acyl phosphonates, the reactivity of 1,6‐ and 1,7‐diynes was highly dependent on their own structures. The addition of chelating diethyl oxalate effectively promoted the [2+2+2] cycloadditions involving acyl phosphonates, presumably due to the equilibrium formation of the desired 1:1 rhodium complex of the diyne and the acyl phosphonate by facile ligand exchange between the diyne and weakly coordinated diethyl oxalate. In the reactions involving bifunctional carbonyl compounds or unsymmetrical 1,6‐diynes, high chemo‐ or regioselectivities were observed.(© Wiley‐VCH Verlag GmbH & Co. KGaA, 69451 Weinheim, Germany, 2009)
Modeling monthly temperature data in Lisbon and Prague
Authors: Alpuim Teresa , El‐Shaarawi Abdel 
Published: April 2009

AbstractThis paper examines monthly average temperature series in two widely separated European cities, Lisbon (1856–1999) and Prague (1841–2000). The statistical methodology used begins by fitting a straight line to the temperature measurements in each month of the year. Hence, the 12 intercepts describe the seasonal variation of temperature and the 12 slopes correspond to the rise in temperature in each month of the year. Both cities show large variations in the monthly slopes. In view of this, an overall model is constructed to integrate the data of each city. Sine/cosine waves were included as independent variables to describe the seasonal pattern of temperature, and sine/cosine waves multiplied by time were used to describe the increase in temperature corresponding to the different months. The model also takes into account the autoregressive, AR(1), structure that was found in the residuals. A test of the significance of the variables that describe the variation of the increase in temperature shows that both Lisbon and Prague had an increase in temperature that is different according to the month. The winter months show a higher increase than the summer months. Copyright © 2009 John Wiley & Sons, Ltd.
Coupled Navier–Stokes—Molecular dynamics simulations using a multi‐physics flow simulation framework
Authors: Steijl R. , Barakos George N. 
Published: April 2009

AbstractSimulation of nano‐scale channel flows using a coupled Navier–Stokes/Molecular Dynamics (MD) method is presented. The flow cases serve as examples of the application of a multi‐physics computational framework put forward in this work. The framework employs a set of (partially) overlapping sub‐domains in which different levels of physical modelling are used to describe the flow. This way, numerical simulations based on the Navier–Stokes equations can be extended to flows in which the continuum and/or Newtonian flow assumptions break down in regions of the domain, by locally increasing the level of detail in the model. Then, the use of multiple levels of physical modelling can reduce the overall computational cost for a given level of fidelity. The present work describes the structure of a parallel computational framework for such simulations, including details of a Navier–Stokes/MD coupling, the convergence behaviour of coupled simulations as well as the parallel implementation. For the cases considered here, micro‐scale MD problems are constructed to provide viscous stresses for the Navier–Stokes equations. The first problem is the planar Poiseuille flow, for which the viscous fluxes on each cell face in the finite‐volume discretization are evaluated using MD. The second example deals with fully developed three‐dimensional channel flow, with molecular level modelling of the shear stresses in a group of cells in the domain corners. An important aspect in using shear stresses evaluated with MD in Navier–Stokes simulations is the scatter in the data due to the sampling of a finite ensemble over a limited interval. In the coupled simulations, this prevents the convergence of the system in terms of the reduction of the norm of the residual vector of the finite‐volume discretization of the macro‐domain. Solutions to this problem are discussed in the present work, along with an analysis of the effect of number of realizations and sample duration. The averaging of the apparent viscosity for each cell face, i.e. the ratio of the shear stress predicted from MD and the imposed velocity gradient, over a number of macro‐scale time steps is shown to be a simple but effective method to reach a good level of convergence of the coupled system. Finally, the parallel efficiency of the developed method is demonstrated. Copyright © 2009 John Wiley & Sons, Ltd.
Physico–chemical and in vitro biological study of zinc‐doped calcium sulfate bone substitute
Authors: Hesaraki Saeed , Nemati Roghayeh , Nazarian Hamid 
Published: April 2009

AbstractIn the present study, series of Zn incorporated calcium sulfate bone cements, with different amounts of doped Zn(0, 0.74, 1.97, 3.05, 4.21 wt %) were prepared by mixing a calcium sulfate hemihydrate powder and solutions of zinc sulfate, and the effect of zinc‐doping on some physical, physico–chemical, and biological properties of the cements were investigated. Pure calcium sulfate cement was also made as control, with the mentioned powder and distilled water as liquid phase. The initial setting time and compressive strength of the cement significantly changed from 17 min and 3.2 MPa for the pure calcium sulfate to 6 min and 6 MPa for the Zn‐added calcium sulfate, respectively. Compared to pure calcium sulfate, more gypsum precipitates were formed in the zinc sulfate added samples with a morphology of thin, elongated, and rod‐shaped crystals. The biological properties of the samples were analyzed in the terms of cell viability and cell activity on human osteosarcoma (G‐292) using MTT assay and alkaline phosphatase (ALP) activity in the cell culture medium. The best increased cell density and ALP activity were achieved for the calcium sulfate cement with a content of 0.74 wt % Zn, whereas a toxic behavior was observed for the samples with Zn concentrations more than 1.97%. © 2009 Wiley Periodicals, Inc. J Biomed Mater Res Part B: Appl Biomater, 2009
Stability of climate signal in carbon and oxygen isotope records and ring width from Scots pine (Pinus sylvestris L.) in Finland
Authors: Hilasvuori Emmi , Berninger Frank , Sonninen Eloni , Tuomenvirta Heikki , Jungner Högne 
Published: April 2009

AbstractFour hundred year long records of carbon and oxygen stable isotope ratios and ring width were measured from Scots pine (Pinus sylvestris L.) from sites in Northern and Eastern Finland. Responses of isotope ratios to temperature and precipitation were analysed for the 20th century. Carbon isotope ratios responded strongly to summer temperature at both sites, whereas an influence of precipitation on the record was observed only at the site in Eastern Finland. Oxygen isotope ratios were less responsive to climatic variation than carbon at the high‐frequency level. To shed light on the role of the possible divergence problem during last decades the climate responses were studied separately in the first and in the second half of the 20th century. The responses to temperature were stable in the north but in Eastern Finland the significant period of summer occurred earlier during the later half of the century. Relationships between records were studied during the 400 a period. All proxies correlated positively with each other, although temporal changes occurred. Common forcing, discovered in Northern Finland between carbon isotope and ring width records, was weaker in the earlier period studied. Three climate reconstructions were created: temperature reconstruction for Northern Finland and temperature and precipitation reconstructions for Eastern Finland. Copyright © 2009 John Wiley & Sons, Ltd.
The last deglaciation in the Picos de Europa National Park (Cantabrian Mountains, northern Spain)
Authors: Moreno Ana , Valero‐Garcés Blas L. , Jiménez‐Sánchez Montserrat , Domínguez‐Cuesta María José , Mata M. Pilar , Navas Ana , González‐Sampériz Penélope , Stoll Heather , Farias Pedro , Morellón Mario , Corella J. Pablo , Rico Mayte 
Published: April 2009

AbstractA sedimentological and geochemical study of the Lago Enol sequence (Cantabrian Mountains, northern Spain), together with detailed geomorphological mapping, provides a first record of glacier evolution and climate change over the last 40 ka in the Picos de Europa National Park. The Enol glacier retreated from its maximum extent prior to 40 ka BP as demonstrated by the onset of proglacial lacustrine sedimentation in two glaciated depressions: the Comella hollow to the north (before 40 ka BP) and the Lago Enol (before 38 ka BP). These results support previous evidence that the maximum extent of southern European glaciers occurred earlier than in northern Europe. Alternation of homogeneous and laminated proglacial sediments during the glacier retreat illustrate a dynamic glacial evolution during the Marine Isotope Stage (MIS) 3 (40–26 ka BP). A slight warming is detected at 26 ka ago with the change from proglacial sediments (in a lake located in contact to the glacier) to glaciolacustrine sedimentation (in a non‐contact or distal lake). Finally, the onset of organic‐rich sediments took place at 18 ka ago. This last transition occurred in two phases, similarly to the North Atlantic Last Termination, suggesting a link between North Atlantic Deep Water formation oscillations and palaeohydrological variability in the Cantabrian Mountains. Copyright © 2009 John Wiley & Sons, Ltd.
FT‐IR, FT‐Raman and DFT calculations of the salicylanilide derivate 4‐chloro‐2‐(4‐bromophenylcarbamoyl)phenyl acetate
Authors: Varghese Hema Tresa , Panicker C. Yohannan , Madhavan V.S. , Mathew Samuel , Vinsova Jarmila , Van Alsenoy Christian 
Published: April 2009

AbstractFT‐IR and FT‐Raman spectra of 4‐chloro‐2‐(4‐bromophenylcarbamoyl)phenyl acetate were recorded and analyzed. The vibrational wavenumbers and corresponding vibrational assignments were examined theoretically using the Gaussian03 set of quantum chemistry codes. The red shift of the NH stretching wavenumber in the infrared (IR) spectrum from the computed wavenumber indicates the weakening of the NH bond resulting in proton transfer to the neighbouring oxygen atom. The simultaneous IR and Raman activations of the CO stretching mode give the charge transfer interaction through a π‐conjugated path. Optimized geometrical parameters of the title compound are in agreement with similar reported structures. From the optimized structure, it is clear that the hydrogen bonding decreases the double bond character of CO bond and increases the double bond character of the CN bonds. The first hyperpolarizability, predicted infrared intensities and Raman activities are reported. The calculated first hyperpolarizability is comparable with the reported values of similar derivatives and is an attractive object for future studies of non‐linear optics. The assignments of the normal modes are done by potential energy distribution (PED) calculations. Copyright © 2009 John Wiley & Sons, Ltd.
Ten‐year results of cartilage palisades versus fascia in eardrum reconstruction after surgery for sinus or tensa retraction cholesteatoma in children
Authors: Cayé‐Thomasen Per , Andersen Janne , Uzun Cem , Hansen Søren , Tos Mirko 
Published: April 2009

AbstractObjectives/Hypothesis:To compare cartilage palisades with fascia grafting in reconstruction of the eardrum after surgery for sinus or tensa retraction cholesteatoma in children, with respect to long‐term postoperative eardrum retraction and perforation, cholesteatoma recurrence, and hearing acuity.Methods:A total of 64 children underwent surgery for either sinus or tensa retraction cholesteatoma during the period 1995 to 2000 (mean age 9 years, range 5–15). The eardrum was reconstructed using cartilage palisades in 32 children (32 ears) and fascia or perichondrium in 32 children (33 ears). The patients were followed for at least one year postoperatively and re‐evaluated 4 years after surgery, and again recently at a mean of 10 years. The main outcome measures were postoperative drum retraction and perforation, cholesteatoma recurrence, and hearing acuity (pure tone average, speech reception threshold, and pure tone air‐bone gap).Results:All but two patients in both groups attended the 10‐year follow‐up examination (94% attendance). The mean overall follow‐up period was 119 months (115 months in the palisade and 125 months in the fascia group). Total number of retractions during follow‐up and at the 10‐year examination was six (19%) for the palisade group and 14 (42%) for the fascia group (P = .03; chi‐square test). The accumulated numbers for a perforation were four (13%) for the palisade group and seven (21%) for the fascia group (difference not significant). Two residual cholesteatomas, which are not related to the graft material, occurred in the palisade group (6%), whereas both recurrencies, which may be related to the graft material, occurred in the fascia group (6%). The hearing acuity for children operated on for a sinus cholesteatoma and for children with type III tympanoplasties was significantly better when cartilage palisade grafting had been employed.Conclusions:The cartilage palisade grafting technique appears superior with respect to prevention of long‐term eardrum retraction. The occurrence of cholesteatoma recurrency and eardrum perforation seem to be independent of grafting material, although these results may be due to type 2 error (low number of ears). In sinus cholesteatoma surgery and in type III tympanoplasty, the long‐term hearing results appear better when grafting cartilage palisades. Laryngoscope, 2009
Carcinoma of the nasal cavity and paranasal sinuses
Authors: Mendenhall William M. , Amdur Robert J. , Morris Christopher G. , Kirwan Jessica , Malyapa Robert S. , Vaysberg Mikhail , Werning John W. , Mendenhall Nancy P. 
Published: April 2009

AbstractObjectives/Hypothesis:To determine the outcomes after radiotherapy (RT) alone or combined with surgery at the University of Florida for patients with carcinomas of the nasal cavity and paranasal sinuses.Methods:Between November 1964 and June 2005, 109 patients were treated with curative intent. Patients with maxillary sinus carcinomas were excluded. Fifty‐six patients were treated with definitive RT, and 53 patients received surgery and preoperative (eight patients) or postoperative (45 patients) RT. Median follow‐up was 4.3 years (range, 0.2–35.9 years). Median follow‐up on living patients was 9.4 years (range, 2.0–35.9 years).Results:The 5‐year local control rates were: T1‐T3, 82%; T4, 50%; and overall, 63%. Local control at 5 years was 43% after definitive RT versus 84% after surgery and adjuvant RT (P< .0001). Multivariate analysis of local control revealed that both overall stage and treatment group (definitive RT versus surgery and adjuvant RT) significantly impacted this endpoint. Cause‐specific survival rates were: stages I to III, 81%; stage IV, 54%; and overall, 62%. Multivariate analysis revealed that T‐stage, N‐stage, and treatment group significantly influenced this endpoint. Thirty‐one (20%) of 109 patients sustained severe complications; 17 of 56 patients (16%) after definitive RT and 14 of 53 patients (25%) after surgery and adjuvant RT.Conclusions:The probability of local control and cause‐specific survival is better after surgery and RT compared with definitive RT. There is a modest increase in the risk of complications after surgery and RT. Thus, the preferred treatment is surgery combined with preoperative or postoperative RT. Laryngoscope, 2009