bluuebunny/crossref_metadata_2025_split huggingface dataset:
Density Functional Theoretical Analysis of the Molecular Structural Effects on Raman Spectra of β‐Carotene and Lycopene
Authors: Liu Weilong , Wang Zhigang , Zheng Zhiren , Jiang Lilin , Yang Yanqiang , Zhao Liancheng , Su Wenhui 
Published: October 2012

AbstractThe molecular structural and Raman spectroscopic characteristics of β‐carotene and lycopene are investigated by density functional calculations. The effects of molecular structure and solvent environment on the Raman spectra are analyzed by comparing the calculated and measured results. It is found that the B3LYP/6‐31G(d) method can predict the reasonable result for β‐carotene, but the ν1 Raman activities of lycopene overflow at all the used theoretical methods because of the longer conjugation length. The calculated results indicate that the rotation of β‐rings in β‐carotene impedes the delocalization of π‐electrons, shortens the effective conjugation length, and results in higher frequency and lower activity of the ν1 mode in β‐carotene than lycopene. The measured ν1 bands of β‐carotene and lycopene shift respectively to higher and lower frequencies in solution compared with that in crystals since the crystal packing forces can lead to different conformational variations in the carotenoids molecules. The polarized continuum model theoretical analysis suggests that solvent has slight (significant) effects on the Raman frequencies (intensities) of both carotenoids.
Group IV M‐POSS (M=Zr, Hf) Coordination Polymers
Authors: Wei Zhijun , Ren Hongbo , Zhang Lin , Luo Meiming 
Published: October 2012

AbstractThe synthesis and characterization of Zr‐POSS and Hf‐POSS coordination polymers were reported. The IR data and the solid‐state 29Si MAS NMR indicated the existence of SiOM linkage. The polarized optical microscopy images and the XRD data suggested their crystalline nature.
A General and Efficient CuBr2‐Catalyzed N‐Arylation of Secondary Acyclic Amides
Authors: Wang Mangang , Yu Hua , You Xinwen , Wu Jun , Shang Zhicai 
Published: October 2012

AbstractA general and efficient Cu(II)‐catalyzed cross‐coupling method is reported for the preparation of acyclic tertiary amides. Generally moderate to excellent yields and functional group tolerance were obtained with secondary acyclic amides and aryl halides as substrates in toluene.
Tetrahydropyranylation of Alcohols and Phenols Using Polystyrene Supported Lewis Acids as Catalysts
Authors: Zhang Yi , Dou Qianqian , Liu Yuan , Dai Liyan , Wang Xiaozhong , Chen Yingqi 
Published: October 2012

AbstractPolystyrene supported TiCl4 (Ps‐TiCl4) and polystyrene supported FeCl3 (Ps‐FeCl3) were prepared by coordinating Lewis acids with polystyrene. The catalysts were characterized by TGA, BET, SEM, IR and pyridine‐adsorbed IR. The loading of Ps‐TiCl4 and Ps‐FeCl3 were 0.35 and 0.3 mmol·g−1 respectively. Both catalysts were found to be efficient for the tetrahydropyranylation and detetrahydropyranylation of various alcohols and phenols in different solvents. Two catalysts can be recovered and reused for five times with good activity.
Molecular Design of D‐π‐A Type II Organic Sensitizers for Dye Sensitized Solar Cells
Authors: Li Shifeng , Yang Xichuan , Qu Dingfeng , Wang Weihan , Wang Yu , Sun Licheng 
Published: October 2012

AbstractFour new type II organic dyes with D‐π‐A structure (donor‐π‐conjugated‐acceptor) and two typical type II sensitizers based on catechol as reference dyes are synthesized and applied in dye sensitized solar cells (DSCs). The four dyes can be adsorbed on TiO2 through hydroxyl group directly. Electron injection can occur not only through the anchoring group (hydroxyl group) but also through the electron‐withdrawing group (CN) located close to the semiconductor surface. Experimental results show that the type II sensitizers with a D‐π‐A system obviously outperform the typical type II sensitizers providing much higher conversion efficiency due to the strong electronic push‐pull effect. Among these dyes, LS223 gives the best solar energy conversion efficiency of 3.6%, with Jsc=7.3 mA·cm−2, Voc=0.69 V, FF=0.71, the maximum IPCE value reaches 74.9%.
Palladium‐Catalyzed Suzuki‐Miyaura Type Coupling Reaction of Aryl Halides with Triphenylborane‐Pyridine
Authors: Yang Minghua , Gu Yongbing , Wang Yan , Zhao Xiyu , Yan Guobing 
Published: October 2012

AbstractThe Suzuki‐Miyaura type coupling reaction of aryl halides with triphenylborane‐pyridine was described. The reaction can be catalyzed by Pd(OAc)2 (5 mol%) in presence of Cs2CO3 at 50°C or 80°C, and functionalized biaryls were obtained in good to excellent yields. This protocol is general and can tolerate a wide range of functional groups.
Novel Synthetic Route to α‐Aminophosphonates Containing Benzothiazole Moiety
Authors: Gu Liju , Wang Rui , Huang Xiangzhong , Jin Cheng 
Published: October 2012

AbstractA novel and ef?cient synthetic route to α‐aminophosphonates containing benzothiazole moiety via a cascade three‐component reaction from conveniently available starting materials has been developed. The target compounds 3a–3g, 7 and 8a, 8b were evaluated for their anticancer activities against the cancer cell line HL‐60 in vitro by the MTT method. Compound 3g showed good cancer inhibitory activity against the tested cell line. Further study is necessary to find out the potential antitumor activities.
Design of microstrip‐based surface coils for low‐field small‐bore MR applications
Authors: Seo Youngseob 
Published: October 2012

AbstractMicrostrip transmission line concept, which has been used to construct microwave integrated circuits or high frequency (≥300 MHz) antennas, is introduced to surface receive coils for use in a small volume coil at 1T and the feasibility of the microstrip‐based coils is investigated. Both single‐turn and two‐turn microstrip receive coils are fabricated. The size of the square shaped coil loop is 2.5 × 2.5 cm2. A lengthening inductor (toroid) is used to replace a long coaxial cable (=217 cm) needed for low‐field small‐bore MR applications. The lengthening inductor, matching, and tuning capacitors are located outside the magnet. One pulse and a gradient reversed form of FISP sequences are used to acquire NMR signals and MR images of gel phantoms, respectively. MR images acquired by the two‐turn coil have higher SNR and more uniform signal intensity than those obtained by the single‐turn coil and the volume coil. A novel, easy, and efficient method to design small microstrip‐based RF surface receive coils is developed and tested for low‐field small‐bore MR applications. © 2012 Wiley Periodicals, Inc. Concepts Magn Reson Part B (Magn Reson Engineering) 41B: 111–119, 2012
A novel method for coil efficiency estimation: Validation with a 13C birdcage
Authors: Giovannetti Giulio , Frijia Francesca , Hartwig Valentina , Menichetti Luca , De Marchi Daniele , Positano Vincenzo , Landini Luigi , Lombardi Massimo , Santarelli Maria Filomena , Ardenkjaer‐Larsen Jan Henrik 
Published: October 2012

AbstractCoil efficiency, defined as the B1 magnetic field induced at a given point on the square root of supplied power P, is an important parameter that characterizes both the transmit and receive performance of the radiofrequency (RF) coil. Maximizing coil efficiency will maximize also the signal‐to‐noise ratio. In this work, we propose a novel method for RF coil efficiency estimation based on the use of a perturbing loop. The proposed method consists of loading the coil with a known resistor by inductive coupling and measuring the quality factor with and without the load. We tested the method by measuring the efficiency of a 13C birdcage coil tuned at 32.13 MHz and verified its accuracy by comparing the results with the nuclear magnetic resonance nutation experiment. The method allows coil performance characterization in a short time and with great accuracy, and it can be used both on the bench and inside the scanner. © 2012 Wiley Periodicals, Inc. Concepts Magn Reson Part B (Magn Reson Engineering) 41B: 139–143, 2012
Bortezomib, melphalan, and prednisone in elderly patients with relapsed/refractory multiple myeloma
Authors: Petrucci Maria Teresa , Levi Anna , Bringhen Sara , Scotti Simona , Gentilini Fabiana , Russo Simone , Siniscalchi Agostina , Larocca Alessandra , Grammatico Sara , Boccadoro Mario , Foà Robin , Palumbo Antonio 
Published: October 2012

AbstractBACKGROUND:In elderly patients with newly diagnosed multiple myeloma (MM), the addition of bortezomib to standard, combined oral melphalan and prednisone (MP) significantly increases the response rate and event‐free survival compared with MP alone.METHODS:In this phase 1/2 trial, the authors assessed the dosing, efficacy, and safety of a lower dose‐intensity MP schedule plus weekly bortezomib as salvage treatment for elderly patients with MM. To assess the maximum tolerated dose, 19 patients who had relapsed/refractory MM after 1 or 2 lines of treatment entered the first phase of the study. They received melphalan at a dose of 24 mg for 28 days; bortezomib 1.3 mg/m2on days 1, 8, 15, and 22; and prednisone at a dose of 50 mg every other day of a 28‐day cycle for a total of 9 cycles. At the end of the first phase, based on the good efficacy and acceptable toxicity of this combination, an additional 23 patients were enrolled.RESULTS:After a median follow‐up of 21 months, of 42 patients who relapsed, 24 (57%) obtained at least a partial response, 4 had stable disease, and 11 had progressive disease. The median time to progression was 18 months, and the median overall survival was 30 months. Grade 3 and 4 toxicity was observed in 16 of 42 patients (38%) and was more frequent during the early cycles.CONCLUSIONS:A weekly infusion of bortezomib associated with lower dose‐intensity MP induced a high proportion of responses and was well tolerated in elderly patients with relapsed/refractory MM. Cancer 2013. © 2012 American Cancer Society.
Two days of antithymocyte globulin are associated with a reduced incidence of acute and chronic graft‐versus‐host disease in reduced‐intensity conditioning transplantation for hematologic diseases
Authors: Crocchiolo Roberto , Esterni Benjamin , Castagna Luca , Fürst Sabine , El‐Cheikh Jean , Devillier Raynier , Granata Angela , Oudin Claire , Calmels Boris , Chabannon Christian , Bouabdallah Réda , Vey Norbert , Blaise Didier 
Published: October 2012

AbstractBACKGROUND:The optimal combination of fludarabine, busulfan, and antithymocyte globulin (ATG) for reduced‐intensity conditioning (RIC) transplantation has not been established. ATG plays a pivotal role in the prevention of graft‐versus‐host disease (GvHD), but it is associated with a higher relapse rate and an elevated incidence of infections when high doses are used.METHODS:The authors retrospectively compared 2 different doses of ATG combined with fludarabine and busulfan in 229 adult patients who underwent transplantation at their institution. ATG was administered over 1 day (FBA1) or over 2 days (FBA2) at a daily dose of 2.5 mg/kg.RESULTS:There were 124 patients in the FBA2 cohort and 105 patients in the FBA2 cohorts. Patients in the FBA2 cohort were older and more frequently underwent transplantation from an unrelated donor; 93% of patients in the FBA2 cohort received intravenous busulfan versus only 5% in the FBA1 cohort. The incidence of grade 2 through 4 acute GvHD was 23% in the FBA2 cohort versus 42% in the FBA1 cohort (P= .002); the incidence of grade 3 through 4 acute GvHD was 10% versus 23%, respectively (P= .006); and the incidence of chronic GvHD was 35% versus 69%, respectively (P< .0001). The 2‐year rates of overall survival, nonrelapse mortality, and relapse/progression for the FBA1 and FBA2 cohorts were 65% versus 67%, respectively (P= .99), 20% versus 19%, respectively (P= .61), and 30% versus 19%, respectively (P= .09). The results were confirmed in multivariate analysis.CONCLUSIONS:The use of ATG at a dose of 5 mg/kg was correlated significantly with reduced incidence and severity of GvHD without impairing disease control. Taken together, the current results suggest that this conditioning represents a step forward in the optimization of RIC. Cancer 2013. © 2012 American Cancer Society.
Thyroid transcription factor‐1 expression is an independent predictor of recurrence and correlates with the IASLC/ATS/ERS histologic classification in patients with stage I lung adenocarcinoma
Authors: Kadota Kyuichi , Nitadori Jun‐ichi , Sarkaria Inderpal S. , Sima Camelia S. , Jia Xiaoyu , Yoshizawa Akihiko , Rusch Valerie W. , Travis William D. , Adusumilli Prasad S. 
Published: October 2012

AbstractBACKGROUND:In the current study, the authors investigated whether thyroid transcription factor‐1 (TTF‐1) expression is correlated with the International Association for the Study of Lung Cancer (IASLC)/American Thoracic Society (ATS)/European Respiratory Society (ERS) classification and whether it stratifies patients with stage I lung adenocarcinoma with respect to disease recurrence.METHODS:Patients with stage I lung adenocarcinoma were classified according to the IASLC/ATS/ERS classification. Tissue microarrays were constructed and immunostaining for TTF‐1 was performed. A total of 452 cases were available for analysis. Tumors were dichotomized based on the intensity of nuclear TTF‐1 expression as negative (score of 0) or positive (score of 1–3). The cumulative incidence of recurrence (CIR) was used to estimate disease recurrence probabilities.RESULTS:TTF‐1 expression was identified in 92% of patients, including 100% of patients with minimally invasive or lepidic‐predominant adenocarcinoma, 94% of patients with acinar‐predominant adenocarcinoma, 98% of patients with papillary‐predominant adenocarcinoma, 93% of patients with micropapillary‐predominant adenocarcinoma, 86% of patients with solid‐predominant adenocarcinoma, 67% of patients with colloid‐predominant adenocarcinoma, and 47% of patients with invasive mucinous carcinoma. The CIR for patients with negative TTF‐1 expression (n = 34 patients; 5‐year CIR, 40%) was significantly higher than that for patients with positive TTF‐1 expression (n = 418 patients; 5‐year CIR, 15%) (P < .001). Among the patients with intermediate‐grade tumors, the CIR for patients with negative TTF‐1 expression (n = 16 patients; 5‐year CIR, 45%) was significantly higher than that for patients with positive TTF‐1 expression (n = 313 patients; 5‐year CIR, 14%) (P < .001). On multivariate analysis, negative TTF‐1 expression was found to be significantly correlated with an increased risk of disease recurrence (hazards ratio, 2.55; P = .009).CONCLUSIONS:TTF‐1 expression was found to be an independent predictor of disease recurrence, stratifying intermediate‐grade tumors into 2 prognostic subsets, and it correlates with the IASLC/ATS/ERS classification. Cancer 2013. © 2012 American Cancer Society.
Graphics processing unit acceleration of the red/black SOR method
Authors: Konstantinidis Elias , Cotronis Yiannis 
Published: October 2012

SUMMARYThis work presents our strategy, applied optimizations and results in our effort to exploit the computational capabilities of graphics processing units (GPUs) under the CUDA environment in order to solve the Laplacian PDE. The parallelizable red/black successive over‐relaxation (SOR) method was used. Additionally, a program for the CPU was developed as a performance reference. Various performance improvements were achieved by using optimization methods, which proved to provide significant speedup. Memory access patterns prove to be a critical factor in efficient program execution on GPUs and it is, therefore, appropriate to follow data reorganization to achieve the highest feasible memory throughput. The same approach exhibits performance benefits on the CPU version, as well. Eventually, a direct comparison of optimal versions’ performance was realized. A 10 × speedup was measured for the CUDA version on an NVidia GTX480 GPU (NVidia Corp, Sta. Clara, CA, USA), exceeding 142 GB/s bandwidth, over the single threaded CPU version when run on an Intel Core i7 2600K CPU. The results prove that the global memory cache added on recent GPU architectures assist achieving high performance without requiring to employ the special memory types provided by the GPU (i.e. shared, texture or constant memory). Copyright © 2012 John Wiley & Sons, Ltd.
Design and synthesis of 1,3‐dicapryloyl‐2‐acetylglycerol as molecular probe for triacylglycerol metabolism study
Authors: Lei Qiong , Lee Wilson Liangwei , Li Tianhu 
Published: October 2012

AbstractThe increasing number of health issues caused by obesity and lack of healthy and efficient fat substitutes require development on new fat substitute. This study proposes a new potential reduced‐calorie structured triacylglycerol (TAG) of “1,3‐medium‐chain, 2‐short‐chain triglycerides (MSM)” configuration, and the fat substitution method is based on the suppression of 2‐monoacylglycerol absorption into intestinal cells, which would decrease the recombination of TAG and reduce lipid absorption in the digestive tract. A molecular probe, 1,3‐dicapryloyl‐2‐acetylglycerol, is offered for nutritionists to conduct further study on its metabolism in human body. The synthesis method for this structured TAG starts from the lipase‐catalyzed esterification between glycerol and caprylic acid, yielding 1,3‐dicapryloylglycerol, and is followed by direct esterification with acetic anhydride to form 1,3‐dicapryloyl‐2‐acetylglycerol. Its structure is characterized by FTIR,1H NMR,13C NMR, and LC‐ESI‐MS.Practical application: This kind of pure structured triglyceride can function as a molecular probe for nutritionists to test its metabolism in human body and conduct further evaluation on their fat substitute potential. The synthesis method can also be easily adopted by food industry since it involves only two simple reaction steps.
Absolute Configuration of Highly Flexible Natural Products by the Solid‐State ECD/TDDFT Method: Ximaolides and Sinulaparvalides
Authors: Kurtán Tibor , Jia Rui , Li Yan , Pescitelli Gennaro , Guo Yue‐Wei 
Published: October 2012

AbstractThe quantum‐mechanical calculation of chiroptical properties such as electronic circular dichroism (ECD) is an increasingly popular tool for establishing the absolute configuration of organic compounds, including natural products. However, this approach is often limited by conformational flexibility, which can be overcome by considering the solid crystalline state instead of solution. By knowing the solid‐state geometry, one may employ it as the input structure for ECD calculations and then comparing this with the ECD spectrum measured on a microcrystalline sample. We report here the application of this solid‐state ECD approach to establish the absolute configuration of three natural products, namely ximaolide A, sinulaparvalide A and B; all display pronounced flexibility and belong to two families of compounds with remarkable biological activity. The present configurational assignment may also be extended to several analogues whose absolute configurations have not yet been reported.
Synthesis of Pyrimidine‐Modified NHC Ruthenium‐Alkylidene Catalysts and Their Application in RCM, CM, EM and ROMP Reactions
Authors: Wu Guang‐Long , Cao Sheng‐Li , Chen Jian , Chen Zili 
Published: October 2012

AbstractA new type of N‐heterocyclic carbene bearing ruthenium olefin metathesis catalyst was prepared through the incorporation of a chelated pyrimidinyl methylene subunit, in which electron‐rich substituents were attached to stabilize the ruthenium complexes. These catalysts were successfully used in various types of olefin metathesis reactions, including ring‐closing metathesis (RCM), cross‐metathesis (CM), enyne metathesis (EM), and ring‐opening metathesis polymerization (ROMP) reactions. The results therein showed that the presence of an electron‐deficient pyrimidine structure greatly enhanced the new NHC ruthenium complexes' catalytic activities.
A Potentiometric Sensor for Cd2+ Based on Carbon Nanotube Paste Electrode Constructed from Room Temperature Ionic Liquid, Ionophore and Silica Nanoparticles
Authors: Afkhami Abbas , Bagheri Hasan , Shirzadmehr Ali , Khoshsafar Hosein , Hashemi Pegah 
Published: October 2012

AbstractA novel and effective potentiometric sensor for the rapid determination of Cd2+ based on carbon paste electrode consisting of the room temperature ionic liquid 1‐butyl‐3‐methylimidazolium hexafluorophosphate, multiwalled carbon nanotubes, silica nanoparticles and ionophore was constructed. The prepared composite has a low potential drift, high selectivity and fast response time, which leads to a more stable potential signal. A linear dynamic range of 4.50×10−9–1.00×10−1 mol L−1 with a detection limit of 2.00×10−9 mol L−1 was obtained. The modified electrode was successfully applied to the accurate determination of trace amounts of Cd2+ in environmental and biological samples.
Nanomolar Determination of Penicillamine by Using a Novel Cobalt/Polyaniline/Carbon Paste Nanocomposite Electrode
Authors: Amiri Mandana , Nekoiean Khadijeh , Bezaatpour Abolfazl 
Published: October 2012

AbstractThe fabrication of cobalt/polyaniline nanocomposite was performed using a simple chemical method. It was characterized by using TEM and FTIR techniques. The nanocomposite was applied as a modifier in a carbon paste electrode for selective determination of penicillamine. Penicillamine reacts with emeraldine polyaniline by using 1,4, Michael addition reaction. It can decrease the voltammetric peak current of emeraldine polyaniline. The effects of pH and potential sweep rate on the response of the electrode were investigated. Differential pulse voltammetry was applied for quantitative determination. Dynamic linear ranges were obtained in the ranges of 1.0×10−8–1.0×10−7 mol L−1 and 1.0×10−9–1.0×10−8 mol L−1.
Hydroxyanthraquinones Carminic Acid and Chrysazin Anodic Oxidation
Authors: de Souza Gil Eric , de Oliveira Severino Carlos B. , de Oliveira‐Brett Ana Maria 
Published: October 2012

AbstractThe anodic oxidation of the hydroxyanthraquinones carminic acid (CA) and chrysazin (CR) was investigated. The oxidation of CA proceeds in a pH‐dependent cascade mechanism, concerning the hydroquinone, the catechol and the 3‐OH groups in the anthraquinone moiety. The oxidation of the hydroquinone following the catechol electron‐donating groups occurs first at low positive potentials, the 3‐OH group is oxidized irreversibly at a higher potential. The oxidation of CR is pH‐dependent and occurs in successive steps. Oxidation of the hydroquinone tautomer in the CR‐ring occurs first, and the symmetrical 1‐OH and 8‐OH groups are irreversibly oxidized at the same higher potential.
Porous Nanostructured Metals for Electrocatalysis
Authors: Guo Dao‐Jun , Ding Yi 
Published: October 2012

AbstractNanoporous metals have been used to enhance electrocatalysis. The origin of their capability is understood on the basis of enlarged surface area. On the other hand, the nanoconfined space of nanoporous metals can significantly affect the electrochemical efficiency. Moreover, molecular dynamics in nanoconfined spaces is capable of offering much more chances of interaction between a redox molecule and a metal surface. These unique properties come from simply nanoporous structure and suggest new opportunity to innovative electrocatalysts in the future. This review addresses recent advances in the field of nanoporous metals and discusses respective important electrocatalytic applications.