bluuebunny/crossref_metadata_2025_split huggingface dataset:
ChemInform Abstract: Scope and Limitations of a Modified Hantzsch Reaction for the Synthesis of Oxazole‐Dehydroamino Acid Derivatives from Dehydroamino Acid Amides.
Authors: Nagaya Akihiro , Yamagishi Yoji , Yonezawa Yasuchika , Akai Shoji , Shin Chung‐gi , Sato Ken‐ichi 
Published: May 2012

AbstractA series of oxazoles (III) is prepared in good yields by a Hantzsch‐type reaction of amides (I) with bromides (II) and a subsequent dehydration of intermediate 4,5‐dihydro‐1,3‐oxazol‐4‐ol derivatives.
ChemInform Abstract: Synthesis and Antitumor Evaluation of Some New 1,3,4‐Oxadiazole‐Based Heterocycles.
Authors: Bondock Samir , Adel Shymaa , Etman Hassan A. , Badria Farid A. 
Published: May 2012

AbstractA series of 1,3,4‐oxadiazole derivatives carrying different pharmacophores and heterocyclic rings that are relevant to potential antitumor and cytotoxic activities is synthesized starting from hitherto unreported 5‐cyanomethyloxadiazole (II).
ChemInform Abstract: Asymmetric Synthesis of Functionalized Chromans via a One‐Pot Organocatalytic Domino Michael—Hemiacetalization or —Lactonization and Dehydration Sequence.
Authors: Enders Dieter , Urbanietz Gregor , Hahn Robert , Raabe Gerhard 
Published: May 2012

AbstractThe sequence is highly diastereo‐ and enantioselective and produces different tricyclic heterocyclic scaffold as base structures of natural products.
ChemInform Abstract: Synthesis of Novel Vicinal Coumarin‐ and Oxindole‐Functionalized Dispiropyrrolidines and Dispiropyrrolizidines via [3 + 2]‐Cycloaddition Reactions.
Authors: Bakthadoss Manickam , Kannan Damodharan , Sivakumar Govindan 
Published: May 2012

AbstractThe adducts generated from isatin and sarcosine or L‐proline undergo [3 + 2] cycloaddition with (E)‐arylidene‐3,4‐dihydrocoumarins to yield polycyclic products with complete diastereoselectivity.
ChemInform Abstract: Investigation on Amino‐Heck Cyclization of 1‐(2‐Vinylcyclohexyl)ketone Diethyl Phosphinyloximes.
Authors: Tsao Sheng‐Wei , Zhu Jia‐Liang 
Published: May 2012

AbstractA variety of 1‐substituted tetrahydroisoquinolines, e.g. compounds (IV) and (VIII), is readily prepared by amino‐Heck cyclization of corresponding phosphinyl ketoximes (III) and (VII).
ChemInform Abstract: Novel Route to Spiropiperidines Using N‐Methyl‐4‐piperidone, Malononitrile and Electrophiles.
Authors: Lakshmi Neelakandan Vidhya , Josephine G. A. Suganya , Perumal Paramasivan T. 
Published: May 2012

AbstractN‐Methylpiperidinone (I) reacts with malononitrile to produce a dimeric intermediate which reacts with different carbonyl compounds to give polycyclic products with complete diastereoselectivity where applicable.
ChemInform Abstract: A Facile Synthesis of 2‐Alkyl‐3‐α‐carboxy‐α‐styryl/Heterylvinyl Quinazolin‐4(3H)‐ones and 3‐Arylidene/Heterylmethylidene‐4‐aroyl‐1h‐ [1,4]benzodiazepine‐2,5(3H,4H)‐diones and Their Transformation into Novel Heterocyclyl and Heterocyclo Analogues.
Authors: Gupta Poonam , Sharma Archana , Sharma R. L. 
Published: May 2012

AbstractCondensation of o‐aminobenzamide (I) with γ‐azlactones provides access to quinazoline [cf.
ChemInform Abstract: Synthesis of Novel Benzo[b]pyrazolo[1,5]diazepines.
Authors: Raker Joseph , Wang Yi , Pechulis Anthony D. , Haber James C. , Lynch Michael A. , Spring Stacey L. 
Published: May 2012

AbstractTwo novel benzodiazepine derivatives (VIII) and (XI) are synthesized from amino alcohol (V).
ChemInform Abstract: Asymmetric Synthesis of 2‐Alkyl‐3‐phosphonopropanoic Acid Derivatives via Rh‐Catalyzed Asymmetric Hydrogenation.
Authors: Luo Li‐Bin , Wang Dao‐Yong , Zhou Xiao‐Mao , Zheng Zhuo , Hu Xiang‐Ping 
Published: May 2012

AbstractThe commercially available ferrocene‐chiral diphosphine ligand FDP is highly effective for the hydrogenation of 3‐arylpropenoates to give the corresponding propanoates with up to 98% e.e.
ChemInform Abstract: Constrained Digold(I) Diaryls: Syntheses, Crystal Structures, and Photophysics.
Authors: Partyka David V. , Teets Thomas S. , Zeller Matthias , Updegraff James B. III , Hunter Allen D. , Gray Thomas G. 
Published: May 2012

AbstractBiphosphine digold halide complexes and arylboronic acids provide the desired digold diaryls (11 examples).
ChemInform Abstract: New Bisabolane Sesquiterpenoids from a Marine‐Derived Fungus Aspergillus sp. Isolated from the Sponge Xestospongia testudinaria.
Authors: Wang Chang‐Yun , et al. et al. 
Published: May 2012

AbstractThree new sesquiterpenoids, namely disydonols A (I), B (II), and C (III), are isolated and their structures elucidated.
Optimization algorithm of periodical cooperative spectrum sensing in cognitive radio
Authors: Liu Xin , Tan Xuezhi 
Published: May 2012

SUMMARYTo decrease the interference to the primary user (PU) and improve the detected performance of cognitive radio (CR), a single‐band sensing scheme wherein the CR periodically senses the PU by cooperative spectrum sensing is proposed in this paper. In this scheme, CR first senses and then transmits during each period, and after the presence of the PU is detected, CR has to vacate to search another idle channel. The joint optimization algorithm based on the double optimization is proposed to optimize the periodical cooperative spectrum sensing scheme. The maximal throughput and minimal search time can be respectively obtained through the joint optimization of the local sensing time and the number of the cooperative CRs. We also extend this scheme to the periodical wideband cooperative spectrum sensing, and the joint optimization algorithm of the numbers of the sensing time slots and cooperative CRs is also proposed to obtain the maximal throughput of CR. The simulation shows that the proposed algorithm has lower computational quantity, and compared with the previous algorithms, when SNR = 5 dB, the throughput and search time of the proposed algorithm can respectively improve 0.3 kB and decrease 0.4 s. The simulation also indicates that the wideband cooperative spectrum sensing can achieve higher throughput than the single‐band cooperative spectrum sensing. Copyright © 2012 John Wiley & Sons, Ltd.
Long‐Range Order in Layered Perovskite Salts – Structure and Magnetic Properties of [(CH3)2CHCH2NH3]2CuX4 (X = Cl, Br)
Authors: Willett Roger D. , Gómez‐García Carlos J. , Twamley Brendan 
Published: May 2012

AbstractThe synthesis, structure, and magnetic properties of two new layered perovskite‐type copper halide salts are reported. Dominant ferromagnetic coupling is observed with J/k = 14.58(1) and 21.5(4) K for the Cl and Br salts, respectively. For [(iBA)2CuCl4] (1); (iBA = isobutylammonium): P21/c with a = 13.9481(8) Å, b = 7.5061(4) Å, c = 7.5133(4) Å and β = 102.520(1)° with Z = 4. In this structure, planar CuCl42– ions are linked together into layers of corner‐sharing distorted octahedra. Ferromagnetic ordering occurs at Tc = 6.5 K for 1 with spin canting. Hysteresis loops show a coercive field of 2 mT with rapid saturation at 2 K that persists up to T = 9 K. The bromide salt is not isomorphous with the chloride salt, since an antiferromagnetic interaction is also found to be present. A structure consisting of a perovskite‐type ribbon decorated with distorted tetrahedral CuBr42– ions is proposed. In this structure, there is dominant ferromagnetic coupling within the central ribbons and antiferromagnetic coupling with the decorated CuBr42– ions. The long‐range order at 12.2 K is assumed to be within the ribbons, leading to a ferrimagnetic state with the decorated ribbons. A second ordering transition observed at Tc2 ≈ 6.8 K may be due to the onset of 3d ordering between the decorated ribbons. At 2 K, hysteresis is observed with a coercive field of 6.3 mT and a maximum magnetization value of about 0.45 μB, which is consistent with the proposed structure and magnetic coupling. Above 2 K, the coercive field decreases smoothly to zero at Tc2, then increases to a value of about 2 mT at Tc1, before gradually decreasing to zero near 30 K. The presence of hysteresis in the paramagnetic phases of the compounds is presumed to be due to large regions of highly correlated spins.
Cinchona Alkaloid Catalyzed Regio‐ and Enantioselective Allylic Amination of Morita–Baylis–Hillman Carbonates with Isatins
Authors: Zhao Mei‐Xin , Chen Ming‐Xiao , Tang Wen‐Hao , Wei Deng‐Ke , Dai Tong‐Lei , Shi Min 
Published: May 2012

AbstractAn efficient enantioselective allylic amination of Morita–Baylis–Hillman (MBH) carbonates derived from methyl acrylate and aromatic aldehydes with isatins has been realized in the presence of commercially available cinchona alkaloids. The allylic amination products were obtained in moderate‐to‐good yields (46–74 %) with moderate‐to‐good enantioselectivities (up to 89 % ee) under mild conditions. The synthetic utility of the amination products has been well demonstrated by the facile synthesis of methyl (3R,4R)‐10‐oxo‐4‐phenyl‐2,3,4,10‐tetrahydropyrimido[1,2‐a]indole‐3‐carboxylate.
CD200‐CD200R1 interaction contributes to neuroprotective effects of anandamide on experimentally induced inflammation
Authors: Hernangómez Miriam , Mestre Leyre , Correa Fernando G. , Loría Frida , Mecha Miriam , Iñigo Paula M. , Docagne Fabian , Williams Richard O. , Borrell José , Guaza Carmen 
Published: May 2012

AbstractThe endocannabinoid anandamide (AEA) is released by macrophages and microglia on pathological neuroinflammatory conditions such as multiple sclerosis (MS). CD200 is a membrane glycoprotein expressed in neurons that suppresses immune activity via its receptor (CD200R) mainly located in macrophages/microglia. CD200‐CD200R interactions contribute to the brain immune privileged status. In this study, we show that AEA protects neurons from microglia‐induced neurotoxicity via CD200‐CD200R interaction. AEA increases the expression of CD200R1 in LPS/IFN‐γ activated microglia through the activation of CB2 receptors. The neuroprotective effect of AEA disappears when microglial cells derive from CD200R1−/− mice. We also show that engagement of CD200R1 by CD200Fc decreased the production of the proinflammatory cytokines IL‐1β and IL‐6, but increased IL‐10 in activated microglia. In the chronic phases of Theiler's virus‐induced demyelinating disease (TMEV‐IDD) the expression of CD200 and CD200R1 was reduced in the spinal cord. AEA‐treated animals up‐regulated the expression of CD200 and CD200R1, restoring levels found in sham animals together with increased expression of IL‐10 and reduced expression of IL‐1β and IL‐6. Treated animals also improved their motor behavior. Because AEA up‐regulated the expression of CD200R1 in microglia, but failed to enhance CD200 in neurons we suggest that AEA‐induced up‐regulation of CD200 in TMEV‐IDD is likely due to IL‐10 as this cytokine increases CD200 in neurons. Our findings provide a new mechanism of action of AEA to limit immune response in the inflamed brain. © 2012 Wiley Periodicals, Inc.
Cultural Adaptation of the Difficulties in Emotion Regulation Scale: Reliability and Validity of an Italian Version
Authors: Giromini Luciano , Velotti Patrizia , de Campora Gaia , Bonalume Laura , Cesare Zavattini Giulio 
Published: May 2012

ObjectiveThe aim of this study was to evaluate the reliability and validity of an Italian version of the Difficulties in Emotion Regulation Scale (DERS; Gratz & Roemer, 2004).MethodThree studies were completed. First, factorial structure, internal consistency, and concurrent validity of our Italian version of the DERS were examined with a sample of 323 students (77% female; mean age 25.6). Second, test‐retest analyses were completed using a different sample of 61 students (80% female; mean age 24.7). Third, the scores produced by a small clinical sample of participants (N = 38; mean age = 24.2) affected by anorexia, binge eating disorder, or bulimia were compared to those of an age‐matched, nonclinical female sample (N = 38; mean age = 24.7).ResultsThe factorial structure replicated quite well the six‐factor structure proposed by Gratz and Roemer. The internal consistency and test‐retest reliability were adequate and comparable to previous findings. The validity was good, as indicated by both the concurrent validity analysis and the clinical‐nonclinical sample comparison.ConclusionsThese studies provide further support for the multidimensional model of emotion regulation postulated by Gratz and Roemer and strengthen the rationale for cross‐cultural utilization of the DERS. © 2012 Wiley Periodicals, Inc. J. Clin. Psychol. 00:1‐20, 2012.
Thermal effects and morphological aspects of human dentin surface irradiated with different frequencies of Er:YAG laser
Authors: Raucci‐neto Walter , Pécora Jesus Djalma , Palma‐dibb Regina Guenka 
Published: May 2012

AbstractThis study reports the effects on micromorphology and temperature rise in human dentin using different frequencies of Er:YAG laser. Sixty human dentin fragments were randomly assigned into two groups (n = 30): carious or sound dentin. Both groups were divided into three subgroups (n = 10), according to the Er:YAG laser frequency used: 4, 6, or 10 Hz (energy: 200 mJ; irradiation distance: 12 mm; and irradiation time: 20 s). A thermocouple adapted to the tooth fragment recorded the initial temperature value (°C); then, the temperature was measured after the end of the irradiation (20 s). Morphological analysis was performed using images obtained with scanning electron microscope. There was no difference between the temperatures obtained with 4 and 6 Hz; the highest temperatures were achieved with 10 Hz. No difference was observed between carious and sound dentin. Morphological analyses revealed that all frequencies promoted irregular surface in sound dentin, being observed more selectively ablation especially in intertubular dentin with tubule protrusion. The caries dentin presented flat surface for all frequencies used. Both substrates revealed absence of any signs of thermal damage. It may be concluded that the parameters used in this study are capable to remove caries lesion, having acceptable limits of temperature rise and no significant morphological alterations on dentin surface. Microsc. Res. Tech. 2012. © 2012 Wiley Periodicals, Inc.
Impact of total hip arthroplasty on pain, walking ability, and cardiovascular fitness
Authors: Horstmann Thomas , Vornholt‐Koch Sandra , Brauner Torsten , Grau Stefan , Mündermann Annegret 
Published: May 2012

AbstractWe tested the hypothesis that total hip arthroplasty (THA) patients have less pain and are able to walk longer post‐operatively than pre‐operatively, and that THA patients before and after have higher heart rates and compromised gas exchange determinants at rest and following exercise compared to healthy subjects with a post‐operative improvement. Fifty‐two patients completed questionnaires and an incremental walking stress test pre‐operatively and 6‐months after THA. Twenty‐four age‐matched control subjects completed the same stress test. Fifty‐one patients had less pain 6‐months after THA compared to pre‐operative levels. Forty‐three patients showed an improvement of at least one walking duration category. Patients had compromised cardiovascular fitness compared to the control group with a tendency to improve after THA. Hence, 6‐months following THA, deficits exist other than reduced strength as reported in the literature. Prior to THA, the ability to walk longer is compromised by pain and not by poor cardiovascular fitness. Studies on specific rehabilitation programs of varying intensities may demonstrate opportunities to improve the cardiovascular fitness of this population. © 2012 Orthopaedic Research Society. Published by Wiley Periodicals, Inc. J Orthop Res 30:2025–2030, 2012
Interfacial Polymerization of Polyanthranilic Acid: Morphology Controlled Synthesis
Authors: Gupta Bhavana , Prakash Rajiv 
Published: May 2012

AbstractFor the first time, the formation of hollow microspheres of the carboxyl functionalized self‐doped conducting polymer polyanthranilic acid (PANA), based on a two phase oxidative polymerization technique using two immiscible solvents, is reported. The spherical morphology of the functionalized polymer is obtained using mild acid and chloroform as immiscible solvents. The polymer is further investigated using FT‐IR, UV‐vis, electrochemical, TGA and X‐ray diffraction techniques and is compared with polyanthranilic acid formed using a one phase polymerization method. Unlike the amorphous, one phase synthesized polymer with a granular morphology, two phase polymerization provides a controlled hollow spherical morphology with higher thermal stability and crystallinity. The hollow nature of the sphere is further proven with TEM and controlled opening of the sphere by varying the pH above 7.
Synthesis and Characterization of PEG‐Based Drug‐Responsive Biohybrid Hydrogels
Authors: Gübeli Raphael J. , Ehrbar Martin , Fussenegger Martin , Friedrich Christian , Weber Wilfried 
Published: May 2012

AbstractInteractive materials being responsive to a biocompatible stimulus represent a promising approach for future therapeutic applications. In this study, we present a novel biohybrid material synthesized from biocompatible components being stimulus‐responsive to the pharmaceutically approved small‐molecule novobiocin. The hydrogel design is based on the gyrase B (GyrB) protein, which is covalently grafted to multi‐arm polyethylene glycol (PEG) using a Michael‐type addition reaction. Upon addition of the GyrB‐dimerizing substance coumermycin, stable hydrogels form which can be dissolved in a dose‐adjustable manner by the antibiotic novobiocin. The switchable properties of this PEG‐based hydrogel are favorable for future applications in tissue engineering and as externally controlled drug depot.
Strain fields and mechanical response of a highly to medium fissured bentonite clay
Authors: Vitone C. , Cotecchia F. , Viggiani G. , Hall S. A. 
Published: May 2012

SUMMARYThis article presents the developments of an ongoing research aimed at modelling the influence of fissuring on the behaviour of clays. In particular, it recalls the main results of an extensive laboratory investigation on a fissured bentonite clay from the south of Italy and presents the data of a new investigation on the evolution with shearing of the strain fields developing within the clay, resulting from Digital Image Correlation (DIC).Element test results are analysed in the framework of continuum mechanics and linked to the clay fissuring features, once characterised using the Fissuring IDentity (F‐ID) chart. This article compares the bentonite behaviour with that of other fissured clays of different F‐IDs, highlighting the common behavioural features.Thereafter, the soil response at the macro level is related to the DIC‐derived strain fields evolving within the clay with loading. For this purpose, DIC was successfully used to investigate the deformation processes active in the fissured clay and the sources of the localisation phenomena. DIC is shown to provide indications of the extent to which highly to medium fissured clays element test results can be of use to model the clay behaviour according to continuum mechanics. Copyright © 2012 John Wiley & Sons, Ltd.
Sildenafil reduces respiratory muscle weakness and fibrosis in the mdx mouse model of Duchenne muscular dystrophy
Authors: Percival Justin M , Whitehead Nicholas P , Adams Marvin E , Adamo Candace M , Beavo Joseph A , Froehner Stanley C 
Published: May 2012

AbstractDuchenne muscular dystrophy (DMD) is the most common form of muscular dystrophy caused by mutations in the dystrophin gene. Loss of dystrophin initiates a progressive decline in skeletal muscle integrity and contractile capacity which weakens respiratory muscles including the diaphragm, culminating in respiratory failure, the leading cause of morbidity and mortality in DMD patients. At present, corticosteroid treatment is the primary pharmacological intervention in DMD, but has limited efficacy and adverse side effects. Thus, there is an urgent need for new safe, cost‐effective, and rapidly implementable treatments that slow disease progression. One promising new approach is the amplification of nitric oxide–cyclic guanosine monophosphate (NO–cGMP) signalling pathways with phosphodiesterase 5 (PDE5) inhibitors. PDE5 inhibitors serve to amplify NO signalling that is attenuated in many neuromuscular diseases including DMD. We report here that a 14‐week treatment of the mdx mouse model of DMD with the PDE5 inhibitor sildenafil (Viagra®, Revatio®) significantly reduced mdx diaphragm muscle weakness without impacting fatigue resistance. In addition to enhancing respiratory muscle contractility, sildenafil also promoted normal extracellular matrix organization. PDE5 inhibition slowed the establishment of mdx diaphragm fibrosis and reduced matrix metalloproteinase‐13 (MMP‐13) expression. Sildenafil also normalized the expression of the pro‐fibrotic (and pro‐inflammatory) cytokine tumour necrosis factor α (TNFα). Sildenafil‐treated mdx diaphragms accumulated significantly less Evans Blue tracer dye than untreated controls, which is also indicative of improved diaphragm muscle health. We conclude that sildenafil‐mediated PDE5 inhibition significantly reduces diaphragm respiratory muscle dysfunction and pathology in the mdx mouse model of Duchenne muscular dystrophy. This study provides new insights into the therapeutic utility of targeting defects in NO–cGMP signalling with PDE5 inhibitors in dystrophin‐deficient muscle. Copyright © 2012 Pathological Society of Great Britain and Ireland. Published by John Wiley & Sons, Ltd.
Study on viscosity of polymer melt flowing through microchannels considering the wall‐slip effect
Authors: Zhao Danyang , Jin Yifei , Wang Minjie 
Published: May 2012

AbstractFor polymers with long, complicated, branched chains, it is difficult to measure the real shear viscosity and slip velocity, using the capillary rheometer based on the adsorption–desorption mechanism. In this study, a double‐barrel capillary rheometer was used to investigate the viscosities of four polymers including polypropylene, high‐density polyethylene, polystyrene, and polymethylmethacrylate in a microchannel. A general model of polymer viscosity based on the entanglement–disentanglement was presented. The proposed model is important in understanding the mechanism of wall slip. This general model can be transferred to the other different models when changing the parameters. Actually, the entanglement–disentanglement model can also be transformed to the adsorption–desorption model. Using the model, it was found that the viscosities of polystyrene and polymethylmethacrylate were reduced with decreasing die diameter, and the slip velocities were increased with the increase of shear stress which agrees well with polymer microrheology based on the microscale effect. For polymers with long, complicated, branched chains, the proposed model improves the accuracy of the calculated viscosity and gains the real slip velocity when polymer melt flows through a microchannel. POLYM. ENG. SCI., 2012. © 2012 Society of Plastics Engineers