bluuebunny/crossref_metadata_2025_split huggingface dataset:
CuII Coordination Chemistry of Patellamide Derivatives: Possible Biological Functions of Cyclic Pseudopeptides
Authors: Comba Peter , Dovalil Nina , Gahan Lawrence R. , Haberhauer Gebhard , Hanson Graeme R. , Noble Christopher J. , Seibold Björn , Vadivelu Prabha 
Published: January 2012

AbstractTwo synthetic derivatives of the naturally occurring cyclic pseudooctapeptides patellamide A–F and ascidiacyclamide, that is, H4pat2, H4pat3, as well as their CuII complexes are described. These cyclic peptide derivatives differ from the naturally occurring macrocycles by the variation of the incorporated heterocyclic donor groups and the configuration of the amino acids connecting the heterocycles. The exchange of the oxazoline and thiazole groups by dimethylimidazoles or methyloxazoles leads to more rigid macrocycles, and the changes in the configuration of the side chains leads to significant differences in the folding of the cyclic peptides. These variations allow a detailed study of the various possible structural changes on the chemistry of the CuII complexes formed. The coordination of CuII with these macrocyclic species was monitored by high‐resolution electrospray mass spectrometry (ESI‐MS), spectrophotometric (UV/Vis) and circular dichroic (CD) titrations, and electron paramagnetic resonance (EPR) spectroscopy. Density functional theory (DFT) calculations and molecular mechanics (MM) simulations have been used to model the structures of the CuII complexes and provide a detailed understanding of their geometric preferences and conformational flexibility. This is related to the CuII coordination chemistry and the reactivity of the dinuclear CuII complexes towards CO2 fixation. The variation observed between the natural and various synthetic peptide systems enables conclusions about structure–reactivity correlations, and our results also provide information on why nature might have chosen oxazolines and thiazoles as incorporated heterocycles.
Borromean‐Entanglement‐Driven Assembly of Porous Molecular Architectures with Anion‐Modified Pore Space
Authors: Sun Jian‐Ke , Yao Qing‐Xia , Tian Yu‐Yang , Wu Lei , Zhu Guang‐Shan , Chen Rui‐Ping , Zhang Jie 
Published: January 2012

AbstractA series of metal–organic frameworks based on a flexible, highly charged Bpybc ligand, namely 1⋅Mn⊃OH−, 2⋅Mn⊃SO42−, 3⋅Mn⊃bdc2−, 4⋅Eu⊃SO42− (H2BpybcCl2=1,1′‐bis(4‐carboxybenzyl)‐4,4′‐bipyridinium dichloride, H2bdc=1,4‐benzenedicarboxylic acid) have been obtained by a self‐assembly process. Single‐crystal X‐ray‐diffraction analysis revealed that all of these compounds contained the same n‐fold 2D→3D Borromean‐entangled topology with irregular butterfly‐like pore channels that were parallel to the Borromean sheets. These structures were highly tolerant towards various metal ions (from divalent transition metals to trivalent lanthanide ions) and anion species (from small inorganic anions to bulky organic anions), which demonstrated the superstability of these Borromean linkages. This non‐interpenetrated entanglement represents a new way of increasing the stability of the porous frameworks. The introduction of bipyridinium molecules into the porous frameworks led to the formation of cationic surface, which showed high affinities to methanol and water vapor. The distinct adsorption and desorption isotherms of methanol vapor in four complexes revealed that the accommodated anion species (of different size, shape, and location) provided a unique platform to tune the environment of the pore space. Measurements of the adsorption of various organic vapors onto framework 1⋅Mn⊃OH− further revealed that these pores have a high adsorption selectivity towards molecules with different sizes, polarities, or π‐conjugated structures.
Radical 4‐exoCyclizations via Template Catalysis
Authors: Gansäuer Andreas , Knebel Karsten , Kube Christian , van Gastel Maurice , Cangönül Asli , Daasbjerg Kim , Hangele Tim , Hülsen Michael , Dolg Michael , Friedrich Joachim 
Published: January 2012

AbstractThe mechanism of catalytic 4‐exocyclizations withoutgem‐dialkyl substitution was investigated by a comparison of cyclic voltammetry, EPR, and computational studies with previously published synthetic results. The most active catalyst is a super‐unsaturated 13‐electron titanocene(III) complex that is formed by supramolecular activation through hydrogen bonding. The template catalyst binds radicals via a two‐point binding that is mandatory for the success of the 4‐exocyclization. The computational investigations revealed that formation of the observedtrans‐cyclobutane product is not possible from the most stable substrate radical. Instead, the most stable product is formed with the lowest energy of activation from a disfavored substrate in a Curtin–Hammett related scenario.
Iterative Sinc−convolution method for solving planar D‐bar equation with application to EIT
Authors: Abbasi Mahdi , Naghsh‐Nilchi Ahmad‐Reza 
Published: January 2012

SUMMARYThe numerical solution of D‐bar integral equations is the key in inverse scattering solution of many complex problems in science and engineering including conductivity imaging. Recently, a couple of methodologies were considered for the numerical solution of D‐bar integral equation, namely product integrals and multigrid. The first one involves high computational complexity and other one has low convergence rate disadvantages. In this paper, a new and efficient sinc‐convolution algorithm is introduced to solve the two‐dimensional D‐bar integral equation to overcome both of these disadvantages and to resolve the singularity problem not tackled before effectively. The method of sinc‐convolution is based on using collocation to replace multidimensional convolution‐form integrals‐ including the two‐dimensional D‐bar integral equations ‐ by a system of algebraic equations. Separation of variables in the proposed method allows elimination of the formulation of the huge full matrices and therefore reduces the computational complexity drastically. In addition, the sinc‐convolution method converges exponentially with a convergence rate of . Simulation results on solving a test electrical impedance tomography problem confirm the efficiency of the proposed sinc‐convolution‐based algorithm. Copyright © 2012 John Wiley & Sons, Ltd.
Long‐term strategies for the treatment of Refsum's disease using therapeutic apheresis
Authors: Zolotov D. , Wagner S. , Kalb K. , Bunia J. , Heibges A. , Klingel R. 
Published: January 2012

AbstractRefsum's disease is a rare autosomal recessive disorder of fatty acid metabolism. Poorly metabolized phytanic acid accumulates in fatty tissues, including myelin sheaths and internal organs, leading to retinitis pigmentosa, peripheral polyneuropathy, cerebellar ataxia, and renal, cardiac or liver impairment. Dietary restriction of phytanic acid in some cases is not sufficient to prevent acute attacks and stabilize the progressive course. Phytanic acid bound to large low density lipoproteins (LDL) and very low density lipoproteins (VLDL) molecules offers the possibility of extracorporeal elimination by lipid apheresis. We report on the long‐term lipid apheresis treatment of four patients with severe Refsum's disease. Retinitis pigmentosa, peripheral polyneuropathy, cerebellar ataxia, anosmia, and sensorineural hearing loss were major symptoms exhibiting a progressive course. Lipid apheresis was performed for 5–13 years without severe complications. Maximum levels of phytanic acid before commencing chronic lipid apheresis were >300 mg/l. During steady state with lipid apheresis, mean phytanic acid before treatments was 87 mg/l and was reduced to 36 mg/l. Mean reduction rate was 59% per treatment. In all patients, abnormal motor nerve conduction velocity with signs of chronic denervation improved, morphological and functional stabilization of eye involvement was observed. Lipid apheresis prevented the extension of the disease to previously unaffected organs in three patients. Extracorporeal elimination of lipoprotein‐phytanic acid complexes by lipid apheresis represents a pathophysiologically guided therapeutic approach, resulting in long‐term improvement or stabilization of overall rehabilitation in patients with progressive Refsum's disease. J. Clin. Apheresis, 2012. © 2012 Wiley Periodicals, Inc.
Chimeric antigen receptors for T cell immunotherapy: current understanding and future directions
Authors: Curran Kevin J. , Pegram Hollie J. , Brentjens Renier J. 
Published: January 2012

AbstractBackgroundThe genetic engineering of T cells through the introduction of a chimeric antigen receptor (CAR) allows for generation of tumor‐targeted T cells. Once expressed by T cells, CARs combine antigen‐specificity with T cell activation in a single fusion molecule. Most CARs are comprised of an antigen‐binding domain, an extracellular spacer/hinge region, a trans‐membrane domain and an intracellular signaling domain resulting in T cell activation after antigen binding.MethodsWe performed a search of the literature regarding tumor immunotherapy using CAR‐modified T cells to provide a concise review of this topic.ResultsThis review aims to focus on the elements of CAR design required for successful application of this technology in cancer immunotherapy. Most notably, proper target antigen selection, co‐stimulatory signaling, and the ability of CAR‐modified T cells to traffic, persist and retain function after adoptive transfer are required for optimal tumor eradication. Furthermore, recent clinical trials have demonstrated tumor burden and chemotherapy conditioning before adoptive transfer as being critically important for this therapy. Future research into counteracting the suppressive tumor microenvironment and the ability to activate an endogenous anti‐tumor response by CAR‐modified T cells may enhance the therapeutic potential of this treatment.ConclusionsIn conclusion, CAR‐modified T cell therapy is a highly promising treatment for cancer, having already demonstrated both promising preclinical and clinical results. However, further modification and additional clinical trials will need to be conducted to ultimately optimize the anti‐tumor efficacy of this approach. Copyright © 2012 John Wiley & Sons, Ltd.
Meteorological environments associated with medicane development
Authors: Tous M. , Romero R. 
Published: January 2012

AbstractMedicanes are ‘Mediterranean tropical‐like cyclones’, warm‐core cyclones that occasionally put in danger the islands and coastal regions. In spite of large geographical differences between the Mediterranean Sea and the tropical oceans, their genesis mechanisms, based on the thermodynamical disequilibrium between the sea and the atmosphere, are similar.The special characteristics of the medicanes make their detection difficult: only with high resolution meteorological analysis data and dense maritime observations that task would be possible. An alternative method, using satellite data and restricted criteria about the disturbance symmetry, size and lifespan, has been successfully used to detect 12 medicanes from 1982 to 2003.To enhance the medicane prediction capability or even to assess the risk potential in future climates, it is necessary to characterize the special conditions of the synoptic‐scale meteorological environments that are needed for their development and maintenance. By comparing these environments against the bulk of Mediterranean cyclonic situations, high values of mid‐tropospheric relative humidity, significant diabatic contribution to the surface level equivalent potential temperature, and low values of tropospheric wind shear, are revealed as important parameters involved in medicane genesis, as in tropical cyclones. An empirical genesis index previously derived for the tropical cyclones is also tested in the study, and its behaviour is revealed as a possible discriminative parameter of the precursor environments.In the context of the growing concern about how climate change will affect the number and intensity of hurricanes, a preliminary analysis for medicanes has been done here. By projecting the previous empirical index into three different global climate model (GCM)‐simulated climates, spatial distributions of the monthly index values have been evaluated. The monthly mean values and the frequency of extreme values of this index tend to decrease, showing that the number of days with a medicane risk tends to reduce at the end of the 21st century. Copyright © 2012 Royal Meteorological Society
Zingiber officinaleextract exhibits antidiabetic potential via modulating glucose uptake, protein glycation and inhibiting adipocyte differentiation: anin vitrostudy
Authors: Rani M Priya , Krishna Mahesh S , Padmakumari Keezheveettil P , Raghu K Gopal , Sundaresan Andikannu 
Published: January 2012

AbstractBACKGROUND:Ginger, the rhizome ofZingiber officinaleRoscoe (Zingiberaceae), a perennial herbaceous plant is native to Southern Asia. Study was aimed to evaluate antioxidant and antidiabetic potential of ginger extract and its characterization. Possible mode of action to elicit antidiabetic activity was also evaluated.METHODS AND RESULTS:Ethyl acetate extract of ginger (EAG) was evaluated for its antioxidant activity in terms of DPPH radical scavenging potential with an IC50value of 4.59 µg/ml. Antidiabetic activity of EAG was evaluated by estimating antiglycation potential (IC50290.84 µg/ml). HPLC profiling of EAG revealed the presence of phenolic components, gingerol and shoagol as major constituents. After determining sub‐toxic concentration of EAG (50 µg/ml), efficacy of extract to enhance glucose uptake in cell lines were checked in L6 mouse myoblast and myotubes. EAG was effective at 5 µg/ml concentration in both cases. Antibody based studies in treated cells revealed the effect of EAG in expressing Glut 4 in cell surface membrane compared to control.CONCLUSION:The antidiabetic effect of ginger was experimentally proved in the study and has concluded that the activity is initiated by antioxidant, antiglycation and potential to express or transport Glut4 receptors from internal vesicles. Copyright © 2012 Society of Chemical Industry
Intellectual Capital and Business Performance: What Structural Relationships Do They Have in Upper‐Upscale Hotels?
Authors: Kim Taegoo (Terry) , Kim Woo Gon , Park Simon Si‐Sa , Lee Gyehee , Jee Bonggu 
Published: January 2012

ABSTRACTThe purpose of this study is to investigate the structural relationships among intellectual capital (INCAP) dimensions and business performance (BUPER) in upper‐upscale hotels. This study classified INCAP into three dimensions: human capital (HUCAP), organizational capital (ORCAP) and customer capital (CUCAP). This study applied a structural equation modeling to investigate the proposed model and hypotheses. The results showed that HUCAP affects ORCAP and CUCAP and that ORCAP influences CUCAP. INCAP dimensions, with the exception of HUCAP, directly affect BUPER; however, HUCAP indirectly affects BUPER via ORCAP and CUCAP. This study helps upper‐upscale hotel managers identify relevant INCAP dimensions and their indicators to enhance BUPER. Copyright © 2012 John Wiley & Sons, Ltd.
Influence of UV irradiation in low frictional performance of CNx coatings
Authors: Tokoroyama Takayuki , Kamiya Makoto , Umehara Noritsugu , Wang Chao , Diao Dongfeng 
Published: January 2012

ABSTRACTThe influence of ultraviolet (UV) irradiation on low frictional performance of CNx coatings with 100 nm thickness having nitrogen contents of 9%, 14% and 19% deposited on Si(100) substrate by ion beam mixing was investigated in N2 atmosphere environment. Three UV lights of 254, 312 and 365 nm were used to irradiate the surface of CNx / Si(100) for 60 min. The changes of N / C ratio and atomic binding energy in the coating were analysed using Auger electron spectroscopy and X‐ray photoelectron spectroscopy, respectively. The friction coefficient of Si3N4 ball sliding against CNx was measured by a pin‐on‐disc tribometer, and wear tracks were analysed by the transmission electron microscope image. The results showed that UV irradiation on CNx coating can decrease the critical frictional cycles for low friction coefficient and that the mechanism is due to the formation of graphite‐like structure in the topmost CNx coating. Copyright © 2012 John Wiley & Sons, Ltd.
Effect of molybdenum and chromium contents on sliding wear of high‐chromium white cast iron at high temperature
Authors: Pinho Karin Faria , Boher Christine , Scandian Cherlio 
Published: January 2012

ABSTRACTHigh‐chromium white cast irons are commonly used in applications requiring excellent abrasion resistance, as in the mining and mineral ore processing industry. Their excellent abrasion resistance is mainly due to their solidification microstructures. In this study, 15 experimental high‐chromium white cast alloys containing different chromium and molybdenum contents and a ratio Cr/C of 10 are examined. The wear experiments were carried out on a pin‐on‐disc tribometer at 700°C. Microstructure has the most important role in dictating friction. It was observed that the wear loss was insignificant compared with that obtained at room temperature. The mean friction coefficient was also lower than that observed at room temperature sliding wear. Copyright © 2012 John Wiley & Sons, Ltd.
Laser doppler perfusion imaging of skin territory to reflect autonomic functional recovery following sciatic nerve autografting repair in rats
Authors: Hu Wen , Yang Min , Chang Jingjian , Shen Zhongyi , Gu Tianwen , Deng Aidong , Gu Xiaosong 
Published: January 2012

AbstractPeripheral nerve repair requires comprehensive evaluation of functional outcomes of nerve regeneration; however, autonomic nerve function is seldom evaluated probably due to lack of suitable quantitative methods. This study sought to determine whether autonomic functional recovery could be reflected by cold‐induced vasodilation (CIVD) within target skin territory, as monitored by laser Doppler perfusion imaging (LDPI). Rats with sciatic nerve defect injury received autologous nerve grafting, and the plantar surface of the hind feet was subjected to LDPI analysis following nerve repair. The results indicated that at 3 and 6 months after autologous nerve grafting, the plantar surface of the hind foot exhibited the same level of CIVD as contralateral normal side, whereas rats in nerve defect group (negative control) showed significantly reduced CIVD. In addition, suitable nerve regeneration and functional recovery were achieved as assessed by pain sensation tests as well as electrophysiological and immunohistological examinations. Based on the potential influence of local autonomic nerve signals on CIVD, it was possible to evaluate functional recovery of autonomic nerves by using LDPI measurements of dermal CIVD. © 2012 Wiley Periodicals, Inc. Microsurgery, 2012.
Lymphaticovenular anastomoses for lymphedema treatment: 18 months postoperative outcomes
Authors: Auba Cristina , Marre Diego , Rodríguez‐Losada Gonzalo , Hontanilla Bernardo 
Published: January 2012

AbstractThe purpose of this work was to report our initial experience with lymphaticovenular anastomoses (LVA), a controversial technique for lymphedema treatment. Although LVA technique was described many years ago, the procedure is not as widespread as it was supposed to be, taking into account the high impact that lymphedema has in the quality of life of patients. Thus, 12 patients, 5 with lower limb and 7 with upper limb lymphedema, underwent LVA surgery under local anesthesia. Two patients were excluded from the study due to the lack of follow‐up. At 18 months, 8 out 10 patients showed a variable objective reduction of the perimeter of the limbs and 9 patients presented a subjective clinical improvement. These results joined to the outcomes of the most experienced surgeons in this field are encouraging, although there are still many issues that need to be addressed with research to optimize the efficacy of this technique. © 2012 Wiley Periodicals, Inc. Microsurgery, 2012.
Formation of resonance states due to interaction between resonators in arrays used in dielectric metamaterials
Authors: Chen Fang , Wang Xiaohui , Semouchkina Elena 
Published: January 2012

AbstractElectromagnetic responses of 1D dielectric resonator arrays variously positioned with respect to the incident wave are investigated in standard waveguides and free space. It is demonstrated that interaction between resonators causes splitting of the array resonance with the formation of several states that exhibit different capabilities for supporting wave transfer. © 2012 Wiley Periodicals, Inc. Microwave Opt Technol Lett 54:555–560, 2012; View this article online at wileyonlinelibrary.com. DOI 10.1002/mop.26596
Widely tunable multiwavelength Brillouin–erbium fiber laser by eliminating self‐lasing cavity modes
Authors: Zhao Junfa , Yang Xiufeng , Zhang Cheng , Tong Zhengrong 
Published: January 2012

AbstractA linear multiwavelength Brillouin/erbium fiber laser (MWBEFL) with 40 nm tuning range is presented.The characteristic of opposite transmission of Brillouin Stokes (BS) signals in stimulated Brillouin scattering is used as reflector in one end of the fiber laser. The influence of the self‐lasing modes existing in conventional MWBEFLs is eliminated, because there is no physical mirror at one end of the linear cavity. The threshold power is reduced, and the generation of BS signals is enhanced owing to the double‐pass preamplification for the Brillouin pump by the erbium‐doped fiber amplifier before entering the single‐mode fiber. © 2012 Wiley Periodicals, Inc. Microwave Opt Technol Lett 54:612–614, 2012; View this article online at wileyonlinelibrary.com. DOI 10.1002/mop.26604
A silicon quasi‐DOS based on reverse‐biased pn diode
Authors: Zhao Yong , Shao Haifeng , Hu Ting , Yu Ping , Yang Jianyi , Wang Minghua , Jiang Xiaoqing 
Published: January 2012

AbstractAn interference‐type silicon waveguide device, which uses the particularity of the overlap between the optical field and the depletion layer in the reverse‐biased pn diode, has presented a “digital” response characteristic. Using this characteristic, a quasi‐digital optical switch is proposed and discussed. © 2012 Wiley Periodicals, Inc. Microwave Opt Technol Lett 54:635–638, 2012; View this article online at wileyonlinelibrary.com. DOI 10.1002/mop.26618
A 0.18‐μm SiGe BiCMOS HBT VCO using diode degeneration
Authors: Jang Sheng‐Lyang , Hsieh Chao‐Wei , Chang Chia‐Wei , Hsue Ching‐Wen 
Published: January 2012

AbstractThis letter proposes a BiCMOS voltage‐controlled oscillator (VCO), which was implemented in the standard TSMC 0.18 μm SiGe 3P6M BiCMOS process. The VCO consists of an nMOSFET cross‐coupled oscillator stacked in series with source degenerated HBT diodes. SiGe HBT has an inherently low flicker noise compared to CMOS devices. At the supply voltage of 1.5 V, the output phase noise of the VCO is −122.01 dBc/Hz at 1 MHz offset frequency from the carrier frequency of 5.6 GHz, and the figure of merit is −190.43 dBc/Hz. © 2012 Wiley Periodicals, Inc. Microwave Opt Technol Lett 54:605–608, 2012; View this article online at wileyonlinelibrary.com. DOI 10.1002/mop.26619