bluuebunny/crossref_metadata_2025_split huggingface dataset:
Contrasting impacts of spring thermal conditions over Tibetan Plateau on late‐spring to early‐summer precipitation in southeast China
Authors: Liu Xiaodong , Wang Yi 
Published: May 2011

AbstractThe thermal condition of the Tibetan Plateau (TP) is considered as an important factor impacting the Asian monsoon. However, how to determine the thermal condition and when and where the Asian monsoon is influenced are still open issues. Here the spring thermal condition of TP is determined using 600 hPa temperatures. For the past 30 years (1979–2008), we have determined three cold years (CY) and three warm years (WY) and conducted contrasting analyses of the subsequent precipitation and large‐scale atmospheric dynamics over China. Our analyses indicate that the precipitation is more than normal in late spring (LS) and less than normal in early summer (ES) during WY in southeast China (SEC), while the opposite pattern is true during CY. Further analyses of 850 hPa circulation and tropospheric vertical motion show that the anomalous southerly wind and ascending motion are dominated in SEC during LS for WY and ES for CY, while the anomalous westerly wind and descending motion are dominated during ES for WY and LS for CY. The coherent dynamical structure impacts the monsoon moisture transport and large‐scale atmospheric stability, and therefore is the fundamental cause of precipitation anomalies. Copyright © 2011 Royal Meteorological Society
Reverse engineering of protein secretion by uncoupling of cell cycle phases from growth
Authors: Buchetics Markus , Dragosits Martin , Maurer Michael , Rebnegger Corinna , Porro Danilo , Sauer Michael , Gasser Brigitte , Mattanovich Diethard 
Published: May 2011

AbstractThe demand for recombinant proteins both for biopharmaceutical and technical applications is rapidly growing, and therefore the need to establish highly productive expression systems is steadily increasing. Yeasts, such as Pichia pastoris, are among the widely used production platforms with a strong emphasis on secreted proteins. Protein secretion is a limiting factor of productivity. There is strong evidence that secretion is coupled to specific growth rate (µ) in yeast, being higher at higher µ. For maximum productivity and product titer, high specific secretion rates at low µ would be desired. At high secretion rates cultures contain a large fraction of cells in the G2 and M phases of cell cycle. Consequently, the cell design target of a high fraction of cells in G2 + M phase was achieved by constitutive overexpression of the cyclin gene CLB2. Together with predictive process modeling this reverse engineered production strain improved the space time yield (STY) of an antibody Fab fragment by 18% and the product titer by 53%. This concept was verified with another secreted protein, human trypsinogen. Biotechnol. Bioeng. 2011;108: 2403–2412. © 2011 Wiley Periodicals, Inc.
Reduction of acetone to isopropanol using producer gas fermenting microbes
Authors: Ramachandriya Karthikeyan D. , Wilkins Mark R. , Delorme Marthah J.M. , Zhu Xiaoguang , Kundiyana Dimple K. , Atiyeh Hasan K. , Huhnke Raymond L. 
Published: May 2011

AbstractGasification‐fermentation is an emerging technology for the conversion of lignocellulosic materials into biofuels and specialty chemicals. For effective utilization of producer gas by fermenting bacteria, tar compounds produced in the gasification process are often removed by wet scrubbing techniques using acetone. In a preliminary study using biomass generated producer gas scrubbed with acetone, an accumulation of acetone and subsequent isopropanol production was observed. The effect of 2 g/L acetone concentrations in the fermentation media on growth and product distributions was studied with “Clostridium ragsdalei,” also known as Clostridium strain P11 or P11, and Clostridium carboxidivorans P7 or P7. The reduction of acetone to isopropanol was possible with “C. ragsdalei,” but not with P7. In P11 this reaction occurred rapidly when acetone was added in the acidogenic phase, but was 2.5 times slower when added in the solventogenic phase. Acetone at concentrations of 2 g/L did not affect the growth of P7, but ethanol increased by 41% and acetic acid concentrations decreased by 79%. In the fermentations using P11, growth was unaffected and ethanol concentrations increased by 55% when acetone was added in the acidogenic phase. Acetic acid concentrations increased by 19% in both the treatments where acetone was added. Our observations indicate that P11 has a secondary alcohol dehydrogenase that enables it to reduce acetone to isopropanol, while P7 lacks this enzyme. P11 offers an opportunity for biological production of isopropanol from acetone reduction in the presence of gaseous substrates (CO, CO2, and H2). Biotechnol. Bioeng. 2011;108: 2330–2338. © 2011 Wiley Periodicals, Inc.
Transcatheter aortic valve implantation for severe aortic regurgitation in a stentless bioprosthetic valve with the core valve revalving system—Technical tips and role of the accutrak system
Authors: Sarkar Kunal , Ussia Gian Paolo , Tamburino Corrado 
Published: May 2011

AbstractTranscatheter aortic valve implantation may offer a less invasive alternate to surgical reoperation in patients with failed aortic bioprosthetic valves. Prior reports have focussed on successful transcatheter treatment of stented bioprosthesis. Newer stentless valves offer unique technical challenges. In the absence of radiopaque markers, the deployment is carried out under angiographic control. Device stability is also an important issue in cases of severe regurgitation. We report on the first case of percutaneous replacement of a severely regurgitant degenerated stentless bioprosthesis treated with the new iteration of the core valve system incorporating the Accutrak stability layer. Salient technical expedients have been mentioned and discussed in detail. © 2011 Wiley‐Liss, Inc.
Selective Modification of the Acid–Base Properties of Ceria by Supported Au
Authors: C. I. Bezen Manuela , Breitkopf Cornelia , El Kolli Nadia , Krafft Jean‐Marc , Louis Catherine , Lercher Johannes A. 
Published: May 2011

AbstractAu supported on CeO2 prepared by deposition–precipitation with urea leads to a basic catalyst. Au acts in two ways as surface modifier. First, Au selectively interacts with Ce4+ cations by either blocking access to or reducing Ce4+ to Ce3+. Second, the resulting Au atoms (presumably as Au+ ions) act as soft, weak Lewis acid sites stabilizing carbanion intermediates and enhancing hydride abstraction in the dehydrogenation of alcohols. In consequence, the thus‐synthesized basic catalyst catalyzes the dehydrogenation of propan‐2‐ol to acetone with high efficiency and without notable deactivation. Additionally, the dehydration pathway of propan‐2‐ol is eliminated, as Au also quantitatively blocks access to strongly acidic Ce4+ ions or reduces them to Ce3+.
A Foldamer at the Liquid/Graphite Interface: The Effect of Interfacial Interactions, Solvent, Concentration, and Temperature
Authors: Shen Yong‐Tao , Zhu Ningbo , Zhang Xue‐Mei , Deng Ke , Feng Wei , Yan Qifan , Lei Shengbin , Zhao Dahui , Zeng Qing‐Dao , Wang Chen 
Published: May 2011

AbstractThe unfolding process and self‐assembly of a foldable oligomer (foldamer 1) at the liquid/graphite interface were investigated by scanning tunnelling microscopy. At the level of molecular conformation, we identified several molecular conformations (Az, B, C, D, E) that represent intermediate states during unfolding, which may help to elucidate the unfolding process at the liquid/graphite interface. Adsorption at the interface traps the intermediate states of the unfolding process, and STM has proved to be a powerful technique for investigating folding and unfolding of a foldamer at the molecular level, which are not accessible by other methods. The STM observations also revealed that varying the solvent and/or concentration results in different self‐assemblies of foldamer 1 as a result of variations in molecular conformations. The solvent and concentration effects were attributed to the changes in existing states (extended or folded) of foldamers in solution, which in turn affect the distribution of adsorbed molecular conformations at the interface. This mechanism is quite different from other systems in which solvent and concentration effects were also observed.
One‐Dimensional Magnetic Nanowires Obtained by Protein Fibril Biotemplating
Authors: Juárez Josué , Cambón Adriana , Topete Antonio , Taboada Pablo , Mosquera Víctor 
Published: May 2011

AbstractMagnetic nanowires were obtained through the in situ synthesis of magnetic material by Fe‐controlled nanoprecipitation in the presence of two different protein (human serum albumin (HSA) and lysozyme (Lys)) fibrils as biotemplating agents. The structural characteristics of the biotemplates were transferred to the hybrid magnetic wires. They exhibited excellent magnetic properties as a consequence of the 1D assembly and fusion of magnetite nanoparticles as ascertained by SQUID magnetometry. Prompted by these findings, we also checked their potential applicability as MRI contrast agents. The magnetic wires exhibited large r2* relaxivities and sufficient contrast resolution even in the presence of an extremely small amount of Fe in the magnetic hybrids, which would potentially enable their use as T2 contrast imaging agents.
Synthesis, Characterisation and Application of Iridium(III) Photosensitisers for Catalytic Water Reduction
Authors: Gärtner Felix , Cozzula Daniela , Losse Sebastian , Boddien Albert , Anilkumar Gopinatan , Junge Henrik , Schulz Thomas , Marquet Nicolas , Spannenberg Anke , Gladiali Serafino , Beller Matthias 
Published: May 2011

AbstractThe synthesis of novel, monocationic iridium(III) photosensitisers (Ir‐PSs) with the general formula [IrIII(C^N)2(N^N)]+ (C^N: cyclometallating phenylpyridine ligand, N^N: neutral bidentate ligand) is described. The structures obtained were examined by cyclic voltammetry, UV/Vis and photoluminescence spectroscopy and X‐ray analysis. All iridium complexes were tested for their ability as photosensitisers to promote homogeneously catalysed hydrogen generation from water. In the presence of [HNEt3][HFe3(CO)11] as a water‐reduction catalyst (WRC) and triethylamine as a sacrificial reductant (SR), seven of the new iridium complexes showed activity. [Ir(6‐iPr‐bpy)(ppy)2]PF6 (bpy: 2,2′‐bipyridine, ppy: 2‐phenylpyridine) turned out to be the most efficient photosensitiser. This complex was also tested in combination with other WRCs based on rhodium, platinum, cobalt and manganese. In all cases, significant hydrogen evolution took place. Maximum turnover numbers of 4550 for this Ir‐PS and 2770 for the Fe WRC generated in situ from [HNEt3][HFe3(CO)11] and tris[3,5‐bis(trifluoromethyl)phenyl]phosphine was obtained. These are the highest overall efficiencies for any Ir/Fe water‐reduction system reported to date. The incident photon to hydrogen yield reaches 16.4 % with the best system.
Recognition of Oxalate by a Copper(II) Polyaza Macrobicyclic Complex
Authors: Mateus Pedro , Delgado Rita , Brandão Paula , Félix Vítor 
Published: May 2011

AbstractA new polyamine macrobicyclic compound was synthesised through a [1+1] “tripod–tripod coupling” strategy and using a Schiff base condensation reaction, followed by sodium borohydride reduction. The resulting compound is a heteroditopic cage (btpN7) in which one of the head units is appropriate for the coordination of copper(II), whereas the other head is available for additional hydrogen‐bonding and electrostatic interactions with substrates. The acid–base behaviour of the new compound, the stability constants of its complex with the Cu2+ ion and the association constants of the copper(II) cryptate with oxalate (oxa2−), malonate (mal2−), succinate (suc2−), maleate (male2−) and fumarate (fum2−) were determined by potentiometry at 298.2 K in aqueous solution and at an ionic strength of 0.10 mol dm−3 in KNO3. These studies revealed a clear preference of the receptor [CuHhbtpN7H2O](2+h)+ for oxa2− over the other dicarboxylate substrates. This arises from co‐operativity between metal–anion coordination and electrostatic and hydrogen‐bonding interactions, in accordance with the ideal size of this dicarboxylate, which allow it to take full advantage of the potential binding sites of the receptor. A qualitative indicator‐displacement study, in agreement with the potentiometric studies, demonstrated that the copper cryptate receptor can be used as a selective visual sensor for oxalate.
Noninvasive detection of aneuploid cells in laryngeal epithelial precursor lesions
Authors: Shani Tali , Primov‐Fever Adi , Wolf Michael , Shalmon Bruria , Amarglio Ninette , Trakhtenbrot Luba , Hirshberg Abraham 
Published: May 2011

AbstractBACKGROUND:Most cases of laryngeal cancer are preceded by precursor lesions which, if left untreated, can progress toward an invasive cancer. The objective of this study was to investigate the presence of chromosomal numerical aberrations in cells that were collected by noninvasive brush sampling from laryngeal lesions.METHODS:Laryngeal brush samples from 52 patients were analyzed simultaneously for morphology and fluorescence in situ hybridization (FISH) using centromeric probes for chromosome 17, chromosome 8, and a locus‐specific instability (LSI) v‐myc avian myelocytomatosis viral oncogene homolog (myc) proto‐oncogene protein (C‐MYC) probe for the MYC gene. The patients were divided according to histopathologic diagnosis. Group 1 included patients with squamous cell carcinoma, carcinoma in situ, and severe dysplasia; Group 2 included patients with moderate dysplasia, mild dysplasia, and hyperplasia; and Group 3 included patients with benign nondysplastic lesions.RESULTS:The proportion of cells with MYC and chromosome 8 gains demonstrated significant trends toward being the highest in Group 1 and the lowest in Group 3 (P = .001 and P = .003, respectively). No significant trend was observed for chromosome 17. Mann‐Whitney Bonferroni‐corrected analyses revealed that the most significant contribution was the difference between Groups 1 and 3 (P = .0195 for MYC gains and P = .036 for chromosome 8 gains). When using a cutoff point of 4% aneuploid cells (ACs), both MYC and chromosome 8 differed significantly between groups (P = .030 and P = .037, respectively).CONCLUSIONS:The current results suggested that FISH analysis of brush samples obtained noninvasively from suspicious laryngeal lesions can augment the clinical examination in predicting the nature of the lesions and can aid clinicians in monitoring and follow‐up of high‐risk patients. Cancer (Cancer Cytopathol) 2011. © 2011 American Cancer Society.
Equivocal and weakly positive hybrid capture 2 tests in women aged 50 and older
Authors: de Vries Christiaan Erik , Shen Rulong , Stephens Julie , Suarez Adrian A. 
Published: May 2011

AbstractThe performance of the Hybrid Capture 2 (HC2) test for human papilloma virus (HPV) detection depends on the prevalence of infection. However, the current HC2 manufacturer recommended interpretative algorithm is the same for all women. This test, which may be particularly useful in perimenopausal and postmenopausal women given the morphologic complexity of their Pap tests, could be affected by the overall lower prevalence of HPV infection in this age group. We investigated HC2 equivocal and weakly positive HPV tests in women 50 years and older and the detection of high‐grade dysplasia (CIN2+) on their follow‐up specimens. All HC2 test data from 1,067 consecutive specimens and 85 additional specimens from women ≥ 50‐years‐old with equivocal and weakly positive HC2 were analyzed. Follow‐up specimens from women with HC2 tests within these ranges were reviewed. No CIN2+ was found on follow‐up of 49 cases of women ≥ 50 with equivocal or weakly positive HC2 results. The current HC2 algorithm resulted in “positive” reports in 63% of specimens with initial equivocal HC2 due to retests mostly within the equivocal range. These results suggest that women 50 years and older may benefit from higher HC2 thresholds. The test could also be reported as HC2 values (RLU/CO) to be interpreted in view of risk factors. Diagn. Cytopathol. 2012. © 2011 Wiley Periodicals, Inc.
Acute toxicity and withdrawal syndromes related to gamma‐hydroxybutyrate (GHB) and its analogues gamma‐butyrolactone (GBL) and 1,4‐butanediol (1,4‐BD)
Authors: Wood David M. , Brailsford Alan D. , Dargan Paul I. 
Published: May 2011

AbstractGamma‐hydroxybutyrate (GHB) has been used as a recreational drug since the 1990s and over the last few years there has been increasing use of its analogues gamma‐butyrolactone (GBL) and to a lesser extent 1,4‐butanediol (1,4BD). This review will summarize the literature on the pharmacology of these compounds; the patterns and management of acute toxicity associated with their use; and the clinical patterns of presentation and management of chronic dependency associated with GHB and its analogues. Copyright © 2011 John Wiley & Sons, Ltd.
Indian hedgehog positively regulates calvarial ossification and modulates bone morphogenetic protein signaling
Authors: Lenton Kelly , James Aaron W. , Manu Alina , Brugmann Samantha A. , Birker Daniel , Nelson Emily R. , Leucht Philipp , Helms Jill A. , Longaker Michael T. 
Published: May 2011

AbstractMuch is known regarding the role of Indian hedgehog (Ihh) in endochondral ossification, where Ihh regulates multiple steps of chondrocyte differentiation. The Ihh−/− phenotype is most notable for severely foreshortened limbs and a complete absence of mature osteoblasts. A far less explored phenotype in the Ihh−/− mutant is found in the calvaria, where bones form predominately through intramembranous ossification. We investigated the role of Ihh in calvarial bone ossification, finding that proliferation was largely unaffected. Instead, our results indicate that Ihh is a pro‐osteogenic factor that positively regulates intramembranous ossification. We confirmed through histologic and quantitative gene analysis that loss of Ihh results in reduction of cranial bone size and all markers of osteodifferentiation. Moreover, in vitro studies suggest that Ihh loss reduces Bmp expression within the calvaria, an observation that may underlie the Ihh−/− calvarial phenotype. In conjunction with the newly recognized roles of Hedgehog deregulation in craniosynostosis, our study defines Ihh as an important positive regulator of cranial bone ossification. genesis 49:784–796, 2011. © 2011 Wiley‐Liss, Inc.
Metal Ion Coordinating Properties of the Highly Preorganized Tetradentate Ligand 1,10‐Phenanthroline‐2,9‐dicarboxaldehyde‐2,9‐dioxime
Authors: Boone Lindsay L. , Mroz Amy E. , VanDerveer Donald G. , Hancock Robert D. 
Published: May 2011

AbstractUse of UV/Vis spectroscopy to measure protonation and formation constants of PDOX (1,10‐phenanthroline‐2,9‐dicarboxaldehyde‐2,9‐dioxime) is reported. All complexes all show a protonation constant of an oxime that is quite close to pKa1 for the free ligand, that is, for ZnII log K for ZnPDOX + H+ [lrarr2] ZnPDOXH+. This is in agreement with literature crystal structures, which show that, for small metal ions such as ZnII, one oxime group of PDOX is left non‐coordinated. Only for PbII is the protonation constant of the PDOX complex significantly lowered, to a value of 8.2. In order to investigate the high log K1 value for the PbII/PDOX complex, and its relatively low protonation constant, the crystal structure of [Pb(PDOXH2)(DMSO)2Cl(ClO4)] (1) was determined.
Pyridine N‐Oxide Mediated Oxidation of Diarylalkynes with Palladium on Carbon
Authors: Sawama Yoshinari , Takubo Masato , Mori Shigeki , Monguchi Yasunari , Sajiki Hironao 
Published: May 2011

AbstractPyridine N‐oxide works as an effective oxidant of 1,2‐diarylalkynes at 120 °C to form benzil derivatives under Pd/C‐catalyzed solvent‐free conditions, and Pd/C could be reused up to five times after simple filtration.
Cross‐Coupling Reactions of Aryl Halides with Amines, Phenols, and Thiols Catalyzed by an N,N′‐Dioxide–Copper(I) Catalytic System
Authors: Yang Haitao , Xi Chao , Miao Zhiwei , Chen Ruyu 
Published: May 2011

AbstractThe coupling reactions of various N, O, and S nucleophilic reagents with aryl halides have been successfully carried out under mild conditions by using a novel chiral N,N′‐dioxide–copper(I) catalytic system as the catalyst. This versatile and efficient catalyst system has been demonstrated to facilitate the cross‐coupling reactions of aryl halides with amines,phenols, and thiols to afford the corresponding desired products in good to excellent yields.
Evolution of crossmodal reorganization of the voice area in cochlear‐implanted deaf patients
Authors: Rouger Julien , Lagleyre Sébastien , Démonet Jean‐François , Fraysse Bernard , Deguine Olivier , Barone Pascal 
Published: May 2011

AbstractPsychophysical and neuroimaging studies in both animal and human subjects have clearly demonstrated that cortical plasticity following sensory deprivation leads to a brain functional reorganization that favors the spared modalities. In postlingually deaf patients, the use of a cochlear implant (CI) allows a recovery of the auditory function, which will probably counteract the cortical crossmodal reorganization induced by hearing loss. To study the dynamics of such reversed crossmodal plasticity, we designed a longitudinal neuroimaging study involving the follow‐up of 10 postlingually deaf adult CI users engaged in a visual speechreading task. While speechreading activates Broca's area in normally hearing subjects (NHS), the activity level elicited in this region in CI patients is abnormally low and increases progressively with post‐implantation time. Furthermore, speechreading in CI patients induces abnormal crossmodal activations in right anterior regions of the superior temporal cortex normally devoted to processing human voice stimuli (temporal voice‐sensitive areas‐TVA). These abnormal activity levels diminish with post‐implantation time and tend towards the levels observed in NHS. First, our study revealed that the neuroplasticity after cochlear implantation involves not only auditory but also visual and audiovisual speech processing networks. Second, our results suggest that during deafness, the functional links between cortical regions specialized in face and voice processing are reallocated to support speech‐related visual processing through cross‐modal reorganization. Such reorganization allows a more efficient audiovisual integration of speech after cochlear implantation. These compensatory sensory strategies are later completed by the progressive restoration of the visuo‐audio‐motor speech processing loop, including Broca's area. Hum Brain Mapp, 2012. © 2011 Wiley Periodicals, Inc