bluuebunny/crossref_metadata_2025_split huggingface dataset:
Intermolecular Clamping by Hydrogen Bonds: 2‐Pyridone⋅NH3
Authors: Blaser Susan , Ottiger Philipp , Lobsiger Simon , Frey Hans‐Martin , Leutwyler Samuel 
Published: May 2011

AbstractA combined spectroscopic and ab initio theoretical study of the doubly hydrogen‐bonded complex of 2‐pyridone (2PY) with NH3has been performed. The S1←S0spectrum extends up to ≈1200 cm−1above the 000band, close to twice the range observed for 2PY. The S1state nonradiative decay for vibrations above ≈300 cm−1in the NH3complex is dramatically slowed down relative to bare 2PY. Also, the Δv=2, 4,… overtone bands of the ν1′ and ν2′ out‐of‐plane vibrations that dominate the low‐energy spectral region of 2PY are much weaker or missing for 2PY⋅NH3, which implies that the bridging (2PY)NH⋅⋅⋅NH3and H2NH⋅⋅⋅OC H‐bonds clamp the 2PY at a planar geometry in the S1state. The mass‐resolved UV vibronic spectra of jet‐cooled 2PY⋅NH3and its H/D mixed isotopomers are measured using two‐color resonant two‐photon ionization spectroscopy. The S0and S1equilibrium structures and normal‐mode frequencies are calculated by density functional (B3LYP) and correlated ab initio methods (MP2 and approximate second‐order coupled‐cluster, CC2). The S1←S0vibronic assignments are based on configuration interaction singles (CIS) and CC2 calculations. A doubly H‐bonded bridged structure ofCSsymmetry is predicted, in agreement with that of Held and Pratt [J. Am. Chem. Soc.1993,115, 9718]. While the B3LYP and MP2 calculated rotational constants are in very good agreement with experiment, the calculated H2NH⋅⋅⋅OC H‐bond distance is ≈0.7 Å shorter than that derived by Held and Pratt. On the other hand, this underlines their observation that ammonia can act as a strong H‐bond donor when built into an H‐bonded bridge. The CC2 calculations predict the H2NH⋅⋅⋅O distance to increase by 0.2 Å upon S1←S0electronic excitation, while the (2PY)NH⋅⋅⋅NH3H‐bond remains nearly unchanged. Thus, the expansion of the doubly H‐bonded bridge in the excited state is asymmetric and almost wholly due to the weakening of the interaction of ammonia with the keto acceptor group.
TPD‐MS and IR Studies of Cr(acac)3 Binding Upon CVD at Silica and Alumina Surfaces
Authors: Davydenko Lyudmyla , Mischanchuk Boris , Pokrovskiy Valery , Babich Igor , Plyuto Yuri 
Published: May 2011

AbstractThe mechanism of CVD of Cr(acac)3 molecules at active sites on the surface of silica and alumina supports is studied by infrared (IR) spectroscopy and temperature programmed desorption mass spectrometry (TPD‐MS). TPD‐MS patterns of the molecular acetylacetone [H3CCOCH2COCH3]+• (m/z 100), as well as the fragment ions [H3CCOCH2CO]+ (m/z 85) and [H3CCO]+ (m/z 43), are monitored to study the interaction of acetylacetonate ligands with the support surface upon thermal treatment.It is found that surface hydroxyl groups are responsible for the binding of Cr(acac)3 molecules, only in the case of the silica support, due to hydrogen bonding (H‐bonding) with the acetylacetonate ligand. The TPD‐MS of Cr(acac)3/SiO2 exhibits the pattern of the molecular ion (m/z 100) in the range 400 − 600 K, which means the release of Hacac molecules, originating from Cr(acac)3 molecules, H‐bonded to surface hydroxyl groups. In contrast, the binding of Cr(acac)3 molecules at the alumina surface is due to electron donor‐acceptor interaction of acetylacetonate ligands with Al3+ sites. The TPD‐MS of Cr(acac)3/Al2O3 exhibits mainly the fragment ion [H3CCO]+ (m/z 43) within the range 400 − 750 K, and only negligible intensity of the molecular ion (m/z 100) in the range 400 − 600 K.
Data fusion‐based interference matrix generation for cellular system frequency planning
Authors: Wu Zhouyun , Huang Aiping , Zhou Haojie , Hua Cunqing , Qian Jun 
Published: May 2011

AbstractInterference matrix (IM) has been widely used in frequency planning/optimization of cellular systems because it describes the interaction between any two cells. IM is generated from the source data gathered from the cellular system, either mobile measurement reports (MMRs) or drive test (DT) records. IM accuracy is not satisfactory since neither MMRs nor DT records contain complete information on interference and traffic distribution. In this paper, two IM generation algorithms based on source data fusion are proposed. Data fusion in one algorithm is to reinforce MMRs data, using the frequency‐domain information of DT data from the same region. Data fusion in the other algorithm is to reshape DT data, using the traffic distribution information extracted from MMRs from the same region. The fused data contain more complete information so that more accurate IM can be obtained. Simulation results have validated this conclusion. Copyright © 2011 John Wiley & Sons, Ltd.
GPM: A generic and scalable P2P model that optimizes tree depth for multicast communications
Authors: Amad Mourad , Meddahi Ahmed , Aïssani Djamil , Vanwormhoudt Gilles 
Published: May 2011

SUMMARYGroup communications (real‐time and non‐real‐time) refer to one‐to‐many or many‐to‐many communications. On the one hand, multicast is considered as an appropriate solution for supporting group communication‐oriented applications (we distinguish IP network multicast from application layer multicast). On the other hand, peer‐to‐peer model tends to be a good candidate for supporting today Internet applications (e.g. P2P IPTV, P2P VoIP, etc.). In this context, P2P has attracted significant interest in the recent years. This is mainly due to its properties that also make P2P well adapted to today social networks. In this paper, we propose GPM (Generic P2P Multicast): a novel generic and scalable approach, that optimizes multicast tree depth in P2P networks (structured and unstructured), and contributes to control the network overlay latency. For multicast tree construction, the approach we propose is based on a distributed algorithm using a specific data structures (adjacency and forwarding matrixes). GPM model inherits from P2P attributes such as scalability, flexibility and fault tolerance, while taking into consideration the respective characteristics of one‐to‐many and many‐to‐many type of applications. We also give a performance evaluation for validation and comparison purposes while considering some main existing application layer multicast protocols. Copyright © 2011 John Wiley & Sons, Ltd.
DNA fusion gene vaccines induce cytotoxic T‐cell attack on naturally processed peptides of human prostate‐specific membrane antigen
Authors: Vittes Gisella E. , Harden Elena L. , Ottensmeier Christian H. , Rice Jason , Stevenson Freda K. 
Published: May 2011

AbstractFor long‐term attack on tumor cells in patients with prostate cancer, induction of cytolytic T cells is desirable. Several lineage‐specific target proteins are known and algorithms have identified candidate MHC class I‐binding peptides, particularly for HLA‐A*0201. We have designed tolerance‐breaking DNA fusion vaccines incorporating a domain of tetanus toxin fused to candidate tumor‐derived peptide sequences. Using three separate peptide sequences from prostate‐specific membrane antigen (PSMA) (peptides PSMA27, PSMA663, and PSMA711), this vaccine design induced high levels of CD8+ T cells against each peptide in a HLA‐A*0201 preclinical model. In contrast, the full‐length PSMA sequence containing all three epitopes was poorly immunogenic. Induced T cells were cytotoxic against peptide‐loaded tumor cells, but only those against PSMA27 or PSMA663 peptides, and not PSMA711, were able to kill tumor cells expressing endogenous PSMA. Cytotoxicity was also evident in vivo. The preclinical model provides a powerful tool for generating CD8+ T cells able to predict whether target cells can process and present peptides, essential for planning peptide vaccine‐based clinical trials.
Susceptibility loci for the defective foreign protein‐induced tolerance in New Zealand Black mice: Implication of epistatic effects of Fcgr2b and Slam family genes
Authors: Fujii Takuma , Hou Rong , Sato‐Hayashizaki Aya , Obata Masaomi , Ohtsuji Mareki , Ikeda Kenichi , Mitsui Kenichi , Kodera Yo , Shirai Toshikazu , Hirose Sachiko , Nishimura Hiroyuki 
Published: May 2011

AbstractIn contrast to normal mice, autoimmune‐prone New Zealand Black (NZB) mice are defective in susceptibility to tolerance induced by deaggregated bovine γ globulin (DBGG). To examine whether this defect is related to the loss of self‐tolerance in autoimmunity, susceptibility loci for this defect were examined by genome‐wide analysis using the F2 intercross of nonautoimmune C57BL/6 (B6) and NZB mice. One NZB locus on the telomeric chromosome 1, designated Dit (Defective immune tolerance)‐1, showed a highly significant linkage. This locus overlapped with a locus containing susceptibility genes for autoimmune disease, namely Fcgr2b and Slam family genes. To investigate the involvement of these genes in the defective tolerance to DBGG, we took advantage of two lines of Fcgr2b‐deficient B6 congenic mice: one carries autoimmune‐type, and the other carries B6‐type, Slam family genes. Defective tolerance was observed only in Fcgr2b‐deficient mice with autoimmune‐type Slam family genes, indicating that epistatic effects of both genes are involved. Thus, common genetic mechanisms may underlie the defect in foreign protein antigen‐induced tolerance and the loss of self‐tolerance in NZB mouse‐related autoimmune diseases.
Electrochemical Properties of a Conducting Film Derived from Iron(II) Tris(diaminopolypyridyl) Complex in the S(IV) Oxoanions Reduction
Authors: García Camilo , Domínguez Cristian , Aliaga Alvaro , Matsuhiro Betty , Mendoza Leonora , Aguirre María J. , Isaacs Mauricio 
Published: May 2011

AbstractA new conducting film derived from the complex [Fe (diaphen)3]2+, (diaphen=5,6‐diamino‐1,10‐phenanthroline) was electropolymerized by cyclic voltammetry onto a glassy carbon electrode. Poly‐[FeII (diaphen)3] was studied by cyclic voltammetry, SEM, UV‐vis and micro‐Raman spectroscopy. Poly‐[FeII (diaphen)3] shows electrocatalytic activity in HSO3− reduction in an ethanol/water solution. Electrocatalysis is centered at the π ring of phenanthroline. Rotating disk electrode studies showed a 0.117 V/dec Tafel slope, suggesting an EC process where the electrochemical process is the determining step. The chemical step was studied by UV‐vis spectroelectrochemistry. Amperometric behavior showed a linear range between 47.5 µM to 417 µM and the LOD was 19.5 µM.
Oxidation of Sanguinarine and Its Dihydro‐Derivative at a Pyrolytic Graphite Electrode Using Ex Situ Voltammetry. Study of the Interactions of the Alkaloids with DNA
Authors: Vacek Jan , Vrublová Eva , Kubala Martin , Janovská Marika , Fojta Miroslav , Šimková Eva , Stýskala Jakub , Skopalová Jana , Hrbáč Jan , Ulrichová Jitka 
Published: May 2011

AbstractThis study describes the oxidation of sanguinarine (SG) and its metabolite dihydrosanguinarine (DHSG) on the surface of a basal‐plane pyrolytic graphite electrode (PGE). Since both alkaloids strongly adsorb onto the surface of pyrolytic graphite, measurements were performed using ex situ voltammetric methods, adsorptive transfer (AdT) cyclic voltammetry (CV) and square‐wave voltammetry (SWV). Oxidation peaks of SG (peak A) and DHSG (peak A*) were observed around the potential of +0.7 V (vs. Ag/AgCl/3 M KCl), depending on the experimental conditions. The voltammetric peaks A and A* are probably related to the oxidation of N‐methylphenanthridine nitrogenous heterocycle of SG and oxidation of DHSG back to SG, respectively. The electrochemical results and optimized AdT SWV were subsequently applied to the study of the interactions of SG and DHSG with DNA in vitro. Analysis of the alkaloid/DNA interactions was based on observing heights of oxidation peaks A and A* after incubation of SG and/or DHSG with supercoiled (sc) DNA [pBSK(−)]. Electrochemical study of the interactions was supported and complemented with measurements using gel electrophoresis (Topoisomerase I scDNA relaxation assay) and steady‐state and time‐resolved fluorescence spectroscopy. The results suggest that SG intercalates into the double‐stranded structure of scDNA (the SG/base pair ratio is max. 1/4) while increased binding affinity was observed for quaternary cation (SG+). DHSG which, unlike SG+, does not possess a strictly planar molecular structure, did not show intercalative DNA binding in any of the three methods applied.
Confirmation analysis of ethyl glucuronide and ethyl sulfate in human serum and urine by CZE‐ESI‐MSn after intake of alcoholic beverages
Authors: Caslavska Jitka , Jung Balthasar , Thormann Wolfgang 
Published: May 2011

AbstractCZE coupled to sheath liquid‐based electrospray ionization (ESI) and multiple‐stage ion trap mass spectrometry (MSn) was used for the confirmation analysis of ethyl glucuronide (EtG) and ethyl sulfate (EtS) in human serum and urine collected after intake of alcoholic beverages. Electrophoretic separations were performed in uncoated fused‐silica capillaries using a pH 9.5 ammonium acetate background electrolyte and normal polarity. MS detection of EtG and EtS occurred after negative ionization using a spray liquid containing 0.5% v/v ammonia in isopropanol/water (60:40%, v/v). CZE‐MS and CZE‐MS2 results obtained after injection of solid‐phase extracts for EtG and EtS and of diluted urine confirmed the presence of EtG and EtS in samples whose levels were previously determined by CZE with indirect UV detection. Detection limits of each compound were estimated to be around 2.0 (injection of diluted urine) and 0.2 μg/mL (extracts).
Impact of light quality and quantity on growth rate kinetics of Selenastrum capricornutum
Authors: Gutierrez‐Wing Maria T. , Benson Barbara C. , Rusch Kelly A. 
Published: May 2011

AbstractMicroalgal biomass produced in indoor photobioreactors can be used as inoculum for large‐scale outdoor cultures or directly for the production of high‐value bioproducts due to the higher control of these cultures compared with outdoor systems. One of the main costs of indoor microalgal cultures is the illumination. This work can be used as a basis for the optimization of the light source for indoor microalgal biomass production, based on the light source type, irradiance, productivity, growth rate, attenuation coefficients, and contaminant growth on the reactor's side‐walls. Four commercially available near 400‐W artificial light sources for microalgal cultures (metal halide (MH), high‐pressure sodium (HPS), Son Agro®, and fluorescent) were compared. The light elevation and the surface scalar irradiance were shown to have a linear relationship. The attenuation coefficient in air (ka) was highest with Son Agro®. A linear partition of the attenuation coefficient between the water and biomass and an exponential relationship between average scalar irradiance and depth were found. An empirical overall scalar attenuation coefficient for each light source was obtained. The lowest maximum observed growth rate was obtained with fluorescent light (0.98 d−1) and the highest with Son Agro® (2.39 d−1). The highest growth on the reactor's wall was obtained with Son Agro®. Further studies resulted in a higher maximum specific growth rate and optimum irradiance for HPS (2.37 d−1 and 460 μmol s−1 m−2) compared with those observed with MH (1.73 d−1 and 391 μmol s−1 m−2).
Shaking table testing and numerical simulation of the seismic response of a typical Mexican colonial temple
Authors: Chávez Marcos , Meli Roberto 
Published: May 2011

SUMMARYA shaking table testing program was undertaken with the main objective of providing basic information for the calibration of analytical models, and procedures for determining seismic response of typical stone masonry temples of the 16–18th centuries stone masonry construction in Mexico. A typical colonial temple was chosen as a prototype. A model at a 1:8 geometric scale was built with the same materials and techniques as the prototype, and was subjected to horizontal and vertical motions of increasing intensities. The maximum applied intensity corresponded to a base shear force of about 58 of the total building weight. Vertical component of the base motion significantly affected the response and increased the damage of the model. Damage patterns were similar to those observed in actual temples. Damping coefficients of the response ranged from 7 for undamaged state, reached about 14 for severe damage.The main features of the measured response were compared with those computed using a nonlinear, finite element model; for the latter, a constitutive law developed for plain concrete was adopted for reproducing cracking and crushing of the irregular stone masonry. Observed damage patterns as well as measured response could be reproduced with reasonable accuracy by the analytical simulation, except for some local vibrations, as those at the top of the bell towers. It can be concluded that the simple constitutive law adopted for the simulation was able to reproduce the experimental response with reasonable level of accuracy. Copyright © 2011 John Wiley & Sons, Ltd.
Tiny Helpers Fight the Spill
Authors: Boetius Antje 
Published: May 2011

AbstractThe well in the Gulf of Mexico has been sealed, but the consequences of the ecological catastrophe remain unknown. Contributing to the degradation of the massive contamination are microorganisms that literally devour the oil in the water and on the ocean floor. Marine researchers have been investigating the hungry bacteria for many yearsMicrobiological background information (author: Prof. Friedrich Widdel) and additional links:http://www.mpi‐bremen.de/Abbau_von_Erdl_durch_Bakterien_‐_Grundlegende_Gesichtspunkte_aus_mikrobiologischer_Sicht.html
New Tools for Ancient Ruins
Authors: Drewello Rainer , Freitag Burkhard , Schlieder Christoph 
Published: May 2011

AbstractArchitectural monuments are perpetual construction sites, and historical plans, drafts and photographs are essential for their restoration. Yet the archives of many churches, castles and palaces are either in poor condition or difficult to access. Cultural researchers and engineering scientists are now adding these sources to a database system in order to increase their usabilityhttp://www.monarch‐project.euhttp://www.uni‐bamberg.de/buchara‐projekt
Studies on hypervalent compounds and synthetic work using heteroaromatic cations
Authors: Akiba Kin‐ya 
Published: May 2011

AbstractThe major studies of my research group in the University of Tokyo (1965–1980) and Hiroshima University (1980–2000) and some related research (2000–2010) are outlined briefly. The following themes are included mostly in chronological order: (1) phosphoranes and nitrosoimines, (2) synthetic work based on heteroaromatic cations and activation of imines, (3) bond switching at hypervalent sulfurane (10‐S‐3): energy of a hypervalent bond, (4) formation of the hypervalent bond, (5) edge inversion of antimony(III) and bismuth(III) compounds, (6) apicophilicity, pseudorotation, and ligand coupling, (7) freezing pseudorotation of phosphoranes and its effect, (8) hypervalent ate complexes of antimony and bismuth and their transition metal complexes, (9) hypervalent organotellurium compounds, (10) porphyrins of group 15 elements (phosphorus, arsenic, and antimony), and (11) synthesis and structure of hypervalent carbon species (10‐C‐5 and 12‐C‐6). © 2011 Wiley Periodicals, Inc. Heteroatom Chem 22:207–274, 2011; View this article online at wileyonlinelibrary.com. DOI 10.1002/hc.20726
Prevalence and incidence of acute and chronic comorbidity in patients with squamous cell carcinoma of the head and neck
Authors: Landis Sarah H. , El‐Hariry Iman A. , van Herk‐Sukel Myrthe P. P. , van den Haak Pieter , Janssen‐Heijnen Maryska L. G. , Penning‐van Beest Fernie J. A. , Herings Ron M. C. 
Published: May 2011

AbstractBackgroundLimited data exist on the burden of comorbidity among patients with squamous cell head and neck cancer (SCCHN) before and during cancer treatment.MethodsThe precancer prevalence and incidence rates of 8 comorbid conditions were estimated among a population‐based cohort of 1499 patients with SCCHN in the Netherlands. Patients with cancer, treatments, and comorbidities were identified in the PHARMO Record Linkage System (RLS) using hospital admissions and/or dispensing codes. Prevalence proportions and incidence rates were also compared against a matched cancer‐free population.ResultsCardiovascular (41%) and respiratory diseases (12%) were the most prevalent comorbidities. Incidence rates of most comorbidities were highest the first 6 months after cancer diagnosis and decreased over time. Patients receiving chemotherapy‐based treatment had significantly higher incidence rates of anemia and other malignant diseases.ConclusionsHigh rates of acute and chronic comorbidity were observed; knowledge of comorbidity burden aids in establishing a benefit–risk profile for investigational SCCHN therapies. © 2011 Wiley Periodicals, Inc. Head Neck, 2012
Investigating the spatial distribution of water levels in the Mackenzie Delta using airborne LiDAR
Authors: Hopkinson C. , Crasto N. , Marsh P. , Forbes D. , Lesack L. 
Published: May 2011

AbstractAirborne light detection and ranging (LiDAR) data were used to map water level (WL) and hydraulic gradients (δH/δx) in the Mackenzie Delta. The LiDAR WL data were validated against eight independent hydrometric gauge measurements and demonstrated mean offsets from − 0·22 to + 0·04 m (σ< 0·11). LiDAR‐based WL gradients could be estimated with confidence over channel lengths exceeding 5–10 km where the WL change exceeded local noise levels in the LiDAR data. For the entire Delta, the LiDAR sample coverage indicated a rate of change in longitudinal gradient (δ2H/δx) of 5·5 × 10−10 m m−2; therefore offering a potential means to estimate average flood stage hydraulic gradient for areas of the Delta not sampled or monitored. In the Outer Delta, within‐channel and terrain gradient measurements all returned a consistent estimate of − 1 × 10−5 m m−1, suggesting that this is a typical hydraulic gradient for the downstream end of the Delta. For short reaches (<10 km) of the Peel and Middle Channels in the middle of the Delta, significant and consistent hydraulic gradient estimates of − 5 × 10−5 m m−1 were observed. Evidence that hydraulic gradients can vary over short distances, however, was observed in the Peel Channel immediately upstream of Aklavik. A positive elevation anomaly (bulge) of > 0·1 m was observed at a channel constriction entering a meander bend, suggesting a localized modification of the channel hydraulics. Furthermore, water levels in the anabranch channels of the Peel River were almost 1 m higher than in Middle Channel of the Mackenzie River. This suggests: (i) the channels are elevated and have shallower bank heights in this part of the delta, leading to increased cross‐delta and along‐channel hydraulic gradients; and/or (ii) a proportion of the Peel River flow is lost to Middle Channel due to drainage across the delta through anastamosing channels. This study has demonstrated that airborne LiDAR data contain valuable information describing Arctic river delta water surface and hydraulic attributes that would be challenging to acquire by other means. Copyright © 2011 John Wiley & Sons, Ltd.