bluuebunny/crossref_metadata_2025_split huggingface dataset:
Chemical Variability of Copaifera reticulataDucke Oleoresin
Authors: Herrero‐Jáuregui Cristina , Casado Miguel A. , das Graças Bichara Zoghbi Maria , Célia Martins‐da‐Silva Regina 
Published: April 2011

AbstractThe copaiba tree (Copaifera spp.) produces an oleoresin which is highly valued due to its medicinal properties. The chemical composition of C. reticulata oleoresin was characterized, and its variability related to seasonal variation (dry and rainy seasons), to successive extractions, and to several factors associated with tree morphometry, disease, and surrounding vegetation structure was investigated. Oleoresin was collected from 24 C. reticulata individuals between October 2006 and March 2008. For seven individuals, oleoresin was extracted for a second time between three and nine months after the first extraction. For each tree, several morphometric variables, viz., the presence of termites, vines, and holes as well as the soil type and surrounding vegetation structure, were recorded. The chemical composition and concentration of the main volatile compounds were identified by GC/MS. Almost 100% of the constituents were sesquiterpenes, the three main ones being β‐caryophyllene, trans‐α‐bergamotene, and β‐bisabolene. A classification analysis separated the C. reticulata individuals in two main groups and further divided one of the main groups in two subgroups, which were defined by different concentrations of the three main compounds. The results showed high intra‐population variability in the composition and concentration of sesquiterpenes, this being comparable to the interspecific variability. It was not possible to determine a clear influence of environmental, morphometrical, and structural factors on the oleoresin composition, although some compounds varied according to the soil type, the volume of oleoresin extracted, and the crown surface.
Variations between Diploids and Tetraploids of Allium przewalskianum, an Important Vegetable and/or Condiment in the Himalayas
Authors: Yao Buqing , Deng Jianming , Liu Jianquan 
Published: April 2011

AbstractAllium przewalskianum, a wild onion species growing at altitudes ranging from 1800 to 4500 m, has long been commonly used as an important vegetable and/or condiment by Tibetans, Indians, and Nepalese in the highlands of the Himalayas and adjacent regions. This species comprises both diploids and tetraploids. In this study, we examined the nutritional content and biomass accumulation profiles of two cytotypes, collected from 29 sites, with different altitudinal origins but cultivated in a common garden. On an average, this species has superior qualities in the minerals and amino acids compared to other edible congeners. When compared with the diploids, the tetraploids grew faster and accumulated more biomass; in addition, the tetraploids had higher values of moisture and energy, higher contents of cystine and phosphorus, but lower fiber levels. Moreover, the tetraploids from the higher altitudes had greater biomasses than the other tetraploids, in addition to having increased levels of proteins, fats, and the minerals Mg, Fe, Mn, and Cu. These results illustrate the large variations in nutritional efficacy and growth within this single morphological species, and provide critical information for its effective consumption in the future.
Can Pollen Headspace Volatiles and Pollenkitt Lipids Serve as Reliable Chemical Cues for Bee Pollinators?
Authors: Piskorski Rafal , Kroder Stefan , Dorn Silvia 
Published: April 2011

AbstractChemical analysis of putative contact chemical cues for pollinators from pollen of two plant species, Ranunculus bulbosus (Ranunculaceae) and Campanula rapunculoides (Campanulaceae), showed high consistency in the qualitative and quantitative composition of pollenkitt surface lipids in all samples analyzed per species. The pollenkitt lipids of R. bulbosus included an aldehyde, fatty acid amides, saturated and unsaturated hydrocarbons, and secondary alcohols; the lipids of C. rapunculoides consisted of an aldehyde, monoketones, and β‐diketones. In marked contrast, the pollen headspace volatiles showed a wide qualitative and quantitative variability among all samples per species, whereby the variability was more pronounced in R. bulbosus. Hence, the highly species‐specific pollenkitt lipids may provide pollinators with more reliable information on pollen identity.
Fluorenyl Hexa‐peri‐hexabenzocoronene‐Dendritic Oligothiophene Hybrid Materials: Synthesis, Photophysical Properties, Self‐Association Behaviour and Device Performance
Authors: Wong Wallace W. H. , Ma Chang‐Qi , Pisula Wojciech , Mavrinskiy Alexey , Feng Xinliang , Seyler Helga , Jones David J. , Müllen Klaus , Bäuerle Peter , Holmes Andrew B. 
Published: April 2011

AbstractApart from molecular properties, intermolecular forces play a vital role in defining the performance of organic electronic devices. This is particularly relevant in bulk heterojunction (BHJ) solar cells in which the arrangement of electron‐donor and ‐acceptor materials into distinct crystalline phases of ideal size and distribution can lead to better power conversion efficiencies. In this study, a series of fluorenyl hexa‐peri‐hexabenzocoronenes (FHBC) decorated with thiophene dendrons (DOT) of variable size was obtained by using a convergent synthetic approach. With such variety of molecular sizes and shapes in hand, the objective of this study is to highlight the relationships between molecular properties, bulk properties and device performance. Correlations between π–π stacking ability and dendrimer generation were established from self‐organisation studies in solution and solid state. The synergistic combination of molecular organisation at the nanoscale and photophysical characteristics derived from the FHBC and DOT moieties leads to a notable improvement of the photovoltaic performance.
Probing Peptide–Inorganic Surface Interaction at the Single Molecule Level Using Force Spectroscopy
Authors: Landoulsi Jessem , Dupres Vincent 
Published: April 2011

AbstractWe investigate the interaction between D‐Ala‐D‐Ala peptide and a stainless steel (SS) surface by AFM force spectroscopy with view to understand the role and nature of interfacial processes at the single molecule level. For this purpose, force–distance curves were recorded between the D‐Ala‐D‐Ala modified tip and the SS surface in NaHCO3‐enriched medium. The SS surface was prepared in a way that allows iron oxide species, presumably FeOOH, to be formed and remains stable during AFM measurements. Dynamic force measurements show that the unbinding force linearly increases with the logarithm of the loading rate, as generally observed for receptor–ligand complexes. Our results reveal also the existence of two regimes, suggesting the presence of multiple energy barriers in the energy landscape. From these dynamic force spectroscopy measurements, the kinetic off‐rate constant is determined. An average unbinding force in the range of 50–300 pN is obtained, depending on the loading rate. Accordingly, in a medium in which the electrostatic interactions are not dominating, the binding mechanism of the peptide and SS surface cannot be attributed to covalent bonds and may be due to a combination of van der Waals and hydrogen bonds. Our findings open up new way to probe peptide–inorganic surface interactions and to understand the mechanism of peptide specific binding which is of particular interest in the design of hybrid materials.
“Conflict defines origins”: Identity transformations of Sudanese refugees in Cairo
Authors: Mahmoud Hala W. 
Published: April 2011

AbstractThis study explores the effects of conflict on the identities of Sudanese refugees back in Sudan and then in Cairo, namely the experience of ambiguous, ambivalent, and conflicting identities. The conflict in Sudan caused multiple ruptures to the refugees' previously established identities. In Egypt, they come into contact and conflict with the host community, organizations, and fellow Sudanese from different regions or ethnic backgrounds, which creates tensions in religious, tribal, or ethnic identities. Such identity issues were manifested in extreme form during the tragic 2005 Sudanese refugee sit‐in. The conclusion sheds light on implications for conflict resolution.
Judging the acceptability of amnesties: A Togolese perspective
Authors: Kpanake Lonzozou , Mullet Etienne 
Published: April 2011

AbstractThe relationships between the circumstances in which amnesties are granted and Togolese laypeople's judgments of their acceptability were examined. The 351 participants were instructed to read stories created by the authors in which a former police officer testified in front of a commission to receive amnesty. The stories were based on a five‐factor design: quality of the information revealed, presence‐absence of apologies, opportunity given to the victims for telling their story, compensation, and punishment of the applicant. Several interactions involving the truth and the apology factors were observed: Acceptability required the simultaneous presence of several positive aspects.
Achieving reconciliation through prosecution in the courts: Lessons from Rwanda
Authors: Mukherjee Geetanjali 
Published: April 2011

AbstractIn the aftermath of innumerable genocides and civil wars, the Nuremburg promise of “never again” seems a fast‐fading dream. Despite considerable resources being allocated toward prosecuting individuals for international crimes, there is a sense that there has been no justice for the victims and that they have provided no sense of deterrence. Are trials an effective method to bring about reconciliation postconflict, or are they simply a waste of precious resources better used to rehabilitate the victims? Studying the Rwandan postconflict prosecutions, this paper offers recommendations for maximizing available resources to provide an atmosphere in which reconciliation can become a reality.
Metabolic tests to determine risk for type 1 diabetes in clinical trials
Authors: Greenbaum Carla J. , Buckingham B. , Chase H. P. , Krischer J. ,   for the Diabetes Prevention Trial, Type 1 Diabetes (DPT‐1) Study Group
Published: April 2011

AbstractAimsEvaluate the reproducibility and relationship of various metabolic tests conducted as part of the Diabetes Prevention Trial—type 1 diabetes.MethodsCoefficients of variation, intraclass correlation coefficients, and Pearson correlations between the same metabolic tests performed at different times as well as the different tests were determined.ResultsFasting samples on the same day had a coefficient of variation of < 10 for C‐peptide, 11 for insulin, and 2 for glucose. Testing on separate days approximately doubled the variance. Stimulated insulin values had less variance than fasting values and there was only a moderate correlation between fasting and stimulated values on each test. While highly correlated, C‐peptide values from mixed meal tolerance tests are significantly lower than that obtained during oral glucose tolerance tests (OGTTs). Neither peak nor area under the curve C‐peptide on the oral glucose tolerance test was different between those with abnormal and normal glucose tolerance. Those with abnormal as compared with normal glucose tolerance had lower 30‐min C‐peptide and a longer time to peak C‐peptide.ConclusionsA large, multi‐centre trial, with tests performed over a decade‐long period, can provide robust data. C‐peptide data from oral glucose tolerance tests and mixed meal tolerance tests differ; therefore, the same stimulation test should be used to evaluate changes in beta cell function over time. Worsening glucose tolerance is associated with lower C‐peptide at 30 min and a delay in peak secretion on the oral glucose tolerance test. This Diabetes Prevention Trial—type 1 diabetes data can be used in planning parameters for future studies, including evaluation of new algorithms to determine risk of disease. Copyright © 2011 John Wiley & Sons, Ltd.
Transient phenomena of disk MHD generator due to change of load resistance
Authors: Koka Hidetoshi , Okuno Yoshihiro , Yamasaki Hiroyuki 
Published: April 2011

AbstractThe results of an experimental study on transient phenomena in a closed cycle disk MHD generator are described in this paper. The transient phenomena were caused by a steplike change of load resistance during testing of the shock‐tube driven disk MHD generator. The load resistance was varied by using an IGBT (insulated gate bipolar transistor) installed in the load circuit. When the load resistance was changed from 0.096 Ω to 2.5 Ω, overshoot of the Hall output voltage and of the Hall electric field was observed, and a large fluctuation of static pressure was also observed. At the same time, a spikelike increase of the cesium recombination continuum and line spectrum appeared just after the load change. The results of quasi‐one‐ dimensional numerical simulation indicate that the observed overshoot was caused by the following phenomena: (1) a steep reduction of the Hall current and a steep increase in both the Faraday current and the electrical conductivity and (2) a slow reduction of the gas velocity due to the enhanced retarding force. Furthermore, the measured spikelike increase of the radiation intensity was ascribed to an increase of electron temperature and electron number density due to a steep increase of Joule heating. © 2011 Wiley Periodicals, Inc. Electr Eng Jpn, 175(4): 34–42, 2011; Published online in Wiley Online Library (wileyonlinelibrary.com). DOI 10.1002/eej.21004
Introducing a phase‐advanced rectifier circuit for reduction of distribution system reactive power
Authors: Aizawa Tadao 
Published: April 2011

AbstractThe excessive input of phase‐advanced capacitors by customers has been posing a problem to date. To deal with this problem, the installation of phase‐advanced capacitors on the low‐voltage side was recommended, but it does not presently seem to have produced the expected effect. As a solution, a phase‐advanced rectifier circuit, integrated from rectifier circuit built‐in equipment and a phase‐advanced capacitor, is proposed and the effect of its introduction is discussed. This method is confirmed to be effective for the reduction of reactive power, because the receiving‐end voltage and current waveform distortion are improved. In particular, the number of capacitors introduced into the system under light load is reduced. © 2011 Wiley Periodicals, Inc. Electr Eng Jpn, 175(4): 1–9, 2011; Published online in Wiley Online Library (wileyonlinelibrary.com). DOI 10.1002/eej.21109
Partially Hydrogenated 7‐Oxa[5]helicenes and [5]Helicenes: Synthesis, Structures, and Dynamics
Authors: Goel Atul , Verma Deepti , Pratap Ramendra , Taneja Gaurav , Hemberger Yasmin , Knauer Michael , Raghunandan Resmi , Maulik Prakas Ranjan , Ram Vishnu Ji , Bringmann Gerhard 
Published: April 2011

AbstractAn efficient and convenient synthesis of partially hydrogenated functionalized [5]helicenes and oxa[5]helicenes, such as (1,2,5,6‐tetrahydro‐3‐oxadibenzo[c,g]phenanthren‐4‐ylidene)acetonitriles 6 and (5,6‐dihydro‐3‐oxadibenzo[c,g]phenanthren‐4‐ylidene)acetonitriles 8, has been developed through base‐catalyzed ring transformation of 5,6‐dihydro‐4‐amin‐1‐yl‐2‐oxo‐2H‐benzo[h]chromene‐3‐carbonitriles 4 with 2‐tetralones 5. The molecular structures of the partially hydrogenated oxahelicenes were examined by spectroscopic methods and by X‐ray crystallographic analysis. To calculate the inversion barrier of the helimeric enantiomers P‐6e and M‐6e and of P‐8a and M‐8a, the molecular geometries of both the ground and the transition states were optimized by density functional theory (DFT) using B3LYP/6‐311G*. Based on these structures, RI‐SCS‐MP2/TZVP single‐point energies (ORCA) were calculated to permit a prediction of the rotational barrier. The accuracy of the calculated value for 6e was confirmed by Dynamic Nuclear Magnetic Resonance (DNMR) experiments with line‐shape analysis. Our ring‐transformation protocol provides easy access to functionalized helicenes and heterohelicenes with the flexibility of substituent variations and opens new perspectives for further exploration.
Electrochemical Immunosensor Based on Metal Nanoparticles for Cardiac Myoglobin Detection in Human Blood Plasma
Authors: Suprun Elena V. , Shilovskaya Alla L. , Lisitsa Alexander V. , Bulko Tatiana V. , Shumyantseva Victoria V. , Archakov Alexander I. 
Published: April 2011

AbstractCardiac myoglobin detection was based on direct electron transfer between the Fe(III)‐heme and the electrode surface that was modified with metal nanoparticles stabilized by didodecyldimethylammonium bromide and antibodies. Gold, silver and copper nanoparticles were tested as catalysts of the Fe(III)/Fe(II) electrode process. All experiments were carried out with human blood plasma samples of healthy donors and patients with acute myocardial infarction. The method proposed does not require labeled secondary antibodies. Immunosensor has a detection limit of 5 ng/mL and a broad range of working concentrations. The whole procedure takes 20 minutes and can be used to establish the diagnosis of acute myocardial infarction.
Ordered Macroporous Ruthenium Oxide Electrodes for Potentiometric and Amperometric Sensing Applications
Authors: Lenz J. , Trieu V. , Hempelmann R. , Kuhn A. 
Published: April 2011

AbstractWe report two methods to prepare ordered macroporous ruthenium oxide electrodes based on a template approach and their possible applications as potentiometric and amperometric sensors. The very stable porous electrodes have been prepared using two techniques to assemble the colloidal template: the controlled evaporation (CE) technique and the Langmuir–Blodgett (LB) technique, followed by electrochemical deposition of ruthenium oxide. The increased surface area of the macroporous structure makes them attractive for electroanalytical applications such as potentiometric and amperometric sensors as is illustrated for pH sensing and direct oxidation of NADH, which is an important ingredient in dehydrogenase based biosensors.
Molecular diagnosis of dermatofibrosarcoma protuberans: A comparison between reverse transcriptase‐polymerase chain reaction and fluorescence in situ hybridization methodologies
Authors: Salgado Rocío , Llombart Beatriz , M. Pujol Ramon , Fernández‐Serra Antonio , Sanmartín Onofre , Toll Agustí , Rubio Luis , Segura Sonia , Barranco Carlos , Serra‐Guillén Carlos , Yébenes Mireia , Salido Marta , Traves Víctor , Monteagudo Carlos , Sáez Empar , Hernández Teresa , de Álava Enrique , Llombart‐Bosch Antonio , Solé Francesc , Guillén Carlos , Espinet Blanca , López‐Guerrero Jose A. 
Published: April 2011

AbstractDermatofibrosarcoma protuberans (DFSP) is characterized by the presence of the t(17;22)(q22;q13) that leads to the fusion of the COL1A1 and PDGFB genes. This translocation can be detected by multiplex reverse transcriptase‐polymerase chain reaction (RT‐PCR) or fluorescence in situ hybridization (FISH) techniques. We have evaluated the usefulness of a dual color dual fusion FISH probe strategy for COL1A1/PDGFB detection in a series of 103 archival DFSPs and compared the obtained results with RT‐PCR analyses. FISH and RT‐PCR were carried out on paraffin embedded tissue samples. Regarding the RT‐PCR approach, all COL1A1 exons and exon 2 of PDGFB were evaluated. Sensitivity, specificity, positive and negative predictive values were assessed considering the histological diagnosis as the gold standard. We also analyzed the relationship between the genetic findings and the clinicopathological variables of the tumors. The COL1A1/PDGFB translocation was detected in 93% of DFSP. Both techniques showed a similar specificity (100%), but FISH was more sensitive than RT‐PCR (90% vs. 72%). Regarding, clinicopathological features, a higher percentage of positive cells detected by FISH was significantly associated with the fibrosarcomatous DFSP variant (P < 0.001). Interestingly, all CD34 negative DFSP (n = 5) were positive for COL1A1/PDGFB translocation by both techniques. In conclusion, the majority of DFSP harbor the COL1A1/PDGFB translocation and FISH technique should be recommended as a routine diagnostic tool, especially in cases showing unusual histopathological subtypes and/or immunohistochemical features. © 2011 Wiley‐Liss,Inc.
Changes in resting‐state brain networks in writer's cramp
Authors: Mohammadi Bahram , Kollewe Katja , Samii Amir , Beckmann Christian F. , Dengler Reinhard , Münte Thomas F. 
Published: April 2011

AbstractObjectives:Writer's cramp (WC) is characterized by excessive cocontractions of agonist and antagonist hand and forearm muscles during writing. Changes in functional magnetic resonance imaging activation patterns in such conditions can be ambiguous as they might either reflect some aspect of the primary pathophysiological mechanism or, alternatively, may be the result of adaptive actions during task execution. To circumvent this problem, we examined WC patients during rest, i.e., without a task, using independent component analysis (ICA) applied to the blood oxygen level‐dependent time series.Methods:Functionally connected brain networks during rest were defined by ICA to assess differences between WC patients (n = 16) and healthy controls (n = 16). Analysis was carried out using FMRIB's Software Library.Results:Two functional networks showed between‐group differences, the sensorimotor network and the default‐mode network. In WC patients, the connectivity was reduced in the left postcentral area and increased in basal ganglia in contrast to healthy controls. These changes were not reversed after treatment with botulinum toxin.Conclusions:In line with other studies, the results show a dysfunction in cortico‐subcortical circuits in WC involving somatosensory cortex, areas interfacing the sensory and motor systems, and putamen contralateral to symptomatic hand. Hum Brain Mapp, 2012. © 2011 Wiley Periodicals, Inc.
High‐risk human papillomavirus in nasopharyngeal carcinoma
Authors: Singhi Aatur D. , Califano Joseph , Westra William H. 
Published: April 2011

AbstractBackgroundHuman papillomavirus (HPV), a cause of oropharyngeal carcinoma, has also been implicated as an etiologic agent in nasopharyngeal carcinomas.MethodsWe performed p16 immunohistochemistry and in situ hybridization for Epstein–Barr virus (EBV) and HPV on 45 carcinomas of the nasopharynx.ResultsThirty‐four (76%) carcinomas were EBV‐positive/HPV‐negative, 7 (16%) were EBV‐negative/HPV‐negative, and 4 (9%) were EBV‐negative/HPV‐positive. HPV was more likely to be detected in carcinomas from white patients than non‐white patients (16% vs 0%; p = .03). Of the 3 patients with HPV‐positive carcinomas and available staging information, all were found to have extension into the oropharynx. All HPV‐positive carcinomas were p16 positive, but none of the HPV‐negative carcinomas were p16 positive (p < .001).ConclusionHPV can be detected in a subset of carcinomas involving the nasopharynx, but many of these may represent extension from an oropharyngeal primary. P16 immunohistochemistry is a reliable marker for separating EBV‐related and HPV‐related carcinomas of Waldheyer's ring. © 2011 Wiley Periodicals, Inc. Head Neck, 2012.