bluuebunny/crossref_metadata_2025_split huggingface dataset:
A European phylogeography of Rhinanthus minor compared to Rhinanthus angustifolius: unexpected splits and signs of hybridization
Authors: Vrancken Jérôme , Brochmann Christian , Wesselingh Renate A. 
Published: June 2012

AbstractRhinanthus minor and Rhinanthus angustifolius (Orobanchaceae) are annual hemiparasites, which occur sympatrically in Europe and are known to hybridize. We studied chloroplast and nuclear (amplified fragment length polymorphism [AFLP]) diversity in R. minor and compared genetic structuring in this species with R. angustifolius by analyzing the AFLP data for both species simultaneously. The AFLP data revealed that populations in Italy, Greece, and southeast Russia initially identified as R. minor were so distant from the other R. minor populations that they probably belong to another, yet unidentified taxon, and we refer to them as Rhinanthus sp. R. minor s.s. showed a clear geographic genetic structure in both the chloroplast DNA (cpDNA) and nuclear genome. The simultaneous analysis of both species shed new light on the previously published findings for R. angustifolius, because some populations now turned out to belong to R. minor. The admixture analysis revealed very few individuals of mixed R. minor–R.angustifolius ancestry in the natural populations in the west of Europe, while admixture levels were higher in the east. The combined haplotype network showed that haplotype H1 was shared among all species and is likely to be ancestral. H2 was more abundant in R. angustifolius and H3 in R. minor, and the latter probably arose from H1 in this species in the east of Europe. The occurrence of H3 in R. angustifolius may be explained by introgression from R. minor, but without interspecific admixture, these are likely to have been old hybridization events. Our study underlines the importance of including related species in phylogeographic studies.
Long‐term breeding phenology shift in royal penguins
Authors: Hindell Mark A. , Bradshaw Corey J. A. , Brook Barry W. , Fordham Damien A. , Kerry Knowles , Hull Cindy , McMahon Clive R. 
Published: June 2012

AbstractThe Earth's climate is undergoing rapid warming, unprecedented in recent times, which is driving shifts in the distribution and phenology of many plants and animals. Quantifying changes in breeding phenology is important for understanding how populations respond to these changes. While data on shifts in phenology are common for Northern Hemisphere species (especially birds), there is a dearth of evidence from the Southern Hemisphere, and even fewer data available from the marine environment. Surface air temperatures at Macquarie Island have increased by 0.62°C during the 30‐year study period (0.21°C decade−1) and royal penguins (Eudyptes schlegeli) commenced egg laying on average three days earlier in the 1990s than during the 1960s. This contrasts with other studies of Southern Ocean seabirds; five of nine species are now breeding on average 2.1 days later than during the 1950s. Despite the different direction of these trends, they can be explained by a single underlying mechanism: resource availability. There was a negative relationship between the Southern Annular Mode (SAM) and median laying date of royal penguins, such that low‐productivity (low SAM) years delayed laying date. This accords with the observations of other seabird species from the Antarctic, where later laying dates were associated with lower sea ice and lower spring productivity. The unifying factor underpinning phenological trends in eastern Antarctica is therefore resource availability; as food becomes scarcer, birds breed later. These changes are not uniform across the region, however, with resource increases in the subantarctic and decreases in eastern Antarctica.
P‐OR Functional Phosphanido and/or Li/OR Phosphinidenoid Complexes?
Authors: Duan Lili , Schnakenburg Gregor , Daniels Jörg , Streubel Rainer 
Published: June 2012

AbstractP‐H,P‐OR‐substituted phosphane complexes 3a–e have been synthesized by two methods: (1) the thermal reaction of 2H‐azaphosphirene complex 1 with methanol, n‐butanol, or ethylene glycol monomethyl ether (3b,c,e) or (2) the reaction of P‐chlorophosphane complex 2 with appropriate sodium phenolate salts (3a,d). All the complexes 3a–e were obtained in good yields and fully characterized by NMR, IR, MS, and elemental analysis. Furthermore, the structures of 3a, 3d and 3e were confirmed unambiguously by X‐ray analysis. The deprotonation of complexes 3a–e by using lithium diisopropylamide in the presence of 12‐crown‐4 led to phosphinidenoid complexes 4a–e, which exhibit downfield 31P resonances and small tungsten–phosphorus coupling constants. Studies on the reactivity of complexes 4a–c,e revealed a “phosphanido‐type” reactivity, and only for complex 4d, a thermally labile complex, was evidence found for a “phosphinidene‐type” reactivity.
Total Synthesis of Potent Antitumor Macrolide (–)‐Zampanolide: An Oxidative Intramolecular Cyclization‐Based Strategy
Authors: Ghosh Arun K. , Cheng Xu , Bai Ruoli , Hamel Ernest 
Published: June 2012

AbstractA detailed account of the enantioselective total synthesis of (–)‐zampanolide, a macrolide marine natural product with high anticancer activity, is described. For the synthesis of the 4‐methylenetetrahydropyran unit of (–)‐zampanolide, we initially relied upon an oxidative C–H activation of an alkenyl ether and intramolecular cyclization to provide the substituted tetrahydropyran ring. However, this strategy was unsuccessful. Subsequently, we found that a cinnamyl ether is critical for the successful oxidative intramolecular cyclization reaction. The synthesis also features a cross‐metathesis reaction for the construction of a trisubstituted olefin, a ring‐closing metathesis to form a highly functionalized macrolactone, and a chiral phosphoric acid promoted formation of an N‐acyl aminal to furnish (–)‐zampanolide stereoselectively and in good yield. The synthetic (–)‐zampanolide had effects on cultured cells and on tubulin assembly consistent with the properties reported for the natural product.
Monte Carlo simulations on the thermodynamic properties of high‐density gases
Authors: Hu Shide 
Published: June 2012

SUMMARYThe thermodynamic properties of Ar, H2 and CH4 at high‐density conditions are studied using Monte Carlo simulations. The isotherms of Ar at 500K, H2 at 1000K and CH4 at 500K are obtained respectively. To validate the accuracy of the simulation results, the thermodynamic properties of these gases are also studied with van der Waals equation and compared with the reference data. The agreement with reference shows that Monte Carlo method can produce reliable thermodynamic properties of high‐density gases based on the accurate intermolecular potential model. Therefore, the accuracy of the simulations depends primarily on the accuracy of the potential model, and this dependence is also discussed. Copyright © 2012 John Wiley & Sons, Ltd.
Preliminary country‐scale assessment of carbon dioxide storage potential in Iran
Authors: Movagharnejad Kamyar , Emamgholivand Azadeh , Mousavi Hamed , Kordkheili Masoud Sheikhi 
Published: June 2012

AbstractThis study is a country‐scale assessment of the CO2 storage potential in Iran. Estimates are given of the CO2 storage capacity in saline water‐bearing sedimentary rocks and enhanced oil and gas recovery operations. The results suggest that of the order of 70 Gt CO2 storage capacity may be present in saline aquifers, approximately 19 Gt CO2 storage capacity could result from enhanced oil recovery, and 1.1 Gt capacity could result from enhanced gas recovery, indicating great potential for CO2 storage in Iran. These results must be treated with great caution however, due to the scoping nature of the study. More detailed studies of the most promising basins are recommended. Enhanced oil recovery appears to be the most promising route to geological CO2 storage in Iran because of the potential economic benefits. © 2011 Society of Chemical Industry and John Wiley & Sons, Ltd
Lab on a chip technologies for algae detection: a review
Authors: Schaap Allison , Rohrlack Thomas , Bellouard Yves 
Published: June 2012

AbstractOver the last few decades, lab on a chip technologies have emerged as powerful tools for high‐accuracy diagnosis with minute quantities of liquid and as tools for exploring cell properties in general. In this paper, we present a review of the current status of this technology in the context of algae detection and monitoring. We start with an overview of the detection methods currently used for algae monitoring, followed by a review of lab on a chip devices for algae detection and classification, and then discuss a case study based on our own research activities. We conclude with a discussion on future challenges and motivations for algae‐oriented lab on a chip technologies. (© 2012 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)
Estradiol protects adipose tissue–derived stem cells against H2O2‐induced toxicity
Authors: Taskiran Dilek , Evren Vedat 
Published: June 2012

AbstractOxidative stress is associated with various pathophysiological processes, including cell survival, adhesion, apoptosis, and cancer. In the present study, we aimed to evaluate the effects of H2O2‐induced toxicity on adipose tissue–derived stem cells (ADSCs) and whether 17β‐estradiol (E2) has protective effects on these cells. ADSCs derived from adult Sprague–Dawley rats were pretreated with different doses of E2 for 24 h and then exposed to 200 µM H2O2 for 4 h. Incubation of ADSCs with H2O2‐decreased cell viability in a concentration‐dependent fashion (p < 0.0001), whereas pretreatment of these cells with E2 significantly reversed toxicity (p < 0.05), inhibited apoptotic changes, and decreased lipid peroxidation (p < 0.0005). Our findings suggest that E2 protects ADSCs from oxidative‐induced cell death, and therefore, it may be used to improve the survival rate and regenerative capacity of stem cells. © 2012 Wiley Periodicals, Inc. J Biochem Mol Toxicol 26:301–307, 2012; View this article online at wileyonlinelibrary.com. DOI 10.1002/jbt.21421
On orthogonality constrained multiple core‐hole states and optimized effective potential method
Authors: Glushkov V. N. , Assfeld X. 
Published: June 2012

AbstractAn attempt to construct a multiple core‐hole state within the optimized effective potential (OEP) methodology is presented. In contrast to the conventional Δ‐self‐consistent field method for hole states, the effects of removing an electron is achieved using some orthogonality constraints imposed on the orbitals so that a Slater determinant describing a hole state is constrained to be orthogonal to that of a neutral system. It is shown that single, double, and multiple core‐hole states can be treated within a unified framework and can be easily implemented for atoms and molecules. For this purpose, a constrained OEP method proposed earlier for excited states (Glushkov and Levy, J. Chem. Phys. 2007, 126, 174106) is further developed to calculate single and double core ionization energies using a local effective potential expressed as a direct mapping of the external potential. The corresponding equations, determining core‐hole orbitals from a one‐particle Schrödinger equation with a local potential as well as correlation corrections derived from the second‐order many‐body perturbation theory are given. One of the advantages of the present direct mapping formulation is that the effective potential, which plays the role of the Kohn–Sham potential, has the symmetry of the external potential. Single and double core ionization potentials computed with the presented scheme were found to be in agreement with data available from experiment and other calculations. We also discuss core‐hole state local potentials for the systems studied. © 2012 Wiley Periodicals, Inc.
Diffusion‐tensor MRI reveals the complex muscle architecture of the human forearm
Authors: Froeling Martijn , Nederveen Aart J. , Heijtel Dennis F.R. , Lataster Arno , Bos Clemens , Nicolay Klaas , Maas Mario , Drost Maarten R. , Strijkers Gustav J. 
Published: June 2012

AbstractPurpose:To design a time‐efficient patient‐friendly clinical diffusion tensor MRI protocol and postprocessing tool to study the complex muscle architecture of the human forearm.Materials and Methods:The 15‐minute examination was done using a 3 T system and consisted of: T1‐weighted imaging, dual echo gradient echo imaging, single‐shot spin‐echo echo‐planar imaging (EPI) diffusion tensor MRI. Postprocessing comprised of signal‐to‐noise improvement by a Rician noise suppression algorithm, image registration to correct for motion and eddy currents, and correction of susceptibility‐induced deformations using magnetic field inhomogeneity maps. Per muscle one to five regions of interest were used for fiber tractography seeding. To validate our approach, the reconstructions of individual muscles from the in vivo scans were compared to photographs of those dissected from a human cadaver forearm.Results:Postprocessing proved essential to allow muscle segmentation based on combined T1‐weighted and diffusion tensor data. The protocol can be applied more generally to study human muscle architecture in other parts of the body.Conclusion:The proposed protocol was able to visualize the muscle architecture of the human forearm in great detail and showed excellent agreement with the dissected cadaver muscles. J. Magn. Reson. Imaging 2012. © 2012 Wiley Periodicals, Inc.
Shifting imaging targets in multiple sclerosis: From inflammation to neurodegeneration
Authors: Vigeveno René M. , Wiebenga Oliver T. , Wattjes Mike P. , Geurts Jeroen J.G. , Barkhof Frederik 
Published: June 2012

AbstractClassically multiple sclerosis (MS) has been regarded as an auto‐immune disease of the white matter in the central nervous system leading to severe disability over the course of several decades. Current therapeutic strategies in MS are mostly based on either immune suppression or immune modulation. Although effective in decreasing relapse frequency and severity as well as delaying disease progression, MS pathology ensues nonetheless. In the last decade it became evident that gray matter pathology plays an important role in disease progression and helps explaining certain aspects of MS‐related disability such as cognitive decline. Conventional MRI outcome measures commonly used in clinical trials are sufficient to demonstrate an anti‐inflammatory drug‐effect but lack pathological specificity and are poor to moderate predictors of disability. In this article, we review new insights in gray matter pathology and functional reorganization in MS and how these novel fields in MS research may validate and establish new MRI outcome measures, aid in the development of new therapeutic strategies for neuroprotection and neurorepair, and may lead to development of novel predictive measures of disability and disease progression in MS. J. Magn. Reson. Imaging 2012; 36:1–19. © 2012 Wiley Periodicals, Inc.
A daily homogenized temperature data set for Australia
Authors: Trewin Blair 
Published: June 2012

AbstractA new homogenized daily maximum and minimum temperature data set, the Australian Climate Observations Reference Network—Surface Air Temperature data set, has been developed for Australia. This data set contains data from 112 locations across Australia, and extends from 1910 to the present, with 60 locations having data for the full post‐1910 period.These data have been comprehensively analysed for inhomogeneities and data errors ensuring a set of station temperature data which are suitable for the analysis of climate variability and trends. For the purposes of merging station series and correcting inhomogeneities, the data set has been developed using a technique, the percentile‐matching (PM) algorithm, which applies differing adjustments to daily data depending on their position in the frequency distribution. This method is intended to produce data sets that are homogeneous for higher‐order statistical properties, such as variance and the frequency of extremes, as well as for mean values. The PM algorithm is evaluated and found to have clear advantages over adjustments based on monthly means, particularly in the homogenization of temperature extremes. Copyright © 2012 Royal Meteorological Society
Determination of amatoxins in different tissues and development stages of Amanita exitialis
Authors: Hu Jinsong , Zhang Ping , Zeng Jun , Chen Zuohong 
Published: June 2012

AbstractBACKGROUND: Mushroom poisoning is the main cause of human death by food poisoning in China. Most lethal mushrooms belong to the Amanita genus, whose amatoxins are responsible for the death of humans. Amanita exitialis is a lethal white mushroom commonly found in Guangdong Province, China. In this study the contents and distribution of the major amatoxins in different tissues and development stages of A. exitialis were systematically analysed.RESULTS: The amatoxin contents and distribution in six different mushroom tissues of A. exitialis were analysed by reverse phase high‐performance liquid chromatography. The highest concentrations of amatoxins were found in the gills and pileus, followed by the stipe and annulus, with the lowest concentrations in the volva and spores. Further analysis of mushrooms in different development stages showed that the amatoxin content was relatively high and steady during early development, reached its peak when the fruit body was in the vigorous growth stage and then decreased sharply when the mushroom entered its mature stage. Furthermore, the α‐amanitin/β‐amanitin ratio varied significantly in different tissues but remained constant within a specific tissue throughout development.CONCLUSION: The contents and distribution of amatoxins in different tissues and development stages of A. exitialis are markedly different. The distribution of α‐amanitin and β‐amanitin varies in different tissues but remains constant throughout development. Copyright © 2012 Society of Chemical Industry
Lycium barbarum polysaccharide inhibits the proliferation of HeLa cells by inducing apoptosis
Authors: Zhu Cai‐Ping , Zhang Sheng‐Hua 
Published: June 2012

AbstractBACKGROUND: Lycium barbarum polysaccharide (LBP), isolated with boiling water from the famous Chinese medicinal herb Lycium barbarum fruits, is one of the most important functional constituents in Lycium barbarum. In this study the effects of LBP on cell proliferation, cell cycle and apoptosis in human cervical carcinoma cells (HeLa cells) were investigated.RESULTS: LBP could inhibit the proliferation of HeLa cells by changing cell cycle distribution and inducing apoptosis. In addition, the loss of mitochondrial transmembrane potential (Δψm) was observed by flow cytometry and the increase of intracellular Ca2+ concentration was detected by laser scanning confocal microscope in apoptotic cells. At the same time, the nitric oxide content, nitric oxide synthase and inducible nitric oxide synthase activities were also increased.CONCLUSION: The inhibitory effect of LBP on the proliferation of HeLa cells was caused by inducing apoptosis through the mitochondrial pathway. The results showed that LBP can be developed as a potential chemotherapeutic agent candidate against human cervical cancer. Copyright © 2012 Society of Chemical Industry
Microalgae as an alternative source of omega‐3 long chain polyunsaturated fatty acids
Authors: Ryckebosch Eline , Bruneel Charlotte , Muylaert Koenraad , Foubert Imogen 
Published: June 2012

AbstractThe health benefits of omega‐3 long chain polyunsaturated fatty acids (omega‐3 LC‐PUFA) are recognized worldwide. The traditional source of omega‐3 LC‐PUFA is fish. However, global consumer needs cannot be supplied by the current global fish harvest. Therefore, new sources of omega‐3 LC‐PUFA have to be found. Microalgae are producers of omega‐3 LC‐PUFA and a potential alternative for seafood. Other sources of omega‐3 LC‐PUFA include krill oil, calamari oil and genetically engineered land plant crops.
Frying oil use in China
Authors: Fan Liuping , Eskin N.A. Michael 
Published: June 2012

AbstractThe rapid development of China's economy has resulted in a dramatic increase in the production and purchase of instant fried food products by consumers. China's food industry has relied largely on the importation of soybean oil and palm oil. Palm oil is widely used by the commercial food industry because of its high oxidative stability and low cost. In contrast, the demand for rapeseed oil and peanut oil has gradually increased but only for domestic frying. In the future, specialized frying oils with improved stability and function will be developed for industrial and domestic frying in China.
Novel Thermally Conductive Thermoplastic/Ceramic Composite Foams
Authors: Chan Ellen , Leung Siu N. , Khan Muhammad O. , Naguib Hani E. , Dawson Francis , Adinkrah Vincent 
Published: June 2012

AbstractMultifunctional materials that are lightweight and thermally conductive but electrically insulating are important for modern electronics, computer, and telecommunication technologies. Here, a novel foam structure of a polymer/matrix composite filled with ceramic platelets with improved thermal conductivity is reported. Such improvement is caused by the stress‐induced alignment of thermally conductive fillers in the cell wall of the plastic foam. The foam structure is very promising for use as a lightweight electronic packaging material owing to its light weight, thermal conduction ability, electrical insulation, and good processability.magnified image
Mark Krein's method of directing functionals and singular potentials
Authors: Fulton Charles , Langer Heinz , Luger Annemarie 
Published: June 2012

AbstractIt is shown that M. Krein's method of directing functionals can be used to prove the existence of a scalar spectral measure for certain Sturm–Liouville equations with two singular endpoints. The essential assumption is the existence of a solution of the equation that is square integrable at one singular endpoint and depends analytically on the eigenvalue parameter.
Kinetic Study of 1,5‐Hydrogen Transfer Reactions of Methyl Acrylate and Butyl Acrylate Using Quantum Chemistry
Authors: Yu Xinrui , Broadbelt Linda J. 
Published: June 2012

Abstract1,5‐Hydrogen transfer reactions in methyl acrylate and butyl acrylate free‐radical polymerization are studied using quantum chemistry and transition state theory to estimate the kinetic parameters (ktr, Ea, and A) with tetrameric radicals, requiring a number of atoms that ranks among the largest polymeric mimics to date. A two‐step transformation accounted for the overall reaction: rotation from an extended conformation to a coiled conformation and abstraction of the fifth hydrogen atom by the end‐chain radical. UB3LYP/6‐31G(d) was used for geometry optimization, validation of the transition states, and calculation of frequencies that were used to obtain thermodynamic properties. The more computationally demanding level of theory, MPWB1K/6‐31G(d,p), was used for calculation of the electronic energy. magnified image