bluuebunny/crossref_metadata_2025 huggingface dataset:
Cu(II)‐Promoted Oxidative Homocoupling Reaction of Terminal Alkynes in Supercritical Carbon Dioxide.
Authors: Jiang Huan‐Feng , Tang Jin‐Yu , Wang A‐Zhong , Deng Guo‐Hua , Yang Shao‐Rong
Published: July 2006

ChemInform is a weekly Abstracting Service, delivering concise information at a glance that was extracted from about 200 leading journals. To access a ChemInform Abstract, please click on HTML or PDF.
Synthetic Utilities of Ionic Liquid Supported NHPI Complex.
Authors: Koguchi Shinichi , Kitazume Tomoya
Published: July 2006

ChemInform is a weekly Abstracting Service, delivering concise information at a glance that was extracted from about 200 leading journals. To access a ChemInform Abstract, please click on HTML or PDF.
RuHCl(CO)(PPh3)3‐Catalyzed Chemoselective Transfer‐Hydrogenation of Enones Leading to Saturated Ketones.
Authors: Doi Takashi , Fukuyama Takahide , Horiguchi Jiro , Okamura Takahiro , Ryu Ilhyong
Published: July 2006

ChemInform is a weekly Abstracting Service, delivering concise information at a glance that was extracted from about 200 leading journals. To access a ChemInform Abstract, please click on HTML or PDF.
Selective N‐Alkylation of Anilines in Ionic Liquids.
Authors: Chiappe Cinzia , Piccioli Paolo , Pieraccini Daniela
Published: July 2006

ChemInform is a weekly Abstracting Service, delivering concise information at a glance that was extracted from about 200 leading journals. To access a ChemInform Abstract, please click on HTML or PDF.
A Non‐Fluorous Copper Catalyst for the Styrene Cyclopropanation Reaction in a Fluorous Medium.
Authors: Urbano Juan , Izarra Rocio , Gomez‐Ariza Jose Luis , Trofimenko Swiatoslaw , Diaz‐Requejo M. Mar , Perez Pedro J.
Published: July 2006

ChemInform is a weekly Abstracting Service, delivering concise information at a glance that was extracted from about 200 leading journals. To access a ChemInform Abstract, please click on HTML or PDF.
Design of Chiral Macrocyclic Complexes Based on trans‐Chelation of n:n Metal—Bidentate P,N‐ or N,N‐Ligands.
Authors: Hatano Manabu , Asai Takafumi , Ishihara Kazuaki
Published: July 2006

ChemInform is a weekly Abstracting Service, delivering concise information at a glance that was extracted from about 200 leading journals. To access a ChemInform Abstract, please click on HTML or PDF.
Novel Method for the Synthesis of α‐Bromocinnamaldehydes.
Authors: Shastin A. V. , Reznichenko A. L. , Lenkova O. N. , Balenkova E. S. , Nenaidenko V. G.
Published: July 2006

ChemInform is a weekly Abstracting Service, delivering concise information at a glance that was extracted from about 200 leading journals. To access a ChemInform Abstract, please click on HTML or PDF.
An Efficient and Novel Method for the Synthesis of Sulfinate Esters under Solvent‐Free Conditions.
Authors: Hajipour Abdol R. , Falahati Ali R. , Ruoho Arnold E.
Published: July 2006

ChemInform is a weekly Abstracting Service, delivering concise information at a glance that was extracted from about 200 leading journals. To access a ChemInform Abstract, please click on HTML or PDF.
Rhodium/Phosphoramidite‐Catalyzed Asymmetric Arylation of Aldehydes with Arylboronic Acids.
Authors: Jagt Richard B. C. , Toullec Patrick Y. , de Vries Johannes G. , Feringa Ben L. , Minnaard Adriaan J.
Published: July 2006

ChemInform is a weekly Abstracting Service, delivering concise information at a glance that was extracted from about 200 leading journals. To access a ChemInform Abstract, please click on HTML or PDF.
Ruthenium‐Catalyzed Isomerization of Oxa/Azabicyclic Alkenes: An Expedient Route for the Synthesis of 1,2‐Naphthalene Oxides and Imines.
Authors: Villeneuve Karine , Tam William
Published: July 2006

ChemInform is a weekly Abstracting Service, delivering concise information at a glance that was extracted from about 200 leading journals. To access a ChemInform Abstract, please click on HTML or PDF.
Phosphines Catalyzed Nucleophilic Addition of Azoles to Allenes: Synthesis of Allylazoles and Indolizines.
Authors: Virieux David , Guillouzic Anne‐Francoise , Cristau Henri‐Jean
Published: July 2006

ChemInform is a weekly Abstracting Service, delivering concise information at a glance that was extracted from about 200 leading journals. To access a ChemInform Abstract, please click on HTML or PDF.
Establishing the NHBoc Functionality as ortho‐Metalating Group for Furan.
Authors: Stanetty Peter , Kolodziejczyk Krzystztof , Roiban Gheorghe‐Doru , Mihovilovic Marko D.
Published: July 2006

ChemInform is a weekly Abstracting Service, delivering concise information at a glance that was extracted from about 200 leading journals. To access a ChemInform Abstract, please click on HTML or PDF.
Synthesis of New Trifluoromethylated Furans, Dihydrofurans and Butenolides Starting from γ‐Ketothioesters and Diisopropylamine.
Authors: Bouillon Jean‐Philippe , Kikelj Vincent , Tinant Bernard , Harakat Dominique , Portella Charles
Published: July 2006

ChemInform is a weekly Abstracting Service, delivering concise information at a glance that was extracted from about 200 leading journals. To access a ChemInform Abstract, please click on HTML or PDF.
A Novel Series of Arylsulfonylthiophene‐2‐carboxamidine Inhibitors of the Complement Component C1s.
Authors: Subasinghe Nalin L. , et al. et al.
Published: July 2006

ChemInform is a weekly Abstracting Service, delivering concise information at a glance that was extracted from about 200 leading journals. To access a ChemInform Abstract, please click on HTML or PDF.
The Triphenyl Phosphite—Chlorine Reagent in the Synthesis of Pyrroles from N‐Allylamides.
Authors: Spaggiari Alberto , Vaccari Daniele , Davoli Paolo , Prati Fabio
Published: July 2006

ChemInform is a weekly Abstracting Service, delivering concise information at a glance that was extracted from about 200 leading journals. To access a ChemInform Abstract, please click on HTML or PDF.
A Facile Synthesis of 9‐Dialkylamino‐9H‐pyrrolo[1,2‐a]indoles via Iminium Salts Generated from 2‐(Pyrrol‐1‐yl)benzaldehydes and Secondary Amine Hydrochlorides in the Presence of NaI/TMSCl/Et3N.
Authors: Kobayashi Kazuhiro , Takanohashi Atsushi , Hashimoto Kenichi , Morikawa Osamu , Konishi Hisatoshi
Published: July 2006

ChemInform is a weekly Abstracting Service, delivering concise information at a glance that was extracted from about 200 leading journals. To access a ChemInform Abstract, please click on HTML or PDF.
Cyclocondensation of 2‐(1‐Aryl‐5‐phenylpyrazol‐4‐yl)‐1H‐benzimidazoles with DMF Dimethylacetal.
Authors: Dzvinchuk I. B. , Lozinskii M. O.
Published: July 2006

ChemInform is a weekly Abstracting Service, delivering concise information at a glance that was extracted from about 200 leading journals. To access a ChemInform Abstract, please click on HTML or PDF.
The Preparation of 3‐Substituted 1,2‐Benzisothiazole‐1,1‐dioxides from the Condensation—Cyclization of Dilithiated β‐Ketoesters with Methyl 2‐(Aminosulfonyl)benzoate or 1,2‐Benzisothiazol‐3(2H)‐one‐1,1‐dioxide.
Authors: Meierhoefer Michelle A. , et al. et al.
Published: July 2006

ChemInform is a weekly Abstracting Service, delivering concise information at a glance that was extracted from about 200 leading journals. To access a ChemInform Abstract, please click on HTML or PDF.
Regioselective Synthesis of a New [1,2,3]‐Triazoles Directly from Imidates.
Authors: Hamdi N. , Fischmeister C. , Dixneuf P. H. , Nievas A. Romerosa
Published: July 2006

ChemInform is a weekly Abstracting Service, delivering concise information at a glance that was extracted from about 200 leading journals. To access a ChemInform Abstract, please click on HTML or PDF.
Synthesis of Phospholipase A2 Inhibitory Biflavonoids.
Authors: Chen Jianjun , Chang Hyeun Wook , Kim Hyun Pyo , Park Haeil
Published: July 2006

ChemInform is a weekly Abstracting Service, delivering concise information at a glance that was extracted from about 200 leading journals. To access a ChemInform Abstract, please click on HTML or PDF.
4‐Hydroxyquinol‐2‐ones. Part 86. Synthesis of Methyl (Ethyl) Esters of 1‐Substituted 4‐Amino‐2‐oxoquinoline‐3‐carboxylic Acids.
Authors: Ukrainets I. V. , Sidorenko L. V. , Gorokhova O. V.
Published: July 2006

ChemInform is a weekly Abstracting Service, delivering concise information at a glance that was extracted from about 200 leading journals. To access a ChemInform Abstract, please click on HTML or PDF.
Discovery of Novel Heterocyclic Factor VIIa Inhibitors.
Authors: Rai Roopa , et al. et al.
Published: July 2006

ChemInform is a weekly Abstracting Service, delivering concise information at a glance that was extracted from about 200 leading journals. To access a ChemInform Abstract, please click on HTML or PDF.
N‐Acyl and N‐Alkoxycarbonyl Derivatives of 1H‐1,2,3‐Triazolo[4,5‐c]pyridine: Preparation and Application.
Authors: Holt Jarle , Fiksdahl Anne
Published: July 2006

ChemInform is a weekly Abstracting Service, delivering concise information at a glance that was extracted from about 200 leading journals. To access a ChemInform Abstract, please click on HTML or PDF.
On the Synthesis of 5‐Ethyl Meldrum′s Acid.
Authors: Akue‐Gedu Rufine , El‐Hafidi Hayate , Rigo Benoit , Couturier Daniel
Published: July 2006

ChemInform is a weekly Abstracting Service, delivering concise information at a glance that was extracted from about 200 leading journals. To access a ChemInform Abstract, please click on HTML or PDF.
Synthesis and Antimicrobial Activity of New Benzofuranyl‐1,3‐benzoxazines and 1,3‐Benzoxazin‐2‐ones.
Authors: Ujjinamatada Ravi K. , Appala Raju S. , Agasimundin Yankanagouda S.
Published: July 2006

ChemInform is a weekly Abstracting Service, delivering concise information at a glance that was extracted from about 200 leading journals. To access a ChemInform Abstract, please click on HTML or PDF.
A New Synthesis of 4H‐1,4‐Benzothiazine Derivatives Based on Ring Closure of EWG‐Stabilized (2‐Isocyanophenylthio)methyl Anions.
Authors: Kobayashi Kazuhiro , Hayashi Kazutaka , Iitsuka Daisuke , Morikawa Osamu , Konishi Hisatoshi
Published: July 2006

ChemInform is a weekly Abstracting Service, delivering concise information at a glance that was extracted from about 200 leading journals. To access a ChemInform Abstract, please click on HTML or PDF.
Two‐Step Syntheses of 3‐Methyl and 3‐Phenyl‐1,2,4‐benzotriazines.
Authors: Khodja Mohamed , Moulay Saad , Boutoumi Hocine , Wilde Horst
Published: July 2006

ChemInform is a weekly Abstracting Service, delivering concise information at a glance that was extracted from about 200 leading journals. To access a ChemInform Abstract, please click on HTML or PDF.
Three New, 1‐Oxygenated ent‐8,9‐Secokaurane Diterpenes from Croton kongensis
Authors: Chen Wei , Yang Xiao‐Dong , Zhao Jing‐Feng , Yang Jing‐Hua , Zhang Hong‐Bin , Li Zi‐Yan , Li Liang
Published: July 2006

ChemInform is a weekly Abstracting Service, delivering concise information at a glance that was extracted from about 200 leading journals. To access a ChemInform Abstract, please click on HTML or PDF.
Design, Synthesis, and Biological Evaluation of a Scaffold for iGluR Ligands Based on the Structure of (‐)‐Dysiherbaine.
Authors: Cohen Jamie L. , Limon Agenor , Miledi Ricardo , Chamberlin A. Richard
Published: July 2006

ChemInform is a weekly Abstracting Service, delivering concise information at a glance that was extracted from about 200 leading journals. To access a ChemInform Abstract, please click on HTML or PDF.
Polyhydroxylated Bicyclic Ureas from Glycosyl Isocyanides.
Authors: Prosperi Davide
Published: July 2006

ChemInform is a weekly Abstracting Service, delivering concise information at a glance that was extracted from about 200 leading journals. To access a ChemInform Abstract, please click on HTML or PDF.
Total Synthesis of FR901464, an Antitumor Agent that Regulates the Transcription of Oncogenes and Tumor Suppressor Genes.
Authors: Albert Brian J. , Sivaramakrishnan Ananthapadmanabhan , Naka Tadaatsu , Koide Kazunori
Published: July 2006

ChemInform is a weekly Abstracting Service, delivering concise information at a glance that was extracted from about 200 leading journals. To access a ChemInform Abstract, please click on HTML or PDF.
2D Structure Depiction.
Authors: Clark Alex M. , Labute Paul , Santavy Martin
Published: July 2006

ChemInform is a weekly Abstracting Service, delivering concise information at a glance that was extracted from about 200 leading journals. To access a ChemInform Abstract, please click on HTML or PDF.
Prediction of Biological Targets for Compounds Using Multiple‐Category Bayesian Models Trained on Chemogenomics Databases.
Authors: Nidhi Nidhi , Glick Meir , Davies John W. , Jenkins Jeremy L.
Published: July 2006

ChemInform is a weekly Abstracting Service, delivering concise information at a glance that was extracted from about 200 leading journals. To access a ChemInform Abstract, please click on HTML or PDF.
Enhancing Specificity and Sensitivity of Pharmacophore‐Based Virtual Screening by Incorporating Chemical and Shape Features — A Case Study of HIV Protease Inhibitors.
Authors: Pandit Deepangi , So Sung‐Sau , Sun Hongmao
Published: July 2006

ChemInform is a weekly Abstracting Service, delivering concise information at a glance that was extracted from about 200 leading journals. To access a ChemInform Abstract, please click on HTML or PDF.
Metastable γ‐MnS Hierarchical Architectures: Synthesis, Characterization, and Growth Mechanism.
Authors: Zheng Yuanhui , Cheng Yao , Wang Yuansheng , Zhou Lihua , Bao Feng , Jia Chong
Published: July 2006

ChemInform is a weekly Abstracting Service, delivering concise information at a glance that was extracted from about 200 leading journals. To access a ChemInform Abstract, please click on HTML or PDF.
Specific Inhibitors of Plasmodium falciparum Thioredoxin Reductase as Potential Antimalarial Agents.
Authors: Adricopulo A. D. , Akoachere M. B. , Krogh R. , Nickel C. , McLeish M. J. , Kenyon G. L. , Arscott L. D. , Williams C. H. Jr. , Davioud‐Charvet E. , Becker K.
Published: July 2006

ChemInform is a weekly Abstracting Service, delivering concise information at a glance that was extracted from about 200 leading journals. To access a ChemInform Abstract, please click on HTML or PDF.
Phase Equilibrium in the Binary Systems AIVBVI. Part 1. The Systems Silicon—Chalcogen
Authors: Bletskan D. I.
Published: July 2006

ChemInform is a weekly Abstracting Service, delivering concise information at a glance that was extracted from about 200 leading journals. To access a ChemInform Abstract, please click on HTML or PDF.
Vanadium, Niobium and Tantalum
Authors: Love Jason B.
Published: July 2006

ChemInform is a weekly Abstracting Service, delivering concise information at a glance that was extracted from about 200 leading journals. To access a ChemInform Abstract, please click on HTML or PDF.
Nature of the Active Species in Palladium Catalyzed Mizoroki—Heck and Suzuki—Miyaura Couplings — Homogeneous or Heterogeneous Catalysis: A Critical Review
Authors: Phan Nam T. S. , Van Der Sluys Matthew , Jones Christopher W.
Published: July 2006

ChemInform is a weekly Abstracting Service, delivering concise information at a glance that was extracted from about 200 leading journals. To access a ChemInform Abstract, please click on HTML or PDF.
Synthesis of 4′‐N Pyrrolidine Nucleosides, Nucleotides, and Oligonucleotides
Authors: Rejman Dominik , Kocalka Petr , Pohl Radek , Rosenberg Ivan
Published: July 2006

ChemInform is a weekly Abstracting Service, delivering concise information at a glance that was extracted from about 200 leading journals. To access a ChemInform Abstract, please click on HTML or PDF.
Connecting Catalytic Cycles by Organometallic Transformations in situ: Novel Perspectives in Olefin Metathesis
Authors: Schmidt Bernd
Published: July 2006

ChemInform is a weekly Abstracting Service, delivering concise information at a glance that was extracted from about 200 leading journals. To access a ChemInform Abstract, please click on HTML or PDF.
Sulfenylphosphinoferrocenes: Novel Planar Chiral Ligands in Enantioselective Catalysis
Authors: Cabrera Silvia , Mancheno Olga Garcia , Arrayas Ramon Gomez , Alonso Ines , Mauleon Pablo , Carretero Juan C.
Published: July 2006

ChemInform is a weekly Abstracting Service, delivering concise information at a glance that was extracted from about 200 leading journals. To access a ChemInform Abstract, please click on HTML or PDF.
Charge Transfer Processes in Conducting Polymer Films
Authors: Malev V. V. , Kondratiev V. V.
Published: July 2006

ChemInform is a weekly Abstracting Service, delivering concise information at a glance that was extracted from about 200 leading journals. To access a ChemInform Abstract, please click on HTML or PDF.
Multisegmented One‐Dimensional Nanorods Prepared by Hard‐Template Synthetic Methods
Authors: Hurst Sarah J. , Payne Emma Kathryn , Qin Lidong , Mirkin Chad A.
Published: July 2006

ChemInform is a weekly Abstracting Service, delivering concise information at a glance that was extracted from about 200 leading journals. To access a ChemInform Abstract, please click on HTML or PDF.
Protein Folding Thermodynamics and Dynamics: Where Physics, Chemistry, and Biology Meet
Authors: Shakhnovich Eugene
Published: July 2006

ChemInform is a weekly Abstracting Service, delivering concise information at a glance that was extracted from about 200 leading journals. To access a ChemInform Abstract, please click on HTML or PDF.
Electrical spin injection into InGaAs quantum dots
Authors: Löffler W. , Tröndle D. , Fallert J. , Tsitsishvili E. , Kalt H. , Litvinov D. , Gerthsen D. , Lupaca‐Schomber J. , Passow T. , Daniel B. , Kvietkova J. , Hetterich M.
Published: July 2006

We report on the injection of electron spins into InGaAs quantum dots with an efficiency of up to 60%. This injection is observed in p‐i‐n light‐emitting diode structures using the diluted magnetic semiconductor ZnMnSe as spin aligner (spin‐LED). The degree of spin polarization is deduced from the circular polarization degree of the photons emitted when the injected electrons recombine in the quantum dots with unpolarized holes. We observe a strong energy dependence of the polarization degree with a strong increase starting from zero to a high value on the high energy side of the emission spectrum. To study the origin of this dependence, we compare results of two quantum‐dot samples with emission peaks at 1.2 eV and 1.33 eV, respectively. (© 2006 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)
Path integral Monte Carlo results for Bose condensation of mesoscopic indirect excitons
Authors: Filinov A. , Bonitz M. , Ludwig P. , Lozovik Yu. E.
Published: July 2006

First principle results for small clusters of strongly correlated indirect excitons in a harmonic confinement potential are presented. At low temperature Bose condensation is verified. The condensate fraction and the superfluid density are computed. The importance of a correct treatment of the Fermi statistics of electrons and holes is demonstrated. (© 2006 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)
Influence of the phonon‐exciton interaction on exciton‐exciton quantum correlation in semiconductor microcavities
Authors: Portolan S. , Di Stefano O. , Savasta S. , Rossi F.
Published: July 2006

We present an extension of the previous descriptions based on the Dynamics Controlled Truncation Scheme of light‐matter interaction beyond mean‐field, including the microscopic description of the exciton‐photon interaction. This enables the microscopic analysis of the influence of decoherence and noise on the polariton quantum correlations originating from nonlinear optical processes. We expand the operators involved in the dynamics in terms of exact eigenstates of the electron system, the photon and phonon operators and treat phonon‐assisted transitions within the Markov approximation. In particular, we present quantum Heisenberg‐Langevin equations describing light‐induced excitations in semiconductor systems interacting with the phonon bath. This theoretical framework is applied to study the influence of dephasing and noise due to photoluminescence on polariton quantum correlations generated by parametric emission in microcavities. (© 2006 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)
Transport in quantum devices: modelling contacts in the Wigner formalism
Authors: Taj D. , Genovese L. , Rossi F.
Published: July 2006

We shall discuss the role of the contacts as they are modelled in the conventional treatment of quantum devices based on the Wigner‐Function formalism. Our analysis will show that the artificial spatial separation between device active region and external reservoirs is intrinsically incompatible with the non‐local character of quantum mechanics. More specifically, by means of an exactly‐solvable semiconductor model, we shall show that the application of the usual Up‐Wind boundary scheme to the Wigner transport equation may produce highly non‐physical results, like boundary‐driven negative probability distributions. (© 2006 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)
Two‐photon coherent control of dark orthoexcitons in Cu2O
Authors: Yoshioka K. , Kuwata‐Gonokami M.
Published: July 2006

We investigate experimentally the two‐photon coherence exhibited by optically forbidden exciton states in the bulk semiconductor Cu2O. Two‐photon coherent control is achieved by using phase‐locked optical pulse pairs. Very long dephasing times and a fine energy splittings of the order of µ‐eV are observed. (© 2006 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)
Microscopically resolved resonant Rayleigh scattering from single excitons
Authors: Schwedt Daniel , Schwartz Rico , Stolz Heinrich , Reuter Dirk , Wieck Andreas
Published: July 2006

Strongly disordered GaAs/AlGaAs quantum wells (QW) have been excited resonantly with a narrow bandwidth cw laser which was scanned over the absorption profile of the QW. The secondary emission of the QW was investigated with microscopic resolution using either a CCD, examining the spatial distribution of the emission, or an imaging CCD spectrograph. The observed resonant emission was found to be very well isolated spectrally as well as spatially. From comparison with numerical model calculations it was found that spectrally sharp emission peaks clearly can be assigned to single excitons. However, spatially isolated emission spots do not prove strong localization of the emitting excitons. (© 2006 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)
Non‐radiative recombination of optical excitations in (GaIn)(NAs) quantum wells
Authors: Rubel O. , Baranovskii S. D. , Hantke K. , Rühle W. W. , Thomas P. , Volz K. , Stolz W.
Published: July 2006

We present results of experimental and theoretical studies of thermal quenching of the photoluminescence intensity in (GaIn)(NAs)/GaAs quantum wells after various postgrowth treatments. The experimental data are well described in the framework of a phenomenological model, if thermal emission of excitons out of localized states into delocalized states at the mobility edge prior to their non‐radiative recombination is taken into account. Comparison between theoretical results and experimental data yields such material parameters as the energy scale of the band tail and the relative concentrations of non‐radiative centers and traps. (© 2006 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)
Stimulated emission from ZnO nanorod arrays
Authors: Hauschild R. , Lange H. , Priller H. , Klingshirn C. , Kling R. , Waag A. , Fan H. J. , Zacharias M. , Kalt H.
Published: July 2006

We discuss the time‐resolved photoluminescence (PL) spectra of single ZnO nanorods taken at excitation fluences above and below the laser threshold. In the latter case, P‐band emission related to polariton‐polariton scattering is observed for certain rod geometries while stimulated emission occurs within the electron‐hole plasma band. We calculate the intensity distribution of low‐order waveguide modes as well as their energy dependence for given nanorod geometries to discuss their relevance with respect to nanorod lasing and polariton propagation. Additional finite‐element analysis confirms that a gold layer formed at the nanorod‐substrate interface under certain growth conditions leads to an enhancement of confinement within the resonator. (2006 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)
Energy spectrum of strongly correlated electrons and indirect excitons in quantum dots
Authors: Balzer K. , Nölle C. , Bonitz M. , Filinov A.
Published: July 2006

In the limit of strong correlations, we present a general description of finite electron and exciton systems in semiconductor quantum dots or quantum wells with external electrostatic confinement. We are able to analytically obtain the energy spectrum and wave functions which are constructed by exact diagonalization of the Hamiltonian in terms of the N ‐particle eigenmodes. (© 2006 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)
Genetic filtering and optimal sampling of Schistosoma mansoni populations
Authors: SORENSEN R. E. , RODRIGUES N. B. , OLIVEIRA G. , ROMANHA A. J. , MINCHELLA D. J.
Published: July 2006

Allelic variation in 6 microsatellite markers was compared between frozen Schistosoma mansoni eggs and laboratory-passaged worms originating from the same 5 fecal samples obtained from Brazilian residents. Based on allelic richness values, the number of alleles detected per locus did not differ between egg and worm DNA templates. However, our ability to score loci differed between these DNA templates, with worms providing more scored loci per individual than eggs. Differences also existed between the worms and eggs in the identity of the specific alleles that were detected. Additionally, we observed a reduction in homozygous genotypes among laboratory-passaged worms relative to the eggs. Allelic diversity curves were calculated by genotyping all worms from a representative host sample to determine the relationship between the number of alleles detected at a locus and the number of worms genotyped. Curves for the 5 residents' worm infrapopulations for each of the loci were very similar. The equation y=19·55×ln(x)+9·992 explained the association between sampling effort (x) and number of alleles detected (y) with an R2 of 0·775. In conclusion, egg DNA templates and allelic diversity curves can benefit efforts to discern the sociological, ecological and evolutionary forces impacting the genetic diversity and disease epidemiology of human schistosomes.
Redundancy and recombination in the Echinococcus AgB multigene family: is there any similarity with protozoan contingency genes?
Authors: HAAG K. L. , GOTTSTEIN B. , MÜLLER N. , SCHNORR A. , AYALA F. J.
Published: July 2006

Numerous genetic variants of the Echinococcus antigen B (AgB) are encountered within a single metacestode. This could be a reflection of gene redundancy or the result of a somatic hypermutation process. We evaluate the complexity of the AgB multigene family by characterizing the upstream promoter regions of the 4 already known genes (EgAgB1-EgAgB4) and evaluating their redundancy in the genome of 3 Echinococcus species (E. granulosus, E. ortleppi and E. multilocularis) using PCR-based approaches. We have ascertained that the number of AgB gene copies is quite variable, both within and between species. The most repetitive gene seems to be AgB3, of which there are more than 110 copies in E. ortleppi. For E. granulosus, we have cloned and characterized 10 distinct upstream promoter regions of AgB3 from a single metacestode. Our sequences suggest that AgB1 and AgB3 are involved in gene conversion. These results are discussed in light of the role of gene redundancy and recombination in parasite evasion mechanisms of host immunity, which at present are known for protozoan organisms, but virtually unknown for multicellular parasites.
On a model for the motion of a contact line on a smooth solid surface
Authors: BILLINGHAM J.
Published: July 2006

In this paper we investigate the model for the motion of a contact line over a smooth solid surface developed by Shikhmurzaev, [24]. We show that the formulation is incomplete as it stands, since the mathematical structure of the model indicates that an additional condition is required at the contact line. Recent work by Bedeaux, [4], provides this missing condition, and we examine the consequences of this for the relationship between the contact angle and contact line speed for Stokes flow, using asymptotic methods to investigate the case of small capillary number, and a boundary integral method to find the solution for general capillary number, which allows us to include the effect of viscous bending. We compare the theory with experimental data from a plunging tape experiment with water/glycerol mixtures of varying viscosities [11]. We find that we are able to obtain a reasonable fit using Shikhmurzaev's model, but that it remains unclear whether the linearized surface thermodynamics that underlies the theory provide an adequate description for the motion of a contact line.
Foundations of a robust social-ecological system: irrigation institutions in Taiwan
Authors: LAM WAI FUNG
Published: July 2006

The decline of agriculture in Taiwan has adversely affected the incentives of farmers and the government to engage in irrigation management. Despite that, Taiwan's irrigation systems have shown a high degree of robustness. This study seeks to understand how institutions have contributed to the robustness of Taiwanese irrigation. Conceptualizing an irrigation system as a social-ecological system (SES), this study examines the development and design of Taiwanese irrigation institutions, and how these institutions have enabled farmers and irrigation managers to cope with the dynamics in the SES, and hence contributed to the system's robustness.

The study has found that the robust systems are built upon institutions that allow effective coordination of the activities of a multitude of farmers, enhance the development and sustenance of a repertoire of ideas, and nest the problem-solving efforts of various scopes and scales in a complementary manner. The institutions enable individuals and organizations at different levels to engage in continuous learning and adaptation that, in turn, facilitates the systems' adaptation to the changing environment.
Diverse Functions and Molecular Properties Emerging for CAX Cation/H+ Exchangers in Plants
Authors: Shigaki T. , Hirschi K. D.
Published: July 2006

Abstract: Steep concentration gradients of many ions are actively maintained, with lower concentrations typically located in the cytosol, and higher concentrations in organelles and outside the cell. The vacuole is an important storage organelle for many ions. The concentration gradient of cations is established across the plant tonoplast, in part, by high‐capacity cation/H+ (CAX) exchange activity. While plants may not be green yeast, analysis of CAX regulation and substrate specificity has been greatly aided by utilizing yeast as an experimental tool. The basic CAX biology in Arabidopsis has immediate relevance toward understanding the functional interplay between diverse transport processes. The long‐range applied goals are to identify novel transporters and express them in crop plants in order to “mine” nutrients out of the soil and into plants. In doing so, this could boost the levels of essential nutrients in plants.
Earthquake Risk Analysis for Los Angeles County under Present and Planned Land Uses
Authors: Olshansky Robert B , Wu Yueming
Published: July 2006

Local governments rarely use risk analysis, the most sophisticated level of hazard assessment, to inform their planning and development decisions. But new tools are rapidly becoming available to accomplish such analysis. In this paper we present an example of an earthquake risk analysis for Los Angeles County, using available land-use maps, a probabilistic earthquake hazard model developed by the Southern California Earthquake Center, and the Federal Emergency Management Agency's new HAZUS earthquake loss estimation software. We computed the annual expected loss owing to earthquakes and the spatial variation of this risk. The analysis shows that the annual long-term earthquake risk in Los Angeles County, as a result of direct structural and nonstructural damage, is $388 million per year. We also investigated the extent to which planned future land-use growth would affect this risk estimate. We found that planned growth of 14.2% would result in an increase in annual risk to $449.5 million, a 15.8% increase over the risk to current land uses. Because of ever increasing disaster costs, planners need to be able to evaluate the risks that their communities face, both in the present and in the future. It is particularly important for planners to be sure that they are not disproportionately planning future growth for hazardous locations. In this paper we describe some ways in which to perform such evaluations, by using tools that have only recently become available.
An Initial Exploration of a Lacunarity-Based Segregation Measure
Authors: Wu X Ben , Sui Daniel Z
Published: July 2006

It has been recognized that urban residential segregation is a scale-dependent phenomenon, and yet all existing structural or spatial indices measure only certain dimensions of segregation at one single scale. Inspired by new metrics developed by landscape ecologists to measure landscape heterogeneity, in this paper we explore the feasiblity of a multiscale, lacunarity-based segregation measure. We also develop a straightforward GIS-based procedure to calculate this new measure. Our initial simulation results show that lacunarity is an effective measure that can capture multiple dimensions of segregation patterns at multiple scales.
Small is Beautiful: A Probit Analysis of Development Control of Small Houses in Hong Kong
Authors: Lai Lawrence W C , Ho Winky K O
Published: July 2006

In this paper we apply the probit model, an econometric technique that has been used in urban economics to examine nonaggregate cross-sectional data, to investigate the development control (planning application) data regarding the so-called ‘small houses’ in Hong Kong with respect to two classes of statutory zones, namely the ‘green belt’ and ‘unspecified uses’ zones. Four refutable hypotheses relating to the scale of the development, exogenous policies, and internal planning guidelines confronting the planning permission mechanism are tested by using a probit model adapted for the purpose. The data set with 826 individual observations over a period of 24 years from 1975 is part of the first systematically collected and unpublished planning statistics data set for Hong Kong. Although the hypotheses are specific to Hong Kong, they can be easily adapted, where nonaggregate planning statistics are available, to evaluate three general issues: rent seeking, the dependence of planning decisions on announced policies, and the spatial variation in success rates of planning applications.
Deregulation and Privatisation of European Building-Control Systems?
Authors: Meijer Frits , Visscher Henk
Published: July 2006

In this paper we describe the developments of European building regulatory systems and place them within the context of general trends in the regulatory sciences, particularly with reference to Europeanisation studies. Within the regulatory sciences there is broad consensus about the trend towards deregulation and privatisation in recent decades. Studies conducted under the rubric of ‘Europeanisation’ analyse the effects of European policies on the policy frameworks of the member states in more detail. Are the systems converging or diverging? Although the history of this kind of research is short, most authors agree that European policies have had a profound impact on the policies of the member states, but that this impact has not been uniform. In this paper, we analyse privatisation and deregulation trends within the building regulatory systems of eight European countries, and we consider whether the systems appear to be converging or diverging. We focus on three elements: the scope of the technical requirements, the building-permit procedures and the division of control and inspection responsibilities. The analyses reveal no evidence that the scope of technical requirements in European countries is diminishing. Through its directives, the European Union exercises a convergent influence on the contents, scope, and formulation of these technical requirements. In addition, all member countries are taking steps to streamline their administrative procedures. The importance of the role played by private organisations in checking and controlling regulations is increasing across the board. Although they differ in pace and emphasis, these administrative deregulation and privatisation trends exhibit a number of parallel developments.
Impact of Political Incidents, Financial Crises, and Severe Acute Respiratory Syndrome on Hong Kong Regulators and Developers
Authors: Lai Lawrence W C , Chau K W , Ho Daniel C W , Lin Veronica Y Y
Published: July 2006

We use two linear statistical techniques to examine the impact of the announcement of China's decision to take back Hong Kong from the United Kingdom in 1982, the Tiananmen Square incident of 4 June 1989, the Asian financial crisis of 1997, and the outbreak of severe acute respiratory syndrome in 2003 on Hong Kong's housing and land markets in terms of the decision patterns of the Town Planning Board (TPB), and the readiness of developers in applying to the Building Authority for ‘consent to commence work’. A total of 884 sets of all cross-sectional statistics about planning applications arising from Comprehensive Development Area zones from December 1980 to August 2004 were used to test four hypotheses that evaluate the impact of shocks on the TPB through the use of a parametric technique, probit modeling. A total of 96 sets of all aggregate statistics on developers' applications for ‘consent to commence work’ from 1982 to 2004 were used to test yet another four hypotheses that evaluate the impact of shocks on developers using a nonparametric technique, the Wilcoxon rank-sum test. The inferences based on the statistical findings of the two sets of hypotheses, which satisfy the relevant goodness-of-fit tests, are (a) that the TPB was sensitive and responsive to these shocks in making its decisions; and (b) that developers were not sensitive to any of the shocks in terms of their readiness to build.
Molecular and biochemical characterisation of polyphenol oxidases in developing kernels and senescing leaves of wheat (Triticum aestivum)
Authors: Jukanti Aravind K. , Bruckner Phil L. , Fischer Andreas M.
Published: July 2006

Polyphenol oxidases (PPOs) have been implicated in plant defence reactions. From an applied point of view, high PPO activity is associated with browning / darkening of fresh and processed food. Owing to its complex genome and economic importance, wheat (Triticum aestivum L.) represents an interesting system to advance our understanding of plant PPO function. We have previously shown that wheat PPOs are organised in a multigene family, consisting of two distinct phylogenetic clusters with three members each. In this study, we demonstrate that members of one cluster are not expressed in developing kernels or senescing flag leaves. Transcriptional regulation of one major gene in the other cluster largely controls PPO levels in these tissues, at least in the wheat varieties used for this study. Our data further indicate that the product of this gene is present as a latent enzyme during early kernel development, and that the latent enzyme is activated during later developmental phases. Enzyme activation can be achieved in vitro by limited tryptic digestion, but our data do not indicate activation by a proteolytic mechanism in vivo. Together, results presented in this study provide important insights into the regulation of wheat PPO function.
Transformation of cambial tissue in vivo provides an efficient means for induced somatic sector analysis and gene testing in stems of woody plant species
Authors: Van Beveren Kim S. , Spokevicius Antanas V. , Tibbits Josquin , Wang Qing , Bossinger Gerd
Published: July 2006

Large-scale functional analysis of genes and transgenes suspected to be involved in wood development in trees is hindered by long generation times, low transformation and regeneration efficiencies and difficulties with phenotypic assessment of traits, especially those that appear late in a tree’s development. To avoid such obstacles many researchers have turned to model plants such as Arabidopsis thaliana (L.) Heynh., Zinnia elegans Jacq. and Nicotiana ssp., or have focused their attention on in vitro wood formation systems or in vivo approaches targeting primary meristems for transformation. Complementing such efforts, we report the use of Agrobacterium to introduce transgenes directly into cambial cells of glasshouse-grown trees in order to create transgenic somatic tissue sectors. These sectors are suitable for phenotypic evaluation and analysis of target gene function. In our experiments the wood formation zone containing the cambium of Eucalyptus, Populus and Pinus species of varying age was inoculated with Agrobacterium containing a CaMV 35S::GUS construct. Following an initial wound response, frequent and stable transformation was observed in the form of distinct GUS-staining patterns (sectors) in newly formed secondary tissues. Sector size and extent depended on the cell type transformed, the species and the length of time treated plants were allowed to grow (more than two years in some cases). Induced somatic sector analysis (ISSA) can now be efficiently used to study cell fate and gene function during secondary growth in stems of forest tree species.
BMP action in skeletogenesis involves attenuation of retinoid signaling
Authors: Hoffman Lisa M. , Garcha Kamal , Karamboulas Konstantina , Cowan Matthew F. , Drysdale Linsay M. , Horton William A. , Underhill T. Michael
Published: July 2006

The bone morphogenetic protein (BMP) and growth and differentiation factor (GDF) signaling pathways have well-established and essential roles within the developing skeleton in coordinating the formation of cartilaginous anlagen. However, the identification of bona fide targets that underlie the action of these signaling molecules in chondrogenesis has remained elusive. We have identified the gene for the retinoic acid (RA) synthesis enzyme Aldh1a2 as a principal target of BMP signaling; prochondrogenic BMPs or GDFs lead to attenuation of Aldh1a2 expression and, consequently, to reduced activation of the retinoid signaling pathway. Consistent with this, antagonism of retinoid signaling phenocopies BMP4 action, whereas RA inhibits the chondrogenic stimulatory activity of BMP4. BMP4 also down-regulates Aldh1a2 expression in organ culture and, consistent with this, Aldh1a2 is actively excluded from the developing cartilage anlagens. Collectively, these findings provide novel insights into BMP action and demonstrate that BMP signaling governs the fate of prechondrogenic mesenchyme, at least in part, through regulation of retinoid signaling.
“Let There Be Bile”‐Understanding Hepatic Injury in Cholestasis
Authors: Sokol Ronald J. , Devereaux Michael , Dahl Rolf , Gumpricht Eric
Published: July 2006

Cholestatic liver disorders account for a large proportion of chronic liver ailments in adults, children and infants, and are among the leading indications for liver transplantation in all age groups. Recent studies have begun to characterize the cellular and molecular mechanisms of hepatocyte injury caused by the retention of hydrophobic bile acids in cholestasis. Steatocholestasis is the combined presence of hepatic steatosis and cholestasis, common in genetic causes of metabolic liver disease in childhood. Retention of hydrophobic bile acids promotes hepatocellular injury and subsequent portal fibrosis in these conditions. Investigations at the mechanistic level have revealed that activation of hepatocyte death receptors, induction of oxidative stress, mitochondrial perturbations and activation of caspases are intracellular pathways that mediate hepatocyte injury. Several compounds in licorice root have been shown to modulate bile acid‐induced apoptosis and necrosis of hepatocytes. Further investigations will be needed to identify novel molecular and cellular targets for which pharmaceuticals might be developed, to reduce liver injury and fibrosis in cholestasis and steatocholestasis.
Biochemical Abnormality in Erythropoietic Protoporphyria
Authors: Bloomer Joseph R. , Wang Yongming , Singhal Anuj , Risheg Hiba
Published: July 2006

Objectives:

Erythropoietic protoporphyria (EPP) is a genetic disorder in which deficient ferrochelatase (FECH) activity causes the excessive production and excretion of protoporphyrin. This in turn causes the major clinical manifestation of EPP, photosensitivity and, in some patients, hepatobiliary disease that may be severe. The objective of this study was to define genotypic determinants of phenotype in EPP.

Methods:

FECH activity was measured in 30 tissue samples from 26 patients with symptomatic EPP to determine the degree of deficient activity. FECH DNA analysis was also done in 26 families with EPP to identify mutations and examine for the presence of a polymorphism (IVS3‐48c) that causes low gene expression.

Results:

The level of residual FECH activity that was measured in tissue samples of patients with symptomatic EPP was ≤30% of the mean normal level in all patients except one. Lowest levels (4‐20% normal) were in patients with advanced EPP liver disease. Heterozygous FECH mutations were found in 45 individuals from 26 families with EPP. In 94% of the 32 symptomatic individuals, 15 of whom had liver disease, the polymorphism was present in the nonmutant allele. In 13 asymptomatic patients, the polymorphism was absent.

Conclusions:

Patients with symptomatic EPP (photosensitivity with/without hepatobiliary disease) usually have a mutation in 1 FECH allele that alters enzyme structure/function, together with a polymorphism in the nonmutant allele that causes low gene expression. This leads to a significant reduction in FECH activity that causes symptomatic disease to develop because of the excess protoporphyrin produced.
Liver Disease in Cystic Fibrosis
Authors: Colombo Carla , Russo Maria Chiara , Zazzeron Laura , Romano Giovanna
Published: July 2006

Liver involvement in Cystic Fibrosis (CF) is much less frequent than both pulmonary and pancreatic diseases that are present in 80‐90% of CF patients; liver disease (LD) affects only one third of CF patients, however, because of the decreasing mortality from extrahepatic causes, its recognition and management is becoming a relevant clinical issue. Recent observations suggest that clinical expression of LD in CF may be influenced by genetic modifiers; their identification is an important issue because it may allow recognition of patients at risk for the development of LD at the time of diagnosis of CF and early institution of prophylactic strategies. Oral bile acid therapy, aimed at improving biliary secretion in terms of bile viscosity and bile acid composition, is currently the only available therapeutic approach for CF‐associated LD. However, the impact of this therapy on the natural history of LD remains to be defined and long‐term effectiveness on clinically relevant outcomes should be further investigated. Liver transplantation should be offered to CF patients with progressive liver failure and/or with life‐threatening sequelae of portal hypertension, who also have mild pulmonary involvement that is expected to support long‐term survival. The 1‐year survival rate after transplantation in CF patients is approximately 80%, with beneficial effects on lung function, nutritional status, body composition and quality of life in most cases.