bluuebunny/crossref_metadata_2025 huggingface dataset:
Modelling hourly and daily open‐water evaporation rates in areas with an equatorial climate
Authors: Tan Stephen Boon Kean , Shuy Eng Ban , Chua Lloyd Hock Chye
Published: August 2006

Evaporation rate estimation is important for water resource studies. Previous studies have shown that the radiation‐based models, mass transfer models, temperature‐based models and artificial neural network (ANN) models generally perform well for areas with a temperate climate. This study evaluates the applicability of these models in estimating hourly and daily evaporation rates for an area with an equatorial climate. Unlike in temperate regions, solar radiation was found to correlate best with pan evaporation on both the hourly and daily time‐scales. Relative humidity becomes a significant factor on a daily time‐scale. Among the simplified models, only the radiation‐based models were found to be applicable for modelling the hourly and daily evaporations. ANN models are generally more accurate than the simplified models if an appropriate network architecture is selected and a sufficient number of data points are used for training the network. ANN modelling becomes more relevant when both the energy‐ and aerodynamics‐driven mechanisms dominate, as the radiation and the mass transfer models are incapable of producing reliable evaporation estimates under this circumstance. Copyright © 2006 John Wiley & Sons, Ltd.
Hydroclimatic teleconnection between global sea surface temperature and rainfall over India at subdivisional monthly scale
Authors: Maity Rajib , Kumar D. Nagesh
Published: August 2006

It is well established that sea surface temperature (SST) plays a significant role in the hydrologic cycle in which precipitation is the most important part. In this study, the influence of SST on Indian subdivisional monthly rainfall is investigated. Both spatial and temporal influences are investigated. The most influencing regions of sea surface are identified for different subdivisions and for different overlapping seasons in the year. The relative importance of SST, land surface temperature (LST) and ocean–land temperature contrast (OLTC) and their variation from subdivision to subdivision and from season to season are also studied. It is observed that LST does not show much similarity with rainfall series, but, in general, OLTC shows relatively higher influence in the pre‐monsoon and early monsoon periods, whereas SST plays a more important role in late‐ and post‐monsoon periods. The influence of OLTC is seen to be mostly confined to the Indian Ocean region, whereas the effect of SST indicates the climatic teleconnection between Indian regional rainfall and climate indices in Pacific and Atlantic Oceans. Copyright © 2006 John Wiley & Sons, Ltd.
The distributive consequences of machismo: a simulation analysis of intra‐household discrimination
Authors: Cuesta José
Published: August 2006

Empirical evidence questions the unitary allocation model of the household that underpins the standard measurement of monetary poverty and inequality. Intra‐household gender discrimination has been widely shown to shape expenditure decisions, nutrition status, and human capital accumulation of household members. However, conventional poverty and inequality analyses are conducted for the household as a whole, which might lead to different conclusions compared with studies based on individuals. Using recent developments in intra‐household bargaining modelling, this paper constructs non‐cooperative allocation rules dominated by gender discrimination among household members. Estimates for Chile show a substantial worsening of poverty and inequality under such allocation rules. This suggests that intra‐household discrimination deserves some of the attention typically directed to extra‐household discrimination in labour markets, access to public services or political participation. Copyright © 2006 John Wiley & Sons, Ltd.
Models of Irregular Hyperbranched Polymers: Topological Disorder and Mechanical Response
Authors: Koslowski Thorsten , Jurjiu Aurel , Blumen Alexander
Published: August 2006

Summary: We study the impact of topological disorder on the mechanical response of hyperbranched macromolecules from a theoretical and numerical perspective. The polymer models are generated using a bond switching algorithm, and the emerging systems are described within the Zimm and Rouse pictures of macromolecular dynamics. The topological disorder is manifest in the frequency‐dependent dynamic moduli, $G^*(\omega)$. These are clearly distinct from that of regular hyperbranched fractals of the same size, and they do not obey simple scaling rules. The dynamic moduli reflect the short‐range order inherent in the model, and we thus suggest that the extent of disorder in branched tree‐like polymers may be well‐estimated experimentally using $G^*(\omega)$.

Model of an irregular hyperbranched polymer.

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Model of an irregular hyperbranched polymer.
Vulnerable options in supply chains: Effects of supplier competition
Authors: Babich Volodymyr
Published: August 2006

Concerned with the risk of supplier default, a firm may choose to diversify its orders among multiple suppliers. Furthermore, the discrepancy in production lead‐times among suppliers furnishes a firm with a valuable option to defer ordering decisions until uncertainty has been partially resolved. The suppliers also have an option: to defer their pricing decisions. Using a single‐period, multi‐stage model of a two‐echelon supply chain with competing risky suppliers and a single manufacturer, this paper investigates how the supplier default risk and default co‐dependence affect manufacturer procurement and production decisions, supplier pricing decisions, firms profits, and the deferment option value and how the introduction of the deferment option alters supplier competition. © 2006 Wiley Periodicals, Inc. Naval Research Logistics 2006
Topology optimization of material‐nonlinear continuum structures by the element connectivity parameterization
Authors: Yoon Gil Ho , Kim Yoon Young
Published: August 2006

The application of the element density‐based topology optimization method to nonlinear continuum structures is limited to relatively simple problems such as bilinear elastoplastic material problems. Furthermore, it is very difficult to use analytic sensitivity when a commercial nonlinear finite element code is used. As an alternative to the element density formulation, the element connectivity parameterization (ECP) formulation is developed for the topology optimization of isotropic‐hardening elastoplastic or hyperelastic continua by using commercial software. ECP varies the stiffness of zero‐length linear elastic links that connect design domain‐discretizing finite elements. Unloading was not considered. But the advantages of ECP in material‐nonlinear problems were demonstrated: considerably simple analytic sensitivity calculation using a commercial code and simple link stiffness penalization regardless of nonlinear material behaviour. Copyright © 2006 John Wiley & Sons, Ltd.
A strategy for input estimation with sensitivity analysis
Authors: Nordström Lars J. L. , Johansson Håkan , Larsson Fredrik
Published: August 2006

The estimation of unknown excitation or input signals from measured response is essentially the solution of an optimization problem; a function representing the input is sought such that the discrepancy between measured and simulated response is minimized. From the view of optimization it is convenient to consider the general situation where the governing differential equations may be time‐variant and non‐linear. Moreover, the choice of parameterization for the sought input, sampling instances of measurement data and discretization of the state problem are all decoupled, in contrast to standard methods such as Dynamic Programming.

In this paper, the optimization problem is solved by seeking a stationary point of the pertinent Lagrangian functional, resulting in a Newton‐type iterative algorithm. Moreover, the sensitivity of the solution with respect to measurement noise may also be estimated from a perturbation analysis of the optimality conditions. Two numerical examples show that the approach produces results in agreement with those of standard methods, however, with the additional advantage the numerical properties of the considered problem may be investigated. In particular, such knowledge may be used for choosing a proper amount of regularization. Copyright © 2006 John Wiley & Sons, Ltd.
Two possible cases of brucellosis from a Clarist monastery in Alcácer do Sal, southern Portugal
Authors: Curate F.
Published: August 2006

The Convent of Nossa Senhora de Aracoelli was a Clarist monastery located in Alcácer do Sal, southern Portugal, founded at the end of the 16th century and abandoned during the 19th century. This paper considers the presence of brucellosis in two lumbar vertebrae originating from an ossuary recovered at the Chapter House of the Convent. Copyright © 2006 John Wiley & Sons, Ltd.
A palaeopathological study of Colles' fracture
Authors: Mays S. A.
Published: August 2006

This work is an osteological study of four cases of Colles' fracture from a 3rd–4th century AD British archaeological site. Each case was from an elderly female. Investigation of the degree of malunion suggests lack of effective reduction for these fractures. The poor anatomical outcome appears generally to have resulted in poor functional outcome; detailed anatomical study provided evidence for impairment of function of the distal radioulnar joint, ulnocarpal abutment and scapholunate diastasis, conditions which would probably have caused long‐term residual disability. Copyright © 2006 John Wiley & Sons, Ltd.
Complete discrepancy between abnormal fetal karyotypes predicted by QF‐PCR rapid testing and karyotyped cultured cells in a first‐trimester CVS
Authors: Waters Jonathan J. , Walsh Sally , Levett Lisa J. , Liddle Stuart , Akinfenwa Yinka
Published: August 2006

A chorion villus sample (CVS) biopsied at 11 weeks' gestation for raised nuchal translucency, revealed monosomy X (presumptive 45,X karyotype) by QF‐PCR for rapid aneuploidy testing for chromosomes 13, 18, 21, X and Y. Long‐term culture gave the karyotype: 47,XY,+ 21[66]/49,XYY,+ 21,+ 21 [22]. This discrepancy prompted redigestion of the combined residual villus fragments from the original QF‐PCR assay. The repeat QF‐PCR assay identified the presence of trisomy 21 and a Y chromosome consistent with a 47,XY,+ 21 karyotype. A double non‐disjunction event early in embryogenesis in a 47,XY,+ 21 conceptus with subsequent cell lineage compartmentalisation of the three observed cell lines (45,X; 47,XY,+ 21 and 49,XYY,+ 21,+ 21) would account for these results. This is the first reported case to describe complete discrepancy at diagnosis between abnormal karyotypes detected by QF‐PCR rapid aneuploidy testing and a cultured karyotype in the same CVS. Copyright © 2006 John Wiley & Sons, Ltd.
Non‐mosaic trisomy 22: a report of 2 cases
Authors: Mokate T. , Leask K. , Mehta S. , Sharif S. , Smith A. , Saxena A. , Mahmood T.
Published: August 2006

Non‐mosaic trisomy 22 is a common cause of first trimester miscarriage and has a livebirth incidence of 1 in 30 000–50 000. Consequently there is a paucity of information for counselling parents. Detection in the second trimester is rare. It is commonly associated with severe growth retardation and multiple structural abnormalities. Oligohydramnios is frequently seen and can make detection of other abnormalities difficult. The outlook is uniformly poor and survival beyond the first trimester may present management dilemmas. A thorough fetal assessment including high‐resolution cytogenetics with or without FISH is required for counselling. Careful plans for intrapartum and neonatal management may be necessary. The recurrence risk is thought to be low but information is very limited as there have been no reported cases of recurrence. We present two case of non‐mosaic trisomy 22 including the first to be diagnosed subsequent to investigation for a high serum screening Down's risk. Copyright © 2006 John Wiley & Sons, Ltd.
Functional annotation of proteins identified in human brain during the HUPO Brain Proteome Project pilot study
Authors: Mueller Michael , Martens Lennart , Reidegeld Kai A. , Hamacher Michael , Stephan Christian , Blüggel Martin , Körting Gerhard , Chamrad Daniel , Scheer Christian , Marcus Katrin , Meyer Helmut E. , Apweiler Rolf
Published: August 2006

The HUPO Brain Proteome Project is an initiative coordinating proteomics studies to characterise human and mouse brain proteomes. Proteins identified in human brain samples during the project's pilot phase were put into biological context through integration with various annotation sources followed by a bioinformatics analysis. The data set was related to the genome sequence via the genes encoding identified proteins including an assessment of splice variant identification as well as an analysis of tissue specificity of the respective transcripts. Proteins were furthermore categorised according to subcellular localisation, molecular function and biological process, grouped into protein families and mapped to biological pathways they are known to act in. Involvement in pathological conditions was examined based on association with entries in the online version of Mendelian Inheritance in Man and an interaction network was derived from curated protein‐proteininteraction data. Overall a non‐redundant set of 1804 proteins was identified in human brain samples. In the majority of cases splice variants could be unambiguously identified by unique peptides, including matches to several hypothetical transcripts of known as well as predicted genes.
Inductive effect of uncharged groups: dependence on electronegativity
Authors: Exner Otto , Böhm Stanislav
Published: August 2006

Substituent effects in rigid non‐conjugated systems were followed on the series of 3‐substituted 1‐fluoro‐bicyclo[1.1.1]pentanes and 2‐substituted 1‐fluoroethanes in the fixed ap conformation. Their energies were calculated within the framework of the density functional theory at the B3LYP/6‐311++G(3df,3pd)//B3LYP/6‐311++G(3df,3pd) level and the substituent effects were expressed in terms of isodesmic homodesmotic reactions. The results were confirmed by the energies of 1,4‐disubstituted bicyclo[2.2.2]octanes reported in the literature and calculated at a lower level. Interaction of two common substituents of low or medium polarity cannot be described as the classical inductive effect by one term, proportional in all series, but an additional parameter is necessary, which depends only on the first atom of the substituent and may be identified with its electronegativity. The second term decreases with the distance more steeply than the first term and is always much less important. Nevertheless its statistical significance was proved by several sensitive tests at the highest level used in statistics. When one of the substituents is charged (or at least strongly polar as NO2 or CN), the first term is much increased and the second becomes less significant or insignificant. Therefore, the standard definition of the inductive effect with a uniform, universally valid constant can be retained as far as one treats only the ionization equilibria, both in solution and in the gas phase, or kinetics with a strongly polar transition state.

In contrast to the firm statistical proofs, the physical meaning of the electronegativity term was not established. Any relation to various group electronegativities does not exist, similarity to the 13C NMR shifts is merely qualitative. Copyright © 2006 John Wiley & Sons, Ltd.
Photochromism of dihydroindolizines Part VI: synthesis and photochromic behavior of a novel type of IR‐absorbing photochromic compounds based on highly conjugated dihydroindolizines
Authors: Ahmed Saleh Abdel
Published: August 2006

Novel photochromic bis‐styryl dihydroindolizines (DHIs) 5a‐β bearing different cycloalkanone ring sizes were prepared in 11–42% yield via nucleophilic addition of bis‐styryl cycloalkanones 2a–k to substituted spirocyclopropenes 1a–g. The absorption maxima (λmax) of the colored betaines 4a‐β (formed after UV‐irradiation) were detected by millisecond flash photolysis, laser flash photolysis as well as FT‐UV/VIS measurements. All betaines 4a‐β showed two absorption maxima, one in the visible region (500–575 nm) and another one in the IR‐region (800–878 nm). The kinetics of the fast cyclizing process of betaines 4a‐β to DHIs 5a‐β were studied in dichloromethane solution by millisecond flash photolysis and were found to take place in the millisecond range (76–450 msec). The strong colorability of betaines 4a‐β may be attributed to the highly conjugated betaine structures as well as to the presence of the carbonyl chromophore. Interestingly, a remarkable photo‐fatigue resistance of some studied betaines 4 showed t30‐values higher than the standard one. Large solvatochromic effects on the absorption maxima (λmax) as well as a substantial increase of the half‐lives (t1/2) with solvent polarity of betaines 3a‐β were also observed. Copyright © 2006 John Wiley & Sons, Ltd.
An integrated approach to the study of intramolecular hydrogen bonds in malonaldehyde enol derivatives and naphthazarin: trend in energetic versus geometrical consequences
Authors: Musin Ryza N. , Mariam Yitbarek H.
Published: August 2006

Density functional and atoms‐in‐molecules (AIM) and natural bond orbital (NBO) approaches have been applied in the study of energetic (E), geometrical (G) and electronic (AIM and NBO) consequences of H bonding in malonaldehyde (MAE) derivatives and naphthazarin (NZ). AIM parameters and other measures of HB strength were used: (a) for the verification of (i) the reliability of the O···O distance (G consequence) as an indicator of IMHB strength; (ii) the capacity of the classically computed energetic parameters (ΔESEs) to serve as acceptable measures of IMHB strength; and (b) for the separation of the ΔESEs into (i) stabilization (HB) energies (EHSEs) that serve as apparent IMHB energies (EHB,As), and (ii) stabilization (isomerization) energies (ENSEs) that do not (owing to intractable contributions that are not germane to the solitary HB donor(D)‐acceptor(A) interactions). Some of the sources of the anomalies have been rationalized. AIM topological properties were used to study the nature of the IMHB interactions. An exponential parametric model for the correlation of EHSE with the O···O distance, which has asymptotic characteristics at long O···O distances, was obtained. The model (a) has predictive ability, that is, can be used to estimate, in an empirical manner, EHB,As that are otherwise grossly underestimated, and (b) can treat both the MAE derivatives and the NZ systems even though they possess very different resonant spacers connecting the HB D‐A segments. MAE and NZ are also demonstrated to have essentially the same IMHB strength. By contrast, a quadratic model for EHSE‐HB distance correlation was found to be unphysical. Use of electronic consequences of H bonding was shown to be essential for study of IMHBs with intractable interactions. Thus, AIM energy density and NBO second‐order interaction energy parameters were used for the verification of predictions of IMHB strengths made on the bases of energetic and geometrical consequences. Copyright © 2006 John Wiley & Sons, Ltd.
A prospective study of the impact of genetic susceptibility testing for BRCA1/2 or HNPCC on family relationships
Authors: Oostrom Iris van , Meijers‐Heijboer Hanne , Duivenvoorden Hugo J. , Bröcker‐Vriends Annette H. J. T. , van Asperen Christi J. , Sijmons Rolf H. , Seynaeve Caroline , Van Gool Arthur R. , Klijn Jan G. M. , Riedijk Samantha R. , van Dooren Silvia , Tibben Aad
Published: August 2006

This study assessed the impact of genetic testing for cancer susceptibility on family relationships and determinants of adverse consequences for family relationships. Applicants for genetic testing of a known familial pathogenic mutation in BRCA1/2 or a HNPCC related gene (N=271) rated the prevalence and nature of changes in family relationships, familial difficulties and conflicts due to genetic testing 6 months after receiving the test result. The level of family functioning, differentiation from parents, support and familial communication style regarding hereditary cancer were assessed before receiving the test result. Genetic testing affected some family relationships in a positive way (37%), i.e. by feeling closer, improved communication and support, more appreciation of the relative and relief of negative test result. A minority reported unwanted changes in relationships (19%), problematic situations (13%) or conflicts (4%). Adverse effects comprised feelings of guilt towards children and carrier siblings, imposed secrecy and communication problems. Predictors of adverse consequences on family relationships were reluctance to communicate about hereditary cancer with relatives and disengaged‐rigid or enmeshed‐chaotic family functioning. Open communication between relatives should be stimulated because a lack of open communication may be an important determinant of familial adverse effects. Copyright © 2006 John Wiley & Sons, Ltd.
A family‐based model to predict fear of recurrence for cancer survivors and their caregivers
Authors: Mellon Suzanne , Kershaw Trace S. , Northouse Laurel L. , Freeman‐Gibb Laurie
Published: August 2006

Although fear of cancer recurrence is a great concern among survivors and their families, few studies have examined predictors of fear of recurrence. The purpose of this study was to identify factors associated with fear of recurrence in a population‐based sample (N = 246) and determine if survivors and family caregivers influenced one another's fear of recurrence. A family framework guided the study and analyses included multilevel modeling using the Actor‐Partner Interdependence Model. Results indicated that survivors and family caregivers influenced each other's fear of recurrence and that caregivers had significantly more fear of recurrence than survivors. More family stressors, less positive meaning of the illness, and age were related to elevated fear of cancer recurrence for both survivors and caregivers. Copyright © 2006 John Wiley & Sons, Ltd.
Conformational flexibility of RecA protein filament: Transitions between compressed and stretched states
Authors: Petukhov Michael , Lebedev Dmitry , Shalguev Valery , Islamov Akhmed , Kuklin Aleksandr , Lanzov Vladislav , Isaev‐Ivanov Vladimir
Published: August 2006

RecA protein is a central enzyme in homologous DNA recombination, repair and other forms of DNA metabolism in bacteria. It functions as a flexible helix‐shaped filament bound on stretched single‐stranded or double‐stranded DNA in the presence of ATP. In this work, we present an atomic level model for conformational transitions of the RecA filament. The model describes small movements of the RecA N‐terminal domain due to coordinated rotation of main chain dihedral angles of two amino acid residues (Psi/Lys23 and Phi/Gly24), while maintaining unchanged the RecA intersubunit interface. The model is able to reproduce a wide range of observed helix pitches in transitions between compressed and stretched conformations of the RecA filament. Predictions of the model are in agreement with Small Angle Neutron Scattering (SANS) measurements of the filament helix pitch in RecA::ADP‐AlF4 complex at various salt concentrations. Proteins 2006. © 2006 Wiley‐Liss, Inc.
Spin dynamics and hyperfine interaction in InAs semiconductor quantum dots
Authors: Eble B. , Braun P.‐F. , Krebs O. , Lombez L. , Marie X. , Urbaszek B. , Amand T. , Lagarde D. , Renucci P. , Voisin P. , Lemaître A. , Kowalik K. , Kudelski A. , Kalevich V.K. , Kavokin K. V.
Published: August 2006

We present a detailed study of the hyperfine interaction between carrier and nuclear spins in InAs semiconductor quantum dots. Time resolved measurements on excitons in positively charged quantum dots show the electron spin relaxation due to random fluctuations of the spin orientation of the nuclei in the quantum dot. A complimentary aspect of the hyperfine interaction can be uncovered in single dot continuous wave photoluminescence experiments in a weak magnetic field, namely the Overhauser shift due to the dynamic polarisation of the nuclei following excitation with circularly polarised light. (© 2006 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)
Exciton‐spin relaxation in weakly confining quantum dots due to spin–orbit interaction
Authors: Tsitsishvili E. , Kalt H. , v. Baltz R.
Published: August 2006

In weakly confining quantum structures such as interfacial islands or quantum disks the exciton‐spin relaxation is governed by two independent electron and hole spin flip processes between the optically active and dark states. A microscopic theory for these transitions is presented which is based on second order spin–orbit and carrier–phonon interaction processes. We found that the sequential relaxation between bright and dark states leads to much faster exciton‐spin relaxation than for strongly confining (“small”) quantum dots where the dominant process stems from electron–hole exchange interaction plus hole deformation potential coupling. In addition, the fast exciton spin relaxation implies that the (exciton‐bound) electron spin flip time is also much shorter than for a single electron. (© 2006 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)
Strong and weak coupling of single quantum dot excitons in pillar microcavities
Authors: Reitzenstein S. , Hofmann C. , Löffler A. , Kubanek A. , Reithmaier J.‐P. , Kamp M. , Kulakovskii V. D. , Keldysh L. V. , Reinecke T. L. , Forchel A.
Published: August 2006

We report on strong as well as weak coupling of self assembled In0.30Ga0.70As quantum dots (QDs) in high‐Q semiconductor micropillar cavities grown by molecular beam epitaxy. Using electron beam lithography and deep plasma etching, micropillars with high Q‐factors (about 10000 for 1.6 µm diameter) were realized. The low QD density in the present structures allows us to investigate the interaction of single QD excitons and the vacuum field of the microcavity by temperature tuning of exciton lines into resonance with the cavity mode. We will present an example where QD excitons with different emission energies show strong or weak coupling with the optical mode of the same micropillar at different resonance temperatures. Here, the individual coupling behaviour is described in terms of a different spatial position of the QDs relative to the field maximum of the cavity mode. (© 2006 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)
Spin Coulomb drag: an intrinsic dissipation mechanism in spintronics
Authors: D'Amico I. , Ullrich C. A.
Published: August 2006

Spin Coulomb drag (SCD) plays an important role in spintronics as an intrinsic source of dissipation for spin currents in metals and semiconductors. We discuss two aspects of SCD and their practical relevance: the power loss in a generic spintronics device, and the damping of collective spin‐density excitations in semiconductor quantum wells. A purely optical quantitative measurement of the SCD effect is suggested. (© 2006 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)
Ramsey fringes in a single InGaAs/GaAs quantum dot
Authors: Ester P. , Stufler S. , de Michaelis Vasconcellos S. , Bichler M. , Zrenner A.
Published: August 2006

We report the observation of Ramsey fringes in single InGaAs/GaAs quantum dots. With double pulse p/2 excitation it is possible to control the occupancy and the phase of a quantum dot. The occupancy of the quantum dot oscillates with detuning. These Ramsey fringes are caused by a voltage dependent detuning of the QD. Due to the double pulse excitation the spectral sensitivity is strongly enhanced as compared to single pulse experiments. At long delay times we are able to resolve extremely narrow spectral fringes, clearly below the homogeneous linewidth of the underlying QD two level system. Our results demonstrate precision measurements on single quantum dots with strong implications for future quantum gates and quantum measurements. (© 2006 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)
Nonlinear optical response and exciton dephasing in quantum dots
Authors: Muljarov E. A. , Zimmermann R.
Published: August 2006

The full time‐dependent four‐wave mixing polarization in quantum dots is microscopically calculated, taking into account acoustic phonon‐assisted transitions between different exciton states of the dot. It is shown that quite different dephasing times of higher exciton states in pancake anisotropic InGaAs quantum dots are responsible for the experimentally observed [1] double‐exponential decay in the photon echo signal. (© 2006 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)
Theory of quantum dot luminescence from acoustically excited intersubband transitions
Authors: Milde F. , Ahn K. J. , Knorr A.
Published: August 2006

In this paper a theory of acoustically driven intersubband transitions in semiconductor quantum dots is developed. Well off‐resonant acoustic excitation leads to subsequently emitted THz radiation. (© 2006 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)
Dynamical T‐matrix theory for high‐density excitons in coupled quantum wells
Authors: Zimmermann R.
Published: August 2006

Excitons in coupled quantum wells open the possibility to reach high densities close to equilibrium. In a recent experiment employing a lateral trap potential, a blue shift and a broadening of the exciton emission line has been seen [D. W. Snoke et al., Solid State Commun. 134, 37 (2005)]. The standard Hartree–Fock treatment can explain the blue shift but fails to give a finite broadening. Starting from the (spin‐dependent) many‐exciton Hamiltonian with direct and exchange potential, we present a dynamical T‐matrix calculation for the single‐exciton Green's function which is directly related to the frequency‐ and angle‐resolved photoluminescence. The calculated spectrum is blue shifted and broadened due to exciton–exciton scattering. At high excitation, both the spectrum and the angular emission are getting narrow. This is a direct manifestation for off‐diagonal long range order and a precursor of condensation. (© 2006 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)
Collective excitation kinetics in the condensation of polaritons
Authors: Sarchi Davide , Savona Vincenzo
Published: August 2006

We develop a kinetic model for polariton condensation, in which the field dynamics of collective excitations is treated self‐consistently during the condensation kinetics. This model allows to account properly for the quantum fluctuations of the condensate. Using realistic parameters, we prove that long‐wavelength excitations considerably deplete the condensate just above threshold. (© 2006 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)
Preventive effects of Azadirachta indica on benzo(a)pyrene‐DNA adduct formation in murine forestomach and hepatic tissues
Authors: Gangar Subhash Chander , Sandhir Rajat , Rai Durg Vijay , Koul Ashwani
Published: August 2006

In the present investigation, the effects of aqueous Azadirachta indica leaf extract (AAILE) on 3H‐benzo(a)pyrene‐DNA [3H‐B(a)P‐DNA] adduct formation, the status of biotransformation enzymes and reduced glutathione (GSH) content were evaluated in the forestomach and liver of Balb/c mice. Two weeks of AAILE treatment reduced the 3H‐B(a)P‐DNA adduct levels by 31.6% in forestomach tissue. Similarly, 3H‐B(a)P‐DNA adduct levels were decreased by 34.7% in the liver of AAILE treated mice compared with their control counterparts. After AAILE treatment, the cytochrome P450 content decreased, whereas the GSH content increased significantly in the hepatic tissue. In the forestomach as well as in the liver, the cytochrome b5 content declined, whereas an increase in glutathione‐S‐transferase (GST) activity was observed in both tissues. These observations suggested that AAILE may have reduced the metabolic activation of 3H‐B(a)P with enhanced detoxification of its active metabolites, hence the observed decrease in the levels of 3H‐B(a)P‐DNA adducts. These molecular and biochemical modulations observed at the initiation phase of carcinogenesis seems to be significant and could be correlated with the chemopreventive effects of A. indica against B(a)P induced forestomach tumorigenesis. Copyright © 2006 John Wiley & Sons, Ltd.
Antiplasmodial activity of Homalium letestui
Authors: Okokon Jude E. , Ita Basil , Udokpoh Aniekan E.
Published: August 2006

The in vivo antiplasmodial activity of the ethanol root extract of Homalium letestui used as a malaria remedy in Southern Nigeria was evaluated in Plasmodium berghei berghei infected mice. Homalium letestui root extract (500–1000 mg/kg/day) exhibited significant (p < 0.05) blood schizontocidal activities both in a 4‐day early infection test and in an established infection with a considerable mean survival time comparable to that of the standard drug, chloroquine, 5 mg/kg/day. The root extract possesses significant (p < 0.05) antiplasmodial activity, which can be exploited in malaria therapy. Copyright © 2006 John Wiley & Sons, Ltd.
Correlation between the In Vitro antioxidant activity and polyphenol content of aqueous extracts from bulgarian herbs
Authors: Kiselova Yoana , Ivanova Diana , Chervenkov Trifon , Gerova Daniela , Galunska Bistra , Yankova Tatyana
Published: August 2006

The water phase antioxidant activity of extracts from 23 Bulgarian medicinal plants was studied in relation to their polyphenol content in comparison with mate, black tea, honeybush and rooibos foreign species. Antioxidant activity was measured by the ABTS (2,2′‐azinobis(3‐ethylbenzothiazoline‐6‐sulfonic acid)) cation radical decolorization assay, and the total polyphenol content was assayed according to the Folin‐Ciocalteu method. Five Bulgarian plant extracts exhibited higher antioxidant activity than that of mate, which is 21.7% of all Bulgarian herbs included in this study. These were Alchemilla vulgaris L. (4.79 ± 0.14 mm), Sambucus ebulus L. (4.03 ± 0.07 mm), Mentha spicata L. (3.90 ± 0.03 mm), Fragaria vesca L. (3.74 ± 0.06 mm), Crataegus monogyna Jacq. (3.63 ± 0.05 mm). Another eight Bulgarian medicinal plant extracts exhibited an intermediate antioxidant activity – lower than that of mate and higher than that of honeybush, which makes 34.8% of all Bulgarian herbs included in the study. More than half of the herbal extracts included in the present study exhibited antioxidant activity higher than or comparable to the reference foreign plants. A positive correlation (r = 0.92) between antioxidant activity and polyphenol content was found, suggesting that the antioxidant capacity of the aqueous plant extracts is due to a great extent to their polyphenols. Copyright © 2006 John Wiley & Sons, Ltd.
Miconazole gel compared with Zataria multiflora Boiss. gel in the treatment of denture stomatitis
Authors: Amanlou Massoud , Beitollahi Jalil Momen , Abdollahzadeh Shervin , Tohidast‐Ekrad Zahra
Published: August 2006

An open, randomized, controlled study with two parallel treatment groups was done to evaluate the efficacy of a miconazole 2% gel compared with Zataria multiflora 0.1% gel applied four times daily for 2 weeks, in the treatment of Candida‐associated denture stomatitis. Twenty four patients were included in the study. The efficacy variables were the colony count of Candida from the palatal mucosa and the denture surface and the erythema surface of the palatal mucosa on days 0, 7, 14, 21 and 28 after commencement of therapy. Twelve patients received miconazole gel and twelve Z. multiflora gel. The erythema surface was significantly reduced by both gels. No significant difference was seen between the two groups (p < 0.05). There was a significant reduction in the colony count of the palatal mucosa in both groups (except on days 21 and 28 in the Zataria group p = 0.07 and 0.08). Miconazole treatment reduced the number of denture colonies more efficiently than Z. multiflora except for day 21 when the efficacy of both groups was similar (p = 0.17). The results indicate that Z. multiflora gel reduced the surface erythema of the palate more efficiently than miconazole gel but did not reduce the colony count of the denture surface as efficiently as miconazole. Copyright © 2006 John Wiley & Sons, Ltd.
Active packaging of UHT milk to prevent the development of stale flavour during storage
Authors: Perkins Melinda L. , Zerdin Katherine , Rooney Michael L. , D'Arcy Bruce R. , Deeth Hilton C.
Published: August 2006

Indirectly processed UHT milk was packaged in IntaseptTM aseptic pouches with (treatment) or without (control) oxygen‐scavenging film and stored for 14 weeks at 26 ± 0.3°C. Samples were analysed at 0, 4, 8 and 14 weeks for dissolved oxygen, stale flavour volatiles (methyl ketones and aldehydes) and free fatty acids. Discriminative subjective analysis of odour by a consumer panel was also conducted. The oxygen‐scavenging film was shown to significantly (p < 0.05) reduce dissolved oxygen content by 23–28% during storage. Significant reductions of 23–41% were also observed for some stale flavour volatiles, including three methyl ketones and two aldehydes. Free fatty acid levels remained far below threshold values, indicating that lipolytic rancidity would not interfere with the subjective analysis. However, the consumer panel failed to detect a significant difference in odour between the treatment and control samples. Copyright © 2006 John Wiley & Sons, Ltd.
A Single‐Molecule Förster Resonance Energy Transfer Analysis of Fluorescent DNA–Protein Conjugates for Nanobiotechnology
Authors: Kukolka Florian , Müller Barbara K. , Paternoster Stefan , Arndt Andreas , Niemeyer Christof M. , Bräuchle Christoph , Lamb Don C.
Published: August 2006

The development of nanobiotechnological devices requires the ability to build various components with nanometer accuracy. DNA is a well‐established nanoscale building block that self assembles due to specific interactions that are encoded in its sequence. Recently, it has become possible to couple proteins to DNA, thereby expanding the capabilities of DNA for use with molecular photonics and bioelectronics. Here, we present the design and characterization of a supramolecular Förster resonance energy transfer (FRET) system by using a fluorescent protein bound to single‐stranded DNA (ssDNA), a fluorophore attached to a second ssDNA molecule, and a complementary strand for hybridizing the two fluorophores together. The FRET efficiency was studied by using both ensemble and single‐pair FRET measurements. The distance between the two fluorophores was determined from the single‐pair FRET efficiency and could be described by a simple cylindrical model for the DNA. Hence, DNA can be used as a scaffold for positioning fluorescent proteins, as well as traditional fluorophores, with nanometer accuracy and shows great potential for use in the future of nanobiotechnology.
Cover Picture: Parallel Manipulation of Bifunctional DNA Molecules on Structured Surfaces Using Kinesin‐Driven Microtubules (Small 8‐9/2006)
Authors: Dinu Cerasela Zoica , Opitz Jörg , Pompe Wolfgang , Howard Jonathon , Mertig Michael , Diez Stefan
Published: August 2006

The cover picture describes the use of cellular machinery, in a cell‐free environment, for the generation of complex DNA structures. Individual DNA molecules (green) were bound to microtubules (red), which were allowed to glide over a kinesin‐coated surface. As the other ends of the DNA were specifically attached to micropatterned gold substrates, the motor forces induced DNA stretching (see inset) and network formation. The results serve as a proof‐of‐principle that biological machineries can be used in vitro to accomplish the parallel formation of highly structured DNA templates, which may have application in biophysics and nanoelectronics. For more information please read “Parallel Manipulation of Bifunctional DNA Molecules on Structured Surfaces using Kinesin‐Driven Microtubules” by M. Mertig, S. Diez, and co‐workers on page 1090 ff. (Franziska Friedrich is kindly acknowledged for her assistance with the cover picture).
Women's interpretation of an abnormal result on measurement of fetal nuchal translucency and maternal serum screening for prenatal testing of Down syndrome
Authors: Khoshnood B. , De Vigan C. , Blondel B. , Lhomme A. , Vodovar V. , Garel M. , Goffinet F.
Published: August 2006

Objective

To assess the effects of sociodemographic and health‐provider factors on women's understanding of abnormal results on measurement of nuchal translucency (NT) and maternal serum screening (MSS), 18 months after the implementation of a policy aimed at increasing women's awareness regarding MSS.

Methods

A representative sample of women (n = 734) who gave birth in Parisian maternity units in 1999 were asked about their understanding of an abnormal result on MSS and NT. We assessed the effects of sociodemographic and health‐provider factors on the probability of women interpreting an abnormal result correctly, misinterpreting it as a definitive diagnosis, or declaring that they did not know how to interpret the result. Response rate was 92% and the analyses included multinomial models.

Results

For both MSS and NT measurement, the majority of women interpreted an abnormal result correctly. However, there were substantial sociodemographic differences in the probability of women interpreting an abnormal result correctly, and more so in the probability of their declaring not to know how to interpret the result. The probability of correct interpretations was substantially higher, and that of declaring not to know how to interpret the result substantially lower, for MSS than NT measurement. However, for several sociodemographic groups, the proportion of women who misinterpreted an abnormal result on screening as indicative of a definitive diagnosis was also higher for MSS as compared with NT measurement.

Conclusions

These findings underscore the need for additional efforts, along with alternative strategies, to inform women about the implications of prenatal screening, particularly in the case of measurement of NT. Copyright © 2006 ISUOG. Published by John Wiley & Sons, Ltd.
Tumor angiogenesis assessed by three‐dimensional power Doppler ultrasound in early, advanced and metastatic ovarian cancer: a preliminary study
Authors: Alcázar J. L.
Published: August 2006

Objective

To evaluate tumor vascularity by three‐dimensional power Doppler ultrasound (3D‐PDU) in early and advanced stage primary ovarian cancers and in metastatic tumors to the ovary.

Patients and methods

This was a retrospective analysis of clinical and sonographic data from 49 women with primary ovarian cancers or metastatic tumors to the ovary. All women underwent 3D‐PDU prior to surgery. Vascularization index (VI), flow index (FI) and vascularization flow index (VFI) from solid portions or papillary projections in the tumors were calculated using the Virtual Organ Computer‐aided AnaLysis (VOCAL™) program. Definitive histological diagnosis was obtained in each case.

Results

Among the 49 women, 10 had stage I primary cancers (five low‐malignant potential tumors and five invasive tumors), 26 had advanced stage primary ovarian cancers and 13 had metastatic tumors to the ovary. Mean VI and VFI were significantly higher in advanced stage tumors and metastatic tumors as compared with early stage tumors. No differences in 3D‐PDU indices were found between advanced stage and metastatic cancers.

Conclusions

Vascular indices derived from 3D‐PDU tend to be higher in advanced stage and metastatic ovarian cancers as compared with early stage ovarian tumors. Copyright © 2006 ISUOG. Published by John Wiley & Sons, Ltd.
Korrosionsinhibierende Plasmapolymerschichten auf Stahluntergründen
Authors: Holzhausen Ute , Milliow Sieghard
Published: August 2006

Die plasmabasierte Oberflächentechnik ermöglicht wissenschaftlich‐technisch, wirtschaftlich und ökologisch interessante Alternativen zu herkömmlichen Vorbehandlungsverfahren.

Daher stand am iLF in den vergangenen Jahren die Entwicklung eines neuen Verfahrens zur Verbesserung der Korrosionsbeständigkeit von niedriglegierten Stahloberflächen durch ultradünne Plasmapolymerschichten im Vordergrund.

Im Anschluss an eine Plasmafeinstreinigung unter oxidativen Bedingungen sollten Plasmapolymerschichten mit einer korrosionsinhibierenden/passivierenden Wirkung abgeschieden werden.

Dazu werden während des Prozesses der Plasmapolymerisation siliziumorganischer Monomere Korrosionsinhibitormoleküle in die sonst elektrochemisch inaktive Schicht implantiert. Dadurch verbessert sich nachweislich der langfristige Korrosionsschutz. Ferner kann durch plasmatechnische Verfahren die Oberfläche der abgeschiedenen Plasmapolymerschicht so modifiziert werden, dass sie auch eine optimale Haftvermittlung aufweist.
Dramatic reduction in self‐injury in Lesch–Nyhan disease following S‐adenosylmethionine administration
Authors: Glick Norris
Published: August 2006

A man with Lesch–Nyhan disease (LND; OMIM 300322) experienced significantly reduced self‐injury and improved comfort while receiving S‐adenosylmethionine.
Structural and functional changes in peripheral vasculature of Fabry patients
Authors: Kalliokoski Riikka J. , Kalliokoski Kari K. , Penttinen Maila , Kantola Ilkka , Leino Aila , Viikari Jorma S. , Simell Olli , Nuutila Pirjo , Raitakari Olli T.
Published: August 2006

Objective: Fabry disease is a lysosomal storage disorder due to deficient α‐galactosidase A activity, which leads to glycosphingolipid accumulation especially in vascular smooth‐muscle and endothelial cells. Little is known about the effects of Fabry disease on peripheral artery function and structure. Therefore, we aimed to further characterize the peripheral vascular structural and functional changes in Fabry disease. Methods and results: We measured structural and functional vascular parameters, including intima‐media thickness (IMT) of brachial and carotid arteries and abdominal aorta, carotid and aortic compliance, and brachial artery flow‐mediated dilatation (FMD) in 17 Fabry patients and 34 healthy controls matched for age, sex and smoking. Carotid IMT (0.64 ± 0.15 vs 0.57 ± 0.12 mm), brachial IMT (1.02 ± 0.25 vs 0.74 ± 0.18 mm), and aortic IMT (0.31 ± 0.09 vs 0.26 ± 0.04 mm) were significantly increased, and brachial FMD was significantly impaired (6.3 ± 5.0 vs 9.7 ± 3.9%) in Fabry patients compared to healthy controls (p < 0.05 in all comparisons after adjustments for age, LDL‐cholesterol, and systolic blood pressure). No differences were observed in arterial compliance between the groups. Conclusions: These data suggest that Fabry disease affects arterial function and structure by disturbing peripheral endothelial function and promoting intima‐media thickening.