bluuebunny/crossref_metadata_2025_split huggingface dataset:
Enhancement of natural disease resistance in potatoes by chemicals
Authors: Andreu Adriana B , Guevara María G , Wolski Erika A , Daleo Gustavo R , Caldiz Daniel O 
Published: January 2006

AbstractThe mechanism involved in systemic acquired resistance (SAR) can be non‐specifically induced in susceptible plants. In response to pathogens, plants' natural defence mechanisms include the production of lignin and phytoalexins and the induction of plant enzymes. The aim of this research was to study the induction of SAR mediated by the chemical activator DL‐3‐aminobutyric acid (BABA) and the fungicide fosetyl‐aluminium in potato cultivars with different levels of resistance against Phytophthora infestans (Mont) de Bary. To study the chemical induction of the resistance, the foliage of several potato cultivars was sprayed with BABA, fosetyl‐aluminium or water (as a control treatment). After 3 days the foliage was inoculated with P. infestans. Seven days after inoculation, development of disease symptoms in the foliage was assessed. In postharvest tuber samples, evidence for enhancement of the defence response was evaluated by measuring the protein content of several hydrolytic enzymes as well as the phenol and phytoalexin content. The highest level of protection against late blight was observed when the chemicals were applied at early stages of crop development. An increase in resistance to late blight was also detected in tubers after harvest. There was also an increase in the protein level of β‐1,3‐glucanase and aspartic protease as well as in the phenol and phytoalexin content of potato tuber discs obtained from postharvest tubers of treated plants. Thus the protective effect seemed to persist throughout the whole crop cycle. This treatment may offer the possibility of controlling both foliage and tuber blight and could have a major impact in reducing over‐winter survival of P. infestans in tubers. Copyright © 2006 Society of Chemical Industry
Effect of Bacillus thuringiensis subsp. israelensis and neonicotinoid insecticides on the fungus gnat Bradysia sp nr. coprophila (Lintner) (Diptera: Sciaridae)
Authors: Cloyd Raymond A , Dickinson Amy 
Published: January 2006

AbstractThe soil bacterium Bacillus thuringiensis Berliner subsp. israelensis (Bti), the neonicotinoid insecticides dinotefuran, imidacloprid, thiamethoxam and clothianidin and the insect growth regulator pyriproxyfen were evaluated to determine their efficacy against the larval stages of the fungus gnat Bradysia sp nr. coprophila (Lintner) in the laboratory. Treatments were applied as a drench to the growing medium in polypropylene deli containers. The Bti treatments had no effect on either instar tested, whereas all the other compounds negatively affected both the second and third instars. This study demonstrates that the soil bacterium B. thuringiensis var. israelensis may not be active on these larval stages, whereas the neonicotinoid insecticides and the insect growth regulator pyriproxyfen are effective on these stages. The fact that Bti is not effective on the second and third instars of the fungus gnat means that greenhouse producers using this insecticide must make applications before fungus gnat populations build up and before overlapping generations develop. Copyright © 2006 Society of Chemical Industry
Prediction of intergranular strains using a modified self‐consistent elastoplastic approach
Authors: Gloaguen David , Berchi Tarek , Girard Emmanuel , Guillén Ronald 
Published: January 2006

AbstractA novel approach is adopted to describe the plasticity evolution and determine the active deformation systems with an elastoplastic self‐consistent approach. A modified formulation of the crystal behaviour is proposed. This model is tested by simulating the development of intergranular strains during uniaxial tension of MONEL‐400 as well as commercial purity aluminium. Neutron diffraction measurements of the elastic strains are used as a reference. The results show the relevance of the model for fcc polycrystals. (© 2006 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)
Anisotropic superparamagnetic states of an isolated ferromagnetic nanoparticle with uniaxial single‐ion anisotropy
Authors: Kokorina E. E. , Medvedev M. V. 
Published: January 2006

AbstractA molecular field approximation which takes into account both the thermal Brownian rotation of the total magnetic moment of a ferromagnetic nanoparticle and thermal deviations of atomic magnetic moments from the direction of the total magnetic moment has been elaborated. It has been shown by the example of an uniaxial single‐ion anisotropy of the second order that the different types of anisotropic superparamagnetic states can arise in such a nanoparticle depending on relationship between the anisotropy parameter (D > 0 or D < 0) and the intraparticle ferromagnetic exchange one (I > 0). In particular, for the case of a relatively weak anisotropy the ellipsoidal superparamagnetic state, as it is called, appears when the vector of the total magnetic moments moves during its Brownian rotation over the surface of prolated (at D > 0 – the easy‐axis anisotropy) or oblated (at D < 0 – the easy‐plane anisotropy) ellipsoid of rotation. (© 2006 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)
Co2MnSi as full Heusler alloy ferromagnetic electrode in magnetic tunneling junctions
Authors: Reiss G. , Hütten A. , Kämmerer S. , Schmalhorst J. 
Published: January 2006

AbstractThe discoveries of antiferromagnetic coupling in Fe/Cr multilayers by Grünberg, the Giant MagnetoResistance by Fert and Grünberg and a large tunneling magnetoresistance at room temperature by Moodera have triggered enormous research on magnetic thin films and magnetoelectronic devices. Large opportunities are especially opened by the spin dependent tunneling resistance, where a strong dependence of the tunneling current on an external magnetic field can be found. In order to obtain large magnetoresistance effects, materials with strongly spin polarized electron gas around the Fermi level have to be found. New materials with potentially 100% spin polarization will be discussed using the example of the full Heusler compound Co2MnSi. First, experimental aspects of the integration of this alloy in magnetic tunneling junctions will be addressed. With these junctions, we obtain up to 100% TMR at low temperature. The current status of this research will then be summarized with special regard to the complex diffusion mechanisms occurring in these devices and to the properties of the interfaces between the Heusler material and the insulator. (© 2006 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)
Environmentally sustainable cities. Critical review and operational conditions
Authors: Bithas Kostas P. , Christofakis M. 
Published: January 2006

AbstractThe political objective calling for environmentally sustainable development has provided the canvas for lively dialogue amongst scientists and analysts. Be that as it may, what have been found wanting are operational conditions for the achievement of environmental sustainability within specific anthropogenic systems, with cities being cited as a prime example of such systems. Indeed, from a historical perspective, cities have always been based on the concentration of humans and man‐made elements, resulting in respective confinement of natural assets. As cities possess particular properties for their environmental basis, the general conditions governing sustainability require suitable modifications when applied to cities. In this context, the present paper examines the conditions for environmentally sustainable development in urban systems. The specific natural and socioeconomic characteristics of urban systems are systematically taken into account for defining environmentally sustainable development in cities. The paper proposes an operational framework for evaluating urban systems for their environmental performance. Urban systems, presenting specific characteristics necessary for creating welfare with high density, ask for particular conditions for their environmentally sustainable development. These conditions differ substantially from those defining sustainability in broader geographical systems. Copyright © 2006 John Wiley & Sons, Ltd and ERP Environment.
A discrete‐state discrete‐time model using indirect observation
Authors: Isaman Deanna J. M. , Herman William H. , Brown Morton B. 
Published: January 2006

AbstractThis research was motivated by a desire to model the progression of a chronic disease through various disease stages when data are not available to directly estimate all the transition parameters in the model. This is a common occurrence when time and expense make it infeasible to follow a single cohort to estimate all the transition parameters.One difficulty of developing a model of chronic disease progression from such data is that the available studies often do not include the transitions of interest. For example, in our model of diabetic nephropathy, many clinical studies did not differentiate between patients without nephropathy and those who had microalbuminuria (a pre‐clinical stage of nephropathy). Another difficulty was a lack of data to directly estimate parameters of interest. We consider models which can accommodate such difficulties.In this paper we consider the problem of estimating parameters of a discrete‐time Markov process when longitudinal data describing the entire process are not available. First, we present a likelihood approach to estimate parameters of a discrete‐time Markov model. Next, we use simulation to investigate the finite‐sample behaviour of our approach. Finally, we present two examples: a model of diabetic nephropathy and a model of cardiovascular disease in diabetes. Copyright © 2006 John Wiley & Sons, Ltd.
Assessing genetic effects in survival data by correlating martingale residuals with an application to age at onset of Huntington disease
Authors: Wintrebert Claire M. A. , Zwinderman Aeilko H. , Maat‐Kievit Anneke , Roos Raymund A. , van Houwelingen Hans C. 
Published: January 2006

AbstractGenetic models for survival data are hard to formulate and hard to fit. For example, the popular gamma‐frailty model for sib‐pair data does not generalize easily to extended pedigrees and is not easy to fit.In this paper we show how martingale residuals from a (marginal) Cox model can be employed to estimate the presence of a genetic effect and to estimate genetic correlations depending on the genetic distance (kinship).The methodology is applied to age at onset of Huntington disease (HD) in carriers of the HD gene. The number of CAG repeats in the HD gene is a well‐known predictor for age at onset of the disease. However, there is an indication that other genes might be involved as well; leading to unexplained familial clustering.Using our methodology, we found a clearly significant genetic association between the martingale residuals with correlations of about 0.6 for relatives that share 50 per cent of their genes (sib‐pairs and parent–child) and about 0.3 for relatives that share 25 per cent of their genes (grandparent–grandchild, uncle/aunt–niece/nephew). Copyright © 2006 John Wiley & Sons, Ltd.
Intraclass correlation coefficients and bootstrap methods of hierarchical binary outcomes
Authors: Ren Shiquan , Yang Shuqin , Lai Shenghan 
Published: January 2006

AbstractIntraclass correlation coefficients are designed to assess consistency or conformity between two or more quantitative measurements. When multistage cluster sampling is implemented, no methods are readily available to estimate intraclass correlations of binomial‐distributed outcomes within a cluster. Because statistical distribution of the intraclass correlation coefficients could be complicated or unspecified, we propose using a bootstrap method to estimate the standard error and confidence interval within the framework of a multilevel generalized linear model. We compared the results derived from a parametric bootstrap method with those from a non‐parametric bootstrap method and found that the non‐parametric method is more robust. For non‐parametric bootstrap sampling, we showed that the effectiveness of sampling on the highest level is greater than that on lower levels; to illustrate the effectiveness, we analyse survey data in China and do simulation studies. Copyright © 2006 John Wiley & Sons, Ltd.
Bayesian semi‐parametric ROC analysis
Authors: Erkanli Alaattin , Sung Minje , Jane Costello E. , Angold Adrian 
Published: January 2006

AbstractThis paper describes a semi‐parametric Bayesian approach for estimating receiver operating characteristic (ROC) curves based on mixtures of Dirichlet process priors (MDP). We address difficulties in modelling the underlying distribution of screening scores due to non‐normality that may lead to incorrect choices of diagnostic cut‐offs and unreliable estimates of prevalence of the disease. MDP is a robust tool for modelling non‐standard diagnostic distributions associated with imperfect classification of an underlying diseased population, for example, when a diagnostic test is not a gold standard. For posterior computations, we propose an efficient Gibbs sampling framework based on a finite‐dimensional approximation to MDP. We show, using both simulated and real data sets, that MDP modelling for ROC curve estimation closely parallels the frequentist kernel density estimation (KDE) approach. Copyright © 2006 John Wiley & Sons, Ltd.
Rapid Detection of Escherichia coli by Using Antibody‐Conjugated Silver Nanoshells
Authors: Kalele Suchita A. , Kundu Anita A. , Gosavi Suresh W. , Deobagkar Dileep N. , Deobagkar Deepti D. , Kulkarni Sulabha K. 
Published: January 2006

AbstractSilver shells of 20 nm thickness have been deposited on silica particles of 200 nm diameter with narrow size distribution. Silver nanoshells dispersed in water exhibit a strong surface plasmon resonance band at 443 nm. This band was found to be very sensitive to rabbit immunoglobulin G antibodies, which were anchored on the nanoshells. These in turn could be utilized to detect the presence of small (≈5) to large numbers (≈109) of Escherichia coli in water. The protocol presented here proves to be a specific, rapid, reliable, and inexpensive method to detect E. coli.
pH‐Sensitive Dispersion and Debundling of Single‐Walled Carbon Nanotubes: Lysozyme as a Tool
Authors: Nepal Dhriti , Geckeler Kurt E. 
Published: January 2006

AbstractHighly dispersed and debundled carbon nanotubes were prepared in an aqueous solution of lysozyme using a combination of ultrasonication and ultracentrifugation. The product is a pH‐sensitive dispersion, which remains in a highly dispersed state at pH<8 and pH>11, but in an aggregated state at pH 8–11. Photoluminescence measurements show that by changing the pH value, a reversible conversion of the highly dispersed state to the aggregated state (or vice versa) could be observed. Circular dichromism analysis confirmed that the secondary structure, as well as the majority of the tertiary structure, remains intact. Some lysozyme molecules were irreversibly bound to the nanotubes, which is possibly due to π–π or hydrophobic interactions. However, these interactions alone are not enough to produce fine dispersions of the nanotubes. Protonated amine interactions on the defect sites of the nanotubes play a vital role in the stabilization of the nanotubes below the isoelectric point and amine adsorption on the sidewalls of nanotubes occurs in cases where the pH value is higher than the isoelectric point.
Shape Control of II–VI Semiconductor Nanomaterials
Authors: Kumar Sandeep , Nann Thomas 
Published: January 2006

AbstractAnisotropic II–VI semiconductor nanocrystals and nanoparticles have become important building blocks for (potential) nanotechnological applications. Even though a wide variety of differently shaped nanoparticles of this class can be prepared, the underlying mechanisms are mostly not fully understood. This Review article provides a brief overview of the currently studied shape‐evolution mechanisms and the most prominent synthesis methods for such particles, with an aim to provide a fundamental understanding on how different morphologies evolve, and to function as a tool to aid in the preparation of specific nanocrystals.
Regulation of two distinct alcohol oxidase promoters in the methylotrophic yeast Pichia methanolica
Authors: Nakagawa Tomoyuki , Inagaki Atsushi , Ito Takashi , Fujimura Shuki , Miyaji Tatsuro , Yurimoto Hiroya , Kato Nobuo , Sakai Yasuyoshi , Tomizuka Noboru 
Published: January 2006

AbstractIn this study, two Pichia methanolica alcohol oxidase (AOD) promoters, PMOD1 and PMOD2, were evaluated in a promoter assay system utilizing the acid phosphatase (AP) gene from Saccharomyces cerevisiae (ScPHO5) as a reporter. Heterologous gene expression driven by the PMOD1 and PMOD2 promoters was found to be strong and tightly regulated by carbon source at the transcriptional level. PMOD1 was induced not only by methanol but also by glycerol. PMOD2 was induced only by methanol, although it was not repressed on the addition of glycerol to a methanol medium, suggesting that PMOD2 is regulated in a manner distinct from that of other AOD‐gene promoters. On the other hand, methanol and oxygen level‐influenced gene expression mediated by PMOD1 and PMOD2. PMOD1 expression was optimal at low methanol concentrations, whereas PMOD2 was predominantly expressed at high methanol and high oxygen concentrations. Based on these results, both PMOD2 and PMOD1 should be useful tools for controlling heterologous gene expression in P. methanolica. In particular, it should be possible to differentially control the production phases of two heterologous proteins, using PMOD1 and PMOD2 in the same host cell and in the same flask. Copyright © 2006 John Wiley & Sons, Ltd.
Nuclear-Spin Exchange Interaction in Solid 3He
Authors: Meyer Horst 
Published: January 2006

Solid 3He has an unusually large nuclear spin-spin exchange interaction, which is due to the large zero-point motion of the atoms. This exchange can be described by a Hamiltonian of the form ℋ = −ħJ I1 · I2. The parameter J is strongly dependent on the density, decreasing from ħJ/kB = 2×10−3°K at V = 24.6 cm3/mole to ħJ/kB = 4×10−5 °K at V = 19.5 cm3/mole in the bcc phase. Hence the exchange is large in comparison with the energy of dipolar interaction Edip/kB = 2×10−8 °K. There is some evidence that the exchange is antiferromagnetic. One can calculate that at the highest stable molar volume, the transition to the ordered state should occur at about 1.8×10−3 °K. In the still more dense hcp phase, the exchange continues to decrease with molar volume.
The experimental evidence for this exchange comes from nuclear magnetic relaxation measurements taken in several laboratories. This paper presents a review of longitudinal and transverse relaxation data as well as diffusion data and their interpretation in terms of exchange. The consequences of exchange on some thermodynamic properties is then discussed.
Magnetic Moments and Hyperfine Interactions in Carbon-Stabilized Fe5Si3
Authors: Johnson C. E. , Forsyth J. B. , Lander G. H. , Brown P. J. 
Published: January 2006

Powder samples of the intermetallic compound Fe5Si3 which are stable at room temperature have been prepared by the addition of small quantities of carbon. They have been studied by x-ray, Mössbauer, and neutron-diffraction techniques. The structure remains essentially of the D88 type with 4FeI and 6FeII atoms in the hexagonal unit cell. The material is ferromagnetic with a Curie temperature of 112°±2°C. The Mössbauer spectra show a complex hyperfine pattern which is sensibly constant between 77° and 4.2°K and which can be analyzed as a superposition of a set of six sharp lines corresponding to a hyperfine field of 137 kOe on a more diffuse spectrum corresponding to a large hyperfine field. An estimate of the areas under two spectra is consistent with the smaller field being associated with FeI. The absorption by FeII nuclei shows that they are not all equivalent and have hyperfine fields ranging between 180 and 242 kOe. The FeI spectra show an axially symmetric quadrupole splitting of 12e2Qq = +0.35 mm/sec.
Neutron diffraction measurements at 4.2°, 100°, 290°K, and 150°C confirm that the spin direction is parallel to the haxagonal axis, and show that the magnetic moments are FeI = 1.05±0.15 μB, FeII = 1.55± 0.15 μB.
Thermal-Expansion Anomaly of MnCL2 · 4H2O near its Néel Point
Authors: Gonano R. , Philp J. W. , Adams E. D. 
Published: January 2006

We have observed a λ anomaly in the thermal expansion of MnCl2 · 4H2O due to antiferromagnetic ordering at 1.622°K. The linear thermal expansion coefficient, α, was measured along three mutually perpendicular directions between 0.4° and 4.2°K. The length of the sample determined the plate spacing of a capacitor, so that length changes of 0.05 Å could be measured using a capacitance bridge. Temperature resolution was about three microdegrees, with points taken at 40 μ°K intervals near the transition.
The expansion coefficient along the a axis. αa, is negative, while αb and αc′, are positive. The temperature dependences of αa, αb, αc′, and the specific heat are similar but not identical, in agreement with theoretical expectations. Near the transition, for 10−4&lt; | 1 − T/TN | &lt;10−1, the singularity in α appears to be logarithmic for T &lt; TN, and of the form | 1− T/TN |−p with p≃0.35 for T&gt; TN.
Phase II Clinical Trial With Pegylated Liposomal Doxorubicin (CAELYX®/Doxil®) and Quality of Life Evaluation (EORTC QLQ‐C30) in Adult Patients With Advanced Soft Tissue Sarcomas: A study of the Spanish Group for Research in Sarcomas (GEIS)
Authors: Poveda A. , López-Pousa A. , Martín J. , Del Muro J. García , Bernabé R. , Casado A. , Balañá C. , Sanmartín O. , Menéndez M. D. , Escudero P. , Cruz J. , Belyakova Elena , Menéndez D. , Buesa J. M. 
Published: January 2006

Background: Pegylated liposomal doxorubicin (PLD), a formulation with pharmacokinetic differences with respect
to doxorubicin (DXR), might benefit patients with advanced soft tissue sarcoma (STS) pretreated with DXR.Patients and methods: Patients with measurable and progressive STS received PLD at 35 mg/m2 every 3 weeks. Quality of life before and during treatment was assessed with EORTC QLQ‐C30.Results: Twenty‐eight patients, 22 DXR‐pretreated, were given 140 cycles (median 3, range 1–18). Activity in 27 patients
(5 GIST): one complete and one partial remission (both non‐GIST and without prior DXR), 12 stabilizations and
13 progressions (response rate 7.4%, 95% CI: 0–17%). Grade 3 toxicity: palmar‐plantar erythrodysesthesia (19% of
patients), stomatitis (4%) or cutaneous (4%). Neutropenia grade≥3 was detected in 16% of patients. Median relative
dose intensity was 95%. Progression‐free rate at 3 and 6 months was, respectively, 48 and 22%, median progression‐free
survival 5.8 months and median overall survival 8.7 months. QLQ‐C30 at baseline and at weeks 6–11 in 23 and 13 patients,
respectively, showed good reliability and validity. Quality of life did not seem to worsen during therapy.Conclusions: PLD did not induce objective remissions in 22 STS patients pretreated with DXR, but progression‐free
rate figures support the use of this agent in patients who have not progressed under a DXR‐containing regimen.
The toxicity observed was comparable to that of other PLD schedules.