bluuebunny/crossref_metadata_2025 huggingface dataset:
Pillars, Layers, Pores and Networks from Nickeltripyrrins: A Porphyrin Fragment as a Versatile Building Block for the Construction of Supramolecular Assemblies
Authors: Bröring Martin , Prikhodovski Serguei , Brandt Carsten D. , Cónsul Tejero Esther
Published: November 2006

Sterically hindered nickel‐ tripyrrins [Ni(trpy)X] with different di‐, tri‐ and tetradentate anions X have been prepared with the aim of finding coordination polymers formed by self‐association. The syntheses were performed by simple ligand‐exchange reactions and proceeded successfully with the pseudohalides CN−, OCN−, SCN−, SeCN−, N(CN)2− (dicyanoamido, dca) and C(CN)3− (tricyanomethanido, tcm), the cyanidometallates [Ag(CN)2]− and [Ni(CN)4]2− and the salicylate anion (sal−). X‐ray crystallographic analyses revealed that the complexes with cyanido and isocyanato ligands, as well as the compound with a salicylato ligand, are prototypes for structurally distinct monomeric species in the solid state, whereas one‐dimensional coordination polymers or supramolecular three‐dimensional networks are formed from all other combinations. The polymeric compounds display a variety of individual pillar and network architectures with functionalised pores and clefts and with the Ni(trpy) fragments in different relative orientations. Hydrogen bonding and π stacking were found to be additional structure‐directing effects, which increased the structural complexity of the system. The Ni(trpy) subunit has thus been proven to be a versatile building block for the construction of supramolecular assemblies and metal organic frameworks (MOFs) from pentacoordinate NiII ions.
Hydride Affinities of Substituted Alkenes: Their Prediction by Density Functional Calculations and Rationalisation by Triadic Formula
Authors: Vianello Robert , Peran Nena , Maksić Zvonimir B.
Published: November 2006

The hydride affinities (HAs) of ethene and its derivatives produced by substituents that vary greatly in their donor/acceptor properties are studied by the B3LYP/6‐311+G(2df,p)//B3LYP/6‐31G(d) method. The computed values are in very good agreement with the available experimental data. A useful by‐product of the calculations of thermodynamic data are the estimated adiabatic electron affinities. It turns out that derivatives involving monosubstituted CN and NO2groups, disubstituted CN, NO2and CF3groups and ethenes polysubstituted by these strongly electron‐accepting functionalities possess positive electron affinities, which implies that the corresponding ions are formed by energy release and are thus quite stable species. The most favourable sites of the hydride ion attack are identified and the trend of changes of hydride affinities is analysed and interpreted by a triadic formula, which discriminates between the initial, intermediate and final state properties. It is found that hydride affinities are rather well correlated with the adiabatic electron affinities, which means that the initial state (neutral molecule) and intermediate step (relaxation of the nuclei and electrons upon electron capture) effects are predominant factors. The quantitative information on the H–affinities can be obtained, however, only by including all terms appearing in the triadic formula. It is shown that Pearson’s HSAB concept does not work for hydride affinities. The idea of using hydride affinities as a measure of the electrophilic propensity of molecules is put forward. (© Wiley‐VCH Verlag GmbH & Co. KGaA, 69451 Weinheim, Germany, 2007)
Transmission pricing using the exact power and loss allocation method for bilateral contracts in a deregulated electricity supply industry
Authors: Adsoongnoen Cattareeya , Ongsakul Weerakorn , Maurer Christoph , Haubrich Hans‐Jürgen
Published: November 2006

This paper proposes a new method based on exact power and loss allocation for bilateral transactions under the enhanced single buyer model in the Thai electricity supply industry (Thai ESI). Generally, a transmission network is designed to transfer mainly active power. The transmission pricing for this active power charge in the Thai ESI comprises three components, namely the transmission use‐of‐system charge, the connection charge, and the common service charge. However, the calculation of transmission pricing, using marginal cost scheme, might not ensure revenue requirements of the transmission owner in case of a high reactive power demand in the network because a part of transmission line capacity is subsequently required for the reactive power transfer. Thus, the triangle method is used to segregate the transmission pricing by classifying active and reactive charges. The users are charged regarding their system usages by applying the exact power and loss allocation method. The proposed transmission pricing sends economic incentives to the users with fair charges. It ensures an investment recovery of the transmission owner in case of high reactive demand in the network. The Thai power 424‐bus network demonstrates the method exemplarily. Copyright © 2006 John Wiley & Sons, Ltd.
An evaluation of the self‐heating hazards of cerium(IV) nitrated treated towels using differential scanning calorimetry and thermogravimetric analysis
Authors: Hartman J. R. , Waters C. A. , Beyler C. L.
Published: November 2006

This study measured the Arrhenius kinetic parameters and heat of reaction using thermogravimetric analysis (TGA) and differential scanning calorimetric (DSC) for the combustion of untreated towels and towels treated with cerium(IV) nitrate. These parameters were used to calculate the self‐heating parameters, M and P (Self‐heating: Evaluating and Controlling the Hazard. Her Majesty's Stationery Office: London, 1984) and the critical pile sizes of the towels at several temperatures. The results from the TGA/DSC experiments support the conclusions by Beyler et al. (Fire and Materials 2005; 30:223–240) that the cerium(IV) nitrate treatment of towels significantly enhances the ignitability of the towels but that self‐heating is not a hazard for normal temperature storage scenarios other than bulk storage.

It was found that the kinetic reaction data measured by TGA and DSC are only useful for predicting the specific reaction hazard for materials stored above 100°C. A comparison of the self‐heating parameters measured by oven and kinetic reaction data methods for a number of materials suggests that the kinetic reaction data overestimate the critical pile size at temperatures below 100°C.

In addition, it was found that the kinetic reaction data measured by TGA can be used to determine the relative self‐heating hazards for modified materials. TGA testing with towels saturated with a 0.5 N solution of cerium(IV) nitrate (Ce(NO3)4) in a 2.0 N solution of nitric acid, a 2.0 N solution of sodium nitrate in 2.0 N nitric acid and simple 2.0 N nitric acid, showed that the sodium nitrate and nitric acid treated samples reacted at the same temperatures as the untreated towels, while cerium(IV) nitrate markedly reduced the reaction temperature. These tests clearly point to the importance of the cerium(IV) ion as an oxidizing agent. Thus, the TGA testing provided in a matter of days, insights that would have required months of oven testing. Copyright © 2006 John Wiley & Sons, Ltd.
Composition of the essential oils from the leaves of nine Pinus species and the cones of three of Pinus species
Authors: Kurose Kohsuke , Okamura Daigo , Yatagai Mitsuyoshi
Published: November 2006

The essential oils from leaves of Pinus koraiensis, P. merkusii, P. palustris, P. parviflora, P. petula, P. ponderosa, P. pumila, P. rigida and P. rudis and cones of P. densiflora, P. rigida and P. taeda were investigated by GC–MS. Yields of the oils were 0.08–2.33 (w/w). α‐Pinene (0.2–51.8%) and β‐pinene (0.1–38.2%) were contained in both the leaf and cone oils of Pinus species. The monoterpene fractions of Pinus leaf oils comprised mainly pinanes and menthanes. Pinanes were present in greater amounts than menthanes in the leaf oils of all the species except P. petula. The leaves of P. pumila contained caranes as major components, whereas those of P. parviflora contained camphanes as major components. As for sesquiterpenes in the leaf oils, caryophyllane and/or the cadinane group were the major components. The leaf oils of P. merkusii, P. petula and P. rudis contained larger amounts of caryophyllanes than those of the cadinane group. The sesquiterpenes of these three species were mainly caryophyllanes, while in the sesquiterpene fraction of other Pinus species the content of the cadinane group was larger than that of caryophyllanes. Concerning cone oils, P. rigida and P. taeda cones were mainly composed of monoterpenes, while P. densiflora contained sesquiterpenes as the main components. Copyright © 2006 John Wiley & Sons, Ltd.
An enhanced polygonal finite‐volume method for unstructured hybrid meshes
Authors: Ahn Hyung Taek , Carey Graham F.
Published: November 2006

Irregular hybrid meshes may excessively distort the node‐dual finite‐volume discretization. A new scheme is formulated that uses a different type of polygonal control volume. Superior stability of the polygonal scheme over the conventional node‐dual scheme is demonstrated on representative irregular hybrid meshes for incompressible viscous flow past a circular cylinder. Copyright © 2006 John Wiley & Sons, Ltd.
Baroclinic stability for a family of two‐level, semi‐implicit numerical methods for the 3D shallow water equations
Authors: Rueda Francisco J. , Sanmiguel‐Rojas Enrique , Hodges Ben R.
Published: November 2006

The baroclinic stability of a family of two time‐level, semi‐implicit schemes for the 3D hydrostatic, Boussinesq Navier–Stokes equations (i.e. the shallow water equations), which originate from the TRIM model of Casulli and Cheng (Int. J. Numer. Methods Fluids 1992; 15:629–648), is examined in a simple 2D horizontal–vertical domain. It is demonstrated that existing mass‐conservative low‐dissipation semi‐implicit methods, which are unconditionally stable in the inviscid limit for barotropic flows, are unstable in the same limit for baroclinic flows. Such methods can be made baroclinically stable when the integrated continuity equation is discretized with a barotropically dissipative backwards Euler scheme. A general family of two‐step predictor‐corrector schemes is proposed that have better theoretical characteristics than existing single‐step schemes. Copyright © 2006 John Wiley & Sons, Ltd.
The Cwm Llwyd Outlier, Carmarthenshire, South‐West Wales – Britain's deepest karstic subsidence or Variscan pull‐apart structure?
Authors: Walsh P. T. , Barclay W. J. , Battiau‐Queney Y.
Published: November 2006

The Cwm Llwyd Outlier of Namurian Middle Shales in the central part of the Black Mountain escarpment of South Wales is an unusual structure. It occupies a topographic depression located more than 2 km from the main outcrop of the Middle Shales and has a stratigraphic discordance with its wall‐rocks of more than 300 m. Previous interpretations advocating a karstic origin imply that this is the deepest known subsidence in Great Britain. However, although the outlier lies among some of the finest epikarst landforms in the country, several factors indicate that the subsidence was not caused by a karstic mechanism. These include the amount of stratigraphic displacement in contrast to the depth of available vertical space in the putative host Carboniferous Limestone, the relatively simple form of the outlier, and the absence of brecciation, marginal solution residues and associated palaeoendokarst features in the adjacent wall‐rocks.

The outlier is re‐interpreted here as the product of faulting which occurred during a Variscan strike‐slip or transpressive tectonic regime, producing local sinistral transtension that may have been re‐activated in the Palaeogene period. Remapping the outlier at a scale of 1:2 500 indicates that the present structure is related principally to a left‐stepping offset between the Cwm Llwyd and Llwyn Celyn faults. Analogies are drawn with the Cainozoic pull‐apart structures in Southwest England. Near‐surface reddening and kaolinization of the beds probably represent pre‐Pleistocene weathering. Copyright © 2006 John Wiley & Sons, Ltd.
Neonatal isolation impairs neurogenesis in thedentate gyrus of the guinea pig
Authors: Rizzi Simona , Bianchi Patrizia , Guidi Sandra , Ciani Elisabetta , Bartesaghi Renata
Published: December 2006

In the current study we examined the effects of early isolation rearing on cell proliferation, survival and differentiation in the dentate gyrus of the guinea pig. Animals were assigned to either a standard (control) or an isolated environment a few days after birth (P5–P6), taking advantage of the precocious independence from maternal care of the guinea pig. On P14–P17 animals received one daily bromodeoxyuridine injection, to label dividing cells, and were sacrificed either on P18, to evaluate cell proliferation or on P45, to evaluate cell survival and differentiation. In P18 isolated animals we found a reduced cell proliferation (−35%) compared to controls and a lower expression of brain‐derived neurotrophic factor (BDNF). Though in absolute terms P45 isolated animals had less surviving cells, they showed no differences in survival rate and phenotype percent distribution compared to controls. Looking at the location of the new neurons, we found that while in control animals 76% of them had migrated to the granule cell layer, in isolated animals only 55% of the new neurons had reached this layer. Examination of radial glia cells of P18 and P45 animals by vimentin immunohistochemistry showed that in isolated animals radial glia cells were reduced in density and had less and shorter processes. Granule cell count revealed that P45 isolated animals had less (−42%) granule cells than controls. Results show that isolation rearing reduces hippocampal cell proliferation, likely by reducing BDNF expression and hampers migration of the new neurons to the granule cell layer, likely by altering density/morphology of radial glia cells. The large reduction in granule cell number following isolation rearing emphasizes the role of environmental cues as relevant modulators of neurogenesis. © 2006 Wiley‐Liss, Inc.
Gastropods on Submersed Macrophytes in Yangtze Lakes: Community Characteristics and Empirical Modelling
Authors: Wang Hai‐Jun , Pan Bao‐Zhu , Liang Xiao‐Min , Wang Hong‐Zhu
Published: December 2006

Epiphytic gastropods in Yangtze lakes have suffered from large‐scale declines of submersed macrophytes during past decades. To better understand what controls gastropod community, monthly investigations were carried out in four Yangtze lakes during December, 2001–March, 2003. Composed of 23 species belonging to Pulmonata and Prosobranchia, the community is characterized by the constitution of small individuals. The average density and biomass were 417 ± 160 ind/m2 and 18.05 ± 7.43 g/m2, with maxima around August. Submersed macrophyte biomass is shown to be the key factor affecting species number, density, and biomass of gastropods. Accordingly, a series of annual and seasonal models yielding high predictive powers were generated. Preference analyses demonstrated that pulmonates and prosobranchs with different respiratory organs prefer different macrophyte functional groups. (© 2006 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)
Influence of UV‐B Irradiation on the Interspecific Growth Interaction between Heterosigma akashiwo and Prorocentrum donghaiense
Authors: Xie Zhihao , Xiao Hui , Cai Hengjiang , Wang Renjun , Tang Xuexi
Published: December 2006

Enhanced solar ultraviolet‐B (UV‐B) irradiation resulted from the stratospheric ozone depletion has adverse impacts on the primary productivity of marine algae. The effects of UV‐B enhancement on marine algae include reduction in photosynthesis and biomass, alteration in species competition, impaired chloroplast function, and damage to DNA. Harmful algal blooms (HAB) are an ubiquitous natural phenomenon caused by the excessive growth of phytoplankton. Many studies have examined the influence of supplemental UV‐B irradiation on different algae, but the effects of UV‐B irradiation on the interspecific growth interaction of HAB species has received little attention. In this study, Heterosigma akashiwo and Prorocentrum donghaiense were chosen to investigate the effect of UV‐B irradiation on the growth interaction between two HAB species by a co‐culture method. In a mixed culture experiment, H. akashiwo inhibited the growth of P. donghaiense in an inoculum dependent manner. In the absence of UV‐B irradiation, H. akashiwo dominated the competition with P. donghaiense under different inoculation proportions. Surprisingly, supplemental UV‐B irradiation alters the growth interaction between the two HAB species. P. donghaiense dominated the competition at the inoculation proportion of H: P = 1: 4. Supplemental UV‐B irradiation also weakens the competition dominance of H. akashiwo at the inoculation proportion of H: P = 1: 1 or H: P = 4: 1. (© 2006 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)
SVEP1 expression is regulated in estrogen‐dependent manner
Authors: Shur I. , Zemer‐Tov E. , Socher R. , Benayahu D.
Published: November 2006

The SVEP1 protein comprises modules related to the selectin super family and other motifs found in cell surface molecules. Earlier, we demonstrated that SVEP1 is expressed in osteogenic cells both in vivo and in vitro; in the current study we elaborate on the regulation of SVEP1 by 17β‐Estradiol (17βE2). SVEP1 message is expressed in vivo by bone marrow cells of sham‐operated rats, but not in estrogen‐depleted ovariectomized (OVX) rats. We demonstrated that 17βE2 treatment increases the level of the SVEP1 expression in cultured osteoblasts. SVEP1 was identified also in breast carcinoma (BC) cells known to reside in bone when metastasized from the primary tumor. SVEP1 expression was demonstrated by immunohistochemistry and fluorescence‐activated cell sorting (FACS) on various BC cell lines. The chromatin immunoprecipitation (ChIP) assay was applied to analyze the estrogen receptor (ER) binding to the putative SVEP1 promoter. We demonstrated that treatment with 17βE2 or ICI 182,780 affects this binding and regulates the mRNA and protein levels of SVEP1 in BC cells. We propose that SVEP1 may serve as a useful biomarker for studying the mechanism of cells interactions within the local microenvironment affected by estrogen. J. Cell. Physiol. 210: 732–739, 2007. © 2006 Wiley‐Liss, Inc.
Molecular imaging of angiogenesis
Authors: Neeman Michal , Gilad Assaf A. , Dafni Hagit , Cohen Batya
Published: November 2006

Angiogenesis (the growth of new blood vessels) is a complex multistep process that involves multiple cell types, numerous growth factors, and complex regulatory checks and balances. Tight control of vascular remodeling evolved to ensure stability of the vasculature while maintaining the body's ability to rapidly mount an angiogenic response requiring a high degree of plasticity. Angiogenesis is critical not only for physiological development, but also for the progression of pathologies, and is thus a target for therapeutic intervention. The importance of the process coupled with the ease of access for delivery of contrast agents makes the vasculature at large, and angiogenesis in particular, a favorable target of functional and molecular imaging. Recent developments in molecular imaging tools have expanded our views to encompass many components of the process. Functional imaging of blood volume, vessel permeability, and vasoreactivity is complemented by novel contrast agents that reveal specific targets on endothelial cells. Methods have been developed to label vascular cells so as to track their recruitment to sites of angiogenesis, and new “smart” contrast agents have been designed to reveal the activity of enzymatic reactions in altering the extracellular matrix (ECM) during angiogenesis. J. Magn. Reson. Imaging 2007. © 2006 Wiley‐Liss, Inc.
Quantitative analysis of whole‐tumor Gd enhancement histograms predicts malignant transformation in low‐grade gliomas
Authors: Tofts Paul S. , Benton Christopher E. , Weil Rimona S. , Tozer Daniel J. , Altmann Daniel R. , Jäger H. Rolf , Waldman Adam D. , Rees Jeremy H.
Published: November 2006

Purpose

To quantify subtle gadolinium (Gd) enhancement (signal increase) in whole‐tumor histograms and optimize their ability to predict subsequent malignant transformation in low‐grade gliomas (LGGs).

Materials and Methods

We analyzed histograms from 21 adult subjects with LGGs (eight nontransformers and 13 transformers) who had been imaged every six months for periods of two to five years. Before transformation these tumors were reported as radiologically non‐enhancing. Imaging included a T1‐weighted volume sequence before and after a double dose of Gd‐DTPA contrast agent. Image data sets were spatially registered and subtracted to obtain maps of percent enhancement (%E). Tumor outlines were defined on fluid‐attenuated inversion recovery (FLAIR) images, and the volumes were calculated. Histogram tails were analyzed to obtain the volume (mL) of subtly enhancing tissue (%E > 10%).

Results

Baseline enhancing volumes were higher for Ts than for NTs (P < 0.005). Kaplan‐Meier survival curves for a threshold of 4 mL showed clear differences at five years (P < 0.04). Pretransformation examinations predicted transformation (corrected threshold = 3.0 mL, P = 0.011).

Conclusion

Clear histogram differences at presentation suggest that the process of transformation starts very early. It is now possible to identify individuals at high risk for transformation at baseline by quantifying the volume of subtly enhancing tumor tissue, and such findings could have an impact on patient management. J. Magn. Reson. Imaging 2007. © 2006 Wiley‐Liss, Inc.
Cytokines, neurotrophins, and oxidative stress in brain disease from mucopolysaccharidosis IIIB
Authors: Villani Guglielmo R.D. , Gargiulo Nadia , Faraonio Raffaella , Castaldo Sigismondo , Gonzalez y Reyero Enrico , Di Natale Paola
Published: November 2006

Mucopolysaccharidosis IIIB (MPS IIIB; Sanfilippo syndrome type B) is characterized by profound neurological deterioration. Because a murine model of MPS IIIB disease is available, we focused on analysis of gene expression in the brain and cerebellum of 7‐month‐old MPS IIIB mice by pathway‐specific filter microarrays designed to probe apoptotic‐related, neurotrophic signalling molecules and inflammatory cytokines and receptors. Moreover, we extended the analysis with real‐time PCR performed at 1, 3, 7 months after birth. Bdnf was down‐regulated in the brain but up‐regulated in the cerebellum at 7 months of age, both at RNA and at protein levels. Cbln1 presented a threefold increase in the oldest brains while remaining unaltered in the cerebellum. Ccl3, Casp11, gp91phox, p67phox, and p47phox showed an increased expression in both brain and cerebellum at each examined time point. Ccl3, in particular, exhibited in both organs and at all times tested approximately a tenfold increase in its expression. Insofar as p47phox, p67phox, and gp91phox are all components of the phagocyte NADPH oxidase, our results suggest the possible involvement of the reactive oxygen species in the genesis of neurodegeneration in MPS IIIB disease. © 2006 Wiley‐Liss, Inc.
Synapse formation and elimination: Role of activity studied in different models of adult muscle reinnervation
Authors: Favero Morgana , Lorenzetto Erika , Bidoia Carlo , Buffelli Mario , Busetto Giuseppe , Cangiano Alberto
Published: November 2006

Synapse competition and elimination are a general developmental process both in central and in peripheral nervous systems that is strongly activity dependent. Some common features regulate synapse competition, and one of these is an application to development of the Hebb's postulate of learning: repeated coincident spike activity in competing presynaptic inputs on the same target cell inhibits competition, whereas noncoincident activity promotes weakening of some of the inputs and ultimately their elimination. Here we report experiments that indicate that the development of muscle innervation (initial polyneuronal innervation and subsequent synapse elimination) follows the Hebb's paradigm. We utilized two different models of muscle reinnervation in the adult rat: 1) we crushed nerves going to soleus or extensor digitorum longus muscles, to activate regeneration of the presynaptic component of the neuromuscular junctions (NMJ), or 2) we injected the soleus muscle with Marcaine (a myotoxic agent) to activate regeneration of the postsynaptic component, the muscle fiber. A condition of transient polyneuronal innervation occurs during NMJ regeneration in both cases, although the two models differ insofar as the relative strength of the competing inputs is concerned. During the period of competition (a few days or weeks, in Marcaine or crush experiments, respectively), we imposed a synchronous firing pattern on the competing inputs by stimulating motor axons distal to a chronic conduction block and demonstrated that this procedure strongly inhibits synapse elimination, with respect to control muscles in which regeneration occurs under natural impulse activity of motoneurons. © 2006 Wiley‐Liss, Inc.
Role of μ ‐opioid receptor in modulation of preproenkephalin mRNA expression and opioid and dopamine receptor binding in methamphetamine‐sensitized mice
Authors: Tien Lu‐Tai , Ho Ing‐Kang , Loh Horace H. , Ma Tangeng
Published: November 2006

We examined mRNA expression of preproenkephalin (PPE), a precursor of the endogenous opioid peptide enkephalin, and ligand binding to opioid and dopamine receptors in the striatum and nucleus accumbens in methamphetamine (METH)‐sensitized μ‐opioid receptor (μ‐OR) knockout mice and their wild‐type controls. Animals received daily intraperitoneal (i.p.) injections of METH (0, 0.625, 2.5, or 10 mg/kg) for 7 consecutive days to induce sensitization. Brain tissues were taken for biochemical analysis on experimental day 11 (4 days after the last injection). Expression of PPE mRNA and ligand binding were determined by in situ hybridization and autoradiography, respectively. Results indicate that there is an increase in PPE mRNA expression and a decrease in μ‐OR ligand binding in METH‐sensitized wild‐type mice. These changes were not detected in METH‐sensitized μ‐OR knockout mice. A significant increase in δ‐opioid receptor (δ‐OR) ligand binding was found in μ‐OR knockout mice. After repeated METH exposure, striatal and nucleus accumbal dopamine D1 receptor binding was decreased in μ‐OR knockout mice but was not changed in wild‐type mice. D2 receptor ligand binding was increased in wild‐type mice and exhibited a biphasic change, with a decrease at 0.625 and 2.5 mg/kg doses of METH and an increase with 10 mg/kg of METH, in μ‐OR knockout mice. These findings suggest that the μ‐OR is involved in the regulation of METH‐induced changes in an endogenous opioid peptide and dopamine receptors. © 2006 Wiley‐Liss, Inc.
Effects of Cymbopogon citratus L. essential oil on the growth, lipid content and morphogenesis of Aspergillus niger ML2‐strain
Authors: Helal G. A. , Sarhan M. M. , Abu Shahla A. N. K. , Abou El‐Khair E. K.
Published: November 2006

The mycelial growth of Aspergillus niger van Tieghem was completely inhibited using 1.5 (l/ml or 2.0 (l/ml of Cymbopogon citratus essential oil applied by fumigation or contact method in Czapek liquid medium, respectively. This oil was found also to be fungicidal at the same concentrations. The sublethal doses 1.0 and 1.5 (l/ml inhibited about 70% of fungal growth after five days of incubation and delayed conidiation as compared with the control. Microscopic observations using Light Microscope (LM), Scanning Electron Microscope (SEM) and Transmission Electron Microscope (TEM) were carried out to determine the ultra structural modifications of A. niger hyphae after treatment with C. citratus essential oil. The hyphal diameter and hyphal wall appeared markedly thinner. This oil also caused plasma membrane disruption and mitochondrial structure disorganization. Moreover, Ca+2, K+ and Mg+2 leakages increased from the fumigated mycelium and its total lipid content decreased, while the saturated fatty acids decreased and unsaturated fatty acids increased. These findings increase the possibility of exploiting C. citratus essential oil as an effective inhibitor of biodegrading and storage contaminating fungi and in fruit juice preservation. (© 2006 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)
Proteinase inhibitors from Streptomyces with antiviral activity
Authors: Serkedjieva Julia , Angelova Lidiya , Remichkova Mimi , Ivanova Iskra
Published: November 2006

An extensive screening study for the production of proteolytic inhibitors has been carried out on 75 Streptomyces strains. It was found that 18 of the strains and/or their variants (24%) produced proteinaceous substances, which belonged to the group of typical serine protease inhibitors. 23 samples were tested for inhibitory activity on the replication of influenza virus A/Germany/34, strain Rostock (H7N1) (A/Rostock) in chicken embryonic fibroblast (CEF) cells. Eleven of the tested samples (52.2%) significantly inhibited viral growth. Further the specific inhibitory effect on the replication of influenza virus A/Aichi/2/68 (H3N2) (A/Aichi) in Madin‐Darby canine kidney (MDCK) cells and on the growth of herpes simplex virus type 1, strain DA (HSV‐1) in Madin‐Darby bovine kidney (MDBK) cells was tested. Nine samples significantly inhibited A/Aichi and four – HSV‐1. The most effective inhibitors, produced by Streptomyces sp. 225b (SS 225b) and Streptomyces chromofuscus 34‐1 (SS 34‐1) protected mice from mortality in the experimental influenza A/Aichi virus infection. (© 2006 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)
Biodiversity of the genusFusariumin saline soil habitats
Authors: Mandeel Qaher A.
Published: November 2006

Fusariumspecies assemblage and diversity were investigated in eight different contrasting extreme saline soil habitats of the hot arid desert environment of Bahrain. Saline habitats are located towards the central‐southern part of Bahrain and featured by high electrical conductivity, slightly alkaline sandy soil, poor in nutrient sources and water holding capacity and mainly dominated by a salt‐tolerant flora. Quantification of data for the recovery ofFusariumspecies was based on morphological characters and counts by a series of ten fold dilutions plate method and direct soil plating, using two selective media supplemented with different NaCl concentrations. A total of 68 isolates, fluctuated between 1 and 23 per soil sample, were recovered among all habitats mostly at 0 and 5% NaCl concentrations, while no recovery was achieved at 20 and 25%. Grouping of these isolates has resulted in only five species (F. solani,F. oxysporum,F. chlamydosporum,F. equisetiandF. compactum), all of which were previously reported from the arid terrestrial habitats of Bahrain.F. solaniwas the most predominant species, based on relative density, frequency of occurrence and dominance values, followed byF. oxysporum, a finding consistent with other similar arid Sahara ecosystems. Evaluation of data, supported by analysis of diversity indices and community coefficients, revealed that desert mountain habitat followed by burial mounds habitat were highly homogeneous coupled with maximum species richness, diversity indices and evenness, whereas soil habitats like cliffs, coastal and Al‐Lowzy pit were the poorest. Moreover,in vitrotests showed that among other fusaria,F. solaniexhibited the highest tolerance to increase NaCl concentrations (25%) and temperature (28.3 mm linear growth at 35 °C). At 10% NaCl concentrations, significant reduction in linear growth extensions suppressed all species accompanied by massive thick‐walled, drought‐resistant chlamydospores formation, indicating that species are mainly thermo‐osmotolerant.Fusariumspecies recoveries were negatively significantly correlated (p< 0.05), with soil edaphic factors including salinity (r= –0.849) and soil moisture (r= –0.711). It is thus, proposed that inter and intra specific variation in theFusariumspecies community, in particular soil niche, is an outcome of the influence of bioclimatic, multi‐soil‐edaphic and biotic factors. (© 2006 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)
Acyl‐CoA oxidase activity from Beauveria bassiana, an entomopathogenic fungus
Authors: Alconada Teresa M. , Juárez M. Patricia
Published: November 2006

Beauveria bassiana produces acyl‐Co oxidase (ACO) in the P20000 g fraction of glucose and alkane‐grown cultures that catalyze the oxidation of acyl‐CoAs of different chain length. The activity was measured indirectly over the formation of H2O2 via the oxidative‐coupled assay system. ACO activity was assessed spectrophotometrically in the P20000 g fraction of glucose‐grown (FS0) and n ‐alkane grown cultures (FSalk), employing acyl‐CoAs of 16 to 24 carbons as substrates. A significant increment in the activity was observed in FSalk as compared to that of controls (FS0) in all conditions tested. Tetracosane‐grown cultures showed the highest activity with lignoceroyl‐CoA. The reaction conditions were optimized employing lignoceroyl‐CoA as substrate. A variable lag phase was observed when the activity was measured as a function of time. In the presence of 3‐amino‐1,2,4‐triazole (AT) to prevent H2O2 consumption by endogenous catalase, the lag phase became shorter and disappeared when AT concentrations were raised from 40 to 200 mM, thus enhancing acyl‐CoA oxidation. Enzyme activity reached its maximal value in the presence of 240 μg peroxidase, 0.08% Triton X‐100 and 36 μM bovine serum albumin. The apparent Km using lignoceroyl as substrate was estimated 2.5 μM. ACO showed high activity and stability between 30 and 40 °C, as well as between 7.0 and 9.0 pH, for 120 min, being 7.0 the optimum pH. (© 2006 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)
Use of the Porcine Intestinal Epithelium (PIE)‐Assay to analyze early stages of colonization by the human fungal pathogen Candida albicans
Authors: Wendland Jürgen , Hellwig Daniela , Walther Andrea , Sickinger Stefan , Shadkchan Yona , Martin Ronny , Bauer Janine , Osherov Nir , Tretiakov Alexander , Saluz Hans‐Peter
Published: November 2006

Virulence of C. albicans strains can be tested using a mouse model of haematogenously disseminated Candida cells. Initial steps of host‐pathogen contact such as adhesion and colonization are not taken into account due to the injection of Candida cells into the blood stream. Here we describe an assay, based on the ex vivo usage of porcine intestinal epithelium (PIE), that is useful to monitor the early stages of a C. albicans infection. The ability of C. albicans to undergo morphogenetic switching between yeast and hyphal stages is thought to contribute to its virulence. We found that hyphal formation was required to allow cells to colonize the PIE. The non‐filamentous mutant strains efg1/cph1 which lacks two of the central transcription factors that are required to promote hyphal growth and wal1 that carries a deletion of the C. albicans homolog of the human Wiskott‐Aldrich Syndrome Protein and is deficient in endocytosis showed only weak adherence. Furthermore, the wal1 mutant was found to be reduced in virulence using the mouse tail vein injection assay. We also analyzed the colonization properties of a variety of other mutant strains carrying deletions of either secreted aspartyl proteinase (SAP)‐family genes or amino acid permease encoding genes (GAP1, SSY1, and PUT4). Interestingly, the nag5 strain which lacks an N‐acetylglucosamine kinase showed enhanced filamentation and invasive growth as well as increased resistance against farnesol. (© 2006 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)
Adoption decision and use intensity of soil and water conservation measures by smallholder subsistence farmers in Dedo District, Western Ethiopia
Authors: Anley Y. , Bogale A. , Haile‐Gabriel A.
Published: December 2006

Soil degradation in the highlands of Ethiopia is a serious problem that threatens the sustainability of agriculture. Although efforts have been made to develop and promote several soil conservation technologies, their adoption has not been widespread. This study, based on responses from a sample of 101 households which operate on 204 plots in Western Ethiopia, interviewed in 2003 cropping year, employed a Tobit model to identify the main factors influencing farmers' decision to adopt and intensify the use of improved and indigenous soil and water conservation (SWC) measures. The results suggest that area of cultivated land, land/labour ratio, age and education level of household head and distance of the plot from home and slope of the plot provided statistically adequate predictive power on the use and intensity of SWC measures. These results are discussed and their implications for conservation programs are presented in the conclusion. Copyright © 2006 John Wiley & Sons, Ltd.
A new technique for proving realisability and consistency theorems using finite paraconsistent models of cut‐free logic
Authors: Daynes Arief
Published: November 2006

A new technique for proving realisability results is presented, and is illustrated in detail for the simple case of arithmetic minus induction. CL is a Gentzen formulation of classical logic. CPQ is CL minus the Cut Rule. The basic proof theory and model theory of CPQ and CL is developed. For the semantics presented CPQ is a paraconsistent logic, i.e. there are non‐trivial CPQ models in which some sentences are both true and false. Two systems of arithmetic minus induction are introduced, CL‐A and CPQ‐A based on CL and CPQ, respectively. The realisability theorem for CPQ‐A is proved: It is shown constructively that to each theorem A of CPQ‐A there is a formula A *, a so‐called “realised disjunctive form of A ”, such that variables bound by essentially existential quantifiers in A * can be written as recursive functions of free variables and variables bound by essentially universal quantifiers. Realisability is then applied to prove the consistency of CL‐A, making use of certain finite non‐trivial inconsistent models of CPQ‐A. (© 2006 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)
On ℵ0‐categorical weakly circularly minimal structures
Authors: Kulpeshov Beibut Sh.
Published: November 2006

We continue exploring analogues of o‐minimality and weak o‐minimality for circularly ordered sets. The main result is a description of ℵ0‐categorical 1‐transitive non‐primitive weakly circularly minimal structures of convexity rank 1 up to binarity (Theorems 4.4 and 4.5). (© 2006 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)
The weak pigeonhole principle for function classes in S12
Authors: Danner Norman , Pollett Chris
Published: November 2006

It is well known that S 12 cannot prove the injective weak pigeonhole principle for polynomial time functions unless RSA is insecure. In this note we investigate the provability of the surjective (dual) weak pigeonhole principle in S 12 for provably weaker function classes. (© 2006 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)
Calculus on strong partition cardinals
Authors: Henle James M.
Published: November 2006

In [1] it was shown that if κ is a strong partition cardinal, then every function from [κ ]κ to [κ ]κ is continuous almost everywhere. In this investigation, we explore whether such functions are differentiable or integrable in any sense. Some of them are. (© 2006 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)
A finite model property for RMImin
Authors: Hsieh Ai‐ni , Raftery James G.
Published: November 2006

It is proved that the variety of relevant disjunction lattices has the finite embeddability property. It follows that Avron's relevance logicRMIminhas a strong form of the finite model property, so it has a solvable deducibility problem. This strengthens Avron's result thatRMIminis decidable. (© 2006 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)
The strength of sharply bounded induction
Authors: Jeřábek Emil
Published: November 2006

We prove that the sharply bounded arithmetic T02in a language containing the function symbol ⌊x/2y⌋ (often denoted by MSP) is equivalent to PV1. (© 2006 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)
Can brand encounters inspire flashbulb memories?
Authors: Roehm, Jr. Harper A. , Roehm Michelle L.
Published: November 2006

Flashbulb memory has conventionally been studied in conjunction with negative public events, such as deaths of government officials. The present research investigates the possibility that this phenomenon may extend to events that are more positive and more private in nature, such as encounters with certain brands. Data from two studies suggest that flashbulb memories can arise from brand‐related experiences and that this may be especially likely when a brand is well‐differentiated from competitors and when an encounter is novel by virtue of its being a first‐ever interface between a consumer and a brand. © 2007 Wiley Periodicals, Inc.
The impact of attributions about life events on perceptions of foreign products: Contrasts in individualism and collectivism
Authors: Leigh James H. , Choi Youngtae
Published: November 2006

An event important to a consumer that occurred in a foreign country may serve to affect perceptions about the products from the country. Life events represent important experiences or circumstances that tend to exert a major influence on the individual. This article examines how consumer attributions made about a life event occurring in a foreign country vary across individuals from individualist and collectivist cultures, which serve to moderate the impact of the event on product perceptions. The research literature on life events, attribution theory, and cross‐cultural differences are used to formulate propositions regarding the relationship between life‐event attributions and subsequent perceptions of products from the foreign country. Implications and research directions are provided. © 2007 Wiley Periodicals, Inc.
On market mavens and consumer self‐confidence: A cross‐cultural study
Authors: Chelminski Piotr , Coulter Robin A.
Published: November 2006

Market mavens are attentive to media and important diffusers of marketplace information. This study examines the relationships between cultural individualism, general and consumer self‐confidence, and market mavenism in the context of two distinct cultural systems, the United States and South Korea. The examination of cross‐cultural equivalence of the constructs under study provides evidence for both configural and full or partial metric invariance. The results indicate that cultural individualism is positively related to general self‐confidence, general self‐confidence is positively related to consumer selfconfidence, and consumer self‐confidence is positively related to market mavenism. Additionally, this research shows that these relationships hold in both the U.S. and South Korean samples. The results of this study indicate that market mavenism, and thus levels of confidence about marketplace knowledge and speed of diffusion of such information may be more prevalent among the more individualistic than collectivistic consumers. © 2007 Wiley Periodicals, Inc.
Cover Picture: Macromol. Rapid Commun. 23/2006
Authors: Kunzelman Jill , Crenshaw Brent R. , Kinami Maki , Weder Christoph
Published: December 2006

Cover: Upon self‐assembly, certain oligo‐(phenylene vinylene) chromophores exhibit pronounced changes of their optical absorption properties. The integration of these dyes into a polymer matrix allows facile monitoring of mechanical stress or temperature history and is the basis for a versatile and general new approach for thermochromic and mechanochromic materials. Further details can be found in the article by J. Kunzelman, B. R. Crenshaw, M. Kinami, and C. Weder* on page 1981.
Consistent non‐cartesian off‐axis MRI quality: Calibrating and removing multiple sources of demodulation phase errors
Authors: Jung Youngkyoo , Jashnani Yogesh , Kijowski Richard , Block Walter F.
Published: November 2006

The consistency of off‐axis MRI with non‐Cartesian sequences across a large number of scanners is highly variable. Improper timing alignment of the gradient fields, data acquisition system, and real‐time frequency demodulation reference signal, which are necessary for off‐axis imaging, is an important source of this variability. In addition, eddy currents and anisotropic gradient delays cause deviations in k‐space trajectories that in turn make the demodulation reference signals inaccurate. A method is presented to quickly measure the timing error in the frequency demodulation reference signal and separate it from anisotropic gradient delays. k‐Space deviations, as measured with a previous gradient calibration technique, are shown to be a second source of demodulation phase errors that degrade image quality. Using the timing delay and k‐space deviations, a retrospective phase correction is applied to each k‐space sample before the data are regridded during reconstruction. The timing delays of four MR scanners were measured to be 4.2–7.5 μs below the manufacturer's suggested delay. Significant degradation in 3D radial (3D projection reconstruction (PR)) knee and breast images are retrospectively corrected while a partial prospective correction is applied for spiral imaging. The method allows for more consistent performance of non‐Cartesian sequences across multiple scanners without operator intervention. Magn Reson Med 57:206–212, 2007. © 2006 Wiley‐Liss, Inc.
Determination of regional brain temperature using proton magnetic resonance spectroscopy to assess brain–body temperature differences in healthy human subjects
Authors: Childs Charmaine , Hiltunen Yrjö , Vidyasagar Rishma , Kauppinen Risto A.
Published: November 2006

Proton magnetic resonance spectroscopy (1H MRS) was used to determine brain temperature in healthy volunteers. Partially water‐suppressed 1H MRS data sets were acquired at 3T from four different gray matter (GM)/white matter (WM) volumes. Brain temperatures were determined from the chemical‐shift difference between the CH3 of N‐acetyl aspartate (NAA) at 2.01 ppm and water. Brain temperatures in 1H MRS voxels of 2 × 2 × 2 cm3 showed no substantial heterogeneity. The volume‐averaged temperature from single‐voxel spectroscopy was compared with body temperatures obtained from the oral cavity, tympanum, and temporal artery regions. The mean brain parenchyma temperature was 0.5°C cooler than readings obtained from three extra‐brain sites (P < 0.01). 1H MRS imaging (MRSI) data were acquired from a slice encompassing the single‐voxel volumes to assess the ability of spectroscopic imaging to determine regional brain temperature within the imaging slice. Brain temperature away from the center of the brain determined by MRSI differed from that obtained by single‐voxel MRS in the same brain region, possibly due to a poor line width (LW) in MRSI. The data are discussed in the light of proposed brain–body temperature gradients and the use of 1H MRSI to monitor brain temperature in pathologies, such as brain trauma. Magn Reson Med 57:59–66, 2007. © 2006 Wiley‐Liss, Inc.