bluuebunny/crossref_metadata_2025 huggingface dataset:
Recognizing large donations to public goods: an experimental test
Authors: Clark Jeremy
Published: September 2002

Private charities often publicise generousindividualcontributions or contributors, possibly to encourage others to give. In contrast, public good experiments used to study voluntary giving commonly tell participants only oftotalcontributions. This paper reports an experimental test of the effect on contributions of supplying additional selective information. A control treatment is run that reveals only total contributions over ten one‐shot decision rounds. This is compared to a second treatment that also informs subjects of the maximum contribution made in their group after each round. In a third treatment, subjects are further given the opportunity to make costly rewards to the maximum contributor. Revealing generous contributions appears to raise average contributions slightly. Surprisingly, adding the ability to reward large contributors does little to generate further increases, though it significantly raises the variance of contributions. Copyright © 2002 John Wiley & Sons, Ltd.
Modelling of ciliary downstream collecting in suspension‐feeding invertebrates
Authors: Mayer Stefan
Published: September 2002

The motion of fluid and suspended particles in ciliary downstream collecting suspension feeding is investigated on the basis of both experimental and numerical work. Throughout the paper, the suspension‐feeding polychaete Sabella penicillus is chosen to be the model species. Particle retention rate measurements indicate that S. penicillus is able to retain effectively particles of sizes much smaller than the overall size of its filtering unit. From frame‐by‐frame analysis of microscopical video recordings of the feeding organ of S. penicillus particle trajectories and velocities are inferred. By numerically solving the quasi‐steady Stokes equations for creeping flow in a boundary integral equation formulation and by introducing simple steady and unsteady cilia models a simple computational model of the S. penicillus filtering unit is constructed. A percentage of computed fluid particle trajectories is found to follow pathlines which resemble the experimentally observed particle capture. The results indicate that particle capture in suspension‐feeding can be realized solely by particle kinematics of locally driven creeping flow field as they exist in ciliary driven flow. Copyright © 2001 John Wiley & Sons, Ltd.
Ligand–macromolecule complexes: affinity index determination by selective nuclear relaxation analysis
Authors: Rossi C. , Bonechi C. , Martini S. , Ricci M. , Corbini G. , Corti P. , Donati A.
Published: September 2002

Proton NMR selective and non‐selective spin–lattice relaxation rate measurements were used to monitor the strength of the overall complexation behaviour of a ligand (carbamazepine) toward a macromolecular receptor (albumin). The ‘affinity index,’ a quantitative parameter related to the strength of the ligand–macromolecule interaction, was determined from the experimental contribution of the bound ligand molar fraction to the observed selective spin–lattice relaxation rate. The effect of a second ligand (lamotrigine) on the carbamazepine–albumin interaction was also investigated and was found to have a modulation effect on the carbamazepine–albumin interaction. Copyright © 2001 John Wiley & Sons, Ltd.
Haptoglobin inhibits lecithin‐cholesterol acyltransferase in human ovarian follicular fluid
Authors: Balestrieri Marco , Cigliano Luisa , Simone Maria Laura De , Dale Brian , Abrescia Paolo
Published: September 2002

The activity of the enzyme lecithin‐cholesterol acyltransferase (LCAT; E.C. 2.3.1.43) is involved in the removal of cholesterol excess from peripheral cells. This activity is stimulated by the HDL (high density lipoprotein) apolipoprotein A1 (ApoA1). Haptoglobin (Hpt) was previously found to be associated with ApoA1 in ovarian follicular fluid. LCAT activity was analyzed in follicular fluids, collected from an IVF program, containing different amounts of Hpt or Hpt/ApoA1 ratio. Addition of purified Hpt to follicular fluid caused a decrease in the enzyme activity, which was measured as the rate of synthesis of cholesteryl esters. In the fractions of fluid proteins, as obtained by gel filtration chromatography, Hpt and HDL were titrated by ELISA while the LCAT activity was assayed by using radioactive cholesterol and purified HDL. When isolated LCAT was incubated with fractions containing different Hpt/ApoA1 ratios, the enzyme activity was found negatively correlated with the Hpt/ApoA1 ratio (P < 0.01). LCAT kinetic parameters were measured in two fractions with the same amount of ApoA1 (5 μg/ml) but different amounts of Hpt (0.69 or 3.77 μg/ml): the Vmax did not change while the Km values were 24.1 or 78.6 μM in the presence of the low or high Hpt level, respectively. The analysis of fluids associated with cytoplasmically mature MII oocytes, in a cross‐sectional study, confirmed that a negative correlation exists between the Hpt/ApoA1 ratio and the LCAT activity (P < 0.01). The results suggest that Hpt inhibits the reverse transport of cholesterol by preventing ApoA1 stimulation of the LCAT activity. Mol. Reprod. Dev. 59:186–191, 2001. © 2001 Wiley‐Liss, Inc.
Simultaneous sampling of event‐related BOLD responses in auditory cortex and brainstem
Authors: Backes W.H. , van Dijk P.
Published: September 2002

Event‐related functional magnetic resonance imaging (fMRI) was applied to investigate blood oxygen level dependent (BOLD) responses in the human auditory system. Auditory fMRI is hindered by the disturbing acoustical noise of echo planar imaging (EPI). A sparse acquisition technique was used in which the delayed hemodynamic response was imaged at discrete sampling time‐points after a brief auditory stimulus. Long repetition times (10 heartbeats (HBs)) were used to avoid interactions between the activation due to the sound stimulation and scanner noise. In addition, only a single slice was acquired, to ensure that the scanner noise was minimal in duration and intensity. The image acquisition was triggered by the HB to prevent artifacts from cardiac‐related brainstem motion. An image was acquired every 10th HB. Significant hemodynamic BOLD time‐course responses were measured from the primary and secondary auditory cortices, as well as the inferior colliculi in the brainstem. No systematic differences were found between the cerebral cortex and the brainstem in terms of activation amplitude or in onset time of the hemodynamic response. Apparently, the slow dynamic nature of the BOLD response signal is similar across spatially separated auditory brain regions, suggesting a corresponding design of vessels and capillaries. Magn Reson Med 47:90–96, 2002. © 2002 Wiley‐Liss, Inc.
Impact of navigator timing on free‐breathing submillimeter 3D coronary magnetic resonance angiography
Authors: Spuentrup Elmar , Manning Warren J. , Botnar René M. , Kissinger Kraig V. , Stuber Matthias
Published: September 2002

The purpose of this study was to investigate the impact of navigator timing on image quality in navigator‐gated and real‐time motion‐corrected, free‐breathing, three‐dimensional (3D) coronary MR angiography (MRA) with submillimeter spatial image resolution. Both phantom and in vivo investigations were performed. 3D coronary MRA with real‐time navigator technology was applied using variable navigator time delays (time delay between the navigator and imaging sequences) and varying spatial resolutions. Quantitative objective and subjective image quality parameters were assessed. For high‐resolution imaging, reduced image quality was found as a function of increasing navigator time delay. Lower spatial resolution coronary MRA showed only minor sensitivity to navigator timing. These findings were consistent among volunteers and phantom experiments. In conclusion, for submillimeter navigator‐gated and real‐time motion‐corrected 3D coronary MRA, shortening the time delay between the navigator and the imaging portion of the sequence becomes increasingly important for improved spatial resolution. Magn Reson Med 47:196–201, 2002. © 2002 Wiley‐Liss, Inc.
Effect of essential hypertension on kidney function as measured in rat by dynamic MRI
Authors: Laurent Didier , Poirier Kevin , Wasvary James , Rudin Markus
Published: September 2002

In this study, dynamic MRI was applied to investigate the effect of genetic hypertension on the renal clearance of Gd(DTPA). Assuming that the paramagnetic agent was essentially cleared through the kidney by glomerular filtration, a first‐order kinetic model was used to estimate a rate constant kcl describing the transport from the renal cortex to the inner medulla. Experiments were carried out on 12–15‐week‐old spontaneously hypertensive rats (young‐SHR) and age‐matched Wistar‐Kyoto rats (young‐WKY). An additional group of 22–25‐week‐old SHR (old‐SHR) was investigated to assess the long‐term effect of chronic hypertension on kidney function. The glomerular filtration rate as measured by the inulin method correlated well with kcl results as measured by MRI. A clearance index 30% lower than young‐WKY was observed in young‐SHR, reflective of a kidney dysfunction. In old‐SHR, kcl was only 50% of the young‐WKY value. As computed from Gd(DTPA) concentration profiles, this translated into delayed time‐to‐peak (TTP) values, decreased peak Gd(DTPA) concentrations ([Gd]peak), and a slow elimination of Gd(DTPA) from the blood pool, renal cortex, and inner medulla (e.g., high t1/2 values). Finally, using the same MRI approach, the data showed that the acute administration of the calcium antagonist verapamil at an antihypertensive dose was followed by a near normalization of SHR renal function. These results indicate that chronic hypertension remains a major pathogenic factor in the progression of glomerular degeneration, as opposed to a primary glomerular defect independent of systemic pressure. Magn Reson Med 47:127–134, 2002. © 2002 Wiley‐Liss, Inc.
Effect of age on muscle functions investigated with surface electromyography
Authors: Merletti Roberto , Farina Dario , Gazzoni Marco , Schieroni Maria Pia
Published: September 2002

The purpose of this study was to investigate changes in the surface electromyographic (EMG) signal as a means of defining age‐related central and peripheral mechanisms affecting muscle fatigue. Spectral and temporal variables of the surface EMG signal were studied during voluntary isometric contractions of the dominant biceps brachii muscle in a group of 8 healthy elderly men (age range 67–86 years) and a group of 10 healthy young men (age range 23–34 years). The maximal torque developed and the rate of decrease (slope) of spectral variables and conduction velocity (CV) were statistically higher in the young subjects than in the elderly subjects. Motor unit (MU) CV distribution was also estimated from the surface EMG signal and no statistical difference was observed in its variance between the two groups. These results confirm previous findings from the tibialis anterior muscle. Thus, changes in fiber type distribution and decrease in MU firing rate with aging may be factors determining the decrease in maximal voluntary contraction torque and in myoelectric manifestations of muscle fatigue. © 2002 John Wiley & Sons, Inc. Muscle Nerve 25: 65–76, 2002
Neuronal differentiation and long‐term survival of newly generated cells in the olfactory midbrain of the adult spiny lobster, Panulirus argus
Authors: Schmidt Manfred
Published: September 2002

The fate of continuously generated cells in the soma clusters of the olfactory midbrain of adult spiny lobsters, Panulirus argus, was investigated by in vivo pulse‐chase experiments with the proliferation marker 5‐bromo‐2′‐deoxyuridine (BrdU) combined with immunostainings for neuropeptides of mature neurons. A BrdU injection after a survival time (ST) of 14 h labeled about 100 nuclei in the lateral soma clusters (LC), comprised of projection neurons, and about 30 nuclei in the medial soma clusters (MC), comprised of local interneurons. The BrdU‐positive nuclei were confined to small regions at the inside of these clusters, which also contain nuclei in different phases of mitosis and thus represent proliferative zones. After STs of 2 weeks or 3 months, the number of BrdU‐positive nuclei was doubled, indicating a mitosis of all originally labeled cells. Dependent on ST, the BrdU‐positive nuclei were translocated from the proliferative zones towards the outside of the clusters, where somata of mature neurons reside. Immunostainings with antibodies to the neuropeptides FMRFamide and substance P, both of which label a large portion of somata in the MC and a pair of giant neurons projecting into the LC, revealed that in both clusters the proliferative zones are surrounded by, but are themselves devoid of, labeling. In the MC, some BrdU‐positive somata were double‐labeled by the FMRFamide antibody after an ST of 3 months, and by the substance P antibody after STs of 6 and 11/14 months, but not after 3 months. In the LC, BrdU‐positive somata after an ST of 3 months partially and after 6 and 11/14 months widely overlapped with the arborizations of the giant neurons, indicating the establishment of synaptic input. The experiments show that cells generated in proliferative zones in the LC and MC of adult spiny lobsters after a final mitosis differentiate into neurons within months, survive for at least 1 year, and are integrated into the circuitry of the olfactory midbrain. A new hypothesis about the mechanism of adult neurogenesis in the central olfactory pathway of decapod crustaceans is developed, linking it to neurogenesis during embryonic and larval development. © 2001 John Wiley & Sons, Inc. J Neurobiol 48: 181–203, 2001
Localization and imaging of local shunts in solar cells using polymer‐dispersed liquid crystals
Authors: Schmidt Jan , Dierking Ingo
Published: September 2002

An easy‐to‐use technique for the localization and imaging of local shunts in solar cells is introduced. The method is based on temperature‐sensitive polymer‐dispersed cholesteric liquid crystal foils, covering the reverse‐biased solar cell. The unique optical properties of the cholesteric liquid crystal, known as selective reflection, render the local shunts of a solar cell visible as a color distribution in the foil, which is directly correlated with the spatial shunt distribution. The novel method is applied to several laboratory and commercial silicon solar cells and its high sensitivity is demonstrated. Copyright © 2001 John Wiley & Sons, Ltd.
Cross‐resistance and inheritance of resistance to Bacillus thuringiensis toxin Cry1Ac in diamondback moth (Plutella xylostella L) from lowland Malaysia
Authors: Sayyed Ali H , Wright Denis J
Published: September 2002

A field population of Plutella xylostella from Malaysia (SERD4) was divided into five sub‐populations and four were selected (G2–G5) with the Bacillus thuringiensis insecticidal crystal (Cry) toxins Cry1Ac, Cry1Ab, Cry1Ca and Cry1Da. Bioassay at G6 gave resistance ratios of 88, 5, 2 and 3 for Cry1Ac, Cry1Ab, Cry1Ca and Cry1Da respectively compared with the unselected sub‐population (UNSEL‐SERD4). The Cry1Ac‐selected population showed little cross‐resistance to Cry1Ab, Cry1Ca and Cry1Da, (3‐, 2‐ and 3‐fold compared with UNSEL‐SERD4), whereas the Cry1Ab‐SEL sub‐population showed marked cross‐resistance to Cry1Ac (40‐fold), much greater than Cry1Ab itself. In contrast, the Cry1Ca‐ and Cry1Da‐SEL sub‐populations showed little if any cross‐resistance to Cry1Ac and Cry1Ab. The mode of inheritance of resistance to Cry1Ac was examined in Cry1Ac‐selected SERD4 by standard reciprocal crosses and back‐crosses using a laboratory insecticide‐susceptible population (ROTH). Logit regression analysis of F1 reciprocal crosses indicated that resistance to Cry1Ac was inherited as an incompletely dominant trait. At the highest dose of Cry1Ac tested, resistance was recessive, while at the lowest dose it was almost completely dominant. The F2 progeny from a back‐cross of F1 progeny with ROTH were tested with a concentration of Cry1Ac that would kill 100% of ROTH. The mortality ranged between 50 and 95% in seven families of back‐cross progeny, which indicated that more than one allele on separate loci were responsible for resistance to Cry1Ac.

© 2001 Society of Chemical Industry
Calculation of quasiparticle energy of molecular systems by the GW method
Authors: Ohta Y. , Maki J. , Yoshimoto T. , Shigeta Y. , Nagao H. , Nishikawa K.
Published: September 2002

The quasiparticle energy of the H2 molecule is calculated by using the GW method, in which the self‐energy operator fully depends on the frequency. The initial Green function G0 is constructed from the wave function obtained by the Hartree–Fock approximation (HFA) and local density approximation (LDA) in the framework of the density functional theory (DFT). From the results obtained we have shown that the wave function from the DFT–LDA is more effective than that from the HFA for G0. © 2001 John Wiley & Sons, Inc. Int J Quantum Chem 84: 348–353, 2001
Generalized spin orbital GW theory for spin‐frustrated and spin‐degenerate systems
Authors: Yamanaka S. , Shigeta Y. , Ohta Y. , Yamaki D. , Nagao H. , Yamaguchi K.
Published: September 2002

We proposed the ab initio linear combination of Gaussian type orbital (LCGTO) generalized spin orbital GW (GSO–GW) method and calculated triangular hydrogen molecules as models of the noncolinear magnetic clusters. A remarkable improvement of ionized potentials (IPs) by the GW procedure for GHFS solutions is observed in comparison with calculational results by full CI. © 2001 John Wiley & Sons, Inc. Int J Quantum Chem 84: 369–374, 2001
An atomic capacitance–polarizability model for the calculation of molecular dipole moments and polarizabilities
Authors: Jensen Lasse , Åstrand Per‐Olof , Mikkelsen Kurt V.
Published: September 2002

A classical interaction model for the calculation of molecular polarizabilities has been investigated. The model is described by atomic capacitancies, polarizabilities, and a parameter related to the size of the atom, where one set of parameters has been employed for each element. The model has been parameterized for the elements H, C, N, O, F, and Cl from quantum chemical calculations of the molecular polarizability and dipole moment for 161 molecules at the Hartree–Fock level. The atomic charge has been divided into a nuclear charge and an electronic contribution, which also allows for modeling the permanent molecular dipole moment. Results are presented for polyenes. Excellent agreement with quantum chemical calculations is obtained for the components of the polarizability perpendicular to the chain, but the results are less satisfying for the component along the chain. An inherent deficiency of using atomic capacitancies for large molecules and long chains is discussed. © 2001 John Wiley & Sons, Inc. Int J Quant Chem, 2001
A novel approach for identification and measurement of hemoglobin adducts with 1,2,3,4‐diepoxybutane by liquid chromatography/electrospray ionisation mass spectrometry and matrix‐assisted laser desorption/ionisation tandem mass spectrometry
Authors: Basile Adriana , Ferranti Pasquale , Pocsfalvi Gabriella , Mamone Gianfranco , Miraglia Nadia , Caira Simonetta , Ambrosi Luigi , Soleo Leonardo , Sannolo Nicola , Malorni Antonio
Published: September 2002

The structural characterisation of the adducts formed by in vitro interaction of hemoglobin (Hb) with 1,2,3,4‐diepoxybutane (DEB), the most reactive 1,3‐butadiene (BD) metabolite, was obtained by liquid chromatography/electrospray ionisation mass spectrometry (LC/ES‐MS) analysis of modified tryptic peptides of human hemoglobin chains. The reactive sites of human hemoglobin towards DEB and its hydroxylated derivatives (trihydroxybutyl (THB)‐derivatives) were identified through the characterisation of alkylated tryptic peptides by matrix‐assisted laser desorption/ionisation tandem mass spectrometry (MALDI‐MS/MS). Based on this characterisation, a procedure was set up to measure the Hb‐adducts of THB‐derivatives by isotope dilution mass spectrometry with the use of a deuterated peptide standard. The results obtained here could permit optimisation of molecular dosimetry of BD‐adducts, and extension of the analysis to the biological monitoring of occupational exposure to butadiene. Copyright © 2001 John Wiley & Sons, Ltd.
Reactions of first‐row transition metal ions with propargyl alcohol in the gas phase
Authors: Zhao Xiang , Xin Bin , Xing Xiaopeng , Zhang Xia , Wang Guanghui , Gao Zhen
Published: September 2002

The gas‐phase reactions with propargyl alcohol (PPA) of all the singly charged ions of the first‐row transition metals, generated by laser ablation in an external ion source, were studied by Fourier transform ion cyclotron resonance mass spectrometry (FT‐ICRMS.). The reactivities of the metal ions change irregularly across the periodic table, and the reactivity of each ion is a function of its electronic configuration and corresponding metal‐oxygen (M‐O) bond energies. The 10 metal ions were classified into three categories according to their reactivities: Sc+, Ti+ and V+ are the most reactive ions which react with PPA to give many kinds of oxygen‐rich products due to stronger M‐O bonds; Fe+, Co+ and Ni+ are less reactive; Cr+, Mn+, Cu+ and Zn+ are the most unreactive ions, due to the half and completely occupied valence electronic configurations. The order of reactivity is Ti+ > V+ > Sc+ ≫ Co+ > Fe+ ≈ Ni+ > Zn+ > Cr+ ≈ Mn+ ≈ Cu+. Copyright © 2001 John Wiley & Sons, Ltd.
A multi‐level satellite channel allocation algorithm for real‐time VBR data
Authors: Celandroni Nedo , Ferro Erina , Potortí Francesco
Published: September 2002

Integrated services over a shared satellite channel need a MAC protocol that is able to deal with real‐time traffic without substantially affecting the efficiency of the shared medium. Due to its bursty nature, MPEG coded VBR video transmission is one of the most challenging real‐time applications. In this paper, we analyse the statistical performance of a simple allocation method for VBR traffic by using an accurate statistical model of an MPEG‐2 VBR coded movie, whose traffic exhibits a peak to mean ratio of about 4. The results were obtained both analytically and by simulation, and show that our method is suitable for transmitting non‐interactive video and best‐effort traffic on the same satellite link. The efficiency of the proposed method shows no dependency on the statistical properties of the input traffic. Copyright © 2002 John Wiley & Sons, Ltd.
Initial growth of Au on oxides
Authors: Guo Qinlin , Luo Kai , Davis Kent A. , Goodman D. W.
Published: September 2002

The growth of Au clusters on TiO2(110)−(1 × 1) and −(1 × 2) single‐crystal surfaces and on ordered Al2O3 films prepared on Re(0001) has been studied by low‐energy electron diffraction (LEED), Auger electron spectroscopy (AES), low‐energy ion scattering spectroscopy (LEISS) and high‐resolution electron energy‐loss spectroscopy (HREELS). The results indicate that Au forms two‐dimensional islands on the TiO2(110) surface at initial deposition of Au. On the alumina film, Au initially grows as three‐dimensional clusters. The coverage of Au at which Au clusters change from non‐metallic to metallic properties is found to be >0.3 monolayer equivalent (MLE) of Au deposition based on the energy shift of the surface plasmon measurements. Copyright © 2001 John Wiley & Sons, Ltd.
Studies on the surface migration of adsorbed oxygen from noble metals to silver over binary catalysts
Authors: Huang W. X. , Teng J. W. , Bao X. H.
Published: September 2002

Adsorbed oxygen migration from noble metals to silver was investigated on both an Ag/Pt(110) model catalyst and Al2O3‐supported Ag–Pd catalysts by photoelectron emission microscopy (PEEM) and oxygen temperature‐programmed desorption (TPD). On the CO‐precovered Ag/Pt(110) surface, oxygen was observed to diffuse from the Pt(110) surface to the Ag surface by PEEM. The diffusion of oxygen was coupled locally with a surface reaction of COad + Oad, giving rise to rapid propagation of the oxygen front. Migration of oxygen from the Pd surface to the Ag surface was proved also by oxygen TPD experiments on Al2O3‐supported Ag–Pd catalysts. Copyright © 2001 John Wiley & Sons, Ltd.
Adlayer structure of 1‐C18H37 SH molecules: scanning tunnelling microscopy study
Authors: Xu Qing‐Min , Wan Li‐Jun , Wang Chen , Bai Chun‐Li
Published: September 2002

The adlayer structure of 1‐octadecanethiol (1‐C18H37SH) is investigated by scanning tunnelling microscopy (STM) with bare and chemically (I and S) modified Pt/Ir tips. The molecules were observed to form a well‐ordered self‐assembly monolayer on highly oriented pyrolytic graphite. The alkyl chains of molecules were clearly imaged by bare tips. The S‐modified tip was found to be effective to reveal the structural details of thiol groups (SH). Based on the STM results and theoretical calculations, a model for a 1‐octadecanethiol adlayer is proposed. Copyright © 2001 John Wiley & Sons, Ltd.
Molecular organization of diolefinic compounds observed with scanning tunnelling microscopy
Authors: Wu Peng , Zeng Qing‐dao , Wang Chen , Bai Chun‐Li
Published: September 2002

We observed diolefinic molecules assembled on a graphite surface with submolecular resolution in ambient conditions using scanning tunnelling microscopy (STM) and discussed the arrangement of the molecules. Furthermore, the photopolymerization process was studied using STM. Copyright © 2001 John Wiley & Sons, Ltd.
Brain, eye, and face defects as a result of ectopic localization of Sonic hedgehog protein in the developing rostral neural tube
Authors: Nasrallah Ilya , Golden Jeffrey A.
Published: September 2002

Background

Normal development of the face, eyes, and brain requires the coordinated expression of many genes. One gene that has been implicated in the development of each of these structures encodes the secreted protein, Sonic hedgehog (Shh). During central nervous system development, Shh is required for ventral specification along the entire neural axis. To further explore the role of Shh in chick brain and craniofacial development, we overexpressed Shh in the developing rostral neural tube

Methods

In order to determine if Shh is sufficient to ventralize the forebrain, we localized ectopically recombinant Shh protein to the rostral neural tube of chick embryos. The resulting embryos were evaluated morphologically and by assaying gene expression.

Results

Disruption in normal gene expression patterns was observed with a reduction or loss in expression of genes normally expressed in the dorsal forebrain (wnt‐3a, wnt‐4, and Pax‐6) and expansion of ventrally expressed genes dorsally (HNF‐3β, Ptc). In addition to the genetic alterations observed in the neural tube, a craniofacial phenotype characterized by a reduction in many cranial neural crest‐derived structures was observed. The eyes of Shh‐treated embryos were also malformed. They were small with expansion of the retinal pigmented epithelium, enlarged optic stalks, and a reduction of neural retina.

Discussion: The ectopic localization of recombinant Shh protein in the rostral neural tube resulted in severe craniofacial anomalies and alterations of gene expression predicted by other studies. The system employed appears to be a model for studying the embryogenesis of malformations that involve the brain, eyes, and face. Teratology 64:107–113, 2001. © 2001 Wiley‐Liss, Inc.
Activation of Mitogen-activated Protein Kinase (Mitogen-activated Protein Kinase/Extracellular Signal-regulated Kinase) Cascade by Aldosterone
Authors: Hendron Eunan , Stockand James D.
Published: September 2002

Aldosterone in some tissues increases expression of the mRNA encoding the small monomeric G protein Ki-RasA. Renal A6 epithelial cells were used to determine whether induction of Ki-ras leads to concomitant increases in the total as well as active levels of Ki-RasA and whether this then leads to subsequent activation of its effector mitogen-activated protein kinase (MAPK/extracellular signal-regulated kinase) cascade. The molecular basis and cellular consequences of this action were specifically investigated. We identified the intron 1-exon 1 region (rasI/E1) of the mouse Ki-ras gene as sufficient to reconstitute aldosterone responsiveness to a heterologous promotor. Aldosterone increased reporter gene activity containing rasI/E1 threefold. Aldosterone increased the absolute and GTP-bound levels of Ki-RasA by a similar extent, suggesting that activation resulted from mass action and not effects on GTP binding/hydrolysis rates. Aldosterone significantly increased Ki-RasA and MAPK activity as early as 15 min with activation peaking by 2 h and waning after 4 h. Inhibitors of transcription, translation, and a glucocorticoid receptor antagonist attenuated MAPK signaling. Similarly, rasI/E1-driven luciferase expression was sensitive to glucocorticoid receptor blockade. Overexpression of dominant-negative RasN17, addition of antisense Ki-rasA and inhibition of mitogen-activated protein kinase kinase also attenuated steroid-dependent increases in MAPK signaling. Thus, activation of MAPK by aldosterone is dependent, in part, on a genomic mechanism involving induction of Ki-ras transcription and subsequent activation of its downstream effectors. This genomic mechanism has a distinct time course from activation by traditional mitogens, such as serum, which affect the GTP-binding state and not absolute levels of Ras. The result of such a genomic mechanism is that peak activation of the MAPK cascade by adrenal corticosteroids is delayed but prolonged.
Sustainable house design
Authors: Tenório Rosãngela , Pedrini Aldomar
Published: September 2002

This paper describes the methodology and the environmental assessment results of the proposed sustainable house in Fernando de Noronha island (038 51′ south and 328 25′ west), at the Northeast Coast of Brazil. The project was developed at the same site of the EMBRATEL telecommunications station built in 1997 and aimed to serve as a sustainable demonstration project at the island with minimum impact on the surroundings. Characterized by a warm‐humid tropical climate, overheating is the major problem all year round. Conservation of resources, such as water, energy and materials are the main concerns for architectural design projects to be implemented at this island context. This project concentrated on a design that could minimize energy requirements, through improvement of thermal comfort and low energy features, so the daytime electrical needs could be accomplished by the photovoltaic component (grid connected system). The evaluation of performance and feasibility of solutions were tested on a range of different simulation tools, such as VisualDOE‐2.1 (LBL, USA), Esp‐r (ESRU, UK), Ecotect (UWA, Australia) and PV Design PRO 4.0. (Sandia Labs‐USA). This project was a finalist at the WREA/UNESCO, World Renewable Energy 2000 environmental design competition.
IDEA: Interactive Database for Energy‐efficient Architecture
Authors: Heidt Frank D. , Clemens Joachim , Benkert Stephan , Weber Willi , Gallinelli Peter , Zirngibl Johann , François Claude , de Herde André , de Myttenaere Kristel , Yannas Simos
Published: September 2002

The project IDEA – Interactive Database for Energy‐efficient Architecture – is a multinational collaborative project to build a European knowledge base on advanced energy conscious building design. At the core of this project are two earlier multimedia developments, the Swiss program DIAS and the German adaptation NESA which present the principles and applications of solar architecture in the respective national contexts. IDEA aims to improve know‐how of European professionals and exchange of information between them. The database includes information on exemplary buildings, their technical concepts and on other specific conditions. IDEA presents the existing state of the art in the field of energy‐efficient architecture by means of a multimedia database of built examples, an encyclopedia of design concepts and a set of interactive design support tools. The built examples have been selected from around Europe. IDEA assembles technical information on materials and energy‐related standards and regulations and provides climatic data from all relevant European regions.
A new language of architecture: in quest for a sustainable future
Authors: Krishan Arvind
Published: September 2002

Sustainability and architecture are synonymous terms. While sustainability, physically and economically, is to a large extent manifest in the habitat built form, it is the scientific temper that will lend a design methodology and process, in order to render architecture sustainable. To achieve this; a “Energy‐resource Flow – Ecological Footprint” model is suggested which can help optimize input‐output parameters and their relationship. Possible formulation of these parameters leading to a sustainability indicator is also suggested. This leads to a process of design and various actual projects in response to critical issues. Thus suggesting a new language of architecture.
Test length and validity revisited
Authors: Burisch Matthias
Published: September 2002

Results from three different subject samples extend earlier findings that lengthening a scale beyond some point can actually weaken its validity. A near‐optimal algorithm selected the most valid aggregate of items from a common pool. Findings were then cross validated in a second sample. From this procedure emerged fairly short scales with acceptable cross validities, but only if the item pool had been prescreened for content saturation. Under these circumstances, even extremely short scales of two to four items each, which had survived double cross validation, suffered hardly any loss of cross validity. In a third sample they outperformed standard scales eight times as long. © 1997 John Wiley & Sons, Ltd.
Monomeric and Polymeric Tetra-aminophthalocyanatocobalt(II) Modified
Electrodes: Electrocatalytic Reduction of Oxygen
Authors: TSE YU-HONG , JANDA PAVEL , LAM HERMAN , ZHANG JIUJUN , PIETRO WILLIAM J. , LEVER A. B. P.
Published: September 2002

The monomeric and polymeric tetra-aminophthalocyane to, cobalt(II)
species adsorbed onto graphite electrodes are active in electrocatalytic
oxygen reduction. While the monomeric species is unstable, the polymerized
species is an effective and stable reduction catalyst over a wide pH range.
Both the two-electron reduction of oxygen to hydrogen peroxide and the
four-electron reduction of oxygen to water are characterized by cyclic
voltammetry, rotating disc and rotating ring-disc studies with appropriate
theoretical analysis. Some mechanistic information is obtained. This is the
first cobalt phthalocyanine species to provide a four-electron reduction
pathway which exists over a wide pH range and is stable. The stability is
associated with the polymerization since the monomeric species is not
stable.
Photosensitization by the Near-IR-absorbing Photosensitizer Lutetium Texaphyrin: Spectroscopic, In Vitro and In Vivo Studies
Authors: KOSTENICH GENADY , BABUSHKINA TANYA , LAVI ADINA , LANGZAM YAKOV , MALIK ZVI , ORENSTEIN ARIE , EHRENBERG BENJAMIN
Published: September 2002

The spectroscopic and biological properties of the new photosensitizer lutetium texaphyrin (Lu-Tex) were assessed in vitro and in vivo on a C26 colon carcinoma model, in comparison with hematoporphyrin (Hp), photofrin II (PII) and chlorin e 6( Chl ). Strong binding of Lu-Tex to lipid bilayer membranes was observed. The results of confocal fluorescence microscopy on C26 cells showed that Lu-Tex was localized in small vesicles in the cytoplasm, possibly in the lysosomes, while Chl and Hp were distributed in larger cytoplasmic vesicles attributed to mitochondria. Scanning electron microscopy and X-ray microanalysis revealed that photodynamic therapy with Lu-Tex induced only slight damage to the cell membrane, leading to a delayed cell response. Chl and Hp caused significant structural damage to the outer cell membrane, resulting in ionic imbalance and fast cell death. The in vitro quantitative assessment of the relative efficiency per absorbed photon of the sensitizers revealed that Lu-Tex was less effective than Chl and Hp . However, the results of our in vivo study showed that at the same light and drug doses the anti-tumor efficiency of the agents was in the following order: Lu-Tex > Chl > PII . The strong in vivo anti-tumor effect of Lu-Tex can be explained by its higher integrated absorption in the long-wavelength range.
Kinetics and Mechanism of the Reaction of Mercury(II) with a Water-soluble Octabromoporphyrin
Authors: NAHAR N. , TABATA M.
Published: September 2002

The reaction of mercury(II) hydroxide with 2,3,7,8,12,13,17,18-octabromo-5,10,15,20-tetrakis(4-sulfonatophenyl)porphyrin, [Formula: see text]( H 2P4−), to form the mercury(II) porphyrin [( TPPSBr 8) Hg ]4−( HgP 4−) was investigated in the pH range 6.2-8.5. The observed rate constant was first-order with respect to the mercury(II) concentration and decreased with increasing pH from pH 6.2 to 7.5 and then increased from pH 7.5 to 8.5. The rate expression was written as d [ HgP 4−]/dt = (kHPK−1[ H +]−1 + k H 2 P + k H 3P K 1[ H +])(1 + K1[ H +] + K−1[ H +]−1)−1[ Hg ( OH )2][ H 2 P 4−]. The kHP, kH2P and kH3P values were found to be (1.33 ± 0.02) × 108, (5.50 ± 0.08) × 106 and (1.40 ± 0.08) × 108 M −1 s−1 respectively, with K1 = [ H 3 P 3−][ H 2 P 4−]−1[ H +]−1 = 104.83 ± 0.04 and K−1 = [ HP 5−][ H +][ H 2 P 4−]−1 = 1010.02 ± 0.02. The activation parameters were [Formula: see text] and ΔS‡ HP = 226 ± 22 J K −1 mol −1 for the k HP path, [Formula: see text] and [Formula: see text] for the k H 2 P path and [Formula: see text] and [Formula: see text] for the k H 3 P path. The kinetic results show the high reactivity of mercury(II) hydroxide towards the protonated porphyrin.
Electrochemistry of Metalloporphyrin Homo- and Hetero-dimers Containing Co, Ni or Cu Metal Ions
Authors: KADISH KARL M. , GUO NING , VAN CAEMELBECKE ERIC , PAOLESSE ROBERTO , MONTI DONATO , TAGLIATESTA PIETRO
Published: September 2002

The synthesis and electrochemical characterization of five covalently linked symmetrical and unsymmetrical metalloporphyrin dimers containing tetraphenylporphyrin (TPP), triphenylporphyrin (TriPP) or diethylhexamethylporphyrin (DEHMP) macrocycles are reported. The investigated compounds are represented as M(TPP-DEHMP)M ( M = Co , Ni , Cu ) and M(TPP-TriPP)M ( M = Ni , Cu ), where TPP-DEHMP and TPP-TriPP are the tetraanions of 1-[5-(10,15,20-triphenylporphyrinyl)]-4-[10-(2,18-diethyl-3,7,8,12,13,17-hexamethylporphyrinyl)]benzene and 1,4-bis-[5″-(10″,15″,20″-triphenylporphy-rinyl)]benzene respectively. The UV-vis spectra of the neutral dimers can be simply obtained by superimposing the spectra of the two corresponding monomeric (TPP)M and (DEHMP)M units, the latter of which is approximated by (OEP)M (TPP and OEP are the dianions of tetraphenylporphyrin and octaethylporphyrin respectively). The reduction potentials of the dimeric porphyrins are similar to those of the combined individual monomeric units. This is also the case for all oxidations of M(TPP-TriPP)M as well as the first TPP- and DEHMP-centered oxidations of M(TPP-DEHMP)M to give porphyrin π-cation radicals. However, the second DEHMP macrocycle-centered oxidations of M(TPP-DEHMP)M to give porphyrin dications occur at half-wave potentials which are 50-100 mV easier than E1/2 for the same ring-centered oxidations of the corresponding (OEP)M monomers. The electrochemical data indicate that there is an electronic interaction between the (TPP)M and (DEHMP)M units of M(TPP-DEHMP)M only under conditions where both macrocycles of the dimer have been converted to a porphyrin π-cation radical.
Porphyrin-centered Water-soluble Star-shaped Polymers: Poly(N-acetylethylenimine) and Poly(ethylenimine) Arms
Authors: JIN REN-HUA , MOTOYOSHI KOU-ICHI
Published: September 2002

Porphyrin-centered star-shaped polymers were synthesized through living cationic ring-opening polymerization of 2-methyl-2-oxazoline employing tetra(p-chloromethylphenyl)porphyrin (CMPP) and its zinc complex as initiators. The polymers were characterized by GPC, 1 H NMR and UV-vis and their properties were examined by fluorescence quenching.
Synthesis and Properties of Tetrakis(trimethylsilyl)-phthalocyaninatoruthenium(II)
Authors: DÜRR KAI , HANACK MICHAEL
Published: September 2002

Tetrakis(trimethysilyl)phthalocyaninatoruthenium(II) (5) has been synthesized via the biaxially coordinated (( CH 3)3 Si )4 PcRu (3- Clpy )2 (2) complex by thermal decomposition of the axial ligands of 2. (( CH 3)3 Si )4 PcRu (5) was characterized by NMR, IR and UV-vis spectroscopy and elemental analysis. The trisubstituted (( CH 3)3 Si )3 PcRu (3- Clpy )2 (3) and disubstituted (( CH 3)3 Si )2 PcRu (3- Clpy )2 (4) complexes, formed as side products during the thermolysis of 2, could be isolated and characterized.
Photophysical Behaviour of Corrole and its Symmetrical and Unsymmetrical Dyads
Authors: PAOLESSE ROBERTO , SAGONE FRANCESCO , MACAGNANO ANTONELLA , BOSCHI TRISTANO , PRODI LUCA , MONTALTI MARCO , ZACCHERONI NELSI , BOLLETTA FABRIZIO , SMITH KEVIN M.
Published: September 2002

The luminescence properties at room temperature and 77 K of octamethylcorrole are reported for the first time, together with the photophysical behaviour of corrole-corrole and porphyrin-corrole dyads covalently linked through the 10-position with a phenyl bridge. The photophysical properties of corrole free base are very similar to those of the porphyrin analogues, whereas the dimeric systems show luminescence bands different from those of the parent monomers, indicating an unexpectedly high degree of interaction between the chromophores. The porphyrin-corrole dyad undergoes photocatalysed ring opening of the corrole moiety to give the corresponding porphyrin-biliverdin species.
UV-vis and Binding Studies of Cobalt Tetrasulfophthalocyanine–Thiolate Complexes as Intermediates of the Merox Process
Authors: NAVID ALI , TYAPOCHKIN EDUARD M. , ARCHER CHARLES J. , KOZLIAK EVGUENII I.
Published: September 2002

Intermediates of the cobalt tetrasulfophthalocyanine ( CoTSPc )-catalyzed thiol autoxidation were studied by UV-vis spectroscopy. All thiolates react with CoTSPc resulting in the formation of 1:1 complexes. Three major factors control both the stability and aggregation of the complexes: thiolate basicity, metal-to-ligand charge transfer (MLCT) and π stacking. Basic thiolates partially reduce C oII TSPc , whereas CoTSPc complexes with low-basicity aliphatic thiolates ( p K a < 4) do not exhibit Co (II) reduction, based on the absence of the characteristic Co (I) charge transfer band at 450 nm. CoTSPc complexes with aliphatic and bulky aromatic thiolates appear to be aggregated in aqueous solutions and are characterized by a broad band at 650 nm. Non-bulky aromatic thiolates of low basicity ( p K a < 6) form unique stable monomeric Co II TSPc complexes. This unique spectral feature can be attributed to π stacking between the phthalocyanine ring and thiolate. Comparison of binding constants shows that the partial reduction of Co (II) significantly contributes to the thiolate binding. A combination of aromatic π stacking and MLCT appears to be responsible for the observed 1000-fold stronger binding of non-basic aromatic thiolates as compared with aliphatic ligands of similar basicity. Kinetic studies confirm the importance of the thiolate binding type for catalysis.
Synthesis of silicon tetrapyrazinoporphyrazines
Authors: KLEINWÄCHTER JÖRG , SUBRAMANIAN L. R. , HANACK MICHAEL
Published: September 2002

Symmetric, peripherally substituted dihydroxysilicon tetrapyrazinoporphyrazines 5 and 6 were synthesized by reacting the diiminoisoindolines 1 and 2 with SiCl 4 in pyridine as solvent at considerably low temperature followed by hydrolysis of the intermediate dichlorosilicon tetrapyrazinoporphyrazines 3 and 4. In addition, the preparation of the bisaxially substituted trialkylsilyloxysilicon tetrapyrazinoporphyrazines 11 and 12, the corresponding trialkylsilyloxyhydroxy compound 14 and the μ-oxo dimer 15 is also reported.
Pesticide residues and vertical integration in Florida strawberries and tomatoes
Authors: Kilmer Richard L. , Andre Anouk M. , Stevens Thomas J.
Published: September 2002

Government regulations and consumer concern about pesticide residues in food may increase the costs of production and marketing for producers and processors associated with food safety risks. Vertical coordination is an economic response for mitigating the costs associated with uncertain pesticide residue levels. Data from a survey of Florida strawberry and tomato growers were used to test the hypothesis that vertical integration is associated with a lower mean and variance of pesticide residues. The results confirm a significant negative relationship between vertical integration and fungicide and insecticide residues in Florida strawberries and insecticides in Florida tomatoes. However, fungicides in tomatoes had the opposite effect. [Econ‐Lit citations: L220, L660] © 2001 John Wiley & Sons, Inc.
Invasive aspergillosis in haematological malignancies: Clinical findings and management for intensive chemotherapy completion
Authors: Nosari Annamaria , Oreste Pierluigi , Cairoli Roberto , Montillo Marco , Carrafiello Gianpaolo , Astolfi Alberto , Muti Giuliana , Marbello Laura , Tedeschi Alessandra , Magliano Enrico , Morra Enrica
Published: September 2002

Sixty‐one cases of Aspergillus infection (35 acute myeloid leukemia, 15 acute lymphoid leukemia, one myelodysplastic syndrome, two aplastic anemia, eight non‐Hodgkin's lymphoma) seen in our department between January 1989 and July 1999 were studied retrospectively to evaluate the clinical characteristics, to ascertain the factors that influenced the outcome from mycotic infections, and whether early diagnosis and prolonged therapy permitted completion of scheduled intensive chemotherapy and bone marrow transplantation (BMT) without fungal recurrence. The patients were divided into three diagnostic categories: proven aspergillosis (autoptic or histologic diagnosis) n = 39, probable aspergillosis (radiological diagnosis with positive microbiology) n = 9, and possible aspergillosis (radiological diagnosis alone) n = 13. In the same period among 675 acute leukemia patients the incidence of proven or probable aspergillosis was 7.1%. At onset of infection 92% of patients were neutropenic (< 0.5 × 109/L). The most frequent site of infection was the lung (90%); disseminated disease was present in 20 patients. Among 44 assessable patients, 12 (27%) failed to respond to early antifungal therapy and died. Thirty‐two patients were cured with antifungal treatment, three of five nonneutropenic with only itraconazole, the others with amphotericin B 1 mg/Kg/day with or without itraconazole subsequently or with liposomal amphotericin, Ambisome, if renal toxicity occurred. Twenty‐four of 29 neutropenic responders, all affected by acute leukemia, continued scheduled intensive chemotherapies. Pulmonary lobectomy was successfully combined with medical treatment in two cases before scheduled BMT. After infection nine patients were submitted to BMT (six allo, one marrow unrelated donor (MUD), two auto) with Ambisome or itraconazole as secondary prophylaxis without fungal relapse (follow‐up: 25–99 months). The median time from fungal infection to transplant was five months, range 3–10. Thirteen of 29 surviving patients had leukemia relapse, but only three (23%) of these showed also fungal infection recurrence. In conclusion, a high index of suspicion and careful clinical and radiological examinations are the key to identifying infected patients early and to programming the following therapeutic steps. Above all in leukemia patients, prompt and aggressive administration of antifungal agents seems to improve the outcome of invasive fungal disease and to permit intensive chemotherapy completion and transplant. Am. J. Hematol. 68:231–236, 2001. © 2001 Wiley‐Liss, Inc.