bluuebunny/crossref_metadata_2025 huggingface dataset:
Digitizing Francis and Clare of Assisi: Early Documents—Progress, Challenges, Implications
Authors: Benson Joshua
Published: November 2008

This article discusses the project to digitize the landmark series, Francis of Assisi: Early Documents and Clare of Assisi: Early Documents by the Institute for Digital Theology at Saint Louis University. The article describes some of the steps required for undertaking a digital project of this sort and reflects on the implications of the completed digital resource for the study of Franciscan Spirituality. The study concludes that this digital resource enhances study of these text greatly by allowing the user to compare and search texts in English or Latin, thereby providing a new level of critical study.
Louis Massignon, Catholicism and Islam: A Memoir Reflection
Authors: Mason Herbert W.
Published: November 2008

The article is a Memoir and Reflection, drawn from my direct acquaintance and friendship with the distinguished French Islamicist Louis Massignon between 1958 and 1962. It is a reflection on his unique place in Catholicism as a scholar and a witness of his faith and as a believer in the authenticity of Islam’s witness to God. To many of Massignon’s admirers and critics, his life and works stand for erudition of the first magnitude and his devotion typifies great humility and service to others. His drawing inspiration from the two faiths, and indeed the Jewish faith, however, suggests an enigma. After having published numerous essays and books and my translations of his major work on the Muslim martyr and mystic, al-Hallaj (858-922), the present article is an attempt to reflect still further on this enigma.
Toward a New French Edition of the Franciscan Sources: The Franciscan Message, Patrimony of Humanity
Authors: Dalarun Jacques
Published: November 2008

In 1968, Théophile Desbonnets and Damien Vorreux published the volume Saint François d’Assise. Documents, écrits et premières biographies : it was the first anthology of Franciscan early sources in a modern language. Forty years after, a new edition was needed. Published through Éditions franciscaines and Éditions du Cerf, under the direction of Jacques Dalarun, the new edition will offer a more abundant choice of texts, with entirely new French translations, new introductions partly written in collaboration with the Franciscan Institute of St. Bonaventure University (NY), with the support of the Scuola superiore di studi medievali e francescani of the Pontifical University Antonianum and the Collegio San Bonaventura. The hope of such a project is also to open a new season of international collaboration in Franciscan studies.
Is Spirituality the Future of Theology?: Insights from Bonaventure
Authors: Delio Ilia
Published: November 2008

The rise of Spirituality as an academic discipline in the twentieth century begs the question of relationship between spirituality and theology. This paper looks at the integration of spirituality and theology through the lens of the Franciscan theologian, Bonaventure of Bagnoregio. Bonaventure’s view of spirituality as the foundation of theology provides a healthy antidote to the pursuit of theology as an intellectual exercise. The import of doing theology as a way of life is discussed in light of our present age.
Forma Vivendi, Forma Orandi : Franciscan Forms of Living and Praying
Authors: Chinnici Joseph P.
Published: November 2008

This article is an article-review of a major collection of scholarly studies edited by Timothy J. Johnson, Franciscans at Prayer . In addition to describing the structure of the book, the author summarizes major insights from each of the sixteen articles and presents some evaluative comments. Indicating points of comparison with the Benedictine, Ignatian, and Carmelite traditions, he concludes by noting the need to explore a more synthetic understanding of the uniqueness of the Franciscan contribution. Based on the “logic of the Incarnation,” the Franciscan tradition of prayer might be characterized as the simultaneously joyful and sorrowful experience of God’s presence in Christ in creation, human history, and the Church.
Clear, Clearer, Clearer Still: The Figure of Clare in Recent Scholarship
Authors: Armstrong Regis J.
Published: November 2008

Reflecting on the resurgence of interest in texts by and about Clare of Assisi and the availability of new scholarly translations, the author reflects on how they have been interpreted. He turns to the articles of Sandra Scheiders, Bernard McGinn, et al., in the Christian Spirituality Bulletin and Spiritus which repeatedly wrestled with the definition of spirituality and questions of “the ancient reality” and “the ancient texts.” From their considerations of the “hermeneutical,” “historical-contextual,” and “theological” perspectives, the author suggests looking at the texts by and about Clare of Assisi through a prism and concludes by reflecting on the Trinitarian form of life given her by Francis of Assisi suggesting his utter respective for a feminine interpretation of the fundamental Christian mystery.
Reading for Transformation through the Poetry of Gerard Manley Hopkins
Authors: McAloon Francis X.
Published: November 2008

In this essay, Francis X. McAloon, S.J., grounds himself in the hermeneutical writings of philosopher Paul Ricoeur and Christian spirituality/New Testament scholar Sandra M. Schneiders, IHM, to propose an interdisciplinary approach to the investigation of Christian poetic prayer texts that is rooted in Christian spiritual experience, informed by literary and theological scholarship, and focused upon the potential power of certain poems to function as texts for transformative prayer. The article applies McAloon’s methodology to a critical and existential engagement with Hopkins’ sonnet of despair, “To seem the stranger.”
A Concept for the Fatigue Life Prediction of Components from an Aluminum-Steel Compound
Authors: Lamik A. , Leitner H. , Eichlseder W. , Riemelmoser F.
Published: November 2008

The goal of this research project is the development of a simulation model for lifetime estimation of components from AA6016-T4/FeP06 material compound. Since such components are manufactured predominantly by rolling (for manufacturing of the material compound) and deep-drawing, the influence of the plastic deformations during the manufacturing process on the fatigue behavior must be investigated. In particular, the influence of the rolling reduction on the behavior of FeP06 steel has a relevant effect on the fatigue life of this aluminum-steel compound. Simulation models for fatigue life estimation of this material compound must therefore consider the influence of the elastic plastic deformation which occurs during, e.g., rolling and deep-drawing processes. For this purpose, a new model for the generation of yield curve as a function of the rolling reduction of the material FeP06 was determined. The proposed yield curve model shows good results at low and high rolling reduction compared to the models of Voce and Swift. The lifetime estimation shows a substantial improvement of accuracy (600 %) by the consideration of the influence of the rolling reduction.
Study on Antioxidative Synergism of Molybdenum Dialkydithiocarbamate with Alkylated Diphenylamine Antioxidants
Authors: Zhang Yi , Zeng Xian-Jun , Hu Jian-Qiang , Fu Yan , Luo Yan
Published: November 2008

The antioxidation properties of molybdenum dialkyldithiocarbamate, p,p-dioctyldiphenylamine and mixed octylated and butylated diphenylamine additives in poly-α-olefin (PAO) lubricant or mineral oil 150 SN were evaluated by differential scanning calorimetry (DSC) and the Modified Penn State Micro-oxidation Test (PMOT). DSC test measures incipient oxidation temperature and oxidation induction time of the lubricants at high temperatures and the weight loss of oil with deposits formed are measured by the PMOT test. DSC results show that antioxidation properties and of p,p-dioctyldiphenylamine and octylated and butylated diphenylamine were improved significantly by molybdenum dialkyldithiocarbamate addition. PMOT results indicate that when it was combinied with p,p-dioctyldiphenylamine, molybdenum dialkyldithiocarbamate can also effectively reduce the increase in weight loss of oils and deposits formed in oils. These results suggest that the molybdenum dialkyldithiocarbamate shows a good antioxidative synergism with alkylated diphenylamine antioxidants. In addition, FTIR results from the PMOT test confirm that the addition of molybdenum dialkyldithiocarbamate can significantly enhance the oxidation induction time of oils containing p,p-dioctyldiphenylamine and inhibit formation of oxidation products including carbonyl bonds or hydroxyl group. ESR analysis from the PMOT test indicate that molybdenum dialkyldithiocarbamate may form stable radicals with arylamine by the coordination effect. Finally, the proposed mechanism of the inhibition involves a synergy between molybdenum dialkyldithiocarbamate and arylamine antioxidants.
Impact of Apolipoprotein E (ApoE) Polymorphism on Brain ApoE Levels
Authors: Riddell David R. , Zhou Hua , Atchison Kevin , Warwick Helen K. , Atkinson Peter J. , Jefferson Julius , Xu Lin , Aschmies Suzan , Kirksey Yolanda , Hu Yun , Wagner Erik , Parratt Adrienne , Xu Jane , Li Zhuting , Zaleska Margaret M. , Jacobsen J. Steve , Pangalos Menelas N. , Reinhart Peter H.
Published: November 2008

Inheritance of the apoE4 allele (ε4) increases the risk of developing Alzheimer's disease; however, the mechanisms underlying this association remain elusive. Recent data suggest that inheritance of ε4 may lead to reduced apoE protein levels in the CNS. We therefore examined apoE protein levels in the brains, CSF and plasma of ε2/2, ε3/3, and ε4/4 targeted replacement mice. These apoE mice showed a genotype-dependent decrease in apoE levels; ε2/2 >ε3/3 >ε4/4. Next, we sought to examine the relative contributions of apoE4 and apoE3 in the ε3/4 mouse brains. ApoE4 represented 30–40% of the total apoE. Moreover, the absolute amount of apoE3 per allele was similar between ε3/3 and ε3/4 mice, implying that the reduced levels of total apoE in ε3/4 mice can be explained by the reduction in apoE4 levels. In culture medium from ε3/4 human astrocytoma or ε3/3, ε4/4 and ε3/4 primary astrocytes, apoE4 levels were consistently lower than apoE3. Secreted cholesterol levels were also lower from ε4/4 astrocytes. Pulse-chase experiments showed an enhanced degradation and reduced half-life of newly synthesized apoE4 compared with apoE3. Together, these data suggest that astrocytes preferentially degrade apoE4, leading to reduced apoE4 secretion and ultimately to reduced brain apoE levels. Moreover, the genotype-dependent decrease in CNS apoE levels, mirror the relative risk of developing AD, and suggest that low levels of total apoE exhibited by ε4 carriers may directly contribute to the disease progression, perhaps by reducing the capacity of apoE to promote synaptic repair and/or Aβ clearance.
CLIC1 Function Is Required for β-Amyloid-Induced Generation of Reactive Oxygen Species by Microglia
Authors: Milton Rosemary H. , Abeti Rosella , Averaimo Stefania , DeBiasi Silvia , Vitellaro Laura , Jiang Lele , Curmi Paul M. G. , Breit Samuel N. , Duchen Michael R. , Mazzanti Michele
Published: November 2008

The Alzheimer's disease (AD) brain is characterized by plaques containing β-amyloid (Aβ) protein surrounded by astrocytes and reactive microglia. Activation of microglia by Aβ initiates production of reactive oxygen species (ROS) by the plasmalemmal NADPH oxidase; the resultant oxidative stress is thought to contribute to neurodegeneration in AD. We have previously shown that Aβ upregulates a chloride current mediated by the chloride intracellular channel 1 (CLIC1) protein in microglia. We now demonstrate that Aβ promotes the acute translocation of CLIC1 from the cytosol to the plasma membrane of microglia, where it mediates a chloride conductance. Both the Aβ induced Cl−conductance and ROS generation were prevented by pharmacological inhibition of CLIC1, by replacement of chloride with impermeant anions, by an anti-CLIC1 antibody and by suppression of CLIC1 expression using siRNA. Thus, the CLIC1-mediated Cl−conductance is required for Aβ-induced generation of neurotoxic ROS by microglia. Remarkably, CLIC1 activation is itself dependent on oxidation by ROS derived from the activated NADPH oxidase. We therefore propose that CLIC1 translocation from the cytosol to the plasma membrane, in response to redox modulation by NADPH oxidase-derived ROS, provides a feedforward mechanism that facilitates sustained microglial ROS generation by the NAPDH oxidase.
Learning and Survival of Newly Generated Neurons: When Time Matters
Authors: Mouret Aurélie , Gheusi Gilles , Gabellec Marie-Madeleine , de Chaumont Fabrice , Olivo-Marin Jean-Christophe , Lledo Pierre-Marie
Published: November 2008

New interneurons are continually added to the olfactory bulb (OB), the first central relay for processing olfactory information, throughout life. It remains unknown how these adult-generated interneurons integrate into preexisting networks or die. We used immunohistochemical approaches to quantify adult neurogenesis in mice subjected to olfactory training. We identified a critical period in the life of an adult-generated OB interneuron, during which learning triggers distinct consequences. Using a discrimination learning task performed at various times after the birth of new interneurons, we found that olfactory training could increase, decrease, or have no effect on the number of surviving newly generated neurons. Cell survival and elimination depend on both the age of the cell and its location within the granule cell layer. This study provides new insight into the contribution of the newly generated interneurons to OB function. It demonstrates that neuronal elimination is an active process, rather than a simple consequence of nonuse.
Oxytocin Enhances Cranial Visceral Afferent Synaptic Transmission to the Solitary Tract Nucleus
Authors: Peters James H. , McDougall Stuart J. , Kellett Daniel O. , Jordan David , Llewellyn-Smith Ida J. , Andresen Michael C.
Published: November 2008

Cranial visceral afferents travel via the solitary tract (ST) to contact neurons within the ST nucleus (NTS) and activate homeostatic reflexes. Hypothalamic projections from the paraventricular nucleus (PVN) release oxytocin (OT) to modulate visceral afferent communication with NTS neurons. However, the cellular mechanisms through which OT acts are poorly understood. Here, we electrophysiologically identified second-order NTS neurons in horizontal brainstem slices by their low-jitter, ST-evoked glutamatergic EPSCs. OT increased the frequency of miniature EPSCs in half of the NTS second-order neurons (13/24) but did not alter event kinetics or amplitudes. These actions were blocked by a selective OT receptor antagonist. OT increased the amplitude of ST-evoked EPSCs with no effect on event kinetics. Variance–mean analysis of ST-evoked EPSCs indicated OT selectively increased the release probability of glutamate from the ST afferent terminals. In OT-sensitive neurons, OT evoked an inward holding current and increased input resistance. The OT-sensitive current reversed at the K+equilibrium potential. Inin vivostudies, NTS neurons excited by vagal cardiopulmonary afferents were juxtacellularly labeled with Neurobiotin and sections were stained to show filled neurons and OT-immunoreactive axons. Half of these physiologically characterized neurons (5/10) showed close appositions by OT fibers consistent with synaptic contacts. Electron microscopy of medial NTS found immunoreactive OT within synaptic boutons. Together, these findings suggest that OT released from PVN axons acts on a subset of second-order neurons within medial NTS to enhance visceral afferent transmission via presynaptic and postsynaptic mechanisms.
Night Blindness and the Mechanism of Constitutive Signaling of Mutant G90D Rhodopsin
Authors: Dizhoor Alexander M. , Woodruff Michael L. , Olshevskaya Elena V. , Cilluffo Marianne C. , Cornwall M. Carter , Sieving Paul A. , Fain Gordon L.
Published: November 2008

The G90D rhodopsin mutation is known to produce congenital night blindness in humans. This mutation produces a similar condition in mice, because rods of animals heterozygous (D+) or homozygous (D+/+) for this mutation have decreased dark current and sensitivity, reduced Ca2+, and accelerated values of τRECand τD, similar to light-adapted wild-type (WT) rods. Our experiments indicate that G90D pigment activates the cascade, producing an equivalent background light of ∼130 Rh* rod−1for D+ and 890 Rh* rod−1for D+/+. The active species of the G90D pigment could be unregenerated G90D opsin or G90D rhodopsin, either spontaneously activated (as Rh*) or in some other form. Addition of 11-cis-retinal in lipid vesicles, which produces regeneration of both WT and G90D opsin in intact rods and ROS membranes, had no effect on the waveform or sensitivity of dark-adapted G90D responses, indicating that the active species is not G90D opsin. The noise spectra of dark-adapted G90D and WT rods are similar, and the G90D noise variance is much less than of a WT rod exposed to background light of about the same intensity as the G90D equivalent light, indicating that Rh* is not the active species. We hypothesize that G90D rhodopsin undergoes spontaneous changes in molecular conformation which activate the transduction cascade with low gain. Our experiments provide the first indication that a mutant form of the rhodopsin molecule bound to its 11-cis-chromophore can stimulate the visual cascade spontaneously at a rate large enough to produce visual dysfunction.
A TRLFS study of Cm(III) hydroxide complexes in alkaline CaCl2solutions
Authors: Rabung Thomas , Altmaier Marcus , Neck Volker , Fanghänel Thomas
Published: November 2008

Time-resolved laser fluorescence spectroscopy (TRLFS) is used to study Cm(III) solutions ([Cm]tot=2×10−7 M) in 0.1−3.5 M CaCl2at pHc≈11.7 and in three sets of experiments at constant ionic strength (1.0, 2.5 and 3.5 M CaCl2) with pHcvarying from 10.8 to 11.9. The fluorescence spectra show Cm(III) emission bands in the range 605−620 nm. Increasing the CaCl2concentration strongly enhances the intensity of the observed bands. The concentration of aqueous Cm(III) species determined after 10 kD ultrafiltration increases as well, indicating that the Cm(III) hydroxide complexes are stabilized by a strong interaction with Ca2+ions. In 5 M NaCl-NaOH solutions studied for comparison, the curium is almost completely precipitated as Cm(OH)3colloids which show no fluorescence emission bands.

Peak deconvolution and the evaluation of the pH dependence of the spectroscopic data show that three emission bands with λmax=607.5, 609.9 and 614.7 nm come from Cm(III) complexes with three, four and six OH−ligands, respectively. The tri- and tetrahydroxide complexes are dominant in 0.1−1.0 M CaCl2, the hexahydroxide complex dominates at higher CaCl2concentrations and pHc>11.5. As a consequence of the strong dependence on the Ca2+concentration and the absence of these complexes in NaOH-NaCl solutions, thermodynamic modelling of the apparent equilibrium constants for stepwise complex formation and the solubility of colloidal Cm(OH)3(am) requires that the observed species are treated as ternary Ca−Cm(III)−OH complexes: Cax[Cm(OH)3]2x, Cay[Cm(OH)4]2y−1and Caz[Cm(OH)6]2z−3wherexmay be 0 or 1,y=2 andz=3.
Structural investigation of coprecipitation of technetium-99 with iron phases
Authors: Alliot Llorens I. , Deniard Philippe , Gautron E. , Olicard A. , Fattahi Massoud , Jobic Stéphane , Grambow Bernd
Published: November 2008

Technetium is a long-lived product of nuclear fission which commonly exhibits two oxidation states (IV and VII). Siderite (FeCO3), suspected to be formed as a container corrosion product in geological radioactive waste repositories, may concentrate by coprecipitation more than 90% of technetium-99, present as Tc(IV) in surrounding aqueous fluids. X-ray diffraction and transmission electron microscopy measurements indicate that technetium can be incorporated within the siderite structure, even if we note that technetium-bearing green rust phase may also be observed. These results suggest that siderite might play a beneficial role in limiting Tc diffusion to the next environment of nuclear waste repositories.
Leaching of a zirconolite ceramic waste-form under proton and He2+ irradiation
Authors: Tribet M. , Toulhoat N. , Moncoffre N. , Jegou Christophe , Leturcq G. , Corbel C. , Toulhoat P.
Published: November 2008

In the hypothesis of a nuclear waste geological disposal, zirconolite is a candidate host material for minor tri- and tetra-valent actinides arising from enhanced nuclear spent fuel reprocessing and partitioning. Its chemical durability has been studied here under charged particle-induced radiolysis (He2+ and proton external beams) to identify possible effects on dissolution rates and mechanisms in pure water. Two experimental geometries have been used to evaluate the influence of the following parameters: solid irradiation and total deposited energy. Results on the evolution of the elemental releases due to the enhanced dissolution of the zirconolite surface during charged particle-induced irradiation of water are presented. Under radiolysis, elemental releases are first kinetically controlled. When the titanium and the zirconium releases reach (or exceed) their corresponding hydroxide solubility limits, the zirconolite dissolution becomes thermodynamically controlled.
Technetium reduction and reoxidation behaviour in Dounreay soils
Authors: Begg James D. C. , Burke Ian T. , Charnock John M. , Morris Katherine
Published: November 2008

Technetium is a radioactive contaminant found in groundwaters at sites where nuclear wastes have been processed or stored. The redox chemistry of technetium is a major control on its environmental mobility. Under oxic conditions, technetium exists as the pertechnetate ion, Tc(VII)O4
−, which is poorly sorbed by minerals across a wide range of environmentally relevant pH values. Under reducing conditions pertechnetate is converted to lower valency species, of which Tc(IV) tends to predominate. Typically, the Tc(IV) oxidation state readily precipitates as insoluble hydrous Tc(IV) oxides or, at low concentrations, is removed from solution by association with mineral surfaces. Here, we present novel X-ray absorption spectroscopy (XAS) data examining Tc associations with reduced Dounreay soils. In reduced unamended microcosms and in microcosms where we added the co-contaminants ethylenediaminetetraacetic acid (EDTA) or bicarbonate to investigate their effect on Tc biogeochemistry, Tc was removed from solution on exposure to the reduced sediments and was present on solids as hydrous Tc(IV)O2-like phases. Furthermore, to investigate the long term stability and remobilization of solid phase associated Tc in reduced soils, we reoxidized reduced, Tc(IV)-labeled soils, in the presence of air and nitrate. The extent of remobilization of Tc to solution was dependent on the oxidant used. After reoxidation with air for 60 d, (42±6)% of the initial soil bound Tc was resolubilized. In the presence of 25 or 100 mmol L−1 nitrate as an oxidant, negligible microcosm reoxidation or remobilization of Tc to solution occurred. XAS analysis of soils treated with the two oxidants showed that in both systems, the remaining soil associated Tc was present as hydrous TcO2-like phases. The recalcitrance of Tc remobilization under reoxidizing conditions has implications for the fate of Tc in contaminated environments.
Effects of hydrogen and bromide on the corrosion of spent nuclear fuel andγ-irradiated UO2(s) in NaCl brine
Authors: Metz Volker , Loida A. , Bohnert E. , Schild D. , Dardenne Kathy
Published: November 2008

Radiation induced UO2(s) corrosion is studied at elevated hydrogen pressure in NaCl brine containing traces of bromide. Release of Sr, Cs, Tc and actinides was measured in corrosion experiments with spent nuclear fuel pellets in presence of 10−2 mol H2(kg H2O)−1, and 10−4and 10−3 mol Br−(kg H2O)−1, respectively. For comparison, depleted UO2(s) pellets were γ-irradiated in NaCl brine at 10−3 mol H2(kg H2O)−1and 0−10−4 mol Br−(kg H2O)−1, respectively. In the γ-radiolysis experiments a significant increase in the yield of radiolytic products due to Br−is observed. Both, in the γ-radiolysis experiment with Br−and in that without Br−, the UO2(s) sample was oxidized, and the concentration of dissolved uranium was controlled by precipitation of meta-schoepite and clarkeite. In the spent nuclear fuel corrosion experiment under H2overpressure, aqueous concentrations of Tc and Np were in the range of solubilities of Tc(IV) and Np(IV) hydroxides, whereas measured U concentrations were between solubilities of U(VI) and U(IV) phases. The release rate of Sr was significantly increased in the presence of Br−traces. Results of the complementary spent nuclear fuel corrosion andγ-radiolysis experiments allow the conclusion that Br−traces reduce significantly the protective hydrogen effect with respect to the release of certain radionuclides and the yield of radiolytic products.
Measuring sorption coefficients and BET surface areas on intact drillcore and crushed granite samples
Authors: André Magnus , Neretnieks Ivars , Malmström M. E.
Published: November 2008

In general sorption coefficients, K
d, cat ion exchange capacity, CEC, and BET surface areas are measured on crushed rock samples because it is very time consuming to measure K
d and CEC on larger rock pieces as it takes a long time for the sorbing species to penetrate into and equilibrate a large sample. Also conventional sample holders for BET measurements are too small to hold a large sample.

We have manufactured large sample holders for BET measurements and modified the equipment so that it is possible to measure BET surface areas on samples with 50 mm diameter and up to 100 mm length. Results are presented for intact pieces and compared to results on crushed material from the same drillcore.

For K
d and CEC measurements we have developed a technique and equipment by which ions can be made to rapidly intrude into and equilibrate the internal surfaces of the same size samples as mentioned above. The method is based on electro-migration where the sample is placed between two vessels one with an anode and other with a cathode. The electric potential gradient drives the ions into and through the sample very much faster than molecular diffusion does. With Cs as the sorbing ion a few weeks were sufficient to equilibrate the 50 mm long sample. In previous diffusion experiments it took more than a year to equilibrate a 15 mm thick sample. A special mixing technique eliminates the development of low and high pH in the electrode compartments.

K
d results from measurements on an intact drillcore are presented and comparison is made with results obtained on crushed material from the same bore core. The results from the sorption experiments are compared with the results from the BET surface area determinations in an attempt to evaluate the use of the BET surface area as a proxy for sorption behaviour.
The influence of natural organic matter on the speciation and solubility of Eu in Boom Clay porewater
Authors: Liu D. J. , Bruggeman C. , Maes Norbert
Published: November 2008

The influence of natural organic matter (NOM) on the speciation and solubility of europium (Eu) was studied under geochemical conditions representative for the Boom Clay. Different organic matter types were used, and analysis was performed both after 0.45 μm microfiltration and after 30000 MWCO ultrafiltration to distinguish between larger colloids (assumed to be immobile underin situconditions) and small dissolved species.

Equilibrium was approached from undersaturation starting from synthesised Eu(OH)3(s), which, during the experiment, transformed into EuOHCO3(s), in agreement with thermodynamic considerations. In the absence of NOM, the Eu solution concentrations after 0.45 μm filtration exceeded the thermodynamic solubility of EuOHCO3(s) by several orders of magnitude, indicating the presence of inorganic Eu colloids. In the presence of NOM, the Eu solubility increased with increasing NOM concentration as was expected, but, surprisingly, was dependent on the operational size cut-off: at an identical NOM concentration in the filtrate, the Eu solution concentration after 0.45 μm filtration was consistently higher compared to the Eu concentration after 30000 MWCO filtration. This latter observation necessitates detailed knowledge concerning the pore size cut-off of Boom Clay underin situconditions in order to use the correct Eu-NOM complexation constant and/or maximum solubility in transport calculations. At higher NOM concentrations (TOC>30 mg/L) the Eu solubility after 0.45 μm filtration was seemingly independent of the NOM concentration.

In contrast, after 30000 MWCO ultrafiltration, the Eu solution increased linearly with increasing DOC, from the expected thermodynamic solubility (∼5×10−7 mol L−1) at 0 mg L−1DOC to ∼3×10−5 mol L−1at 80 mg L−1DOC. All of the data sets were modelled using the Nagra/PSI database [8] for solubility, hydrolysis and inorganic aqueous complexation reactions, and fitted organic complexation reactions between Eu3+and NOM functional groups. Both a free ligand approach (with electrostatic correction) and the humic ion-binding model VI [23], which was for the first time successfully introduced into Phreeqc geochemical code, were tested and provided equally good fits to the data.
Pu(V) reduction and enhancement of particle-water partitioning by exopolymeric substances
Authors: Roberts Kimberly A. , Santschi Peter H. , Honeyman Bruce D.
Published: November 2008

Central to understanding the environmental behavior of Pu in vadose- and saturated-zones, as well as waste streams, is the contribution of colloidal natural organic mater (NOM), e.g. , biopolymeric exopolymeric substances (EPS) from Pseudomonas fluorescens Biovar II and geopolymeric humic acids (HA), to Pu speciation. Because Pu(V) and Pu(IV) are present in aquatic systems at sub-pM concentrations, many established techniques for chemical speciation and oxidation state determination are not available. However, the two redox states of Pu can be distinguished through their tendency to form colloidal species. Controlled laboratory experiments with low-colloid background solutions of 0.1 M NaClO4 with an inert buffer (Tris) and 5 μm silica particles of high specific surface area (500 m2/g) and small (3 nm) pores investigated the ability of NOM compounds for their binding and redox qualities showed that: 1) Pu(V) and Pu(IV) tracers at pM concentrations could be distinguished by their tendency to bind to colloidal species (≥1 kDa), with binding extent being high for Pu(IV), and low for Pu(V); 2) EPS can significantly enhance particle- (or colloid-) water partition coefficients to silica particles (K
d, K
dc), quickly (1 day) for Pu(IV) and slowly (1 month) for Pu(V); 3) Pu(V), in the presence of EPS and silica particles can become associated with particles and colloids over periods of months, likely indicating reduction; 4) K
d values can be affected by the reaction sequence of tracer addition to the solution containing silica particles and NOM compounds ( e.g. , EPS or HA).
Laser ablation microprobe inductively coupled plasma mass spectrometry study on diffusion of uranium into cement materials
Authors: Sugiyama Daisuke , Chida Taiji , Cowper M. M.
Published: November 2008

The diffusion of uranium (U(VI)) in solid cement monoliths of ordinary portland cement (OPC) and low-heat portland cement containing 30[wt.]% fly ash (FAC) was measured by an in-diffusion technique. Detailed sharp depth profiles of uranium in the solid cement matrices were successively and quantitatively measured using laser ablation microprobe inductively coupled plasma mass spectrometry (LAMP-ICP-MS), and the apparent (D
a) and effective (D
e) diffusion coefficient of uranium in cement matrix were calculated as: D
a=∼4×10−16 m2 s−1 and D
e=∼3×10−11 m2 s−1 for OPC, and D
a=∼2×10−17 m2 s−1 and D
e=∼6×10−13 m2 s−1 for FAC.
Binding of Pu(IV) to galacturonic acid and extracellular polymeric substances (EPS) fromShewanella putrefaciens, Clostridium sp. andPseudomonas fluorescens
Authors: Harper Ruth M. , Kantar Cetin , Honeyman Bruce D.
Published: November 2008

The conditional stability constants for trace-level concentrations of Pu(IV) complexing with galacturonic acid and EPS, isolated from axenicClostridiumsp.,P. fluorescensandShewanella putrefaciensCN32 cultures, were determined at pH 4 and an ionic strength of 0.1 M NaCl using an ion-exchange technique. The analysis of ion-exchange data with Schubert´s technique indicates that the Pu binding by galacturonic acid and EPS fromClostridiumsp. andS. putrefacienscan be described based on the formation of 1:1 Pu(IV)-ligand complexes. However, the accurate description of Pu binding by EPS fromP. fluorescensrequires postulation of a mixture of 1:1/1:2 complexes between Pu(IV) and ligands under the experimental conditions studied.

The results from the ion-exchange experiments were also modeled based on a non-electrostatic, discrete ligand approach in which bacterial EPS is conceptualized as being composed of a suite of monoprotic acids, HLi, of arbitrarily-assigned pKa(i) values (e.g., 4, 6 and 8). The examination of ion-exchange data in a chemical model suggested that only the pKa4 (L1) and 6 (L2) ligands are sufficient to accurately simulate the Pu(IV)/EPS binding, implying that carboxylic groups in EPS are the primary binding sites for complexing with Pu(IV) under the experimental conditions examined. The affinity of EPS for complexing Pu(IV) decreases in the order ofClostridiumsp.>S. putrefaciens>P. fluorescensalthough the concentrations of carboxylic groups in EPS decrease in the order ofP. fluorescens>S. putrefaciens>Clostridiumsp. This discrepancy may be due to differences in binding affinities between Na+ion in solution and EPS ligands. AtI=0.1 M, models demonstrated that the EPS fromP. fluorescensexhibits a much stronger affinity for the Na+ion compared to ligands from other EPS; therefore, the deprotonated carboxylic sites of EPS fromP. fluorescensare hypothesized to be mostly bound by Na+in solution.
The Classical Nuclear Localization Signal Receptor, Importin-α, Is Required for Efficient Transition Through the G1/S Stage of the Cell Cycle inSaccharomyces cerevisiae
Authors: Pulliam Kanika F , Fasken Milo B , McLane Laura M , Pulliam John V , Corbett Anita H
Published: November 2008

There is significant evidence linking nucleocytoplasmic transport to cell cycle control. The budding yeast, Saccharomyces cerevisiae, serves as an ideal model system for studying transport events critical to cell cycle progression because the nuclear envelope remains intact throughout the cell cycle. Previous studies linked the classical nuclear localization signal (cNLS) receptor, importin-α/Srp1, to the G2/M transition of the cell cycle. Here, we utilize two engineered mutants of importin-α/Srp1 with specific molecular defects to explore how protein import affects cell cycle progression. One mutant, Srp1-E402Q, is defective in binding to cNLS cargoes that contain two clusters of basic residues termed a bipartite cNLS. The other mutant, Srp1-55, has defects in release of cNLS cargoes into the nucleus. Consistent with distinct in vivo functional consequences for each of the Srp1 mutants analyzed, we find that overexpression of different nuclear transport factors can suppress the temperature-sensitive growth defects of each mutant. Studies aimed at understanding how each of these mutants affects cell cycle progression reveal a profound defect at the G1 to S phase transition in both srp1-E402Q and srp1-55 mutants as well as a modest G1/S defect in the temperature-sensitive srp1-31 mutant, which was previously implicated in G2/M. We take advantage of the characterized defects in the srp1-E402Q and srp1-55 mutants to predict candidate cargo proteins likely to be affected in these mutants and provide evidence that three of these cargoes, Cdc45, Yox1, and Mcm10, are not efficiently localized to the nucleus in importin-α mutants. These results reveal that the classical nuclear protein import pathway makes important contributions to the G1/S cell cycle transition.
The Joint Effects of Selection and Dominance on the QST − FST Contrast
Authors: Santure Anna W , Wang Jinliang
Published: November 2008

Q ST measures the differentiation of quantitative traits between populations. It is often compared to FST, which measures population differentiation at neutral marker loci due to drift, migration, and mutation. When QST is different from FST, it is usually taken as evidence that selection has either restrained or accelerated the differentiation of the quantitative trait relative to neutral markers. However, a number of other factors such as inbreeding, dominance, and epistasis may also affect the QST − FST contrast. In this study, we examine the effects of dominance, selection, and inbreeding on QST − FST. We compare QST with FST at selected and neutral loci for populations at equilibrium between selection, drift, mutation, and migration using both analytic and simulation approaches. Interestingly, when divergent selection is acting on a locus, inbreeding and dominance generally inflate QST relative to FST when they are both measured at the quantitative locus at equilibrium. As a consequence, dominance is unlikely to hide the signature of divergent selection on the QST − FST contrast. However, although in theory dominance and inbreeding affect the expectation for QST − FST, of most concern is the very large variance in both QST and FST, suggesting that we should be cautious in attributing small differences between QST and FST to selection.
Quantificação de clorofilas em folhas de macieiras 'Royal Gala' e 'Fuji' com métodos ópticos não-destrutivos
Authors: Amarante Cassandro Vidal Talamini do , Steffens Cristiano André , Zanardi Odimar Zanuzo , Alves Erlani de Oliveira
Published: November 2008

O método-padrão para a quantificação de clorofilas em folhas é destrutivo e relativamente demorado. Com o advento dos medidores portáteis, a quantificação de clorofilas tornou-se fácil e rápida, podendo ser realizada de forma não-destrutiva a campo. Colorímetros também podem ser utilizados para a avaliação não-destrutiva da coloração de tecidos vegetais, e, portanto, para a quantificação de clorofilas em folhas. Este trabalho foi conduzido visando a avaliar a viabilidade de utilização de um colorímetro, como alternativa à utilização do medidor portátil de clorofila, para a quantificação não-destrutiva de clorofilas em folhas de macieiras 'Royal Gala' e 'Fuji'. Folhas de ambas as cultivares, com tonalidades variando de verde- amarelada (folha clorótica) a verde-escura, foram avaliadas individualmente, com um medidor de clorofila (Minolta SPAD-502) e um colorímetro (Minolta CR-400, no espaço de cores L, C e hº), seguido de quantificações destrutivas de clorofilas a, b e totais. Os valores das leituras do medidor de clorofila e da relação hº/(LxC) do colorímetro aumentaram com o incremento nos teores de clorofilas nas folhas em macieiras 'Royal Gala' e 'Fuji'. Os modelos ajustados entre os teores de clorofilas e as leituras do medidor de clorofila e da relação hº/(LxC) do colorímetro apresentaram valores similares de R², em ambas as cultivares. Os resultados obtidos demonstram que o colorímetro é uma alternativa viável na avaliação não-destrutiva do teor de clorofilas (µg.cm-2 de folha) em macieiras, especialmente de clorofilas a e totais. Para tanto, os valores da relação hº/(LxC) do colorímetro devem ser previamente calibrados com a extração de clorofilas das folhas da cultivar de interesse.
Acúmulo de antocianinas e características físicas e químicas de frutos de laranjas sanguíneas durante o armazenamento a frio
Authors: Latado Rodrigo Rocha , Tognato Paola Christovam , Silva-Stenico Maria Estela , Nascimento Lenice Magali do , Santos Pedro César dos
Published: November 2008

Este trabalho teve como objetivo avaliar o conteúdo de antocianinas no suco e as características físicas e químicas dos frutos de oito variedades de laranjas sanguíneas e de laranja Valência, e, também, verificar os efeitos do armazenamento dos frutos a 10ºC, durante um período de até 60 dias, nos parâmetros avaliados. Os teores de antocianina foram determinados utilizando-se de um método espectrofotométrico, assim como dez características físicas e químicas dos frutos e dos sucos foram avaliadas antes e durante o armazenamento. Todas as variedades de laranja avaliadas apresentaram naturalmente baixos teores ou nenhum teor de antocianina no suco. O armazenamento durante um período de até 60 dias, em baixa temperatura, possibilitou acúmulo significativo de antocianina no suco, porém de maneira desigual nas variedades de laranjas sanguíneas testadas. As variedades Moro foram as que apresentaram suco contendo os maiores teores de antocianina no final do armazenamento. À exceção de duas variedades, Sanguinelli (Marrocos e Polidari), as demais variedades sanguíneas avaliadas podem ser consideradas como semelhantes entre si e adequadas ao consumo. O armazenamento dos frutos a 10ºC, durante o período máximo de 60 dias, alterou significativamente somente as variáveis: largura de frutos, teor de SS, acidez e o rendimento de suco.
Efeito da poda verde na composição físico-química do mosto da uva Merlot
Authors: Mandelli Francisco , Miele Alberto , Rizzon Luiz Antenor , Zanus Mauro Celso
Published: November 2008

O manejo do dossel vegetativo da videira pode causar modificações na composição e na qualidade da uva e do vinho. Dentre as práticas culturais utilizadas para essa finalidade, destacam-se as relacionadas à poda verde. Nesse sentido, visando a melhorar a qualidade do mosto da uva Merlot, conduziu-se este experimento com diferentes modalidades de poda verde. O trabalho foi realizado de 1993/1994 a 1996/1997, num vinhedo conduzido em latada. Houve 12 tratamentos e três repetições, sendo o delineamento experimental em blocos casualizados. Os tratamentos constituíram-se da testemunha e de 11 diferentes modalidades de poda verde, i.e., desbrota, desponta e desfolha, algumas delas em diferentes épocas do ciclo vegetativo da videira. Os resultados mostram que houve variação de ano para ano, mas, considerando a média dos quatro anos de avaliação, constatou-se que os tratamentos 10 (desbrota + desponta + desfolha realizada no início da floração e eliminando todas as folhas abaixo dos cachos) e 9 (desbrota + desfolha realizada 21 dias antes da colheita e eliminando metade das folhas abaixo dos cachos) proporcionaram maior síntese e acúmulo de açúcar na uva, o que é expresso pelo ºBrix e pela densidade, e menor de acidez, expressa pelos ácidos tartárico e málico, pH e acidez titulável. Num segundo plano, mas ainda eficientes, citam-se os tratamentos 11 (desbrota + desponta + desfolha realizada 21 dias antes da colheita e eliminando metade das folhas abaixo dos cachos), 2 (desponta) e 3 (desfolha no início da floração e eliminando todas as folhas abaixo dos cachos).
Caracterização molecular de butiazeiro por marcadores RAPD
Authors: Nunes Adrise Medeiros , Bianchi Valmor João , Fachinello José Carlos , Carvalho Alexandre Zanardo de , Cardoso Guilherme
Published: November 2008

O grupo botânico Arecaceae é de extremo interesse por compreender plantas em extinção e por apresentar um grande potencial de exploração econômica. O butiazeiro (Butia capitata (Mart.) Becc.) ocorre naturalmente no Sul do Brasil. Sua caracterização molecular é de extremo interesse para futuros trabalhos de melhoramento genético. Assim sendo, verificou-se a variabilidade genética existente entre vinte e dois genótipos de butiazeiro da espécie (Butia capitata), pertencentes ao BAG (Banco Ativo de Germoplasma) de frutíferas nativas do Centro Agropecuário da Palma - UFPel. Esses genótipos foram analisados usando marcadores do tipo RAPD (Random Amplified Polymorphic DNA). Um total de 136 fragmentos foram obtidos, sendo 77 polimórficos. O primer OPA11 apresentou maior polimorfismo, produzindo 9 perfis diferentes. A análise de agrupamento, realizada pelo método UPGMA, produziu um dendrograma que permitiu a clara separação dos genótipos em dois grupos principais. Verificou-se que, com a técnica de marcadores de RAPD, foi possível obter um perfil molecular único e uma estimativa da variabilidade existente entre os genótipos de butiazeiro avaliados.
Viabilidade da utilização de descartes de produção de uvas sem sementes para elaboração de passas
Authors: Feldberg Nelson Pires , Mota Renata Vieira da , Simões Welson Lima , Regina Murillo de Albuquerque
Published: November 2008

A região do Vale do São Francisco destaca-se na produção de uvas de mesa, com incrementos cada vez maiores na produção de cultivares sem sementes. A fim de evitar perdas e aumentar a renda do produtor, torna-se necessário o desenvolvimento de tecnologias para o aproveitamento do excedente da produção de forma economicamente viável. Considerando-se a dependência do Brasil ao mercado externo em uva-passa, este trabalho teve como objetivo avaliar a viabilidade da elaboração de passas a partir das cultivares sem sementes Sultanina, Catalunha, Superior Seedless e Crimson Seedless produzidas no norte de Minas Gerais. As passas foram analisadas quanto ao teor de umidade, sólidos solúveis totais (SST), acidez total titulável (ATT), pH, açúcares redutores e diâmetros longitudinal e transversal, e os resultados, comparados com o produto chileno adquirido no comércio local. As passas das cultivares produzidas nesta região apresentaram maior tamanho e composição semelhante ao produto importado. As passas de 'Crimson Seedless' apresentaram teor significativamente maior de umidade após 20h de secagem, enquanto Catalunha e Sultanina se destacaram quanto aos teores de SST, ATT e açúcares redutores. Os resultados obtidos indicam que a produção de passas é viável tecnicamente, porém trabalhos complementares são necessários para avaliar a viabilidade econômica deste processo.
Management of crotalaria and pigeon pea for control of yam nematode diseases
Authors: Garrido Marlon da Silva , Soares Ana Cristina Fechino , Coimbra João Luiz , Sousa Carla da Silva
Published: November 2008

Management of plant-parasitic nematodes with the use of nematicides has not been recommended for small farmers that grow yam in the Northeastern region of Brazil, due to its high cost and residue toxicity. The use of plants with antagonistic effect to nematodes and green manure which improves soil chemical, physical and biological characteristics can be a viable and low cost alternative to control parasitic nematodes. This work aimed to evaluate the effect of crotalaria (Crotalaria juncea) and pigeon pea (Cajanus cajan) plants on the control of yam nematodes. Three experiments were carried out. The first was conducted under in vitro conditions to evaluate the nematostatic and nematicide effect of extracts from fresh and dry matter of the above ground parts of crotalaria, pigeon pea, and the combination of both. The second experiment was carried out under greenhouse conditions to evaluate the effect of soil amendment with crotalaria, pigeon pea, and the combination of both in the infectivity of Scutellonema bradys, using tomato plants as the host plant. The third experiment was conducted under field conditions to evaluate the effect of crotalaria, pigeon pea, and the combination of both, cultivated between yam planting rows and incorporated to soil surface, on yam nematodes. The aqueous extract obtained form fresh matter of crotalaria had a nematicide effect of 100% for S. bradys. Extracts from dry matter of both crotalaria and pigeon pea did not have any nematicide effect, but had a nematostatic effect. Incorporation of crotalaria to soil inhibited infectivity of S. bradys in tomato seedlings. These results showed that planting crotalaria alone or in combination with pigeon pea, between the yam planting rows, is an efficient method for controlling S. bradys and Rotylenchulus reniformis associated with yams. Crotalaria can be used for controlling these plant-parasitic nematodes in soil.