bluuebunny/crossref_metadata_2025_split huggingface dataset:
On the Fate of Vanadate in Human Blood
Authors: Gorzsás András , Andersson Ingegärd , Pettersson Lage 
Published: July 2006

AbstractAs a summary of recent activities at our research group, a model describing the distribution of pentavalent vanadium (referred to as vanadate throughout the present work) in human blood has been constructed based on our speciation studies performed in the physiological medium of 0.150 M Na(Cl) with various blood constituents. In addition, other data (most notably with the high mass serum constituents albumin and transferrin) have also been used to give as broad a view as possible. Two antidiabetic drug candidate ligands, picolinate and maltol, have also been included in order to investigate the stability of their vanadium complexes in the presence of blood constituents, i.e. to account for ligand‐exchange possibilities. The model predicts transferrin to be the major carrier of vanadium in the bloodstream. It is capable of almost completely replacing the vanadium‐bound picolinate even if the latter is in large excess. Maltol, on the other hand, can retain most of the vanadium when it is supplied in about a 5 mM concentration. The model still has certain limitations but it serves as a useful base for investigating structure, stability, relationship effects and provides insight into the fate of vanadate in human blood.(© Wiley‐VCH Verlag GmbH & Co. KGaA, 69451 Weinheim, Germany, 2006)
Actinide‐Transition Metal Heteronuclear Ions and Their Oxides: {IrUO}+ as an Analogue to Uranyl
Authors: Santos Marta , Marçalo Joaquim , Pires de Matos António , Gibson John K. , Haire Richard G. 
Published: July 2006

AbstractRecent theoretical calculations have shown that Ir should behave as a chemical analogue to N, with the result that IrUO+, like known NUO+, is predicted to be a stable species isoelectronic with UO22+, the uranyl dication. The target heterometallic analogue to uranyl has now been prepared by direct laser desorption/ionization of a U/Ir alloy, and by oxidation of UIr+ with N2O and C2H4O. Properties of UIr+, UPt+, and UAu+ bimetallic ions have been studied. They demonstrate direct actinide–transition metal bonding, and support the concept of “autogenic isolobality”. (© Wiley‐VCH Verlag GmbH & Co. KGaA, 69451 Weinheim, Germany, 2006)
Thermal Rearrangements of Heteroatom‐Bridged Diallenes
Authors: Bui Binh H. , Schreiner Peter R. 
Published: July 2006

AbstractA systematic application of the BLYP/6‐311+G*//BLYP/6‐31G* computational scheme was utilized to identify the favored aromatic 2,6‐reactions leading to the formally aromatic hetero‐3,4‐dimethylenecyclopentadienediyl derivatives from the thermal rearrangements of (hetero)atom‐bridged diallenes (X = CH–, NH, O, S). Protonation of the heteroatom substituent raises the respective 2,6‐cyclization energybarrier, and the alternative 1,6‐cyclization reaction forming the hetero‐cyclohexadienediyl can compete.(© Wiley‐VCH Verlag GmbH & Co. KGaA, 69451 Weinheim, Germany, 2006)
Enantioselective aptameric molecular recognition material: Design of a novel chiral stationary phase for enantioseparation of a series of chiral herbicides by capillary electrochromatography
Authors: André Claire , Berthelot Alain , Thomassin Mireille , Guillaume Yves‐Claude 
Published: July 2006

AbstractA chiral stationary phase derived from an L‐RNA aptamer is evaluated for the enantiomer separation of a series of herbicide molecules (aryloxypropionic, aryloxyphenoxypropionic, and aminopropionic acid) by CEC after binding to biotin and grafting upon streptavidin‐modified porous glass beads. We demonstrated that the aptamer capillary was stable in term of efficiency and retention during a long period. The influences of the mobile phase constitution and its flow‐velocity on the enantioseparation were also investigated. The results suggest that the interactions of the enantiomer during CEC are solely based on chromatographic mechanisms and that the electrophoresis plays only a minor role. The separation efficiency and peak shape could be improved by Mg2+ divalent cation that stabilized the aptamer secondary structure and thus enhanced the mass transfer kinetics during the ligand‐aptamer binding process. In addition, it was demonstrated that the determination of the enantiomerization barrier of flamprop was possible using this chiral stationary phase.
In‐capillary solid‐phase extraction–capillary electrophoresis for the determination of chlorophenols in water
Authors: Zhang Luo‐Hong , Zhang Cheng‐Jie , Chen Xueming , Feng Yu‐Qi , Wu Xing‐Zheng 
Published: July 2006

AbstractA novel CE method combined with SPE in a single capillary was developed for analysis of chlorophenols in water. A frit of 0.5 mm was first made by a sol‐gel method, followed by packing a SPE sorbent in the inlet end of the capillary. Two phenol derivatives, 2,4‐dichlorophenol and 2,4,5‐trichlorophenol, were used as the model compounds. By loading sample solutions into the capillary, the two chlorophenols were extracted into the sorbent. They were desorbed by injecting only about 4 nL of methanol. Finally, the analytes were separated by conventional CE. The technique provided a concentration enhancement factor of over 4000‐fold for both chlorophenols. The detection limits (S/N = 3) of 2,4‐dichlorophenol and 2,4,5‐trichlorophenol were determined to be 0.1 ng/mL and 0.07 ng/mL, respectively. For replicate analyses of 5 ng/mL of 2,4‐dichlorophenol, within‐day and between‐day RSDs of migration time, peak height and peak area were in the range of 1.8–2.0%, 4.0–4.4% and 4.1–4.6%, respectively. The method shows wide linear range, acceptable reproducibility and excellent sensitivity, and it was applied to the analyses of spiked river water samples. The capillary packed with the SPE sorbents can be used for more than 400 runs without performance deterioration.
Evidence for freeze–thaw events and their implications for rock weathering in northern Canada: II. The temperature at which water freezes in rock
Authors: Hall Kevin 
Published: July 2006

AbstractMany undertakings have used either a single value or a narrow window of temperatures as a threshold for the freezing of water within rock. These temperatures vary from 0 to −5 C, with most windows being in the range −1 to −4 C. Based on thermal data, these thresholds are commonly used to ‘count’ the number of freeze–thaw events as a basis for determining freeze–thaw weathering. Data collected from northern Canada indicate that the temperature at which freezing occurs can vary substantially, even for the same site. Using exotherm and zero curtain observations from bricks, at angles of 90 and 45, aligned to the four cardinal aspects, the various temperatures at which water froze are shown. Bricks on the north and east commonly did exhibit freezing, based on exotherms, within the window −1 to −5 C, while data for the south and west aspects showed substantial variation, with freezes sometimes between −6·4 and −8·9 C. The data were evaluated for evidence of zero curtain effects (indicative of water freezing), but no unequivocal events could be found, and it is suggested that, at the scale of observation used here, they are unlikely. It would therefore appear that the use of thermal thresholds may not be meaningful for evaluation of freeze–thaw events. The available data also indicate many instances when temperatures went substantially sub‐zero (e.g. −20 C) and yet no indication of water freezing occurred – most likely because there was no water available to freeze. This indicates that any form of freeze–thaw event counting, in the absence of some indicator of the presence of water and that it actually froze, is flawed, as thermal conditions alone are not adequate to indicate the occurrence or not of actual freeze–thaw weathering events. These data suggest that evaluations of freeze–thaw occurrence based simply on thermal thresholds may be substantially in error. Copyright © 2006 John Wiley & Sons, Ltd.
Export of organic carbon in run‐off from an Amazonian rainforest blackwater catchment
Authors: Waterloo Maarten J. , Oliveira Sylvia M. , Drucker Debora P. , Nobre Antonio D. , Cuartas Luz A. , Hodnett Martin G. , Langedijk Ivar , Jans Wilma W. P. , Tomasella Javier , de Araújo Alessandro C. , Pimentel Tania P. , Múnera Estrada Juan C. 
Published: July 2006

AbstractRainfall, run‐off and dissolved and particulate organic carbon concentrations were measured to investigate the hydrological export of organic carbon out of the blackwater Igarapé Asu rainforest catchment over a two‐year period. Annual rainfall was above average (2442 mm) at 2976 mm in 2002 and below average at 2054 mm in 2003. Surface run‐off dominated the flow out of the catchment, with groundwater outflow being negligible. Streamflow totals amounted to 1362 mm in 2002 and 780 mm in 2003. Dissolved organic carbon (DOC) concentrations in rainfall were similar to those measured in rainfall elsewhere in the Amazon Basin at 1·2 mg l−1, leading to atmospheric DOC deposition estimates of 3·5 g m−2 in 2002 and 2·4 g m−2 in 2003. Daily average DOC concentrations in run‐off ranged from 8 mg l−1 under low flow conditions to 27 mg l−1 during large quickflow events. Suspended sediment (10–2000‐µm size fraction) consisted for 28% of carbon and had a median concentration of 4·1 mg l−1. Daily run‐off varied between 1·2–2·5 mm day−1 during dry periods with corresponding organic carbon exports of 0·009–0·031 g m−2 day−1. Exports associated with large storms were much higher, reaching a daily maximum of 1·02 g m−2 day−1 for a discharge event of 38·4 mm. Export of carbon during the wet seasons amounted to 70% of the total. Annual exports in river water were different between the years because of differences in run‐off, varying between 26·2 g C m−2 in 2002 and 11·7 g C m−2 in 2003. Organic carbon exports were dominated by DOC, with exports in sediment constituting 6–8% of the total. Net carbon export, corrected for rainfall inputs, amounted to 22·7 and 9·3 g m−2 in 2002 and 2003, respectively. The present study indicates that accounting for exports of organic carbon in stream run‐off (averaging 19·0 g m−2 year−1 over the 2 years) would reduce the rainforest sink strength, estimated at 300–400 g m−2 year−1 from eddy covariance measurements, by 5–6% for this blackwater catchment. Copyright © 2006 John Wiley & Sons, Ltd.
Organic carbon fluxes within and streamwater exports from headwater catchments in the southern Amazon
Authors: Johnson Mark S. , Lehmann Johannes , Selva Evandro Carlos , Abdo Mara , Riha Susan , Couto Eduardo Guimarães 
Published: July 2006

AbstractForms and quantities of organic carbon (C) fluxes at the soil surface, and organic C exports from four small (1–2 ha) headwater catchments were quantified and contrasted in the seasonally dry southern Amazon for 1 year to compare C fluxes within the terrestrial ecosystem with exports to the aquatic ecosystem. At the soil surface, the flux of litterfall C was 43 times greater than the dissolved organic carbon (DOC) flux in throughfall, with the highest rates of C deposition during the dry season. The form and timing of organic C was reversed for watershed exports, where DOC comprised 59% of the annual total organic C export, and exports were greatest during the 4‐month rainy season (63% of total annual exports). Fine particulate organic carbon (FPOC) in streamwater was a substantially larger flux than coarse particulate organic carbon (CPOC), representing 37 and 4% of total annual organic C exports, respectively. Particulate organic C exports exhibited substantial seasonal variability, with FPOC and CPOC mobilized primarily in the rainy season and strongly connected to storm events. Storm flow comprised 6% of total streamflow for the year studied, and 10% of streamflow during the rainy season. In the rainy season, over 90% of FPOC exports were transported by storm flow, while only 32% of DOC exports were exported by storm flow during this period. Streamwater DOC concentrations were found to increase linearly with increasing terrestrial litterfall during the dry season (r2 = 0·92, p < 0·001), indicating that in‐stream processing of allochthonous litterfall is an important source of DOC during the dry season. Copyright © 2006 John Wiley & Sons, Ltd.
A modified technique for the impregnation of lanthanum tracer to study the integrity of tight junctions on cells grown on a permeable substrate
Authors: Nilsson Harriet , Dragomir Anca , Ahlander Anders , Ljungkvist Marianne , Roomans Godfried M. 
Published: July 2006

AbstractIonic lanthanum is commonly used to trace permeability pathways across epithelia and endothelia in biological electron microscopy. A method for obtaining a uniformly dense precipitate of lanthanum is described. The method, which is a modification of the technique described by Shaklai and Tavassoli (1977) was suitable for fixation of cell cultures grown on permeable filter inserts and was successfully applied to study opening of tight junctions by hypertonic solutions in the airway epithelial cell line 16HBE14o−. The preparation method formed the basis for a semiquantitative morphological determination in which the tight junctions were subdivided as “intact,” “weakened,” and “open.” By using this modified technique, it could be demonstrated that opening of tight junctions in airway epithelial cells increased, with increasing osmolarity with electrolytes having a stronger effect than nonelectrolytes. A significant linear relationship was found between the osmolarity of the medium and the open state of the tight junctions (as determined by the semiquantitative morphological technique) or the transepithelial electrical resistance. Microsc. Res. Tech., 2006. © 2006 Wiley‐Liss, Inc.
Aid, restitution and international fiscal redistribution in health care: implications of health professionals' migration
Authors: Mackintosh Maureen , Mensah Kwadwo , Henry Leroi , Rowson Michael 
Published: July 2006

AbstractHigh and sustained levels of migration of health professionals from labour‐short health services in low‐income countries to the health services of rich countries create a perverse subsidy from poor to rich, flowing across national boundaries. This subsidy worsens international inequality, and creates an obligation, both ethical and legal, for the payment of restitution. Drawing on the case of the migration of health professionals from Sub‐Saharan Africa to the UK, we argue that this obligation in turn constitutes an opportunity to shift development aid relationships away from a framework of charity towards a less neo‐colonial commitment to progressive international fiscal transfers. Copyright © 2006 John Wiley & Sons, Ltd.
Residential responses to fear (of crime plus) in two Cape Town suburbs: implications for the post‐apartheid city
Authors: Lemanski Charlotte 
Published: July 2006

AbstractThis article addresses citizens' physical and emotional responses to fear (of crime plus) in post‐apartheid urban South Africa. Using primary research undertaken in two Cape Town residential suburbs, the impact of fear on citizens' lifestyle choices is demonstrated. In the first suburb the response to fear manifests in the immense physical security of a gated community, while residents of the second suburb have created an ‘Improvement District’ in order to ‘upgrade’ their residential area. Although markedly different responses to crime (and its associated fear), citizen responses in both suburbs focus on displacing both crime and individuals elsewhere, predominately into socio‐economically weaker areas. Both gated communities and improvement districts also create exclusionary spaces that thwart the post‐apartheid drive for integration and desegregation. Copyright © 2006 John Wiley & Sons, Ltd.
Divides and rules: the impact of new wave technologies on learning and innovation in the South
Authors: Mytelka Lynn K. 
Published: July 2006

AbstractAccess to knowledge and the opportunities and capacities needed to innovate are now key to competitiveness in a broad range of ‘traditional’ industries. With the emergence of ‘new wave technologies’, such as biotechnology, that are science based, research and patent intensive, strengthening the knowledge base and linking it to users is all the more critical. New international rules do not make this task any easier and for most developing countries technological divides and knowledge gaps have emerged in rapid succession as they struggle to deal with the challenges to which new wave technologies are giving rise. To avoid further exclusion, high priority must be given to the indigenisation of learning and innovation processes in the South. Copyright © 2006 John Wiley & Sons, Ltd.
IT‐based government reform initiatives in the Indian state of Gujarat
Authors: Madon Shirin 
Published: July 2006

AbstractIT‐based government reform projects form an integral part of policy‐making. These projects include a variety of different types of applications, each of which has a different scope and rationality according to what type of governemt reform is intended. Looking back over a 17‐year period, the author describes the evolution of IT‐based government reform initiatives in the Indian state of Gujarat. The findings reveal the interrelatedness of back‐end and front‐end IT‐based government reform initiatives and provide insights into the kinds of institutional support and activities required in order for these initiatives to lead to governance reform. Copyright © 2006 John Wiley & Sons, Ltd.
The next economy: from dead carbon to living carbon
Authors: Morris David 
Published: July 2006

AbstractIn the early part of the 19th century, the global economy was largely based on carbon extracted directly or indirectly (via animals) from plants. The infant science of chemistry distinguished between products made from vegetables and those made from minerals, in effect, distinguishing between living carbon and dead carbon. By the mid 19th century, however, chemists had adopted a different terminology. Both dead carbon and living carbon, from that time, were lumped together as organic. During the next century the hydrocarbon displaced the carbohydrate as the fundamental building block of industrial societies. But at the dawn of the 21st century, a combination of technological, resource and political developments encouraged a renewed distinction between living and dead carbon and the emergence of a new carbohydrate economy. Copyright © 2006 Society of Chemical Industry
Recent trends in the lipid‐based nanoencapsulation of antioxidants and their role in foods
Authors: Mozafari M Reza , Flanagan John , Matia‐Merino Lara , Awati Ajay , Omri Abdelwahab , Suntres Zacharias E , Singh Harjinder 
Published: July 2006

AbstractAntioxidants may be utilised for two main purposes, to protect the sensory and nutritive quality of the food and/or to protect the body against chronic and age‐related diseases. Generally, antioxidants are subject to process degradation and, when given to the body in their free form, cannot pass cell membranes and are rapidly cleared from the general circulation. Because of their unique properties, lipid‐based nanoencapsulation systems enhance the performance of antioxidants by improving their solubility and bioavailability, in vitro and in vivo stability, and preventing their unwanted interactions with other food components. This paper reviews nanoliposomes, archaeosomes and nanocochleates with respect to their potential applications as antioxidant carriers in foods. Copyright © 2006 Society of Chemical Industry
Polymer Reaction Engineering VI Halifax, Canada May 21–26, 2006
Authors: Hutchinson Robin 
Published: July 2006

AbstractConference Reports: This section contains reports on topical conferences. Reports are usually written at the request of the editorial office, but unsolicited contributions are also welcome. Suggestions should be sent to the editorial office of the Macromolecular journals, preferably by E‐mail to macromol@wiley‐vch.de.
Preparation of 5‐Fluorouracil‐Poly(L‐lactide) Microparticles Using Solution‐Enhanced Dispersion by Supercritical CO2
Authors: Chen Ai‐Zheng , Pu Xi‐Ming , Kang Yun‐Qing , Liao Li , Yao Ya‐Dong , Yin Guang‐Fu 
Published: July 2006

AbstractSummary: 5‐Fluorouracil‐poly(L‐lactide) (5‐Fu‐PLLA) microparticles have been prepared by an SEDS process. First, the 5‐Fu is successfully micronized and is then used to produce the 5‐Fu‐PLLA microparticles. The 5‐Fu‐PLLA microparticles synthesized by the SEDS process exhibit a rather spherical shape and a narrow particle size distribution, where it ranges from 615 to 1 990 nm, with a mean particle size of 980 nm. The dichloromethane residue in the 5‐Fu‐PLLA microparticles without any further treatment is 46 ppm. The average drug load and encapsulation efficiency of the 5‐Fu‐PLLA microparticles are 3.05 and 17.8%, respectively. The rate of drug release from the 5‐Fu‐PLLA microparticles shows mainly first‐order kinetics.Scanning electron spectroscopy image of 5‐Fu‐PLLA microparticles.magnified imageScanning electron spectroscopy image of 5‐Fu‐PLLA microparticles.
A Mechanistic Interpretation of Initialization Processes in RAFT‐Mediated Polymerization
Authors: McLeary James B. , Tonge Matthew P. , Klumperman Bert 
Published: July 2006

AbstractSummary: The presence of strong chain length selectivity behavior during initialization in the RAFT process is an experimental observation. The mechanistic underpinning of the observation is, however, open to interpretation. The rates and concentration profiles for the cyanoisopropyl‐dithiobenzoate‐mediated polymerization of styrene at 70 °C can be relatively well reproduced by either the slow fragmentation or intermediate radical termination models. The use of modeling that provides a fit to the data is an important tool, but should be considered as additional evidence in support of experimental data rather than as experimental evidence in and of itself.Comparison of the time dependencies of the concentrations of AD, AMD, and AM2D by PREDICI modeling for the cyanoisopropyl‐mediated polymerization of styrene at 70 °C generated by the IRT model (lines) versus experimental data.magnified imageComparison of the time dependencies of the concentrations of AD, AMD, and AM2D by PREDICI modeling for the cyanoisopropyl‐mediated polymerization of styrene at 70 °C generated by the IRT model (lines) versus experimental data.
Fertilization induced changes in sea urchin sperm: Mitochondrial deformation and phosphatidylserine exposure
Authors: Kazama Makoto , Asami Kouichi , Hino Akiya 
Published: July 2006

AbstractThis study demonstrates that the single mitochondrion of the sea urchin sperm undergoes a shape change at fertilization that is linked to respiration. The mitochondrion swells and shifts to the lateral side of the sperm head on contact with the homologous egg jelly or egg surface; Mg2+‐ or Na+‐free seawater or respiratory inhibitors also induce this change. During the mitochondrial deformation, the sperm decreases the rate of oxygen consumption and their redox‐state of cytochromes is disrupted b–c1/c. Simultaneously, the adenine nucleotides content changes precipitously. This suggests that mitochondrial morphology is strongly associated with respiratory activities in the sea urchin sperm. These changes in mitochondrial morphology and function are similar to the mitochondrial changes in apoptotic cells such as swelling, decrease in its membrane potential, and release of cytochrome c. In apoptotic cells, the exposure of phosphatidylserine from the inner to outer leaflet of the plasma membrane is one of prominence phenomena. This change was visualized by staining the sea urchin sperm with Annexin V‐Fluorescein. It is possible that mitochondrial deformation is an initial sign of sperm destruction, which like as apoptotic cells. Mol. Reprod. Dev. © 2006 Wiley‐Liss, Inc.