bluuebunny/crossref_metadata_2025_split huggingface dataset:
Four primordial immunoglobulin light chain isotypes, including λ and κ, identified in the most primitive living jawed vertebrates
Authors: Criscitiello Michael F. , Flajnik Martin F. 
Published: September 2007

AbstractThe discovery of a fourth immunoglobulin (Ig) light (L) chain isotype in sharks has revealed the origins and natural history of all vertebrate L chains. Phylogenetic comparisons have established orthology between this new shark L chain and the unique Xenopus L chain isotype σ. More importantly, inclusion of this new L chain family in phylogenetic analyses showed that all vertebrate L chains can be categorized into four ancestral clans originating prior to the emergence of cartilaginous fish: one restricted to elasmobranchs (σ‐cart/type I), one found in all cold‐blooded vertebrates (σ/teleost type 2/elasmobranch type IV), one in all groups except bony fish (λ/elasmobranch type II), and one in all groups except birds (κ/elasmobranch type III/teleost type 1 and 3). All four of these primordial L chain isotypes (σ, σ‐cart, λ and κ) have maintained separate V region identities since their emergence at least 450 million years ago, suggestive of an ancient physiological distinction of the L chains. We suggest that, based upon unique, discrete sizes of complementarity determining regions 1 and 2 and other features of the V region sequences, the different L chain isotypes arose to provide different functional conformations in the Ig binding site when they pair with heavy chains.
Olefin Complexes of Low‐Valent Rhenium
Authors: Choualeb Aldjia , Blacque Olivier , Schmalle Helmut W. , Fox Thomas , Hiltebrand Thomas , Berke Heinz 
Published: October 2007

AbstractReplacement of the MeCN group in the acetonitrile‐cis‐dibromo(nitrosyl)‐trans‐bis(phosphane)rhenium compounds 1a,b (R = iPr a, R = Cy b) with ethylene afforded the olefin derivatives [Re(η2‐H2C=CH2)(NO)(PR3)2Br2] (2a,b) (R = iPr a, R = Cy b). Compound 1a could be converted into the dimethyl species [Re(MeCN)(NO)(PiPr3)2Me2] (3a) applying MeLi in toluene; the related methylation of 1b, however, failed. Abstraction of a Br– ion from 1a,b with [Na][BAr′4] in acetontrile yields the air‐stable salts [Re(MeCN)2(NO)(PR3)2Br]+[BAr′4]– (4a,b) (R = iPr a, R = Cy b) and under 1 bar of H2 complexes 1a,b were converted into the known dihydrogen species [Re(η2‐H2)(NO)(PR3)2(Br)2] (5a,b) (R = iPr a, R = Cy b). Reduction of [Re(MeCN)(NO)(PR3)2Br2] (1a,b) with Na/Hg under 1 bar of C2H4 afforded the butadiene complex [Re(η4‐C4H6)(η2‐H2C=CH2)(NO)(PR3)2] (6a,b) (R = iPr a, R = Cy b) via oxidative coupling of two coordinated ethylene groups followed by double β‐H shift and subsequent reductive H2 elimination from the formed dihydride complex. Reduction of the complexes [Re(CO)(NO)(PR3)2Cl2] (7a,b) (R = iPr a, R = Cy b) with Na/Hg yields the pentacoordinate species [Re(CO)(NO)(PR3)2(η2‐H2C=CH2)] (8a,b) (R = iPr a, R = Cy b) under the same conditions as for 6a,b. Reaction of 8a with 1 equiv. of B(C6F5)3 leads to the [Re(CO)2{NOB(C6F5)3}(PiPr3)2] compound (9a) and to the carbonyl nitrosyl complexes [Re(CO)2(NO)(PiPr3)2] (10a) with evolution of ethylene. The same reaction of 8a and 8b, but applying 1 bar of CO, leads to exclusive formation of 9a,b. Complexes 4a, 4b, 6b, 8a, 9a, and 9b were characterized by X‐ray diffraction studies.(© Wiley‐VCH Verlag GmbH & Co. KGaA, 69451 Weinheim, Germany, 2007)
Decomposition Cascades of Dicoordinate Copper(I) Chalcogenides
Authors: Jacobsen Heiko , Fink Mark J. 
Published: October 2007

AbstractCu–E, Si–E, and Cu–P bond energies of R3PCuESiR3 and CuESiR3 complexes (E = O, S, Se) have been investigated using PBE density‐functional calculations, and including empirical corrections for dispersive interactions (DFT‐D). The bond energies have been used to investigate likely pathways of molecular decomposition. The energy profile for thermal decomposition is to a large degree independent of the nature of the phosphane ligands and silyl groups. Oxides, sulfides, and selenides have qualitatively the same thermal decomposition profile. Thermal decomposition is not likely to produce copper chalcogenide units CuE, but elemental copper Cu instead. Consideration of intermolecular van der Waals attraction suggests that the linear geometry of system tBu3PCuOSiPh3 as found in the crystal is most likely due to crystal packing and intermolecular forces.(© Wiley‐VCH Verlag GmbH & Co. KGaA, 69451 Weinheim, Germany, 2007)
Specific Recognition of Disaccharides in Water by an Artificial Bicyclic Carbohydrate Receptor (Eur. J. Org. Chem. 30/2007)
Authors: Reenberg Theis , Nyberg Nils , Duus Jens Ø. , van Dongen Joost L. J. , Meldal Morten 
Published: October 2007

AbstractThe cover picture shows the artificial molecular recognition of cellobiose in an aqueous environment. The complex depicted forms from an organo‐peptidic receptor composed of a bicyclic peptide containing a naphthalene bridge and the disaccharide cellobiose. The complex was analyzed by 2D NMR spectroscopy, and the changes in the chemical shift observed upon receptor titration (shown for 1‐H of the naphthalene ring) with cellobiose is in agreement with the structure of the complex. The largest shifts were observed for those receptor protons in immediate contact with the saccharide. The formation of the complex measured by ESI‐MS at increasing collision energies is shown in the stacked plot inset and can be performed as a high throughput screening (HTS) of carbohydrate–receptor interaction. Details are discussed in the article by M. Meldal et al. on p. 5003 ff.
Electromigration of a heteroconjugated imidazole–acetate complex in ACN
Authors: Porras Simo P. , Jussila Matti 
Published: September 2007

AbstractACN is an extremely poor hydrogen bond donor and therefore the anions dissolved in it are solvated mainly by other hydrogen bond donors (e.g. uncharged acids) possibly present in the solution. Under properly selected experimental conditions stabilization via hydrogen bonding can be used for separation in CE as has been demonstrated for uncharged acids by several authors. Electromigration based on heteroconjugation can be of importance, e.g. when aqueous separation medium cannot be used due to stability reasons. It also allows CE to be used as a tool for solution chemistry measurements, if the required physicochemical properties of the studied system are known or they can be predicted with sufficient accuracy by existing theories. In the present work we showed that also an uncharged base can stabilize an anion via hydrogen bonding in ACN. In the setup imidazole was chosen as a model base and acetate ion as complexing anion in equimolar acetic acid‐acetate buffer. The resulted hydrogen‐bonded imidazole–acetate complex (i.e. heteroconjugate) possesses a charge and can thus migrate in CE. It was shown that the studied complexation in ACN is sensitive to competition by other hydrogen bond donors such as water and methanol. On the other hand, acetone, which is a poor hydrogen bond donor, did not have much effect on the complexation. To take the effect of ionic strength on mobility into account, mobilities of the imidazole–acetate complex measured at various ionic strengths were corrected to zero ionic strength by the aid of conductivity equation. A fit of the 1:1 binding isotherm to the ionic strength corrected mobility versus acetate concentration data led to rather good correlation. However, x‐reciprocal linear transformation of the binding isotherm showed nonlinearity, which could be partly explained by homoconjugation of acetic acid and acetate ion. Since the homoconjugation constant for acetic acid under present experimental conditions was not available, theoretical simulations were used to demonstrate the effects of homoconjugation. The possibility of multiple complexation of imidazole was discussed as well.
Seismic analysis of two‐way asymmetric building systems under bi‐directional seismic ground motions
Authors: Lin Jui‐Liang , Tsai Keh‐Chyuan 
Published: September 2007

AbstractAn approximation approach of seismic analysis of two‐way asymmetric building systems under bi‐directional seismic ground motions is proposed. The procedures of uncoupled modal response history analysis (UMRHA) are extended to two‐way asymmetric buildings simultaneously excited by two horizontal components of ground motion. Constructing the relationships of two‐way base shears versus two‐way roof translations and base torque versus roof rotation in ADRS format for a two‐way asymmetric building, each modal pushover curve bifurcates into three curves in an inelastic state. A three‐degree‐of‐freedom (3DOF) modal stick is developed to simulate the modal pushover curve with the stated bifurcating characteristic. It requires the calculation of the synthetic earthquake and angle β. It is confirmed that the 3DOF modal stick is consistent with single‐degree‐of‐freedom modal stick in an elastic state. A two‐way asymmetric three‐story building was analyzed by UMRHA procedure incorporating the proposed 3DOF modal sticks. The analytical results are compared with those obtained from nonlinear response history analysis. It is shown that the 3DOF modal sticks are more rational and effective in dealing with the assessment of two‐way asymmetric building systems under two‐directional seismic ground motions. Copyright © 2007 John Wiley & Sons, Ltd.
Spectral filtering as a method of visualising and removing striped artefacts in digital elevation data
Authors: Arrell Katherine , Wise Steve , Wood Jo , Donoghue Danny 
Published: September 2007

AbstractSpectral filtering was compared with traditional mean spatial filters to assess their ability to identify and remove striped artefacts in digital elevation data. The techniques were applied to two datasets: a 100 m contour derived digital elevation model (DEM) of southern Norway and a 2 m LiDAR DSM of the Lake District, UK. Both datasets contained diagonal data artefacts that were found to propagate into subsequent terrain analysis. Spectral filtering used fast Fourier transformation (FFT) frequency data to identify these data artefacts in both datasets. These were removed from the data by applying a cut filter, prior to the inverse transform. Spectral filtering showed considerable advantages over mean spatial filters, when both the absolute and spatial distribution of elevation changes made were examined. Elevation changes from the spectral filtering were restricted to frequencies removed by the cut filter, were small in magnitude and consequently avoided any global smoothing. Spectral filtering was found to avoid the smoothing of kernel based data editing, and provided a more informative measure of data artefacts present in the FFT frequency domain. Artefacts were found to be heterogeneous through the surfaces, a result of their strong correlations with spatially autocorrelated variables: landcover and landsurface geometry. Spectral filtering performed better on the 100 m DEM, where signal and artefact were clearly distinguishable in the frequency data. Spectrally filtered digital elevation datasets were found to provide a superior and more precise representation of the landsurface and be a more appropriate dataset for any subsequent geomorphological applications. Copyright © 2007 John Wiley & Sons, Ltd.
Sub‐micromolar increase in [Ca2+]i triggers delayed exocytosis of ATP in cultured astrocytes
Authors: Pryazhnikov Evgeny , Khiroug Leonard 
Published: October 2007

AbstractAstrocytes release a variety of transmitter molecules, which mediate communication between glial cells in the brain and modulate synaptic transmission. ATP is a major glia‐derived transmitter, but the mechanisms and kinetics of ATP release from astrocytes remain largely unknown. Here, we combined epifluorescence and total internal reflection fluorescence microscopy to monitor individual quinacrine‐loaded ATP‐containing vesicles undergoing exocytosis in cultured astrocytes. In resting cells, vesicles exhibited three‐dimensional motility, spontaneous docking and release at low rate. Extracellular ATP application induced a Ca2+‐dependent increase in the rate of exocytosis, which persisted for several minutes. Using UV flash photolysis of caged Ca2+, the threshold [Ca2+]i for ATP exocytosis was found to be ∼350 nM. Subthreshold [Ca2+]i transients predominantly induced vesicle docking at plasma membrane without subsequent release. ATP exocytosis triggered either by purinergic stimulation or by Ca2+ uncaging occurred after a substantial delay ranging from tens to hundreds of seconds, with only ∼4% of release occurring during the first 30 s. The time course of the cargo release from vesicles had two peaks centered on ≤10 s and 60 s. These results demonstrate that: (1) [Ca2+]i elevations in cultured astrocytes trigger docking and release of ATP‐containing vesicles; (2) vesicle docking and release have different Ca2+ thresholds; (3) ATP exocytosis is delayed by several minutes and highly asynchronous; (4) two populations of ATP‐containing vesicles with distinct (fast and slow) time course of cargo release exist in cultured astrocytes. © 2007 Wiley‐Liss, Inc.
Factors associated with antidepressant use in depressed and non‐depressed community‐dwelling elderly: the three‐city study
Authors: Soudry Agnès , Dufouil Carole , Ritchie Karen , Dartigues Jean‐François , Tzourio Christophe , Alpérovitch Annick 
Published: October 2007

AbstractObjectivesThe aim of this study was to identify factors associated with antidepressant use in non‐depressed and depressed elderly persons, assuming that they varied according to clinical status.MethodsWe studied 7,868 French community‐dwelling subjects aged 65 years and over. The Center for Epidemiological Studies‐Depression scale and the Mini International Neuropsychiatric Interview were used to define three groups: non‐depressed, high depressive symptoms and current major depressive disorder. Separate analyses were performed to identify the factors which were associated with antidepressant use in each group.ResultsAntidepressant use (55% selective serotonin re‐uptake inhibitors, 25% tricyclic antidepressants, 20% other types) increased from 4.9% in non‐depressed subjects to 17.3% in subjects with high depressive symptoms (HDS) and 33.6% of in those with current major depressive disorder (MDD). The factors associated with antidepressant use varied according to depression status. In particular, men with current MDD were more often treated with antidepressants than women whereas, in both the HDS and the non‐depressed groups, antidepressant use was, as has been observed elsewhere, more frequent in women. Gender also had a strong modifying effect on the relationship between antidepressant use and history of major depression. Finally, the direction of the association between antidepressant use and cognitive performance varied according to depression status.ConclusionsThis study showed that the direction and strength of the association between antidepressant use and demographic and health‐related factors varied according to the severity of depression symptoms. Further studies are needed to clarify the relationship between gender and cognition and antidepressant use. Copyright © 2007 John Wiley & Sons, Ltd.
Patterns and predictors of medication compliance, diversion, and misuse in adult prescribed methylphenidate users
Authors: Darredeau Christine , Barrett Sean P. , Jardin Bianca , Pihl Robert O. 
Published: October 2007

AbstractObjectivesTo examine patterns and predictors of medication compliance, diversion, and misuse in a sample of adults with prescriptions for the stimulant medication methylphenidate (MPH).MethodsSixty‐six adults currently prescribed MPH (53% male) completed structured interviews and provided details regarding their medication and other substance use histories.ResultsOn average, participants reported using their medication as prescribed on 14.5 (SD 11.7) of the past 30 days; 44% admitted to diverting it and 29% admitted to inappropriate use. While analyses revealed that medication misuse, diversion, and level of compliance were interrelated and all associated with concurrent illicit substance use, each also had other distinct associations. Specifically, MPH misuse was associated with the use of illicit stimulants such as amphetamine and cocaine, diversion with age and age of MPH prescription, and compliance with participation in an attention deficit hyperactivity disorder (ADHD) support group. Regression analyses revealed that misuse and poor compliance were both best predicted by concurrent illicit substance use, while the model that best predicted diversion included age of first MPH prescription (younger) and MPH misuse.ConclusionsPoor medication compliance, diversion, and misuse are relatively common and interrelated among adult MPH users. MPH prescriptions should be monitored closely in individuals with histories of illicit substance use. Copyright © 2007 John Wiley & Sons, Ltd.
A spatial analysis of hydro‐climatic and vegetation condition trends in the Yellow River basin
Authors: Tang Qiuhong , Oki Taikan , Kanae Shinjiro , Hu Heping 
Published: October 2007

AbstractStream‐gauge data indicate that the flow of the Yellow River has declined during the past several decades. Zero flow in sections of the river channel, i.e. the Yellow River drying‐up phenomenon, has occurred since the 1970s. In this paper we present an analysis of changes in the spatial patterns of climatic and vegetation condition data in the Yellow River basin based on data from meteorological stations and satellites. The climatic data are from 1960 to 2000 and the vegetation condition data are from 1982 to 2000. The angular‐distance‐weighted interpolation method is used to get climatic data coverage from station observations. The spatial distribution of tendency is detected with Student's t‐test. The spatial patterns of climatic and vegetation condition change was analysed together with the statistical data on human activities. The analysis indicates that the precipitation decreases and temperature increases in most parts of the Yellow River basin, the evaporative demand of the atmosphere decreases in the upper reaches and increases in the lower reaches, and human activities have improved the vegetation condition in the irrigation districts. The Loess Plateau, the Tibetan Plateau, and the irrigation districts are respectively suggested as precipitation, temperature, and human activity hot spots of the Yellow River drying‐up phenomenon. Copyright © 2007 John Wiley & Sons, Ltd.
Application of multivariate analysis to suspended matter particle size distribution in a karst aquifer
Authors: Fournier M. , Massei N. , Mahler B. J. , Bakalowicz M. , Dupont J. P. 
Published: October 2007

AbstractNumerous quantitative and qualitative variables control suspended sediment dynamics in karst systems. The objective of this study was to identify the hydrodynamic variables controlling the transport properties of particles in a karst aquifer (western Paris basin). The particle size distribution of suspended sediment infiltrating via a swallow hole was compared to that in discharge from a spring, allowing identification of the particle transport properties of the karst system. Hill and Smith analysis, a type of multivariate analysis that allows joint examination of quantitative and qualitative variables, was used to identify the hydrodynamic parameters controlling the transport properties of the suspended matter. The results demonstrate that the particle size distribution discharging at the karst spring is controlled by spring discharge and the hydraulic gradient of the system. The hydraulic gradient is defined by the piezometric level and the stage of the Seine River, which is in turn controlled by the tide. This study illustrates the use of Hill and Smith analysis to identify those variables which control suspended sediment transport. It also illustrates the application of this analysis to identify boundary conditions and evaluate variables which control the behaviour of the hydrologic system. Copyright © 2007 John Wiley & Sons, Ltd.
Control of silicon species released from poly(lactic acid)‐polysiloxane hybrid membranes
Authors: Maeda Hirotaka , Kasuga Toshihiro 
Published: September 2007

AbstractNovel hybrid membranes consisting of poly(L‐lactic acid) (PLLA), aminopropyltriethoxysilane (APTES), and calcium carbonates were prepared for bioresorbable guided bone regeneration. A molecular chain of PLLA was bonded at the end of an organic chain in APTES through the amide bond formed between carboxy‐groups in PLLA and amino‐groups in ATPES. As a result, the hybrid membrane was formed. The PLLA in the membrane was an amorphous phase. By heating the membrane at 100°C for 1 h, the PLLA in the membrane crystallized and some organic chains in APTES and amide bonds decomposed. Moreover, numerous pores of 0.5–1 μm in diameter were newly formed at the surface. When the membranes before and after heat treatment were soaked in simulated body fluid, the amount of silicon species in SBF released from the membrane after heat treatment was higher than that before heat treatment. A test of osteoblast‐like cellular proliferation on the membrane showed that the membrane after heat treatment has much higher cell‐proliferation ability than that before heat treatment. © 2007 Wiley Periodicals, Inc. J Biomed Mater Res, 2008
Impact of pore size on the vascularization and osseointegration of ceramic bone substitutes in vivo
Authors: Klenke Frank M. , Liu Yuelian , Yuan Huipin , Hunziker Ernst B. , Siebenrock Klaus A. , Hofstetter Willy 
Published: September 2007

AbstractThe repair of bone defects with biomaterials depends on a sufficient vascularization of the implantation site. We analyzed the effect of pore size on the vascularization and osseointegration of biphasic calcium phosphate particles, which were implanted into critical‐sized cranial defects in Balb/c mice. Dense particles and particles with pore sizes in the ranges 40–70, 70–140, 140–210, and 210–280 μm were tested (n = 6 animals per group). Angiogenesis, vascularization, and leukocyte–endothelium interactions were monitored for 28 days by intravital microscopy. The formation of new bone and the bone–interface contact (BIC) were determined histomorphometrically. Twenty‐eight days after implantation, the functional capillary density was significantly higher with ceramic particles whose pore sizes exceeded 140 μm [140–210 μm: 6.6 (±0.8) mm/mm2; 210–280 μm: 7.3 (±0.6) mm/mm2] than with those whose pore sizes were lesser than 140 μm [40–70 μm: 5.3 (±0.4) mm/mm2; 70–140 μm: 5.6 (±0.3) mm/mm2] or with dense particles [5.7 (±0.8) mm/mm2]. The volume of newly‐formed bone deposited within the implants increased as the pore size increased [40–70 μm: 0.07 (±0.02) mm3; 70–140 μm: 0.10 (±0.06) mm3; 140–210 μm: 0.13 (±0.05) mm3; 210–280 μm: 0.15 (±0.06) mm3]. Similar results were observed for the BIC. The data demonstrates pore size to be a critical parameter governing the dynamic processes of vascularization and osseointegration of bone substitutes. © 2007 Wiley Periodicals, Inc. J Biomed Mater Res, 2008