bluuebunny/crossref_metadata_2025_split huggingface dataset:
Aggregation of concentrated polymer latex in stirred vessels
Authors: Vaccaro Andrea , Šefčík Ján , Wu Hua , Morbidelli Massimo , Bobet Josselin , Fringant Christophe 
Published: May 2006

AbstractAn assessment of the relative magnitude of the timescales of mixing and aggregation of fully destabilized polymeric latices in stirred vessels is presented. It is demonstrated that, in industrially relevant conditions (that is, volume fractions above 10% and primary aggregate sizes below 200 nm), latices aggregate and possibly gel before complete mixing is achieved. By means of focused beam reflectance measurements, we measure on‐line and in situ the size of aggregates obtained aggregating a PVDC latex at salt concentrations above the critical coagulation concentration in a stirred vessel operated in semibatch. Several experimental runs are conducted and averages of the aggregate size distribution, that is, volume and number averages, are measured at various values of the feed flowrate, feed solid volume fraction, stirring speed and final volume fraction in the vessel. It is found that at high feeding volume fractions aggregates instantaneously aggregate and gel on entering the vessel. Resulting aggregates are then broken down to volume weighted average sizes falling in the range between 100 and 400 microns at steady state. The experimental results are interpreted in terms of a competition between the aggregation/gelation process and mixing. In particular, by evaluating the relevant characteristic times, it is found that the process is dominated by the competition between mesomixing at the location, where the latex enters the vessel and the aggregation/gelation process. Scanning electron micrographs of dry samples obtained after thermal treatment show aggregate morphologies which further support the above interpretation. © 2006 American Institute of Chemical Engineers AIChE J, 2006
Clinical and epidemiological findings in patients with central ray deficiency: Split hand foot malformation (SHFM) in Manitoba, Canada
Authors: Elliott Alison M. , Reed Martin H. , Chudley Albert E. , Chodirker Bernard N. , Evans Jane A. 
Published: May 2006

AbstractWe conducted a clinical population study to examine the incidence and epidemiology of split hand foot‐malformation (SHFM) in Manitoba from 1957 to 2003. The total number of births during this period was 850,742. Forty‐three patients with SHFM were identified, resulting in an incidence of 1 in 19,784 births. Most patients were ascertained through referrals to the Section of Genetics and Metabolism at the Children's Hospital, Winnipeg, Manitoba. Overall, 22 (51.2%) of affected individuals were females and 21 (48.8%) were male. The left upper limb (LUL) was the most frequently affected, (in 46.5% of patients). The right hand was involved in 39.5%. In 4 patients (9.3%) all four limbs were affected. SHFM is classified as a failure of formation of parts according to the International Federation of Surgical Societies of the Hand (IFSSH) and has also been categorized as Typical or Atypical. Individuals in the Manitoba cohort were classified into two main categories: Typical (29 cases) and Atypical (3 cases). However, 11 patients were not easily placed into either group and comprised a distinct category termed “difficult to classify.” Patients in the three groups were then further subdivided depending on whether or not they had additional congenital anomalies. These complex patients included those with single gene disorders in which SHFM has been reported (e.g., ectodermal dysplasia Ectrodactyly Clefting (EEC), tibial aplasia with SHFM, fibular aplasia with SHFM), as well as those with other recognized or unknown patterns of anomalies. Two had deletions involving 9q and 5p respectively. Unlike some other studies, we did not find an excess of males or right‐sided defects and only two of the cases—two sisters—were related. © 2006 Wiley‐Liss, Inc.
Evaluating therapeutic targets for reperfusion‐related brain hemorrhage
Authors: Maier Carolina M. , Hsieh Lily , Crandall Trisha , Narasimhan Purnima , Chan Pak H. 
Published: May 2006

AbstractObjectiveEarly reperfusion after an ischemic stroke can cause blood–brain barrier injury with subsequent cerebral edema and devastating brain hemorrhage. These complications of early reperfusion, which result from excess production of reactive oxygen species, significantly limit the benefits of stroke therapies. In this article, we use a novel animal model that facilitates identification of specific components of the reperfusion injury process, including vascular injury and secondary brain damage, and allows assessment of therapeutic interventions.MethodsKnock‐out (KO) mice containing 50% manganese‐superoxide dismutase activity (SOD2‐KO) and transgenic mice overexpressing SOD2 undergo transient focal ischemia and reperfusion followed by assessment of infarct, edema, hemorrhage rates, metalloproteinase activation, and microvascular injury.ResultsSOD2‐KO mice demonstrate delayed (>24h) blood–brain barrier breakdown associated with activation of matrix metalloproteinases, inflammation, and high brain hemorrhage rates. These adverse consequences are absent in wild‐type littermates and minocycline‐treated SOD2‐KO animals. Increased hemorrhage rates also are absent in SOD2 overexpressors, which have reduced vascular endothelial cell death. Finally, we show that the tight junction membrane protein, occludin, is an early and specific target in oxidative stress‐induced microvascular injury.InterpretationThis model is ideal for studying ischemia/reperfusion‐induced vascular injury and secondary brain hemorrhage and offers a unique opportunity to evaluate antioxidant‐based neurovascular protective strategies as potential adjunct treatments to currently approved stroke therapies such as thrombolysis and endovascular clot retrieval.Ann Neurol 2006
The Preparation and Characterisation of Hetero‐ and Homobimetallic Complexes Containing Bridging Naphthalene‐1,8‐dithiolato Ligands
Authors: Aucott Stephen M. , Duerden Daniel , Li Yang , Slawin Alexandra M. Z. , Woollins J. Derek 
Published: May 2006

AbstractHomo‐ and heterobimetallic complexes of the form [(PPh3)2(μ2‐1,8‐S2‐nap){MLn}] (in which (1,8‐S2‐nap)=naphtho‐1,8‐dithiolate and {MLn}={PtCl2} (1), {PtClMe} (2), {PtClPh} (3), {PtMe2} (4), {PtIMe3} (5) and {Mo(CO)4} (6)) were obtained by the addition of [PtCl2(NCPh)2], [PtClMe(cod)] (cod=1,5‐cyclooctadiene), [PtClPh(cod)], [PtMe2(cod)], [{PtIMe3}4] and [Mo(CO)4(nbd)] (nbd=norbornadiene), respectively, to [Pt(PPh3)2(1,8‐S2‐nap)]. Synthesis of cationic complexes was achieved by the addition of one or two equivalents of a halide abstractor, Ag[BF4] or Ag[ClO4], to [{Pt(μ‐Cl)(μ‐η2:η1‐C3H5)}4], [{Pd(μ‐Cl)(η3‐C3H5)}2], [{IrCl(μ‐Cl)(η5‐C5Me5)}2] (in which C5Me5=Cp*=1,2,3,4,5‐pentamethylcyclopentadienyl), [{RhCl(μ‐Cl)(η5‐C5Me5)}2], [PtCl2(PMe2Ph)2] and [{Rh(μ‐Cl)(cod)}2] to give the appropriate coordinatively unsaturated species that, upon treatment with [(PPh3)2Pt(1,8‐S2‐nap)], gave complexes of the form [(PPh3)2(μ2‐1,8‐S2‐nap){MLn}][X] (in which {MLn}[X]={Pt(η3‐C3H5)}[ClO4] (7), {Pd(η3‐C3H5)}[ClO4] (8), {IrCl(η5‐C5Me5)}[ClO4] (9), {RhCl(η5‐C5Me5)}[BF4] (10), {Pt(PMe2Ph)2}[ClO4]2 (11), {Rh(cod)}[ClO4] (12); the carbonyl complex {Rh(CO)2}[ClO4] (13) was formed by bubbling gaseous CO through a solution of 12. In all cases the naphtho‐1,8‐dithiolate ligand acts as a bridge between two metal centres to give a four‐membered PtMS2 ring (M=transition metal). All compounds were characterised spectroscopically. The X‐ray structures of 5, 6, 7, 8, 10 and 12 reveal a binuclear PtMS2 core with Pt⋅⋅⋅M distances ranging from 2.9630(8)–3.438(1) Å for 8 and 5, respectively. The napS2 mean plane is tilted with respect to the PtP2S2 coordination plane, with dihedral angles in the range 49.7–76.1° and the degree of tilting being related to the Pt⋅⋅⋅M distance and the coordination number of M. The sum of the Pt(1)coordination plane/napS2 angle, a, and the Pt(1)coordination plane/M(2)coordination plane angle, b, a+b, is close to 120° in nearly all cases. This suggests that electronic effects play a significant role in these binuclear systems.
Density Functional Study of Methyl Chemisorption on Polycyclic Aromatic Hydrocarbons
Authors: Unterreiner Barbara V. , Carissan Yannick , Klopper Wim 
Published: May 2006

AbstractThe reactions of methyl radicals with large (up to C96H24) polycyclic aromatic hydrocarbons (PAHs) are studied by density functional calculations to shed light on the experimentally observed deposition of carbon on highly oriented pyrolytic graphite (HOPG), which occurs when hot HOPG (decorated by nanometre‐sized defects) is exposed to methyl radicals. The equilibrium structures of the reaction products, together with transition structures for PAHs up to the size of phenanthroperylene, are determined using the density functionals B3LYP, TPSSh, BP86 and TPSS. The structures are analysed by computing the π orbital axis vector (POAV) and the altitude of the reactive carbon above the molecular plane of the PAH. The strongest CCH3 bonds are found at the edges of the PAHs, where the s character of the C orbital involved in the bond is roughly 25 % (sp3 hybrid orbital). Carbon atoms inside the PAH form bonds with the methyl radical through atomic orbitals with about 16 % s character in the POAV analysis. These bonds are much weaker than those at the edges of the PAH, while the reactive carbon has moved about 40 pm above the molecular plane. At the edges, the PAH carbon atoms do not leave the molecular plane to this extent. The computed barrier heights and geometrical parameters of the transition structures are in agreement with Hammond’s postulate, and the relative energies of all of the equilibrium structures can be rationalized by Hückel molecular orbital (HMO) theory.
A Theoretical Study on Structures, Bonding Energies and Aromaticity of Two New Series of Dinuclear Phosphametallocenes: (η5‐P5)MM′(η5‐P5) and (η5‐C5H5)MM′(η5‐P5) (M, M′ = Zn, Cd)
Authors: Liu Zi‐Zhong , Tian Wei Quan , Feng Ji‐Kang , Zhang Gang , Li Wei‐Qi , Cui Yan‐Hong , Sun Chia‐Chung 
Published: May 2006

AbstractThe equilibrium geometries, the energies, the harmonic vibrational frequencies, and the nucleus independent chemical shifts (NICSs) of the ground state of (η5‐P5)MM′(η5‐P5) and (η5‐C5H5)MM′(η5‐P5) (M, M′ = Zn, Cd) are calculated by the hybrid density functional method B3LYP with LANL2DZ basis sets. The analysis of energy and harmonic frequencies on the equilibrium geometries of both series dinuclear deca‐ and pentaphosphametallocenes shows that all the minima with singlet electronic state have an staggered (9 ° ≤D(E–M–M–E′) ≤ 36°) conformation except for the eclipsed CpCd2(P5) (C5v), and all the D5h and the D5d symmetric conformations are transition states while the energy differences between the most stable minimum and the transition states are very small (≤ 0.1 kcal/mol), thus, the rotation of the P5 ring about M–M bond in all complexes is almost free. The analysis of the NBO, the Laplacian of the electron density, the electrostatic interaction energy, the bonding energy decomposition, and the molecular orbital correlation diagrams for the two series complexes reveals that the properties of all the dinuclear phosphametallocenes investigated are similar to that of the dizinc metallocenes. The M–M (or M–M′) bond in the dinuclear phosphametallocenes is a weak σ covalent bond, and the magnitude of bonding energy of the M–M (or M–M′) bond correlates with the energy difference between the energy of HOMO in M(η5‐P5) (or MCp) (2A, C5v) fragment and the energy of HOMO‐2 in [MM′(η5‐P5)2] (1A, D5, or D5h) [or (η5‐P5)MM′Cp (1A, C5, or C5v)] (M, M′ = Zn, Cd). The strength of the M–M (or M–M′) bond plays a decisive role on the stability of the dinuclear phosphametallocenes. However, the M–(η5‐P5) (or M–Cp) bonding mainly is ionic. Among the different dinuclear phosphametallocenes with the same ligands, the bonding energies of the M–M (or M–M′) bond and of the M–(η5‐P5) (or M–Cp) bond decrease as M varying from Zn to Cd. Among the different phosphametallocenes with the same metals, the bonding energies of the M–M (or M–M′) bond and the M–ligand bond increase with ligand varying from the (η5‐P5) to the Cp. The negative NICSs indicate that all dinuclear phosphametallocenes have aromaticity. The various dissected bond NICS contributions reveal that the NICS contributions of the metal–ligand bond, the metal–metal bond, and the metal lone pair electrons to the overall aromaticity in the Zn‐containing dinuclear phosphametallocenes are different from their counterpart contributions in the Cd‐containing dinuclear phosphametallocenes, such difference causes that the overall NICSs of the Zn‐containing dinuclear phosphametallocenes are more negative than that of the Cd‐containing dinuclear phosphametallocenes. (© Wiley‐VCH Verlag GmbH & Co. KGaA, 69451 Weinheim, Germany, 2006)
A Mild Stereo‐ and Enantiospecific Conversion of 2,3‐Diaryl‐Substituted Oxiranes into 2,2‐Dimethyl‐1,3‐Dioxolanes by an Acetone/Amberlyst 15 System
Authors: Solladié‐Cavallo Arlette , Choucair Elias , Balaz Milan , Lupattelli Paolo , Bonini Carlo , Di Blasio Nadia 
Published: May 2006

AbstractAmberlyst 15 is an efficient catalyst for the reaction of aryl‐substituted oxiranes with acetone to prepare 2,2‐dimethyl‐1,3‐dioxolanes in high yields. trans‐2,3‐Diaryloxiranes afford trans‐acetonides enantiospecifically at room temperature, and the use of enantiopure 2,3‐diaryloxiranes results in no loss of stereochemical integrity in the resulting trans‐acetonides. (© Wiley‐VCH Verlag GmbH & Co. KGaA, 69451 Weinheim, Germany, 2006)
One‐Pot Three‐Component Synthesis of 3‐Halofurans and 3‐Chloro‐4‐iodofurans
Authors: Karpov Alexei S. , Merkul Eugen , Oeser Thomas , Müller Thomas J. J. 
Published: May 2006

AbstractA novel sequence of Sonogashira coupling and acid‐mediated nucleophilic addition to the ynone intermediate with concomitant deprotection and cyclocondensation opens a new one‐pot synthetic access to 3‐chloro‐, 3‐iodo‐, and 3‐chloro‐4‐iodo‐furans in moderate to good yields. (© Wiley‐VCH Verlag GmbH & Co. KGaA, 69451 Weinheim, Germany, 2006)
Partitioning resistance to overland flow on rough mobile beds
Authors: Hu Shixiong , Abrahams Athol D. 
Published: May 2006

AbstractFor overland flows transporting predominantly bed load over rough mobile beds without rainfall, resistance to flow f may be divided into four components: surface resistance fs, form resistance ff, wave resistance fw, and bed‐mobility resistance fm. In this study it is assumed that f = fs + ff + fw + fm, and an equation is developed for each component. The equations for fs and ff are borrowed from the literature, while those for fw and fm are developed from two series of flume experiments in which the beds are covered with various concentrations of large‐scale roughness elements. The first series consists of 65 experiments on fixed beds, while the second series contains 194 experiments on mobile beds. All experiments were performed on the same slope (S = 0·114) and with the same size of sediment (D = 0·00074 m). The equations for fw and fm are derived by a combination of dimensional analysis and regression analysis. The analyses reveal that the major controls of fw and fm are the Froude number F and the concentration of the roughness elements Cr. When the equations for fw and fm are summed, the Cr terms cancel out, leaving fw+m = 0·63F−2. An equation is developed that predicts total f, and the contributions of fs, ff, fw and fm to f are computed from the series 1 and 2 experiments. An analysis of the first series reveals that in clear‐water flows over fixed beds, fw accounts for 52 per cent of f. A similar analysis of the second series indicates that in sediment‐laden flows over mobile beds fw comprises 37 per cent and fm 32 per cent of f, so that together fw and fm account for almost 70 per cent of f. Finally, regression analyses indicate that where F > 0·5, fw and fm each vary with F−2 and fw/fm = 1·18. The equation developed here for predicting total f applies only to the range of hydraulic, sediment, and bed roughness conditions represented by the experimental data. With additional data from a broader range of conditions the same methodology as employed here could be used to develop a more general equation. Copyright © 2006 John Wiley & Sons, Ltd.
Transcription factor co‐expression patterns indicate heterogeneity of oligodendroglial subpopulations in adult spinal cord
Authors: Kitada Masaaki , Rowitch David H. 
Published: May 2006

AbstractOligodendrocytes and their precursors serve critical roles in the maintenance of neurological function. Although activity of the transcription factors (TFs) Olig1, Olig2, Sox10, and Nkx2.2 is required during early oligodendrocyte development, their later expression in adult central nervous system is rather poorly characterized. Here we have analyzed co‐expression patterns of these transcriptional proteins in the mouse cervical spinal cord. Our findings indicate that TF co‐expression patterns describe heterogeneity in adult oligodendroglial populations (1) in distinct sub‐regions of grey and white matter and (2) with respect to level of maturation from proliferating precursors to myelinating oligodendrocytes. Our findings suggest that TF co‐expression patterns identify and might regulate distinct functional classes of grey and white matter oligodendroglia. © 2006 Wiley‐Liss, Inc.
Extraction of Candida rugosa lipase from aqueous solutions into organic solvents by forming an ion‐paired complex with AOT
Authors: Wu Jin Chuan , Chua Pei Song , Chow Yvonne , Li Ruijiang , Carpenter Keith , Yu Hongwei 
Published: May 2006

AbstractCandida rugosa lipase was extracted from aqueous solutions into organic solvents by forming an ion‐paired complex with sodium bis(2‐ethylhexyl)sulfosuccinate (AOT). The optimal aqueous pH for lipase recovery was 4.5 and the optimal CaCl2 concentration was 10 mmol dm−3. The lipase recovery decreased with increasing aqueous enzyme concentration but increased with increasing AOT concentration in the organic phase. The presence of polar co‐solvents in the aqueous phase did not obviously improve the lipase recovery, which was also little influenced by the type of hydrophobic organic solvent used for solubilising AOT. Surprisingly, no detectable activity of the ion‐paired C. rugosa lipase was observed for both the esterification of lauric acid with 1‐propanol in isooctane and the hydrolysis of olive oil in isooctane containing an appropriate amount of water. The ion‐paired C. rugosa lipase mediated the enantioselective crystallisation of racemic ketoprofen in isooctane, indicating the feasibility of using it as a chiral mediator for the enantioseparation of hydrophobic racemic compounds in organic systems. Copyright © 2006 Society of Chemical Industry
Intraoperative sonographically guided resection of hemangioblastoma in the cerebellum
Authors: Wang Yi , Wang Yong , Gao Xiang , Wang Yida 
Published: May 2006

AbstractWe report a case of hemangioblastoma in a 37‐year‐old woman. Intraoperative sonography was used to significantly reduce the duration of the intervention and ensure thorough resection of the tumor. We recommend real‐time intraoperative sonography as a routine procedure in the surgical treatment of hemangioblastoma. © 2006 Wiley Periodicals, Inc. J Clin Ultrasound 34:247–249, 2006
Enlarged lymph nodes in porta hepatis: Sonographic sign of chronic hepatitis B and C infections
Authors: Kuo Hsing‐Tao , Lin Ching‐Yih , Chen Jyh‐Jou , Tsai Sun‐Lung 
Published: May 2006

AbstractPurpose.Enlarged lymph nodes in the hepatoduodenal ligament are prevalent in chronic infection with hepatitis B virus (HBV) or hepatitis C virus (HCV); however, the clinical significance of this sonographic finding in an endemic area is unknown.Methods.Six hundred outpatients were categorized into 4 groups (nonviral, HBV, HCV, and HBV and HCV) using viral markers. The prevalence and size of enlarged lymph nodes were compared. Correlation between clinical parameters and nodal size was evaluated.Results.The incidence of detectable nodes in both the HBV group and the HCV group was significantly increased (56.9% and 69.4%, respectively; both p < 0.001) compared with the nonviral group; this rate was independent of aminotransferase levels. Nodal width was the only significant parameter when viral and nonviral groups were compared (p < 0.05). If a width of more than 5 mm was used to predict HBV or HCV infection, the positive predictive rate was 88% and the specificity was 89%.Conclusions.Lymph nodes in the hepatoduodenal ligament, especially those wider than 5 mm, suggest chronic HBV or HCV infection instead of only chronic hepatitis, especially in an endemic area such as Taiwan. © 2006 Wiley Periodicals, Inc. J Clin Ultrasound 34:211–216, 2006
Doppler ultrasound assessment of posterior tibial artery size in humans
Authors: Sabatier Manning J. , Stoner Lee , Reifenberger Matt , McCully Kevin 
Published: May 2006

AbstractPurpose.The difference between structural remodeling and changes in tone of peripheral arteries in the lower extremities has not been evaluated. The purpose of this study was to (1) evaluate the day‐to‐day reproducibility and interobserver reliability (IOR) of posterior tibial artery (PTA) diameter measurements and (2) evaluate the effect of posture on PTA diameter at rest (Drest), during 10 minutes of proximal cuff occlusion (Dmin), and after the release of cuff occlusion (Dmax), as well as range (Dmax − Dmin) and constriction [(Dmax − Drest)/(Dmax − Dmin) × 100] in vivo.Methods.We used B‐mode sonography to image the PTA during each condition.Results.Day‐to‐day reliability was good for Drest (intraclass correlation coefficient [ICC] 0.95; mean difference 4.2%), Dmin (ICC 0.93; mean difference 5.4%), and Dmax (ICC 0.99; mean difference 2.2%). The coefficient of repeatability for IOR was 70.5 μm, with a mean interobserver error of 4.7 μm. The seated position decreased Drest (2.6 ± 0.2 to 2.4 ± 0.3 mm; p = 0.002), increased Dmin (2.1 ± 0.2 to 2.4 ± 0.2 mm; p = 0.001), and decreased Dmax (3.1 ± 0.4 to 2.8 ± 0.3 mm; p < 0.001) compared with the supine position. The seated position also decreased arterial range (Dmax − Dmin) from 0.9 ± 0.2 to 0.5 ± 0.1 mm (p = 0.003) and increased basal arterial constriction from 57 ± 19% to 105 ± 27% (p = 0.007).Conclusions.The system employed for measuring PTA diameter yields unbiased and consistent estimates. Furthermore, lower extremity arterial constriction and range change with posture in a manner consistent with known changes in autonomic activity. © 2006 Wiley Periodicals, Inc. J Clin Ultrasound 34:223–230, 2006
Heel pad thickness and athletic activity in healthy young adults: A sonographic study
Authors: Uzel Murat , Cetinus Ercan , Ekerbicer H. Cetin , Karaoguz Ahmet 
Published: May 2006

AbstractPurpose.The aim of this study was to investigate the sonographic changes of heel fat pad thickness and compressibility index in healthy young adults in relation to level of athletic activity.Materials and Methods.One hundred ten young adults (55 women and 55 men) with a body mass index between 18.5 and 24.9 were divided into 3 groups according to their athletic activity level: group 1, sedentary (n = 50); group 2, athletic activity <7 hours/week (n = 30); and group 3, athletic activity ≥7 hours/week (n = 30). The loaded heel pad thickness (LHPT) and unloaded heel pad thickness (ULHPT) were measured via sonography, and the heel pad compressibility index (HPCI) was calculated.Results.The mean values of ULHPT, LHPT, and HPCI in group 1 were similar to those of group 2 (p > 0.05) and group 3 (p > 0.05). The mean values of ULHPT, LHPT, and HPCI were similar in the left and right feet in the 3 groups (p > 0.05). There was no correlation between level of athletic activity and ULHPT, LHPT, or HPCI.Conclusions.The heel pad thickness and HPCI of individuals engaging in athletic activity up to an average of 11 hours/week were similar to those of sedentary individuals. © 2006 Wiley Periodicals, Inc. J Clin Ultrasound 34:231–236, 2006