bluuebunny/crossref_metadata_2025_split huggingface dataset:
Multinuclear Silver Ethynide Supramolecular Synthons for the Construction of Coordination Networks
Authors: Mak Thomas C. W. , Zhao Liang 
Published: February 2007

AbstractThe invariant appearance of the μ8 coordination mode for the C42− dianion in its silver(I) complexes, with four silver(I) atoms attached to each terminal ethynide moiety, implies that the Ag4⊂CCCC⊃Ag4 species may be considered as a new type of supramolecular synthon for the construction of 1D, 2D, and 3D coordination polymers. This Focus Review covers recent results on the synthesis and structural characterization of silver(I) arylethynide and alkylethynide complexes, which established the existence and utility of analogous polynuclear supramolecular synthons RCC⊃Agn (R=aryl or alkyl; n=4, 5) and Agn⊂C2RC2⊃Agn (R=p‐, m‐, o‐C6H4; n=4, 5). The interplay of silver–ethynide bonding, which can be classified into σ, π, and mixed (σ,π) types, with argentophilicity, π–π stacking, and other weak interactions highlights the complexity and challenge in building coordination networks of silver ethynide complexes.
Crosslinking of casein by microbial transglutaminase and its resulting influence on the stability of micelle structure
Authors: Partschefeld Claudia , Schwarzenbolz Uwe , Richter Sven , Henle Thomas 
Published: February 2007

AbstractThe influence of enzymatic crosslinking by microbial transglutaminase (mTG) on the stability of casein micelles of ultrahigh temperature (UHT)‐treated milk in the presence of EDTA (0–0.45 mM) or ethanol (0–74 vol%) as well as under high hydrostatic pressures up to 400 MPa was investigated. Disintegration of micelles and changes in micelle size were monitored by the measurement of turbidity as well as by dynamic light scattering. The results show that the incubation of UHTtreated milk with mTG resulted in an improved micelle stability toward disintegration on addition of EDTA, ethanol, or pressure treatment. Intramicellar formed isopetides significantly enhanced the stability of casein micelles. It is supposed that net‐like crosslinks are formed within the external region of the micelles and they adopt the stabilizing role of colloidal calcium phosphate within the micelles, thus making the micelles less contestable for disrupting influences.
Enhancement of cell growth in tissue‐engineering constructs under direct perfusion: Modeling and simulation
Authors: Chung C.A. , Chen C.W. , Chen C.P. , Tseng C.S. 
Published: February 2007

AbstractPerfusion bioreactors improve mass transfer in cell‐scaffold constructs. We developed a mathematical model to simulate nutrient flow through cellular constructs. Interactions among cell proliferation, nutrient consumption, and culture medium circulation were investigated. The model incorporated modified Contois cell‐growth kinetics that includes effects of nutrient saturation and limited cell growth. Nutrient uptake was depicted through the Michaelis–Menton kinetics. To describe the culture medium convection, the fluid flow outside the cell‐scaffold construct was described by the Navier–Stokes equations, while the fluid dynamics within the construct was modeled by Brinkman's equation for porous media flow. Effects of the media perfusion were examined by including time‐dependant porosity and permeability changes due to cell growth. The overall cell volume was considered to consist of cells and extracellular matrices (ECM) as a whole without treating ECM separately. Numerical simulations show when cells were cultured subjected to direct perfusion, they penetrated to a greater extent into the scaffold and resulted in a more uniform spatial distribution. The cell amount was increased by perfusion and ultimately approached an asymptotic value as the perfusion rates increased in terms of the dimensionless Peclet number that accounts for the ratio of nutrient perfusion to diffusion. In addition to enhancing the nutrient delivery, perfusion simultaneously imposes flow‐mediated shear stress to the engineered cells. Shear stresses were found to increase with cell growth as the scaffold void space was occupied by the cell and ECM volumes. The macro average stresses increased from 0.2 mPa to 1 mPa at a perfusion rate of 20 µm/s with the overall cell volume fraction growing from 0.4 to 0.7, which made the overall permeability value decrease from 1.35 × 10−2cm2 to 5.51 × 10−4cm2. Relating the simulation results with perfusion experiments in literature, the average shear stresses were below the critical value that would induce the chondrocyte necrosis. Biotechnol. Bioeng. 2007; 97: 1603–1616. © 2007 Wiley Periodicals, Inc.
Quantitative image analysis as a diagnostic tool for monitoring structural changes of anaerobic granular sludge during detergent shock loads
Authors: Costa J.C. , Abreu A.A. , Ferreira E.C. , Alves M.M. 
Published: February 2007

AbstractTwo shock loads of a commercial detergent (I—150 mg chemical oxygen demand (COD)/L, fed for 56 h; II—300 mg COD/L fed for 222 h) were applied in a lab‐scale Expanded Granular Sludge Blanket (EGSB) reactor, fed with 1,500 mg COD/L of ethanol. The impact of the surfactant was assessed in terms of granular sludge morphology, specific methanogenic activity (SMA) in the presence of individual substrates, and reactor performance. COD removal efficiency remained unaffected in the shock I, but 80 h after starting exposure to the shock II, the COD removal efficiency decreased drastically from 75 to 17%. In the first 8 h of operation of shock I, the SMA was stimulated and decreased afterwards, being recovered 5 days after the end of exposure time. Concerning to shock II, the SMA was immediately and persistently reduced during the exposure time, although, the inhibition of SMA in presence of H2/CO2 showed a trend to increase after the exposure time. Acetoclastic bacteria were observed as the most sensitive to the toxic effects of surfactant whereas the hydrogenotrophic bacteria were less affected. The inhibitory effects were dependent on surfactant concentration and exposure time. The ratio filaments length per total aggregates area (LfA) was an early‐warning indicator of biomass washout, since it increased 3 and 5 days before effluent volatile suspended solids (VSS) rise, respectively, in shocks I and II. Biotechnol. Bioeng. 2007; 98: 60–68. © 2007 Wiley Periodicals, Inc.
Crossed renal ectopia with fusion: Report of two patients
Authors: Boyan Neslihan , Kubat Huseyin , Uzum Ayse 
Published: February 2007

AbstractCrossed renal ectopia is one of the rarest urinary system anomalies. It is more often seen at autopsy than in clinical practice. Most cases of renal ectopia remain asymptomatic during life and are diagnosed incidentally. Renal ultrasonography, intravenous pyelography, computerized tomography, and renal scintigraphy (technetium‐based tests) are the imaging methods used for diagnosis. Demonstration of crossed renal ectopia is important because it is a predisposing factor for obstruction, infection, and neoplasia of the urinary system. We report two male patients who had unremarkable clinical findings. Both had left‐to‐right inferior crossed renal ectopia with fusion. Additionally, the first patient had a history of surgery for a recurrent inguinal hernia, whereas the second had crossed fused renal ectopia associated with nephroptosis. Surgeons should be aware of ectopic and fused kidneys to minimize perioperative complications because of the uncertain anatomy. Clin. Anat. 20:699–702, 2007. © 2007 Wiley‐Liss, Inc.
Relationship between the Zuckerkandl's tubercle and entrance point of the inferior laryngeal nerve
Authors: Bülent Yalçlın , Ozan Hasan 
Published: February 2007

AbstractThe Zuckerkandl's tubercle (ZT) is a lateral or posterior projection from the lateral thyroid lobe. It has been used as an anatomical landmark for location of the inferior laryngeal nerve (ILN). Because most nerve injuries occurred just below that point where the ILN passed under the inferior constrictor muscle, we aimed to investigate the relationship between the ZT and entrance point (EP) of the ILN. Forty‐five specimens taken from 26 male and 19 female cadavers were dissected. We found Grade 2 and Grade 3 ZTs in 58 sides (64% of 90 sides). The ZT was situated at the middle third of lateral lobe of the thyroid gland in 48 sides (82.7% of 58 sides). This group had three subgroups: (I) the ZTs indicated EPs of the ILN or the anterior laryngeal branch, (II) the ZTs covered the EPs of the ILN or the laryngeal branches or only the anterior laryngeal branch, and (III) the ZTs were below or above the EPs of the laryngeal branches. In conclusion, the ZTs pointed the EPs of the ILN or the laryngeal branches in 32 of 58 sides (55.2%). For this reason, we imagine that the ZT may be used as a landmark by surgeon to locate the EPs of the ILN or the laryngeal branches. Clin. Anat. 20:640–643, 2007. © 2007 Wiley‐Liss, Inc.
Isolated deep peroneal (fibular) nerve palsy in association with primary total hip arthroplasty
Authors: Ahmad I. , Patil S. 
Published: February 2007

AbstractWe present two patients sufffering isolated deep peroneal (fibular) nerve (DPN) palsies post primary total hip arthroplastry. The consistent factor in both patients was difficulty with initial dislocation and subsequent relocation. Both developed immediate isolated DPN palsies, with loss of dorsiflexion and paraesthesia over the first web space. The superficial peroneal nerve was intact in both. Depsite intensive physiotherapy neither patient regained a return to pre‐morbid motor or sensory function. Common peroneal nerve (CPN) palsy is common than due to a number of important anatomical factors. It is thought that the deep and superficial branches of this nerve also exist as discrete fascicles and these same factors make the deep division more frequently affected. Recovery is prolonged and incomplete despite intensive physiotherapy, thus putting emphasis on prevention. Clin. Anat. 20:703–704, 2007. © 2007 Wiley‐Liss, Inc.
A Two‐Photon Fluorescent Probe for Lipid Raft Imaging: C‐Laurdan
Authors: Kim Hwan Myung , Choo Hyo‐Jung , Jung Soon‐Young , Ko Young‐Gyu , Park Won‐Hwa , Jeon Seung‐Joon , Kim Chul Hoon , Joo Taiha , Cho Bong Rae 
Published: February 2007

AbstractThe lipid‐rafts hypothesis proposes that naturally occurring lipid aggregates exist in the plane of membrane that are involved in signal transduction, protein sorting, and membrane transport. To understand their roles in cell biology, a direct visualization of such domains in living cells is essential. For this purpose, 6‐dodecanoyl‐2‐(dimethylamino)naphthalene (laurdan), a membrane probe that is sensitive to the polarity of the membrane, has often been used. We have synthesized and characterized 6‐dodecanoyl‐2‐[N‐methyl‐N‐(carboxymethyl)amino]naphthalene (C‐laurdan), which has the advantages of greater sensitivity to the membrane polarity, a brighter two‐photon fluorescence image, and reflecting the cell environment more accurately than laurdan. Lipid rafts can be visualized by two‐photon microscopy by using C‐laurdan as a probe. Our results show that the lipid rafts cover 38 % of the cell surface.
Synthesis, Structures, and Stability of N‐Donor‐Stabilized N‐Silylphosphoranimine Cations
Authors: Huynh Keith , Rivard Eric , Lough Alan J. , Manners Ian 
Published: February 2007

AbstractA series of DMAP‐stabilized (DMAP=4‐dimethylaminopyridine) N‐silylphosphoranimine cations [DMAP⋅PR2NSiMe3]+, bearing R=Cl ([8]+), Me ([10 a]+), Me/Ph ([10 b]+), Ph ([10 c]+), and OCH2CF3 ([10 d]+) substituents, have been synthesized from the reactions of the parent phosphoranimines Cl3PNSiMe3 (3) and XR2PNSiMe3 (X=Cl (9), Br (11); R=Me (9 a and 11 a), Me/Ph (9 b and 11 b), Ph (9 c and 11 c), and OCH2CF3 (9 d and 11 d)) with DMAP and silver salts as halide abstractors. Reactions in the absence of silver salts yield the corresponding cations, with halide counterions. The stability of the salts is highly dependent on the phosphoranimine substituent and the nature of the counteranion, such that electron‐withdrawing substituents and non‐coordinating anions yield the most stable salts. X‐ray structural determination of the cations reveal extremely short phosphoranimine PN bond lengths for the cations [8]+ and [10 d]+ (1.47–1.49 Å) in which electron‐withdrawing substituents are present and a longer phosphoranimine PN length for the cation [10 a]+ (1.53 Å) in which electron‐donating substituents are present. Very wide bond angles at nitrogen are observed for the salts containing the cation [10 d]+ (158–166°) and indicate significant sp hybridization at the nitrogen centre.
Porphyrin‐Appended Europium(III) Bis(phthalocyaninato) Complexes: Synthesis, Characterization, and Photophysical Properties
Authors: Bian Yongzhong , Chen Xinghai , Wang Dongying , Choi Chi‐Fung , Zhou Yang , Zhu Peihua , Ng Dennis K. P. , Jiang Jianzhuang , Weng Yuxiang , Li Xiyou 
Published: February 2007

AbstractMixed cyclization of 3‐mono‐, 4‐mono‐, or 4,5‐di(porphyrinated) phthalonitrile compounds2,3, or6and unsubstituted phthalonitrile with the half‐sandwich complex [EuIII(acac)(Pc)] (Pc=phthalocyaninate, acac=acetylacetonate) as the template in the presence of 1,8‐diazabicyclo[5.4.0]undec‐7‐ene (DBU) inn‐pentanol afforded novel porphyrin‐appended europium(III) bis(phthalocyaninato) complexes7–9in 30–40 % yield. These mixed tetrapyrrole triads and tetrad were spectroscopically and electrochemically characterized and their photophysical properties were also investigated with steady‐state and transient spectroscopic methods. It has been found that the fluorescence of the porphyrin moiety is quenched effectively by the double‐decker unit through an intramolecular photoinduced electron‐transfer process, which takes place in several hundred femtoseconds, while the recombination of the charge‐separated state occurs in several picoseconds. By using different phthalocyanines containing different numbers of porphyrin substituents at the peripheral or nonperipheral position(s) of the ligand, while the other unsubstituted phthalocyanine remains unchanged in these double‐deckers, the effects of the number and the position of the porphyrin substituents on these photophysical processes were also examined.
A new temperature‐sensitive contrast mechanism for MRI: Curie temperature transition‐based imaging
Authors: Settecase F. , Sussman M. S. , Roberts T. P. L. 
Published: February 2007

AbstractA temperature‐sensitive MRI contrast mechanism is proposed based on the physical property, the Curie temperature (Tc), at which a ferromagnetic material transitions to paramagnetic state and vice versa. To evaluate the feasibility of this new contrast mechanism, experiments were performed with solid gadolinium metal, which has a Tc of 20°C. In phantom and ex vivo experiments, the magnetic susceptibility artifact area decreased with increasing temperature transitioning across Tc (p < 0.05). Similar results would be expected for a variety of ferromagnetic substances with substance‐specific Tc values. Temperature‐sensitive MRI contrast agents harnessing this mechanism may be used to (1) indicate regional attainment of specific temperatures in thermotherapy, (2) render an accumulated contrast agent more or less visible by the external application of appropriate heating or cooling, or (3) quantify tissue temperature based on MR image characteristics and magnetic susceptibility artifact caused by a ferromagnetic–paramagnetic transitioning substance. Copyright © 2007 John Wiley & Sons, Ltd.
ASOM applied to column stability
Authors: Ranjbaran A. , Hashemi S. 
Published: February 2007

AbstractA new method for computation of buckling load and mode shape of a non‐uniform column is proposed. Based on the principles of calculus of variations the stability analysis of the column is defined as an optimization problem. Different known techniques of optimization are candidates for solution process. Through analysis of typical columns and comparison of the results with those of other methods, the basic theory and implementation of the presented method is verified. Copyright © 2007 John Wiley & Sons, Ltd.
Isoform‐specific interaction of Flamingo/Starry Night with excess Bazooka affects planar cell polarity in the Drosophila wing
Authors: Wasserscheid Isabel , Thomas Ulrich , Knust Elisabeth 
Published: February 2007

AbstractEpithelia display two types of polarity, apical–basal and planar cell polarity (PCP), and both are crucial for morphogenesis and organogenesis. PCP signaling pathways comprise transmembrane proteins, such as Flamingo/Starry Night, and cytoplasmic, membrane‐associated proteins such as Dishevelled. During establishment of PCP in the Drosophila wing, PCP proteins accumulate apically in distinct “cortical domains” on proximal and distal plasma membranes. This finding suggests that their localized function depends on prior definition of apicobasal polarity. Here, we show that overexpression of Bazooka, a PDZ‐domain protein essential for apicobasal polarity in the embryo, perturbs development of PCP, but has no effect on apicobasal polarity. The PCP phenotype is associated with a failure to restrict Flamingo/Starry night to the proximal and distal plasma membranes of the wing epithelium. We further demonstrate that flamingo expresses two differentially spliced RNAs in wing imaginal discs, which encode two isoforms of the atypical cadherin Flamingo. The predominant Starry night–type form contains a PDZ‐binding motif, which mediates binding to Bazooka in vitro. Pull‐down assays support the occurrence of such an interaction in wing imaginal discs. The results suggest that interaction between the apicobasal and planar cell polarity systems has to be tightly coordinated to ensure proper morphogenesis of the wing disc epithelium. Developmental Dynamics 236:1064–1071, 2007. © 2007 Wiley‐Liss, Inc.
Reactions of Group 13 Organometallics tBu3M with Distibanes Sb2R4 (Eur. J. Inorg. Chem. 7/2007)
Authors: Schuchmann Daniella , Kuczkowski Andreas , Fahrenholz Sonja , Schulz Stephan , Flörke Ulrich 
Published: February 2007

AbstractThe cover picture shows the photograph of Robert Bunsen and the statue of Jöns Jakob Berzelius in the centre of Berzeli Park (Stockholm). Both famous chemists investigated the chemistry of tetramethyldiarsane As2Me4 (kakodyl), one of the first organometallic compounds that were initially prepared by Claude‐Louis Cadet de Gassicourt (Cadet's fuming liquid) in 1757. Distibanes Sb2R4, the heavier congeners of diarsanes, exhibit much weaker metal–metal bonds and can be used for interesting bond‐making and bond‐breaking reactions with group 13 organometallic compounds. Details are discussed in the article by S. Schulz et al. on p. 931 ff. The artwork was designed by Dr. Edgar Luttmann.
Cover Picture: Polyazaacenes – On the Way to Stable, Fluorescent and Redox‐Active Derivatives (Eur. J. Org. Chem. 8/2007)
Authors: Stöckner Frances , Beckert Rainer , Gleich Dieter , Birckner Eckhard , Günther Wolfgang , Görls Helmar , Vaughan Gavin 
Published: February 2007

AbstractThe cover picture shows the dyotropic rearrangement of 1,4,5,8‐tetraazafulvalenes into pyrazino‐[2,3‐b]pyrazines. In the case of Ar = 4‐tert‐butylphenyl, the products were immediately transformed, in the presence of oxygen, into derivatives of octaazahexacene through a cascade reaction. These highly ring‐fused compounds display a strong red fluorescence in solution and, in addition, can easily be reduced reversibly. In contact with air, the yellow fluorescent leuco compound formed quickly reoxidized, which is visible by red fluorescent streaks. Details are discussed in the article by R. Beckert et al. on p. 1237 ff.
Computer‐assisted identification of multitrace electrophoretic patterns in differential display experiments
Authors: Vähämaa Heidi , Ojala Pekka , Pahikkala Tapio , Nevalainen Olli S. , Lahesmaa Riitta , Aittokallio Tero 
Published: February 2007

AbstractModern multicapillary devices allow researchers to address increasingly complex biological questions involving comparisons of gene expression patterns across electrophoretic samples under various experimental conditions. As labor‐intensive visual evaluation of the electrophoretic results is often the bottleneck of large‐scale differential display (DD) studies, one way to further streamline this process is to focus only on a highly compressed list of the most potential patterns that are likely to provide reliable findings. To enable the identification of such candidate patterns, we present a computer‐assisted method for objective ranking of multitrace peak patterns in DD experiments. The fundamental component of the multitrace pattern ranking method (MRANK) is the multiple alignment algorithm that allows for discovery of patterns involving sets of peak complexes from various electrophoretic samples. A score value is attached to each detected pattern which characterizes how accurately the pattern resembles the desired pattern query, freely defined by the researcher. The ranked pattern list produced by MRANK is validated against visual evaluation in terms of detecting and ranking a group of relevant patterns in a DD analysis of T‐helper cell differentiation. We demonstrate high enrichment of the desired patterns on top of the score‐ranked list (e.g., 90% of the visually selected patterns are discovered by looking through the first 3% of patterns in the ranked list of all patterns). The results suggest that a substantial amount of manual labor can be saved without compromising the accuracy of the findings by prioritizing the patterns according to MRANK output in the visual confirmation phase.
Enantioseparation by CE with vancomycin as chiral selector: Improving the separation performance by dynamic coating of the capillary with poly(dimethylacrylamide)
Authors: Wang Zhaoyan , Wang Junfeng , Hu Zhide , Kang Jingwu 
Published: February 2007

AbstractAn approach for improving the separation performance of the enantioseparation by CE with vancomycin as chiral selector is described. In the present method, a solution of poly(dimethylacrylamide) (PDMA) was used for dynamic coating of the capillary wall to minimize the adsorption of vancomycin onto the capillary wall, and to depress the EOF. Compared with the bare fused‐silica capillaries and the capillaries coated with the polycationic polymer hexadimethrine bromide (HDB), the PDMA‐coated capillary displayed the best separation performance. The resulting coating could withstand hundreds of runs without losing its function. Moreover, a partial filling technique was applied to avoid interference in detection caused by the presence of vancomycin in the buffer. The separation time was shortened when a short‐end‐injection technique was applied. Several parameters such as buffer pH, vancomycin concentration and plug length of the vancomycin solution for the separation were optimized. Under the optimal conditions, all tested enantiomers, including FMOC amino acids derivatives, ketoprofen and fenoprofen, were baseline‐separated in less than 4.2 min.
Analysis of electrokinetic transport of a spherical particle in a microchannel
Authors: Unni Harikrishnan N. , Keh Huan J. , Yang Chun 
Published: February 2007

AbstractElectrokinetically driven microfluidic devices that are used for biological cell/particle manipulation (e.g., cell sorting, separation) involve electrokinetic transport of these particles in microchannels whose dimension is comparable with particles' size. This paper presents an analytical study on electrokinetic transport of a charged spherical particle in a charged parallel‐plate microchannel. Under the thin electric double‐layer assumption, solutions in closed‐form solutions for the particle velocity and disturbed electrical and fluid velocity fields are obtained for plane‐symmetric (along the channel centerline) and asymmetric (off the channel centerline) motions of a sphere in a parallel‐plate microchannel. The effects of relative particle size and eccentricity (i.e., off the centerline distance) on a particle's translational and rotational velocities are analyzed.