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  • 1
    Electronic Resource
    Electronic Resource
    Effect of catalyst on the reactive processing of polyesters with epoxy-functional polymers (1993)
    Stamford, Conn. [u.a.] : Wiley-Blackwell
    Polymer Engineering and Science 33 (1993), S. 675-685 
    Details
    ISSN: 0032-3888
    Keywords: Chemistry ; Chemical Engineering
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology , Mechanical Engineering, Materials Science, Production Engineering, Mining and Metallurgy, Traffic Engineering, Precision Mechanics , Physics
    Notes: The objective this work was to determine the effects of selected polyester catalysts on the reaction of a polyester with epoxy functional polymers. Polyesters containing various catalyst metals were melt blended with either an ethylene-co-glycidyl methacrylate or a styrene-co-glycidyl methacrylate copolymer. The viscosities of the blends were monitored as a function of mixing time using torque rheometry. In addition, the molecular weight distributions of selected samples were analyzed using gel permeation chromatography. Both the torque rheometry and the gel permeation chromatography results indicate that the polyester reacts with epoxy functional polymers. This reaction occurs under conditions and at processing times which are readily obtainable in conventional melt processing equipment. Furthermore, the reaction kinetics of polyesters with glycidyl methacrylate copolymers are dramatically affected by the nature of the catalyst system used to prepare the polyester. Under the conditions used, antimony catalysts are particularly effective at promoting the reaction between polyesters and the epoxy functionality and the activity of the catalysts studied appears to decrease in the following order: antimony 〉 gallium 〉 tin ≃ titanium 〉 germanium. Manipulation of the polyester catalyst system may offer a method to control the extent of reaction obtained in reactive processing of polyesters with epoxy functional compounds.
    Additional Material: 16 Ill.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1002/pen.760331104
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  • 2
    Electronic Resource
    Electronic Resource
    Use of multiple monoclonal antibodies to characterize the major microtubule-associated protein in sea urchin eggs (1985)
    New York, NY : Wiley-Blackwell
    Cell Motility and the Cytoskeleton 5 (1985), S. 431-446 
    Details
    ISSN: 0886-1544
    Keywords: Life and Medical Sciences ; Cell & Developmental Biology
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Biology , Medicine
    Notes: Microtubules assembled from sea urchin eggs with the use of taxol contain a 77,000-dalton protein as the major nontubulin component [Vallee and Bloom (1983): Proc Natl. Acad. Sci. U.S.A. 80:6259-6263]. We have raised five monoclonal antibodies to this protein to aid in its characterization. Immunoblot analysis of the sea urchin microtubule purification fractions indicated that the protein copurified quantitatively with microtubules. All five antibodies stained the mitotic spindle of dividing sea urchin eggs by immunofluorescence microscopy, indicating that the protein was a component of the mitotic spindle and suggesting that it was actually localized on microtubules in vivo. Immunofluorescent staining of higher resolution was observed in a subpopulation of the coelomic cells found in adult sea urchins, confirming that the 77,000-dalton protein is indeed present on microtubules in vivo. Because taxol was not used for the immunofluorescence experiments, we conclude that the microtubule-associated protein (MAP)-like behavior of the 77,000-dalton protein in vitro was not induced artifactually by taxol. To determine whether this protein is a component of sea urchin microtubules in general, cilia obtained from blastula stage embryos and sperm tail flagella were analyzed with the antibodies. The protein was undetectable by both immunoblot analysis and immunofluorescence microscopy in both preparations of axonemal microtubules. These results indicated that the 77,000-dalton MAP is restricted to cytoplasmic and mitotic microtubules in the sea urchin. Furthermore, in view of its particular abundance in embryos, whose microtubules are devoted substantially to mitosis, the 77,000-dalton MAP is likely to play an important role in regulating the activity of mitotic spindle microtubules in the sea urchin.
    Additional Material: 8 Ill.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1002/cm.970050602
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  • 3
    Electronic Resource
    Electronic Resource
    Copurification of kinesin polypeptides with microtubule-stimulated Mg-ATPase activity and kinetic analysis of enzymatic properties (1989)
    New York, NY : Wiley-Blackwell
    Cell Motility and the Cytoskeleton 12 (1989), S. 195-215 
    Details
    ISSN: 0886-1544
    Keywords: mechanochemistry ; fast axonal transport ; cytoskeleton ; vesicle ; motor protein ; Life and Medical Sciences ; Cell & Developmental Biology
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Biology , Medicine
    Notes: Determination of kinetic properties for kinesin adenosine triphosphatase (ATPase), a proposed motor for transport of membranous organelles, requires adequate amounts of kinesin with a consistent level of enzymatic activity. A purification procedure is detailed that produces approximately 2 mg of kinesin at up to 96% purity from 800 g of bovine brain. This protocol consists of a microtubule affinity step using 5′-adenylylimidodiphosphate (AMP-PNP); followed by gel filtration, ion exchange, and hydroxylapatite chromatography; and then sucrose density gradient centrifugation. The microtubule-activated ATPase activity of kinesin coeluted with kinesin polypeptides throughout the purification. Highly purified kinesin had a Vmax of 0.31 μmol/min/mg in the presence of microtubules, with a Km for ATP of 0.20 mM. The kinetic constants obtained in these studies compare favorably with physiological levels of ATP and microtubules. Variations in buffer conditions for the assay were found to affect ATPase activity significantly. A study of the ability of kinesin to utilize a variety of cation-ATP complexes indicated that kinesin is a microtubule-stimulated Mg-ATPase, but kinesin is able to hydrolyze Ca-ATP, Mn-ATP, and Co-ATP as well as Mg-ATP in the presence of microtubules. In the absence of microtubules, Ca-ATP appears to be the best substrate. Studies with several inhibitors of ATPases determined that vanadate inhibited kinesin ATPase at the lowest concentrations of inhibitor, but significant inhibition of the ATPase also occurred with submillimolar concentrations of AMP-PNP. Other inhibitors of kinesin include N-ethylmaleimide, adenosine diphosphate (ADP), pyrophosphate, and tripolyphosphate. Further characterization of the kinetic properties of the kinesin ATPase is important for understanding the molecular mechanisms for transport of membranous organelles along microtubules.
    Additional Material: 10 Ill.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1002/cm.970120403
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  • 4
    Electronic Resource
    Electronic Resource
    Association of kinesin with characterized membrane-bounded organelles (1992)
    New York, NY : Wiley-Blackwell
    Cell Motility and the Cytoskeleton 23 (1992), S. 19-33 
    Details
    ISSN: 0886-1544
    Keywords: synaptic vesicle ; mitochondria ; coated vesicle ; immunogold electron microscopy ; motor protein ; Life and Medical Sciences ; Cell & Developmental Biology
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Biology , Medicine
    Notes: The family of molecular motors known as kinesin has been implicated in the translocation of membrane-bounded organelles along microtubules, but relatively little is known about the interaction of kinesin with organelles. In order to understand these interactions, we have examined the association of kinesin with a variety of organelles. Kinesin was detected in purified organelle fractions, including synaptic vesicles, mitochondria, and coated vesicles, using quantitative immunoblots and immunoelectron microscopy. In contrast, isolated Golgi membranes and nuclear fractions did not contain detectable levels of kinesin. These results demonstrate that the organelle binding capacity of kinesin is selective and specific. The ability to purify membrane-bounded organelles with associated kinesin indicates that at least a portion of the cellular kinesin has a relatively stable association with membrane-bounded organelles in the cell. In addition, immuno-electron microscopy of mitochondria revealed a patch-like pattern in the kinesin distribution, suggesting that the organization of the motor on the organelle membrane may play a role in regulating organelle motility. © 1992 Wiley-Liss, Inc.
    Additional Material: 10 Ill.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1002/cm.970230104
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  • 5
    Electronic Resource
    Electronic Resource
    Nucleotide specificity for the bidirectional transport of membrane-bounded organelles in isolated axoplasm (1990)
    New York, NY : Wiley-Blackwell
    Cell Motility and the Cytoskeleton 15 (1990), S. 210-219 
    Details
    ISSN: 0886-1544
    Keywords: organelle motors ; nucleoside triphosphates ; fast axonal transport ; video microscopy ; Life and Medical Sciences ; Cell & Developmental Biology
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Biology , Medicine
    Notes: Video microscopy of isolated axoplasm from the squid giant axon permits correlated quantitative analyses of membrane-bounded organelle transport both in the intact axoplasm and along individual microtubules. As a result, the effects of experimental manipulations on both anterograde and retrograde movements of membrane-bounded organelles can be evaluated under nearly physiological conditions. Since anterograde and retrograde fast axonal transport are similar but distinct cellular processes, a systematic biochemical analysis is important for a further understanding of the molecular mechanisms for each. In this series of experiments, we employed isolated axoplasm of the squid to define the nucleoside triphosphate specificity for bidirectional organelle motility in the axon. Perfusion of axoplasm with 2-20 mM ATP preserved optimal vesicle velocities in both the anterograde and retrograde directions. Organelle velocities decreased to 〈50% of optimal values when the axoplasm was perfused with 10-20 mM UTP, GTP, ITP, or CTP with simultaneous depletion of endogenous ATP with hexokinase. Under the same conditions, TTP and ATP-γ-S were unable to support significant levels of transport. None of the NTPs tested had a differential effect on anterograde vs. retrograde movement of vesicles. Surprisingly, several inconsistencies were revealed when a comparison was made between these results and nucleoside triphosphate specificities that have been reported for putative organelle motors by using in vitro assays. These data may be used in conjunction with data from well-defined in vitro assays to develop models for the molecular mechanisms of axonal transport.
    Additional Material: 3 Ill.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1002/cm.970150404
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  • 6
    Electronic Resource
    Electronic Resource
    Rationalization for the molecular weight distributions of Coal pyrolysis liquids (1990)
    Hoboken, NJ : Wiley-Blackwell
    AIChE Journal 36 (1990), S. 1189-1199 
    Details
    ISSN: 0001-1541
    Keywords: Chemistry ; Chemical Engineering
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology , Process Engineering, Biotechnology, Nutrition Technology
    Notes: A model for coal thermal depolymerization is described and used to predict molecular weight distributions (MWD) of primary coal pyrolysis liquids. The model assumes that rupture of kinetically similar bonds in the coal is the preferred pathway for release of oligomers which ultimately become tars or extractables. The analysis provides the liquids MWD as a probability function of finding different oligomers composed of whole integer numbers of monomers and it is in excellent qualitative agreement with measured MWDs of coal pyrolysis liquids. The predicted MWDs are of the form of the gamma distribution function (GDF), and its parameters are interpreted in terms of the postulated chemistry of coal thermal depolymerization. Consequently, successful empirical correlations of experimental data on coal pyrolysis liquids MWDs with the GDF are better understood. Thus a protocol is provided to predict MWDs of pyrolysis liquids from knowledge of coal molecular structure.
    Additional Material: 9 Ill.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1002/aic.690360808
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  • 7
    Electronic Resource
    Electronic Resource
    Mass transfer driving forces in packed and fluidized beds (1969)
    Hoboken, NJ : Wiley-Blackwell
    AIChE Journal 15 (1969), S. 47-50 
    Details
    ISSN: 0001-1541
    Keywords: Chemistry ; Chemical Engineering
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology , Process Engineering, Biotechnology, Nutrition Technology
    Notes: The evaporation of n-decane into air from the surface of Celite particles, has been used for the establishment of mass transfer factors for both packed and fluidized bed systems. For these calculations log mean partial pressure differences were used. Actual concentration profiles of the transferable component were also experimentally measured by monitoring, at different bed heights, the concentration of n-decane vapor present in air used as the carrier gas. This was made possible through the use of an extremely sensitive hydrocarbon analyzer. The resulting profiles were used to obtain, by graphical integration, the actual driving force prevailing for each run. A nearly one-to-one correspondence was found to exist between the actual driving force and the corresponding log-mean value for both packed and fluidized bed runs.
    Additional Material: 4 Ill.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1002/aic.690150114
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  • 8
    Electronic Resource
    Electronic Resource
    Heat transfer to horizontal tubes in the freedboard region of a gas fluidized bed (1982)
    Hoboken, NJ : Wiley-Blackwell
    AIChE Journal 28 (1982), S. 759-765 
    Details
    ISSN: 0001-1541
    Keywords: Chemistry ; Chemical Engineering
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology , Process Engineering, Biotechnology, Nutrition Technology
    Notes: Overall heat transfer coefficients were measured for an instrumented horizontal tube of diameter 25 mm in the feedboard region above fluidized beds of 102 μm, 470 μm and 890 μm sand in a 0.25 m × 0.43 m × 3.0 m tall pilot scale column. The superficial air velocity varied from near minimum fluidization to 1.7 m/s. The instrumented tube was placed at different positions in a 16-tube bundle. The measured heat transfer coefficients were bounded for tubes near the expanded bed surface by the immersed tube values, and for remote tubes by the values for particle-free air in crossflow. The results are correlated within ± 12% by a simple equation which incorporates these limits. The results are in good qualitative and quantitative agreement with previous experimental results.
    Additional Material: 12 Ill.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1002/aic.690280509
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  • 9
    Electronic Resource
    Electronic Resource
    A monoclonal antibody to the human epidermal growth factor receptor (1982)
    New York, N.Y. : Wiley-Blackwell
    Journal of Cellular Biochemistry 20 (1982), S. 149-161 
    Details
    ISSN: 0730-2312
    Keywords: monoclonal antibody ; A431 ; EGF receptor ; chromosomal location ; internalization ; Life and Medical Sciences ; Cell & Developmental Biology
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Biology , Chemistry and Pharmacology , Medicine
    Notes: A monoclonal antibody of the IgG class, EGFR1, has been isolated using cells of the epidermoid carcinoma line A431 as immunogen. The A431 antigen recognized by EGFR1 has an apparent molecular weight of approximately 175,000, is a cell-surface molecule which can be specifically cross-linked to EGF, exhibits an EGF-stimulated protein kinase activity, binds to EGFR1 in a number of human cell lines to a degree which parallels EGF binding, and shows EGF-dependent internalization in A431 cells and human fibroblasts. We therefore conclude that EGFR1 is directed against an antigenic site on the human EGF receptor. EGFR1 is not mitogenic for human fibroblasts and does not inhibit EGF binding under a variety of assay conditions. The characterization of EGFR1 has allowed the unambiguous assignment of the structural gene for the human EGF receptor to chromosome 7. Preliminary results suggest that a convenient method for isolating a range of anti-EGF receptor monoclonal antibodies can be developed, based on a hybridoma supernatant screening assay in which positive supernatants bind selectively to a human-mouse cell hybrid containing human chromosome 7.
    Additional Material: 4 Ill.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1002/jcb.240200207
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  • 10
    Electronic Resource
    Electronic Resource
    Changes in the vertical dimensions of the human male skull during the third and fourth decades of lifeThis research was supported in part by a grant from The Medical Research Foundation of Texas (1964)
    New York, NY [u.a.] : Wiley-Blackwell
    The @Anatomical Record 150 (1964), S. 209-213 
    Details
    ISSN: 0003-276X
    Keywords: Life and Medical Sciences ; Cell & Developmental Biology
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Medicine
    Notes: A cephalometric radiographic appraisal of vertical skull growth occurring during the interim of one year was made on 71 caucasoid males at the Baylor University College of Dentistry, Dallas, Texas. The subjects were from 22 to 34 years of age. The dimensions assessed were the total skull height, the anterior cranial height, total facial height, upper facial height. and lower facial height. A significant increase was shown to occur in all the dimensions over a period of one year except in the dimension of anterior cranial height. It was concluded that skull growth does occur in male adults after the age generally accepted as that of maturity.
    Additional Material: 1 Ill.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1002/ar.1091500211
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