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16 results on '"Wells, B. R."'

2. Apparatus for ejection of an instrument cover

Author

Rowland, C. W and Wells, B. R

Subjects
Machine Elements And Processes
Abstract

Apparatus for ejecting covers of instrument packages using differential pressure principle

Published
1969

3. Cleavage of bovine skin type III collagen by proteolytic enzymes. Relative resistance of the fibrillar form.

Author

Birkedal-Hansen, H, Taylor, R E, Bhown, A S, Katz, J, Lin, H Y, and Wells, B R

Abstract

We have studied the susceptibility of fibrils formed from fetal bovine skin type III collagen to proteolytic enzymes known to cleave within the helical portion of the molecule (vertebrate and microbial collagenase, polymorphonuclear elastase, trypsin, thermolysin) and to two general proteases of broad specificity (plasmin, Pronase). Fibrils reconstituted from neutral salt solutions, at 35 degrees C, were highly resistant to nonspecific proteolysis by general proteases such as polymorphonuclear elastase, trypsin, and thermolysin but were rapidly dissolved by bacterial and vertebrate collagenases at rates of 12-45 mol X mol-1 X h-1. In solution, type III collagen was readily cleaved by each of the proteases (with the exception of plasmin), as well as by the true collagenases, although at different rates. Turnover numbers determined by viscometry at 35 degrees C were: human collagenase, approximately equal to 1500 h-1; microbial (clostridial) collagenase, approximately equal to 100 h-1; and general proteases, 23-52 h-1. In addition it was shown that pronase cleaves type III collagen in solution at 22 degrees C by attacking the same Arg-Gly bond in the alpha 1(III) chain as trypsin. However, like other proteases, Pronase was rather ineffective against fibrillar forms of type III collagen. It was also shown that transition of type III collagen as well as type I collagen to the fibrillar form resulted in a significant gain of triple helical thermostability as evidenced by a 6.8 degrees C increase in denaturation temperature (Tm = 40.2 degrees C in solution; Tm = 47.0 degrees C in fibrils).

Published
1985
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4. Degradation of type I collagen by rat mucosal keratinocytes. Evidence for secretion of a specific epithelial collagenase.

Author

Lin, H Y, Wells, B R, Taylor, R E, and Birkedal-Hansen, H

Abstract

Feeder-cell-independent serially propagating keratinocytes from rat oral mucosa (tongue) dissolved reconstituted type I [3H]collagen fibrils, although rather slowly. Analysis of the conditioned medium from such cultures revealed secretion of a Mr = 65,000 collagenase which remained almost entirely latent in the absence of exogenous protease activity. Addition of trypsin (0.1-1.0 microgram/ml) or plasmin (1.0-4.0 micrograms/ml) resulted in substantial acceleration of the collagenolytic process in stimulated secretion of latent collagenase and, at higher concentrations, in conversion of the latent enzyme to the catalytic form. The keratinocyte collagenase was indistinguishable from interstitial, fibroblast-type collagenases by several criteria including: cleavage of native type I collagen in solution at the characteristic collagenase-sensitive locus at 22 degrees C and dissolution of reconstituted type I collagen fibrils at 35 degrees C; activation by trypsin and by organomercurials and inhibition by Zn2+ and Ca2+ chelators; and cross-reaction with antibody to fibroblast-type procollagenase. Expression of collagenolytic activity in keratinocyte cultures was effectively regulated by cell density. The activity (on a per cell basis) was maximal at 10-20% confluence and was more than 95% “contact-inhibited” at subconfluent and early confluent densities (2-4 × 10(5)/cm2). Our findings show that mucosal keratinocytes possess a potent enzymatic apparatus for degradation of interstitial collagen fibrils which includes a classical vertebrate collagenase.

Published
1987
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5. Upland Habitat Development with Dredged Material: Engineering and Plant Propagation.

Author

ARMY ENGINEER WATERWAYS EXPERIMENT STATION VICKSBURG MS, Hunt,L Jean, Landin,Mary C, Ford,Alfred W, Wells,B R, ARMY ENGINEER WATERWAYS EXPERIMENT STATION VICKSBURG MS, Hunt,L Jean, Landin,Mary C, Ford,Alfred W, and Wells,B R

Abstract

Upland habitat development using dredged material as a substrate was shown by the Dredged Material Research Program (DMRP) to be a feasible alternative to standard dredged material disposal operations. This report synthesizes pertinent literature and research at three major DMRP upland field sites: Miller Sands in the Columbia River, Oregon; Bolivar Peninsula in Galveston Bay, Texas; and Nott Island in the Connecticut River, Connecticut. Guidelines for developing existing or potential dredged material disposal sites into upland habitat are presented: (a) planning and designing the project in relation to the proposed site and project goals; (b) construction of the site including dredging and disposal operations, substrate modifications, and vegetation establishment; (c) maintenance and management of the site as a habitat; (d) costs of proposed and sample projects; and (e) potential problems that may be encountered., Report on Dredged Material Research Program.

Published
1978

7. Rice production handbook

Author

Chaney, Henry M.; Moldenhauer, K. A. Kuenzel (Karen Ann Kuenzel), 1952-; Wells, B. R. (Bobby Ray), 1934-; Helms, Ronnie S. (Ronald Sloan), 1955-; Baldwin, Ford L.; Smith, Roy Jefferson, 1929-; Miley, W. N. (Woody N.); Norman, R. J. (Richard James), 1953-; Langston, John M.; Tacker, Philmon L.; Ferguson, James Arthur, 1939-; McDaniel, M. C. (Extension plant pathologist); Lee, Fleet N.; Johnson, Donald R. (Donald Ray), 1946-; Bernhardt, John L.; Gardisser, Dennis R.; Dilday, R. H. (Robert Henry); Benz, Raymond; Bivings, Bert; Guy, Charles Brandon; Huitink, Gary and Chaney, Henry M.; Moldenhauer, K. A. Kuenzel (Karen Ann Kuenzel), 1952-; Wells, B. R. (Bobby Ray), 1934-; Helms, Ronnie S. (Ronald Sloan), 1955-; Baldwin, Ford L.; Smith, Roy Jefferson, 1929-; Miley, W. N. (Woody N.); Norman, R. J. (Richard James), 1953-; Langston, John M.; Tacker, Philmon L.; Ferguson, James Arthur, 1939-; McDaniel, M. C. (Extension plant pathologist); Lee, Fleet N.; Johnson, Donald R. (Donald Ray), 1946-; Bernhardt, John L.; Gardisser, Dennis R.; Dilday, R. H. (Robert Henry); Benz, Raymond; Bivings, Bert; Guy, Charles Brandon; Huitink, Gary

8. Rice production handbook

Author

Chaney, Henry M.; Moldenhauer, K. A. Kuenzel (Karen Ann Kuenzel), 1952-; Wells, B. R. (Bobby Ray), 1934-; Huey, Bobby A.; Helms, Ronnie S. (Ronald Sloan), 1955-; Baldwin, Ford L.; Smith, Roy Jefferson, 1929-; Nastasi, Paolo; Miley, W. N. (Woody N.); Norman, R. J. (Richard James), 1953-; Langston, John M.; Tacker, Philmon L.; Ferguson, James Arthur, 1939-; McDaniel, M. C. (Extension plant pathologist); Lee, Fleet N.; Johnson, Donald R. (Donald Ray), 1946-; Bernhardt, John L.; Pierce, Robert A. (Extension wildlife specialist); Gardisser, Dennis R.; Dilday, R. H. (Robert Henry); Benz, Raymond and Chaney, Henry M.; Moldenhauer, K. A. Kuenzel (Karen Ann Kuenzel), 1952-; Wells, B. R. (Bobby Ray), 1934-; Huey, Bobby A.; Helms, Ronnie S. (Ronald Sloan), 1955-; Baldwin, Ford L.; Smith, Roy Jefferson, 1929-; Nastasi, Paolo; Miley, W. N. (Woody N.); Norman, R. J. (Richard James), 1953-; Langston, John M.; Tacker, Philmon L.; Ferguson, James Arthur, 1939-; McDaniel, M. C. (Extension plant pathologist); Lee, Fleet N.; Johnson, Donald R. (Donald Ray), 1946-; Bernhardt, John L.; Pierce, Robert A. (Extension wildlife specialist); Gardisser, Dennis R.; Dilday, R. H. (Robert Henry); Benz, Raymond

9. Phosphorus fertilization of rice on the Grand Prairie of Arkansas

Author

Place, G. A. (Gerald Alan); Wells, B. R. (Bobby Ray), 1934-;Sims, John L.; Hall, Vernon L. (Vernon Lloyd), Arkansas Agricultural Experiment Station, Place, G. A. (Gerald Alan); Wells, B. R. (Bobby Ray), 1934-;Sims, John L.; Hall, Vernon L. (Vernon Lloyd), and Arkansas Agricultural Experiment Station

10. High input wheat management

Author

Bacon, Robert K.; Wells, B. R. (Bobby Ray), 1934, Arkansas Agricultural Experiment Station, Bacon, Robert K.; Wells, B. R. (Bobby Ray), 1934, and Arkansas Agricultural Experiment Station

11. Influence of uneven emergence of rice on grain yield, yield components and milling quality

Author

Ntamatungiro, Sixte; Helms, Ronnie S. (Ronald Sloan), 1955-; Wells, B. R. (Bobby Ray), 1934-; Norman, R. J. (Richard James), 1953, Arkansas Agricultural Experiment Station, Ntamatungiro, Sixte; Helms, Ronnie S. (Ronald Sloan), 1955-; Wells, B. R. (Bobby Ray), 1934-; Norman, R. J. (Richard James), 1953, and Arkansas Agricultural Experiment Station

12. Nitrogen uptake of differentially emerged rice plants

Author

Ntamatungiro, Sixte; Helms, Ronnie S. (Ronald Sloan), 1955-; Wells, B. R. (Bobby Ray), 1934-; Norman, R. J. (Richard James), 1953, Arkansas Agricultural Experiment Station, Ntamatungiro, Sixte; Helms, Ronnie S. (Ronald Sloan), 1955-; Wells, B. R. (Bobby Ray), 1934-; Norman, R. J. (Richard James), 1953, and Arkansas Agricultural Experiment Station

13. Evaluation of dicyandiamide-amended urea on rice

Author

Helms, Ronnie S. (Ronald Sloan), 1955-; Norman, R. J. (Richard James), 1953-; Wells, B. R. (Bobby Ray), 1934, Arkansas Agricultural Experiment Station, Helms, Ronnie S. (Ronald Sloan), 1955-; Norman, R. J. (Richard James), 1953-; Wells, B. R. (Bobby Ray), 1934, and Arkansas Agricultural Experiment Station

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