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Surface-modified macroporous polymer monoliths that resist the adsorption of proteins have been prepared using both single- and two-step photografting of hydrophilic monomers. The adsorption of protein was measured using a fluorescence assay based on bovine serum albumin labeled with fluorescein. Acrylamide, 2-hydroxyethyl methacrylate, vinyl pyrrolidinone, and poly(ethylene glycol) methacrylate (PEGMA) monomers were grafted and evaluated for their ability to prevent protein adsorption. Photografted layers of PEGMA reduced protein adsorption to less than 2% relative to unmodified surfaces. The sequential two-step photografting process consisted in (i) the formation of covalently bound surface photoinitiator sites followed by (ii) surface-localized graft polymerization. Monomer concentration and irradiation time during photografting were found to be the most important parameters for optimization of the two-step process. For simultaneous single-step photografting, the solvent and the presence of photoinitiator were the key variables. Initiator-free single-step photografting was less efficient than the two-step technique, yet resulted in similar prevention of protein adsorption after grafting for an extended period of time. The utility of photografting as a simple, patternable modification technique was demonstrated by first creating a hydrophilic surface within the monolith that was subsequently patterned with a layer of reactive 2-vinyl-4,4-dimethylazlactone polymer chains followed by the immobilization of green fluorescent protein.
An entry from the Cambridge Structural Database, the world’s repository for small molecule crystal structures. The entry contains experimental data from a crystal diffraction study. The deposited dataset for this entry is freely available from the CCDC and typically includes 3D coordinates, cell parameters, space group, experimental conditions and quality measures.
The increasing incidence of multi-drug resistant pathogenic bacteria, alongside viral and fungal human pathogens, supports the argument that skills in microbiology and infectious disease diagnosis, treatment and prevention are of growing global importance to be held among primary care clinicians. In Canada, inevitable future astronomical health care costs largely due to an aging population, have forced eyes upon pharmacists as one of (if not) the primary clinical professions to accommodate the growing need to accommodate patient access to health care while maintaining lower health care costs. As such, the role of pharmacists in health care is expanding, punctuating the need to enhance and improve Pharmacy education. Accurate assessment of the current gaps in Pharmacy education in Canada provides a unique opportunity for a new Pharmacy School at the University of Waterloo to establish a non-traditional, outcomes-based model to curricular design. We are applying this iterative curriculum assessment and design process to the establishment of a Medical Microbiology program, deemed as a prominent gap in former Pharmacy educational training programs. A pilot study was carried out distributing a comprehensive survey to a local group of pharmacists practicing in a variety of settings including: hospital, clinic, community, independent, industry and government, to assess perceived gaps in Pharmacy microbiology and infectious disease education. Preliminary findings of the surveys indicate that practitioners feel under-qualified in some areas of microbiology. The results are discussed with respect to a curricular redesign model and next steps in the process of curricular design are proposed.
A solute‐vacancy interaction model (SVIM) is proposed to account for the effects of minor alloying elements (e.g., Mo) on the breakdown of passive films. This model, which is an extension of the point‐defect model (15–17) that was previously developed to account for the growth and breakdown of passive films, assumes that highly charged solutes (e.g., Mo6+) form complexes with negatively charged cation vacancies . This interaction has the effect of reducing the flux of cation vacancies from the film/solution interface to the metal/film interface, and hence of increasing the breakdown voltage and the induction time for pitting attack. By using experimental data for 18%Cr‐1%Mo to calculate values for various parameters, we found that the SVIM accurately predicts the changes in and for higher molybdenum concentrations in these ferritic stainless steels.
This paper explores two issues which are relevant in practical halftoning situations on the CNN universal machine: block processing of large images with small CNN arrays, and the use of no larger than 3/spl times/3 templates. It is shown that block processing can be performed without noticeable boundary artifacts by careful selection of boundary cell values. In this example, a standard 3/spl times/3 halftoning template is used; higher quality halftones can be obtained only by using larger templates. A CNNUM algorithm is introduced which uses only a 3/spl times/3 template but emulates a much larger effective template through an iterative procedure. The method is to discretize the CNN transient in time and then implement the spatial correlations at each time step with a CNN transient. An A-B-template pair was designed for a single CNN transient to approximate a very simple linear filter model of the human visual system. The resulting discrete-time system was analyzed. The iterative procedure is demonstrated to produce a visually pleasing halftone.
view Abstract Citations (42) References (18) Co-Reads Similar Papers Volume Content Graphics Metrics Export Citation NASA/ADS Serendipitous Discovery of a Redshift 4.4 QSO McCarthy, Patrick J. ; Dickinson, Mark ; Filippenko, Alexei V. ; Spinrad, Hyron ; van Breugel, Wil J. M. Abstract We report the serendipitous discovery of an extremely high-redshift quasar (QSO), designated Q2203+29. It was found during long-slit observations of the radio galaxy 3C 441. The QSO spectrum contains strong emission lines of Lyα, N V λ1240, and C IV λ1549, as well as weaker Lyβ, O VI λ1034, Si II λ1262, and Si IV/O IV] λ1400. There is prominent break in the continuum level blueward of Lyα. The derived reshift is 4.406+/-0.005, one of the highest known. Deep broad-band imaging reveals no resolved structure, as expected for a very distant QSO. The r magnitude of the QSO is 20.8. Lyα interference filter imaging shows no emission-line companions or extended emission down to surface brightness levels of 22.5 mag arcsec^-2^. The broad-band images show a faint disk galaxy with z = 0.2, loacted 7" away from the QSO. Our spectra do not exhibit any absorption lines produced by this foreground galaxy. The VLA observations at λ = 20 cm fail to reveal any detectable emission from the QSO to a 3σ upper limit of 1.8 mJy beam^-1^. this is the first serendipitously discovered QSO of any redshift in nearly 5 yr of long-slit CCD spectroscopy of radio sources at Kitt Peak and Lick Observatories. Publication: The Astrophysical Journal Pub Date: May 1988 DOI: 10.1086/185154 Bibcode: 1988ApJ...328L..29M Keywords: Emission Spectra; Lyman Alpha Radiation; Quasars; Red Shift; Line Spectra; Radio Galaxies; Astrophysics; QUASARS; RADIO SOURCES: GALAXIES full text sources ADS | data products NED (3)
