Atomic Force Microscopy of DNA, Nucleoproteins and Cellular Complexes: The Use of Functionalized Substrates

Progress towards rapid and simple characterization of biomolecular samples by scanning probe microscopy is impeded mainly by limitations of the current approach to sample preparation. We are working on approaches based on chemical functionalization of mica. Treatment of mica with aminopropyltriethoxy silane (APTES) makes the surface positively charged (AP-mica) and able to hold DNA in place for imaging, even in water. We have shown that AP-mica is an appropriate substrate for numerous nucleoprotein complexes as well. The AFM images of the complex of DNA with RecA protein are stable and indicate a structural periodicity for this filament. AP-mica holds strongly such large DNA complexes as kinetoplast DNA (kDNA) and is an appropriate substrate for their imaging with AFM. We have further develop this approach for making hydrophobic substrates. Silylation of mica surface with hexamethyldisilazane (Me-mica) allowed us to get AFM images of chlorosomes, an antenna complex isolated from green photosynthetic bacteria. Me-mica may be converted into a positively charged substrate after treatment with water solutions of tetraethylammonium bromide or cetyltrimethylammonium bromide. These activated surfaces show high activity towards binding the DNA molecules

Computer-Conducted Assessment of Life-Change Psychological Stress

118 p.Thesis (Ph.D.)--University of Illinois at Urbana-Champaign, 1976.U of I OnlyRestricted to the U of I community idenfinitely during batch ingest of legacy ETD

In Vitro Digestibility of South Texas Range Plants Using Inoculum from Four Ruminant Species

Differences in the in vitro digestible dry matter (DDM) of 26 native forage species in south Texas were determined using rumen inoculum from white-tailed deer, sheep, goat, and steer. The mean DDM of all forages was significantly different for each animal species (P<.05). Deer was the most efficient overall digestor of forbs, shrubs, and prickly pear. Of the grasses sampled, the goat was the most efficient digestor with the steer second. In overall efficiency of digestion of all forages tested, the deer was highest with 52.5%, goat with 49.2%, sheep with 47.5%, and steer with 46.6%. These data indicate that caution should be exercised when using inoculum from one ruminant species to estimate DDM for another species. Certain plant species were determined to meet the TDN requirements for maintenance levels of the four ruminants.This material was digitized as part of a cooperative project between the Society for Range Management and the University of Arizona Libraries.The Journal of Range Management archives are made available by the Society for Range Management and the University of Arizona Libraries. Contact [email protected] for further information.Migrated from OJS platform August 202

Macro and trace mineral content of selected south Texas deer forages

White-tailed deer (Odocoileus virginianus) derive the majority of their dietary mineral intake from range forages which may be deficient in one or more essential minerals. We have described the macro and trace mineral concentration of 18 shrub, 26 forb, 7 grass, and 1 cactus species, known to occur in south Texas deer diets, collected from the Chaparral Wildlife Management Area in 1974 and 1975. Within each forage class, there were no seasonal differences in calcium (Ca), sodium (Na), potassium (K), or magnesium (Mg) concentrations. Phosphorus (P) concentrations in browse were higher (P less than or equal to 0.05) during the season (0.20%) than during other seasons (0.14-0.16%). Forb P concentrations were greatest during the spring and winter periods (0.26 and 0.29%, respectively), and P levels in grasses (0.24-0.14%) decreased as the forage matured and reached senescence. Shrubs contained less P and K (P less than or equal to 0.01) than either grasses or forbs; whereas, grasses contained lower concentrations of Ca and Mg (P less than or equal to 0.01) than shrubs or forbs. Sodium concentrations did not differ among forage classes. Forbs contained greater (P less than or equal to 0.01) levels of copper (Cu) and zinc (Zn) than grasses or browse, and browse contained less iron (Fe) (P less than or equal to 0.01) than forbs or grasses. Manganese concentrations did not differ among forage classes. There were differences in mineral concentrations among species within forage class. Results suggest concentrations of all minerals except P met or exceeded minimum domestic animal requirements. Managers should provide a diversity of plant species and encourage practices that promote forb growth to provide optimum and nutritional benefits for deer.This material was digitized as part of a cooperative project between the Society for Range Management and the University of Arizona Libraries.The Journal of Range Management archives are made available by the Society for Range Management and the University of Arizona Libraries. Contact [email protected] for further information.Migrated from OJS platform August 202

Low Light Adaptation: Energy Transfer Processes in Different Types of Light Harvesting Complexes from Rhodopseudomonas palustris

Energy transfer processes in photosynthetic light harvesting 2 (LH2) complexes isolated from purple bacterium Rhodopseudomonas palustris grown at different light intensities were studied by ground state and transient absorption spectroscopy. The decomposition of ground state absorption spectra shows contributions from B800 and B850 bacteriochlorophyll (BChl) a rings, the latter component splitting into a low energy and a high energy band in samples grown under low light (LL) conditions. A spectral analysis reveals strong inhomogeneity of the B850 excitons in the LL samples that is well reproduced by an exponential-type distribution. Transient spectra show a bleach of both the low energy and high energy bands, together with the respective blue-shifted exciton-to-biexciton transitions. The different spectral evolutions were analyzed by a global fitting procedure. Energy transfer from B800 to B850 occurs in a mono-exponential process and the rate of this process is only slightly reduced in LL compared to high light samples. In LL samples, spectral relaxation of the B850 exciton follows strongly nonexponential kinetics that can be described by a reduction of the bleach of the high energy excitonic component and a red-shift of the low energetic one. We explain these spectral changes by picosecond exciton relaxation caused by a small coupling parameter of the excitonic splitting of the BChl a molecules to the surrounding bath. The splitting of exciton energy into two excitonic bands in LL complex is most probably caused by heterogenous composition of LH2 apoproteins that gives some of the BChls in the B850 ring B820-like site energies, and causes a disorder in LH2 structure

ACCF/SCAI/AATS/AHA/ASE/ASNC/HFSA/HRS/SCCM/SCCT/SCMR/STS 2012 appropriate use criteria for diagnostic catheterization: American College of Cardiology Foundation Appropriate Use Criteria Task Force Society for Cardiovascular Angiography and Interventions American Association for Thoracic Surgery American Heart Association, American Society of Echocardiography American Society of Nuclear Cardiology Heart Failure Society of America Heart Rhythm Society, Society of Critical Care Medicine Society of C

The American College of Cardiology Foundation, in collaboration with the Society for Cardiovascular Angiography and Interventions and key specialty and subspecialty societies, conducted a review of common clinical scenarios where diagnostic catheterization is frequently considered. The indications (clinical scenarios) were derived from common applications or anticipated uses, as well as from current clinical practice guidelines and results of studies examining the implementation of noninvasive imaging appropriate use criteria. The 166 indications in this document were developed by a diverse writing group and scored by a separate independent technical panel on a scale of 1 to 9, to designate appropriate use (median 7 to 9), uncertain use (median 4 to 6), and inappropriate use (median 1 to 3). Diagnostic catheterization may include several different procedure components. The indications developed focused primarily on 2 aspects of diagnostic catheterization. Many indications focused on the performance of coronary angiography for the detection of coronary artery disease with other procedure components (e.g., hemodynamic measurements, ventriculography) at the discretion of the operator. The majority of the remaining indications focused on hemodynamic measurements to evaluate valvular heart disease, pulmonary hypertension, cardiomyopathy, and other conditions, with the use of coronary angiography at the discretion of the operator. Seventy-five indications were rated as appropriate, 49 were rated as uncertain, and 42 were rated as inappropriate. The appropriate use criteria for diagnostic catheterization have the potential to impact physician decision making, healthcare delivery, and reimbursement policy. Furthermore, recognition of uncertain clinical scenarios facilitates identification of areas that would benefit from future research. © 2012 Wiley Periodicals, Inc