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31.
LJ Brando R Yolken MM Herman JE Kleinman CA Ross EF Torrey 《Canadian Metallurgical Quarterly》1996,6(1):1-5
This study reports our preliminary experience with interstitial radiofrequencies in the treatment of urological malignancies. Bipolar radiofrequency was interstitially delivered in four freshly removed human kidneys in an ex-vivo model. The kidney was perfused ex-vivo with 37 degrees C saline in order to mimic physiological conditions. Large reproducible and controlled lesions (hypereosinophilia and pyknosis) were observed in the parenchyma between the active needles. Further animal and human clinical studies are planned to precise the place of bipolar RF in the treatment or urological malignancies, and especially in kidney tumors. 相似文献
32.
Augustine C Ogbonna Samuel KC Obi Bartholomew N Okolo Frederick JC Odibo 《Journal of the science of food and agriculture》2004,84(2):113-120
A cysteine proteinase from sorghum malt variety SK5912 was purified by a combination of 4 M sucrose fractionation, ion‐exchange chromatography on Q‐ and S‐Sepharose (fast flow), gel filtration chromatography on Sephadex G‐100 and hydrophobic interaction chromatography on Phenyl Sepharose CL‐4B. The enzyme was purified 8.4‐fold to give a 13.4% yield relative to the total activity in the crude extract and a final specific activity of 2057.1 U mg?1 protein. SDS—PAGE revealed two migrating protein bands corresponding to apparent relative molecular masses of 55 and 62 kDa, respectively. The enzyme was optimally active at pH 6.0 and 50 °C, not influenced across a relatively broad pH range of 5.0–8.0 and retained over 60% activity at 70 °C after 30‐min incubation. It was highly significantly (P < 0.001) inhibited by Hg2+, appreciably (P < 0.01) inhibited by Ag+, Ba2+ and Pb2+ but highly significantly (P < 0.001) activated by Co2+, Mn2+ and Sr2+. The proteinase was equally highly significantly (P < 0.001) inhibited by both iodoacetate and p‐chloromercuribenzoate and hydrolysed casein to give the following kinetic constants: Km = 0.33 mg ml?1; Vmax = 0.08 µmol ml?1 min?1. Copyright © 2004 Society of Chemical Industry 相似文献
33.
S. Friedemann T. Westerkamp M. Brando N. Oeschler P. Gegenwart C. Krellner C. Geibel S. MaQuilon Z. Fisk F. Steglich S. Wirth 《Journal of Low Temperature Physics》2010,161(1-2):67-82
The unconventional nature of the quantum criticality in YbRh2Si2 is highlighted on the basis of magnetoresistivity and susceptibility measurements. Results obtained under chemical pressure realized by isoelectronic substitution on the rhodium site are presented. These results illustrate the position of the T?-line associated with a breakdown of the Kondo effect near the antiferromagnetic instability in the low-temperature phase diagram. Whereas at zero temperature the Kondo breakdown and the antiferromagnetic quantum critical point coincide in the proximity of the stoichiometric compound, they are seen to be detached under chemical pressure: For positive chemical pressure the magnetically ordered phase extends beyond the T ?(B)-line. For sufficiently high negative pressure the T ?(B)-line is separated from the magnetically ordered phase. From our detailed analysis we infer that the coincidence is retained at small iridium concentrations, i.e., at small negative chemical pressure. We outline further measurements which may help to clarify the detailed behavior of the two instabilities. 相似文献
34.
Daniel Odermatt Anatoly Gitelson Vittorio Ernesto Brando Michael Schaepman 《Remote sensing of environment》2012
We provide a comprehensive overview of water constituent retrieval algorithms and underlying definitions and models for optically deep and complex (i.e. case 2) waters using earth observation data. The performance of constituent retrieval algorithms is assessed based on matchup validation experiments published between January 2006 and May 2011. Validation practices range from singular vicarious calibration experiments to comparisons using extensive in situ time series. Band arithmetic and spectral inversion algorithms for all water types are classified using a method based scheme that supports the interpretation of algorithm validity ranges. Based on these ranges we discuss groups of similar algorithms in view of their strengths and weaknesses. Such quantitative literature analysis reveals clear application boundaries. With regard to chlorophyll retrieval, validation of blue–green band ratios in coastal waters is limited to oligotrophic, predominantly ocean waters, while red-NIR ratios apply only at more than 10 mg/m3. Spectral inversion techniques — although not validated to the same extent — are necessary to cover all other conditions. Suspended matter retrieval is the least critical, as long as the wavelengths used in empirical models are increased with concentrations. The retrieval of dissolved organic matter however remains relatively inaccurate and inconsistent, with large differences in the accuracy of comparable methods in similar validation experiments. We conclude that substantial progress has been made in understanding and improving retrieval of constituents in optically deep and complex waters, enabling specific solutions to almost any type of optically complex water. Further validation and intercomparison of spectral inversion procedures are however needed to learn if solutions with a larger validity range are feasible. 相似文献
35.
TD Nguyen MW Moody M Steinhoff C Okolo DS Koh NW Bunnett 《Canadian Metallurgical Quarterly》1999,103(2):261-269
Proteinase-activated receptor-2 (PAR-2) is a G protein-coupled receptor that is cleaved by trypsin within the NH2-terminus, exposing a tethered ligand that binds and activates the receptor. We examined the secretory effects of trypsin, mediated through PAR-2, on well-differentiated nontransformed dog pancreatic duct epithelial cells (PDEC). Trypsin and activating peptide (AP or SLIGRL-NH2, corresponding to the PAR-2 tethered ligand) stimulated both an 125I- efflux inhibited by Ca2+-activated Cl- channel inhibitors and a 86Rb+ efflux inhibited by a Ca2+-activated K+ channel inhibitor. The reverse peptide (LRGILS-NH2) and inhibited trypsin were inactive. Thrombin had no effect, suggesting absence of PAR-1, PAR-3, or PAR-4. In Ussing chambers, trypsin and AP stimulated a short-circuit current from the basolateral, but not apical, surface of PDEC monolayers. In monolayers permeabilized basolaterally or apically with nystatin, AP activated apical Cl- and basolateral K+ conductances. PAR-2 agonists increased [Ca2+]i in PDEC, and the calcium chelator BAPTA inhibited the secretory effects of AP. PAR-2 expression on dog pancreatic ducts and PDEC was verified by immunofluorescence. Thus, trypsin interacts with basolateral PAR-2 to increase [Ca2+]i and activate ion channels in PDEC. In pancreatitis, when trypsinogen is prematurely activated, PAR-2-mediated ductal secretion may promote clearance of toxins and debris. 相似文献
36.
B.N. Okolo O.C. Amadi A.N. Moneke T.N. Nwagu C.I. Nnamchi 《Journal of the Institute of Brewing》2020,126(1):46-52
The sugar profile of wort from laboratory malted barley, malted sorghum, unmalted barley and unmalted sorghum grains mashed with commercial enzyme preparations were studied. Similar levels of glucose to maltose (1:7) were observed in wort of malted barley and malted sorghum. Mashing barley or sorghum grains with commercial enzymes changed the glucose to maltose ratio in both worts, with a greater change in wort from sorghum grains. Although hydrolysis with commercial enzymes released more glucose from maltose in sorghum wort, the same treatment retained more maltose in barley wort. Adding malted barley to sorghum grains mashed with commercial enzymes restored the glucose to maltose ratio in sorghum mash. Fermentation of wort produced from all barley malt (ABM) mash and commercial enzyme/barley malt/sorghum adjunct (CEBMSA) mash of similar wort gravity was also studied. ABM and CEBMSA worts exhibited similar glucose to maltose ratios and similar amino acid spectra. However, ABM released more individual amino acids and five times more proline than wort from commercial enzyme/barley malt/sorghum adjunct. ABM produced 27% more glucose and 7% more maltose than CEBMSA. After fermentation, ABM mash produced 9.45% ABV whilst commercial enzyme/barley malt/sorghum adjunct mash produced 9.06% ABV. Restoration of the glucose/maltose ratio in the CEBMSA mash produced wort with a sugar balance required for high gravity brewing. © 2020 The Institute of Brewing & Distilling 相似文献
37.
With nothing into the cold – Dilution cryostats and vacuum equipment for quantum computers Dilution cryostats are used for various applications, for example on a large scale for the development of quantum computers, or for basic research in solid‐state physics. Vacuum technology plays a central role in generating the low temperatures. This article highlights the necessary features of vacuum pumps that circulate the so‐called 3He/4He mixture. In addition to the results of a field test with a multistage Roots pump, the use of pumping systems is discussed. 相似文献
38.
JW Gratama A Orfao D Barnett B Brando A Huber G Janossy HE Johnsen M Keeney GE Marti F Preijers G Rothe S Serke DR Sutherland CE Van der Schoot G Schmitz S Papa 《Canadian Metallurgical Quarterly》1998,34(3):128-142
The need for a rapid and reliable marker for the engraftment potential of hematopoietic stem and progenitor cell (HPC) transplants has led to the development of flow cytometric assays to quantitate such cells on the basis of their expression of CD34. The variability associated with enumeration of low-frequency cells (i.e., as low as 0.1% or 5 cells/microl) is exceedingly large, but recent developments have improved the accuracy and precision of the assay. Here, we review and compare the major techniques. Based on the current state of the art, we recommend 1) bright fluorochrome conjugates of class II or III monoclonal antibodies (mAbs) that detect all glycoforms of CD34, 2) use of a vital nucleic acid dye to exclude platelets, unlysed red cells, and debris or use of 7-amino actinomycin D to exclude dead cells during data acquisition, 3) counterstaining with CD45 mAb to be included in the definition of HPC, 4) during list mode data analysis, Boolean gating to resolve the CD34+ HPCs from irrelevant cell populations on the basis of the low levels of CD45 expression and low sideward light-scatter signals of HPCs, 5) inclusion of CD34dim and CD34bright populations in the CD34+ cell count, 6) omission of the negative control staining, and 7) for apheresis products, enumeration of at least 100 CD34+ cells to ensure a 10% precision. Unresolved technical questions are 1) the replacement of conventional dual-platform by single-platform assay formats, i.e., derivation of absolute CD34+ cell counts from a single flow cytometric assessment instead of from combined flow cytometer (percent CD34+) and hematology analyzer (absolute leukocyte count) data, 2) the cross-calibration of the available single-platform assays, and 3) the optimal method for sample preparation. An important clinical question to be addressed is the definition of the precise phenotypes and required numbers of HPCs responsible for short- and long-term recovery to optimize HPC transplant strategies. 相似文献
39.
Mobilisation of sorghum storage reserve proteins by steeping in alkaline liquor for 48 h under four different regimes was evaluated. Germination was for 4 days at 30°C. Cold water soluble protein (CWS-protein), CWS-protein modification index, total non protein nitrogen (TNPN), peptide accumulation, FAN, endo- and exo-protease activities—all key indicators of protein mobilisation were highly significantly affected by steep regime, steep liquor and cultivar as well as their pairwise interactions. Mean FAN and TNPN were significantly higher (P < 0.0005) for malts derived from alkaline steep liquor except for KSV 8 which exhibited significant inhibition of TNPN development. Similarly, alkaline steeping promoted protein solubilisation and CWS-protein modification. While parallel improvements in amylolysis and proteolysis were recorded for ICSV 400, proteolysis in KSV 8 and SK 5912 seemed more enhanced except for SK 5912 exposed to air rest cycles. Steeping in alkaline liquor also caused significant repression of the proteases in KSV 8. Conversely, steeping SK 5912 under similar conditions promoted rather than inhibited development of these enzymes. Poor correlation between protein degradation products and enzyme development suggest major roles for factors other than proteolysis in sorghum reserve protein mobilisation. 相似文献
40.
Glenn Campbell Stuart R. Phinn Vittorio E. Brando 《Remote sensing of environment》2011,115(9):2402-2414
The purpose of this study was to investigate how semi-analytical inversion techniques developed for the remote sensing of water quality parameters (chlorophyll a, tripton and coloured dissolved organic matter (CDOM)) in inland waters could be adapted or improved for application to Australian tropical and sub-tropical water bodies. The Matrix Inversion Method (MIM) with a semi-analytic model of the anisotropy of the in-water light field was applied to MERIS images of Burdekin Falls Dam, Australia, a tropical freshwater impoundment. Specific attention was required to improve the atmospheric correction of the MERIS data. The performance of the conventional three band exact solution of the MIM was compared to that of over-determined solutions that used constant and differential weighting for each sensor band.The results of the application of the MIM algorithm showed that the best weighting scheme had a mean chlorophyll a retrieval difference of 1.0 μgl− 1, the three band direct matrix inversion scheme had a mean difference of 4.2 μgl− 1 and the constant weight scheme had a mean difference of 5.5 μgl− 1. For tripton, the best performed weighting scheme had a mean difference of 1.2 mgl− 1, the three band scheme had a mean difference of 3.4 mgl− 1 and the constant weight scheme had a mean difference of 1.8 mgl− 1. For the CDOM retrieval, the mean difference was found to be 0.12 m− 1 for the best performed weighting scheme, 0.25 m− 1 for the three band scheme and 0.52 m− 1 for the constant weight scheme. It was found that significant improvements in the accuracy and precision of retrieved water quality parameter values can be obtained by using differentially weighted, over-determined systems of equations, rather than exact solutions. These more reliable estimates of water quality parameters will allow water resource managers to improve their monitoring regimes. 相似文献