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101.
The Status and Future of Synchrotron Based Infrared Imaging Workshop convened at the Waisman Center at UW Madison on October 7, 2010. The goal of the workshop was to bring together imaging scientists from many disciplines, as well as data management and industry experts. 相似文献
102.
Quantification of neurons in Alzheimer and control brains with ex vivo high resolution magic angle spinning proton magnetic resonance spectroscopy and stereology 总被引:17,自引:0,他引:17
Samples from human brains were examined with both stereologic methods for neuronal counting and high resolution magic angle spinning (HRMAS) proton magnetic resonance spectroscopy (1HMRS) for quantification of cellular metabolites. A statistically significant linear correlation between neuronal density and the concentration of N-acetylaspartate (NAA) in the superior temporal sulcus (STS) area was observed. Although NAA has been widely utilized as a neuronal marker in in vivo MRS, an emerging sub-discipline of diagnostic neuroradiology, the experimental proof of the unilateral relationship between NAA and neurons has yet to be confirmed. The observed correlation provides experimental evidence that NAA concentration is proportional to the neuronal density. Metabolite ratios measured from the STS area were compared to those from frontal association cortex for their sensitivities in differentiating Alzheimer disease brains from control brains. 相似文献
103.
Raymond Ko Chad Shew Sharman Perera Baki Sadi Kristine Mattson Kathy Nielsen David Kelly Ed Waller Chunsheng Li 《Journal of Radioanalytical and Nuclear Chemistry》2014,300(1):147-152
Nasal swabs and facial swipes have been used to screen potential internal radioactive contamination for decades. However, the ratio between the lung intake and the activity on a swab or a swipe varies according to the nature of the contaminant involved and the exposure conditions such as particle sizes of the contaminant and the humidity in the air. This paper reports the experimental results using stable La2O3 as an analog for actinide oxides, focusing on the most important parameters such as humidity, plume velocity, and facial condition at a fixed room temperature of 23 ± 2 °C. The results showed that the effects of humidity, plume velocity, and facial condition vary more on orofacial swipe/lung deposition ratios compared to nasal swab/lung deposition ratios. The amounts on nasal swabs tended to show smaller change with respect to parameters such as plume velocity, humidity, and skin moisture. The amounts on orofacial swipes varied by a factor of 10–15 among the samples collected across all parameters. Such variability would be expected to be even greater in a real-world scenario with a larger range of physiological and environmental conditions. 相似文献
104.
We show that the zeros of the hypergeometric polynomials
,
, cluster on the loop of the lemniscate
as
. We also state the equations of the curves on which the zeros of
, lie asymptotically as
. Auxiliary results for the asymptotic zero distribution of other functions related to hypergeometric polynomials are proved,
including Jacobi polynomials with varying parameters and associated Legendre functions. Graphical evidence is provided using
Mathematica.
This revised version was published online in June 2006 with corrections to the Cover Date. 相似文献
105.
Lawrence W. Baggett Herbert A. Medina Kathy D. Merrill 《Journal of Fourier Analysis and Applications》1999,5(6):563-573
An abstract formulation of generalized multiresolution analyses is presented, and those GMRAs that come from multiwavelets are characterized. As an application of this abstract formulation, a constructive procedure is developed, which produces all wavelet sets in n
relative to an integral expansive matrix. 相似文献
106.
Jack E. Baldwin Bulbul Chakravarti Leslie D. Field John A. Murphy Kathy R. Whitten Sir Edward P. Abraham Gamini Jayatilake 《Tetrahedron》1982,38(18):2773-2776
The title peptide () has been synthesized and incubated with an active cell-free extract of , no conversion to active antibiotics was observed; however on co-incubation with the Arnstein tripeptide (ACV) (), strong inhibition of the conversion of ACV to isopenicillin N was observed. 相似文献
107.
Wayne?DimechEmail author Sandy?Walker Darren?Jardine Scott?Read Kathy?Smeh Marina?Karakaltsas Bradley?Dent Elizabeth?M.?Dax 《Accreditation and quality assurance》2004,9(3):148-151
The National Serology Reference Laboratory, Australia (NRL) has quality assured the serology for high risk blood-borne infections since 1985, commencing with anti-Human Immunodeficiency Virus (HIV) enzyme immunoassays and later extending the programmes to other blood-borne virus testing and to nucleic acid testing. A quality control (QC) programme was considered the most appropriate manner in which to achieve real-time monitoring. An Internet-based application, EDCNet, facilitates the entry of results of QC sample testing and returns the analysed results instantaneously. Results can be displayed in a variety of tables and charts, so that QC results from blood service and diagnostic laboratories can be monitored. Comparison of results between laboratories using the same system offers monitoring of accuracy, while within-laboratory comparisons offer monitoring of the assay precision. More than 200,000 data points were submitted to EDCNet in 2002 from blood service laboratories as well as from diagnostic laboratories. Analysis of reagent batch variability was determined, e.g. the coefficient of variation between batches of seven assays used to detect anti-hepatitis C virus (HCV) antibodies ranged from 4.9% to 21.6%. Using EDCNet, laboratories can monitor both precision and accuracy of results by comparison with the results of other laboratories. The system may be a highly cost-effective method for maintaining quality.
相似文献
Wayne DimechEmail: Phone: +61-3-9418 1111Fax: +61-3-9418 1155 |
108.
Kathryn Barnes-Burroughs Edward E. Anderson Thomas Hughes William Y. Lan Karl Dent Sue Arnold Gerald Dolter Kathy McNeil 《Journal of voice》2007,21(6):689-698
The purpose of this investigation was to ascertain the pedagogical viability of computer-generated melodic contour mapping systems in the classical singing studio, as perceived by their resulting effect (if any) on vocal timbre when a singer's head and neck remained in a normal singing posture. The evaluation of data gathered during the course of the study indicates that the development of consistent vocal timbre produced by the classical singing student may be enhanced through visual/kinesthetic response to melodic contour inversion mapping, as it balances the singer's perception of melodic intervals in standard musical notation. Unexpectedly, it was discovered that the system, in its natural melodic contour mode, may also be useful for teaching a student to sing a consistent legato line. The results of the study also suggest that the continued development of this new technology for the general teaching studio, designed to address standard musical notation and a singer's visual/kinesthetic response to it, may indeed be useful. 相似文献
109.
Packer AP Larivière D Li C Chen M Fawcett A Nielsen K Mattson K Chatt A Scriver C Erhardt LS 《Analytica chimica acta》2007,590(2):166-172
This work describes the optimization of a cloud point extraction (CPE) method for casein proteins from cow milk samples. To promote phase separation, polyoxyethylene(8) isooctylphenyl ether (Triton® X-114) and sodium chloride (NaCl) were used as nonionic surfactant and electrolyte, respectively. Using multivariate studies, four major CPE variables were evaluated: Triton® X-114 concentration, sample volume, NaCl concentration, and pH. The results show that surfactant concentration and sample volume were the main variable affecting the CPE process, with the following optimized parameters: 1% (w/v) Triton® X-114 concentration, 50 μL of sample volume, 6% (w/v) NaCl concentration and extractions carried out at pH 7.0. At these conditions, 923 ± 66 and 67 ± 2 μg mL−1 of total protein were found in the surfactant-rich and surfactant-poor phases, respectively. Finally, matrix-assisted laser desorption ionization-time of flight mass spectrometry (MALDI-TOF MS) was then used to evaluate those target proteins (s1-casein, s2-casein and β-casein) separation as well as to check the efficiency of the extraction procedure, making a fingerprint of those target proteins possible. 相似文献
110.
Bruce MI Costuas K Davin T Halet JF Kramarczuk KA Low PJ Nicholson BK Perkins GJ Roberts RL Skelton BW Smith ME White AH 《Dalton transactions (Cambridge, England : 2003)》2007,(46):5387-5399
The sequential conversion of [OsBr(cod)Cp*] (9) to [OsBr(dppe)Cp*] (10), [Os([=C=CH2)(dppe)Cp*]PF6 ([11]PF6), [Os(C triple bond CH)(dppe)Cp*] (12), [{Os(dppe)Cp*}2{mu-(=C=CH-CH=C=)}][PF6]2 ([13](PF6)2) and finally [{Os(dppe)Cp*}(2)(mu-C triple bond CC triple bond C)] (14) has been used to make the third member of the triad [{M(dppe)Cp*}2(mu-C triple bond CC triple bond C)] (M = Fe, Ru, Os). The molecular structures of []PF6, 12 and 14, together with those of the related osmium complexes [Os(NCMe)(dppe)Cp*]PF6 ([15]PF6) and [Os(C triple bond CPh)(dppe)Cp*] (16), have been determined by single-crystal X-ray diffraction studies. Comparison of the redox properties of 14 with those of its iron and ruthenium congeners shows that the first oxidation potential E1 varies as: Fe approximately Os < Ru. Whereas the Fe complex has been shown to undergo three sequential 1-electron oxidation processes within conventional electrochemical solvent windows, the Ru and Os compounds undergo no fewer than four sequential oxidation events giving rise to a five-membered series of redox related complexes [{M(dppe)Cp*}2(mu-C4)]n+ (n = 0, 1, 2, 3 and 4), the osmium derivatives being obtained at considerably lower potentials than the ruthenium analogues. These results are complimented by DFT and DT DFT calculations. 相似文献