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131.
James Tickner Raffaele Bencardino Greg Roach 《Nuclear instruments & methods in physics research. Section B, Beam interactions with materials and atoms》2010,268(2):99-3128
Activation yields have been measured for (γ,n) reactions of the elements Ru, Rh, Pd, Ir and Pt. Metallic foils of natural isotopic composition were irradiated using Bremsstrahlung radiation produced from an electron linear accelerator operated with electron beam energies in the range 11-14 MeV. Activation products, including both unstable ground states and metastates were measured using a high-purity germanium detector. Cross-sections were estimated from the yield data by assuming a simple two-parameter model for the shape of the cross-section with energy. 相似文献
132.
Raquel Rodríguez‐Solana Jorge Dias Carlier Maria Clara Costa Anabela Romano 《Journal of the Institute of Brewing》2018,124(3):300-309
Carob pod, fig and almond liqueurs are produced in various Mediterranean regions. This work reports the mineral content of these traditional beverages and evaluates the influence of the raw material. Twenty‐five fruit liqueurs from 16 producers were analysed. A simple open‐vessel sample mineralization by wet digestion using nitric acid–hydrogen peroxide (1:1) was used before spectrometric analysis. Nine essential elements (Cu, Ca, Mg, Na, K, Fe, Zn, Mn and P) and two non‐essentials (Cd and Pb) were quantified by microwave plasma–atomic emission spectrometry (MP‐AES). Carob liqueur presented the broader profile of minerals and was the only fruit liqueur containing iron (72.7% of samples), phosphorous, manganese and low levels of lead (in two of the 11 samples). Conversely, almond liqueurs contained the lowest mineral content with only five elements detected. Fruit liqueurs showed variability in mineral content even within the same liqueur, presumably as a consequence of the different manufacturing processes. Despite this variability, application of principal component analysis to essential mineral concentrations (K, Na, Ca, Mg, Mn, Fe and Zn) resulted in satisfactory classification (PC1 and PC2 accounting for 78.5% of the total variance) of the Portuguese liqueurs evaluated. Copyright © 2018 The Institute of Brewing & Distilling 相似文献
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136.
Angelucci G Meloni M Merella P Sardu F Madeddu S Marrosu R Petza F Salati F 《Journal of food protection》2011,74(10):1769-1775
A study was carried out on the presence of Anisakis and Hysterothylacium larvae in fish and cephalopods caught in Sardinian waters. A total of 369 specimens of 24 different species of teleosts and 5 species of cephalopods were collected from different fishing areas of Sardinia. Larvae were detected and isolated by both visual inspection and enzymatic digestion. These methods allowed Anisakis type I and type II third-stage larvae and Hysterothylacium third- and fourth-stage larvae to be detected. The prevalence, mean intensity, and mean abundance were calculated. The results obtained showed the highest prevalence of Anisakidae in Zeus faber (100%) and of Anisakis in Micromesistius poutassou (87.5%). The highest prevalence of Anisakis type I larvae was in M. poutassou (81.2%), and that of Anisakis type II larvae was in Todarodes sagittatus (20%). The highest values for prevalence, mean intensity, and mean abundance for Hysterothylacium were found in Z. faber. These prevalences and the mean intensity and abundance were higher than those reported by different authors in other Mediterranean areas. This may be because the enzymatic digestive method used in this research resulted in higher recovery levels. The data suggest that Sardinia may be a high-risk area for zoonotic diseases and that measures such as information campaigns, aimed at both sanitary service personnel and consumers, should be employed to limit the spread of such zoonosis. 相似文献
137.
PR Romano F Zhang SL Tan MT Garcia-Barrio MG Katze TE Dever AG Hinnebusch 《Canadian Metallurgical Quarterly》1998,18(12):7304-7316
The human double-stranded RNA (dsRNA)-dependent protein kinase PKR inhibits protein synthesis by phosphorylating translation initiation factor 2alpha (eIF2alpha). Vaccinia virus E3L encodes a dsRNA binding protein that inhibits PKR in virus-infected cells, presumably by sequestering dsRNA activators. Expression of PKR in Saccharomyces cerevisiae inhibits protein synthesis by phosphorylation of eIF2alpha, dependent on its two dsRNA binding motifs (DRBMs). We found that expression of E3 in yeast overcomes the lethal effect of PKR in a manner requiring key residues (Lys-167 and Arg-168) needed for dsRNA binding by E3 in vitro. Unexpectedly, the N-terminal half of E3, and residue Trp-66 in particular, also is required for anti-PKR function. Because the E3 N-terminal region does not contribute to dsRNA binding in vitro, it appears that sequestering dsRNA is not the sole function of E3 needed for inhibition of PKR. This conclusion was supported by the fact that E3 activity was antagonized, not augmented, by overexpressing the catalytically defective PKR-K296R protein containing functional DRBMs. Coimmunoprecipitation experiments showed that a majority of PKR in yeast extracts was in a complex with E3, whose formation was completely dependent on the dsRNA binding activity of E3 and enhanced by the N-terminal half of E3. In yeast two-hybrid assays and in vitro protein binding experiments, segments of E3 and PKR containing their respective DRBMs interacted in a manner requiring E3 residues Lys-167 and Arg-168. We also detected interactions between PKR and the N-terminal half of E3 in the yeast two-hybrid and lambda repressor dimerization assays. In the latter case, the N-terminal half of E3 interacted with the kinase domain of PKR, dependent on E3 residue Trp-66. We propose that effective inhibition of PKR in yeast requires formation of an E3-PKR-dsRNA complex, in which the N-terminal half of E3 physically interacts with the protein kinase domain of PKR. 相似文献
138.
M Amichetti G Fellin A Bolner L Busana G Pani M Romano M Scillieri S Maluta 《Canadian Metallurgical Quarterly》1994,80(2):141-145
AIMS AND BACKGROUND: Pure testicular seminoma has historically been treated with post-orchidectomy radiation therapy with excellent results. Recently, several aspects of the treatment of stage I seminoma have been questioned. We assessed long-term results and toxicity of patients with pure testicular seminoma treated at the Department of Radiation Oncology of S. Chiara Hospital, Trento, METHODS: From 1953 to 1987, 102 patients with stage I pure testicular seminoma were given megavoltage irradiation with curative intent. All patients had a minimum follow-up of 3 years (maximum 37 years, median 13 years). They received a mean para-aortic/pelvic dose of 33.07 Gy (range 23.70-45.20 Gy) with different doses and fields reflecting the change in techniques over a long period of time. RESULTS: The cause-specific actuarial survival at 30 years was 99% and crude survival 67%. One patient had an out-field relapse (inguinal) after a few months and was cured with radiotherapy and chemotherapy. Another patient relapsed with widespread metastases and died after 1 year of progressive disease. Early toxycity was mild and the treatment was well tolerated. Late side effects were reported in 8/102 patients. CONCLUSIONS: In our series adjuvant radiation therapy resulted in cure rates corresponding to those reported in the literature. The 30-year actuarial survival of 99% was extremely good and the toxicity of the treatment was mild. Post-orchidectomy radiation to the para-aortic and ipsilateral pelvic nodes is a safe and effective method of preventing recurrences and is currently to be considered the treatment of choice in stage I testicular seminoma. 相似文献
139.
D D'Antonio A Mazzoni A Iacone B Violante MA Capuani F Schioppa F Romano 《Canadian Metallurgical Quarterly》1996,34(3):753-755
Blastoschizomyces capitatus strains resistant to fluconazole were isolated in three cancer patients. All of the strains had identical genomic DNA restriction profiles. Our findings give evidence for the emergence of fluconazole-resistant B. capitatus and suggest a nosocomial acquisition emanating from a common source within the hospital environment. 相似文献
140.
Kyungjung Kim Sarkar T.K. Salazar-Palma M. Romano S.-L. 《Antennas and Propagation, IEEE Transactions on》2002,50(3):277-283
Wavelet-like transformations have been used in the past to compress dense large matrices into a sparse system. However, they generally are implemented through a finite impulse response filter realized through the formulation of Daubechies (1992). A method is proposed to use a very high order filter (namely an ideal one) and use the computationally efficient fast Fourier transform (FFT) to carry out the multiresolution analysis. The goal here is to reduce the redundancy in the system and also guarantee that the wavelet coefficients drop off much faster. Hence, the efficiency of the new procedure becomes clear for very high order filters. The advantage of the FFT-based procedure utilizing ideal filters is that it can be computationally efficient and for very large matrices may yield a sparse matrix. However, this is achieved, as well known in the literature, at the expense of robustness, which may lead to a larger reconstruction error due to the presence of the Gibb's phenomenon. Numerical examples are presented to illustrate the efficiency of this procedure as conjectured in the literature 相似文献