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31.
This study assessed the accuracy of 16 commercial and three self-produced kits and drew the basis for using an external quality control (EQC) system. The commercial kits were mainly developed for blood sex steroid determination in humans but also have been used in cattle. Parallelism, recovery and precision tests were performed for progesterone (P4), testosterone (T) and oestradiol (E2) assays. Moreover, anonymous QC samples were sent to be analysed to some Italian laboratories. All kits showed a fair degree of parallelism (P < 0.01), even though 2/7 kits for T and 1/6 kits for E2 determination showed a regression coefficient (r2) lower than 0.98. For P4, an acceptable range of accuracy was achieved in the recovery test only by 1/6 kits; two kits showed fair or great overestimation and two kits considerable underestimation. For T, an acceptable range of accuracy was achieved only by 1/7 kits. For E2, 4/6 kits presented a variable degree of underestimation and two kits showed great overestimation. In the intra-assay precision test quite good repeatability was achieved only using samples with high hormone concentrations. While assaying samples with low concentrations we found a number of RSD > 10%. Moreover, the laboratories participating in the EQC produced statistically different (P < 0.05) results, particularly for high and medium concentrations. In conclusion, the use of commercial kits for screening naturally occurring sex steroid concentrations in cattle blood, in the case of suspected illegal treatments, requires preventive validation procedures and the development of an opportune EQC system. 相似文献
32.
Abrams GS Adolphsen CE Averill D Ballam J Barish BC Barklow T Barnett BA Bartelt J Bethke S Blockus D Bonvicini G Boyarski A Brabson B Breakstone A Bulos F Burchat PR Burke DL Cence RJ Chapman J Chmeissani M Cords D Coupal DP Dauncey P DeStaebler HC Dorfan DE Dorfan JM Drewer DC Elia R Feldman GJ Fernandes D Field RC Ford WT Fordham C Frey R Fujino D Gan KK Gero E Gidal G Glanzman T Goldhaber G Gomez Cadenas JJ Gratta G Grindhammer G Grosse-Wiesmann P Hanson G Harr R Harral B Harris FA 《Physical review letters》1989,63(22):2447-2451
33.
R. Marchesini S. Tomatis C. Bartoli A. Bono C. Clemente C. Cupeta I. Del Prato E. Pignoli A. E. Sichirollo N. Cascinelli 《Photochemistry and photobiology》1995,62(1):151-154
Abstract— Reflectance spectroscopy, which allows an objective evaluation of the color of surfaces, has recently been proposed as a useful tool to discriminate cutaneous melanoma from other pigmented cutaneous lesions. A novel spectrophotometric system based on the use of a charge coupled device camera provided with a set of interference filters has been developed to acquire images of cutaneous pigmented lesions at selected wavelengths ranging from 420 to 1040 nm. For each filter, an image was captured, digitized by a frame grabber and stored in a personal computer to perform off-line data handling. Reflectance images were acquired of 22 cutaneous pigmented lesions including melanoma and dysplastic, compound and junctional nevus. From each spectral image, three parameters, i.e. mean reflectance, variegation index and lesion area, were derived at the corresponding wavelength. The wavelength dependence of the three parameters was significantly different when melanoma was compared to the other investigated lesions. Although preliminary, our results suggest that telespectrophotometry gives useful information and could be utilized as an aid in the clinical diagnosis of cutaneous pigmented lesions. 相似文献
34.
35.
D. Bono J. Hartig M. Huber H. Schnöckel L. J. de Jongh 《Journal of Cluster Science》2007,18(1):319-331
We present an 27Al NMR study of the metal cluster compound Al50Cp*12 which is composed of (identical) Al50 clusters, each surrounded by a Cp* ligand shell, and arranged in a crystalline 3D array (here Cp* = pentamethylcyclopentadienyl = C5(CH3)5). The compound is found to be non-conducting, the nuclear spin-lattice relaxation in the temperature range 100–300 K being
predominantly due to reorientational motions of the Cp* rings. These lead to a pronounced maximum in the relaxation rate at
T ∼ 170 K, corresponding to an activation energy of about 850 K. Data for the related compound Al4Cp*4, containing very much smaller Al4 clusters are also presented. A comparison is drawn with the quadrupolar relaxation recently observed for the non-conducting
fraction of Ga84 molecules in the metal cluster compound Ga84[N(SiMe3)2]20-Li6Br2(thf)20·2toluene.
It is our pleasure to dedicate this paper to our colleague professor Günter Schmid at the occasion of his 70th birthday. 相似文献
36.
37.
S. Colantonio M. Benvenuti M.G. Di Bono G. Pieri O. Salvetti 《Infrared Physics & Technology》2007,49(3):266-271
In this paper, we deal with the problem of real-time detection, recognition and tracking of moving objects in open and unknown environments using an infrared (IR) and visible vision system. A thermo-camera and two stereo visible-cameras synchronized are used to acquire multi-source information: three-dimensional data about target geometry and its thermal information are combined to improve the robustness of the tracking procedure. Firstly, target detection is performed by extracting its characteristic features from the images and then by storing the computed parameters on a specific database; secondly, the tracking task is carried on using two different computational approaches. A Hierarchical Artificial Neural Network (HANN) is used during active tracking for the recognition of the actual target, while, when partial occlusions or masking occur, a database retrieval method is used to support the search of the correct target followed. A prototype has been tested on case studies regarding the identification and tracking of animals moving at night in an open environment, and the surveillance of known scenes for unauthorized access control. 相似文献
38.
Ohsten Rasmussen M Hogg B Bono JJ Samain E Driguez H 《Organic & biomolecular chemistry》2004,2(13):1908-1910
Sulfonated and non-sulfonated lipo-chitooligosaccharides involved in Sinorhizobium meliloti-legume symbiosis are efficiently obtained on a multi mg scale by a 2-step procedure combining biotechnological and chemical approaches. 相似文献
39.
Bono D Mendels P Collin G Blanchard N Bert F Amato A Baines C Hillier AD 《Physical review letters》2004,93(18):187201
We present muSR experiments in the S=3/2 kagomé bilayer compound Ba(2)Sn(2)ZnGa(10-7p)Cr(7p)O22 [BSZCGO(p)] and compare it to the isostructural SrCr(9p)Ga(12-9p)O19 [SCGO(p)], including for the latter new results for p > or =0.89. Quantum-dynamical low energy magnetic excitations are evidenced in this novel compound. We study the evolution of the muon relaxation rate with p, T, and field. A phenomenological model for the muon relaxation based on sporadic dynamics due to spin excitations in a singlet sea proposed by Uemura et al. is extended to all fields and T range. Its connection to the RVB picture is discussed, and we argue that such coherent states might mediate the interactions between "impurities" which induce the spin glass freezing. 相似文献
40.
A. Colin P. Morin F. Cacho H. Bono R. Beneyton D. Mathiot E. Fogarassy 《Applied Physics A: Materials Science & Processing》2011,104(2):517-527
We present a study of the temperature non-homogeneities induced by millisecond laser annealing in advanced CMOS technologies
at die level. Because of the design, the device layout at the wafer surface introduces during this anneal significant spatial
variations of optical absorption and heat transfer that can induce temperature non-uniformities over the die, often called
‘pattern effects’. These temperature variations are becoming a major issue, since they are the origin of significant device
properties dispersion. A complete optical and thermal simulation set has been developed to estimate the temperature variations
induced by the topologies at the wafer surface during the laser anneal process. The modelling has been validated by either
a comparison with another software or reflectometry and electrical measurements on real structures. This work demonstrates
that the temperature variations are caused either by optical coupling or by thermal properties dispersion present at the wafer
surface at the anneal step. Finally, we demonstrate that the impact of the thin-film interferences and diffraction phenomena
is the critical issue for these pattern effects. 相似文献