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951.
Krizkova S Ryvolova M Hynek D Eckschlager T Hodek P Masarik M Adam V Kizek R 《Electrophoresis》2012,33(12):1824-1832
Zinc(II) as the only transition metal lacking redox activity is an essential part of approximately 10% proteins as a cofactor of these proteins. Considering the fact that there are numerous zinc(II) containing proteins, proteomics and metallomics studies aimed on them require accurate methods for preparation of real biological samples prior to their subsequent analysis using 2DE and MS. For this purpose, we suggested a new method based on chicken anti-zinc antibodies and magnetizable particles. Antibodies were covalently immobilized to the surface of paramagnetic beads activated with tosyl group. Binding of the antibody to the beads was confirmed by secondary anti-chicken antibody conjugated with horseradish peroxidase. The immunoextraction conditions, such as concentration of the beads (6-18 μg/mL of the sample), time of immunoextraction (6-34 min), pH and composition of the elution buffer, and time of extraction (48-300 s) were optimized. Subsequently, zinc proteins were extracted from human plasma and total concentration of zinc was monitored by electrochemical detection in the extracts. Under optimal conditions it was possible to monitor the proteins and zinc removal from the sample by chip CE, SDS-PAGE, and indirectly using electrochemistry. 相似文献
952.
953.
Adam Janiak Wladyslaw Janiak Mikhail Y. Kovalyov Frank Werner 《4OR: A Quarterly Journal of Operations Research》2012,10(4):347-360
We study problems of scheduling n unit-time jobs on m identical parallel machines, in which a common due window has to be assigned to all jobs. If a job is completed within the due window, then no scheduling cost incurs. Otherwise, a job-dependent earliness or tardiness cost incurs. The job completion times, the due window location and the size are integer valued decision variables. The objective is to find a job schedule as well as the location and the size of the due window such that a weighted sum or maximum of costs associated with job earliness, job tardiness and due window location and size is minimized. We establish properties of optimal solutions of these min-sum and min-max problems and reduce them to min-sum (traditional) or min-max (bottleneck) assignment problems solvable in O(n 5/m 2) and O(n 4.5log0.5 n/m 2) time, respectively. More efficient solution procedures are given for the case in which the due window size cost does not exceed the due window start time cost, the single machine case, the case of proportional earliness and tardiness costs and the case of equal earliness and tardiness costs. 相似文献
954.
Acoustic classification of multiple simultaneous bird species: a multi-instance multi-label approach 总被引:1,自引:0,他引:1
Briggs F Lakshminarayanan B Neal L Fern XZ Raich R Hadley SJ Hadley AS Betts MG 《The Journal of the Acoustical Society of America》2012,131(6):4640-4650
Although field-collected recordings typically contain multiple simultaneously vocalizing birds of different species, acoustic species classification in this setting has received little study so far. This work formulates the problem of classifying the set of species present in an audio recording using the multi-instance multi-label (MIML) framework for machine learning, and proposes a MIML bag generator for audio, i.e., an algorithm which transforms an input audio signal into a bag-of-instances representation suitable for use with MIML classifiers. The proposed representation uses a 2D time-frequency segmentation of the audio signal, which can separate bird sounds that overlap in time. Experiments using audio data containing 13 species collected with unattended omnidirectional microphones in the H. J. Andrews Experimental Forest demonstrate that the proposed methods achieve high accuracy (96.1% true positives/negatives). Automated detection of bird species occurrence using MIML has many potential applications, particularly in long-term monitoring of remote sites, species distribution modeling, and conservation planning. 相似文献
955.
A new orthogonal-plane cinema-stereoscopic particle image velocimetry (OPCS-PIV) diagnostic has been used to measure the dynamics
of three-dimensional turbulence–flame interactions. The diagnostic employed two orthogonal PIV planes, with one aligned perpendicular
and one aligned parallel to the streamwise flow direction. In the plane normal to the flow, temporally resolved slices of
the nine-component velocity gradient tensor were determined using Taylor’s hypothesis. Volumetric reconstruction of the 3D
turbulence was performed using these slices. The PIV plane parallel to the streamwise flow direction was then used to measure
the evolution of the turbulence; the path and strength of 3D turbulent structures as they interacted with the flame were determined
from their image in this second plane. Structures of both vorticity and strain-rate magnitude were extracted from the flow.
The geometry of these structures agreed well with predictions from direct numerical simulations. The interaction of turbulent
structures with the flame also was observed. In three dimensions, these interactions had complex geometries that could not
be reflected in either planar measurements or simple flame–vortex configurations. 相似文献
956.
The purpose of this investigation is to evaluate the positioning and to confirm the volume concept of the Lea's Shield diaphragm utilizing MR imaging. We evaluated the device in two women, one nulliparous and one multiparous. We were able to comprehensively evaluate the device in both patients and answer all questions regarding anatomical positioning and aspects pertaining to the morphology of the device relevant to its function. MRI may be effectively utilized to evaluate contraceptive devices and their relationship to adjacent anatomical structures. This may enhance the gynecologist's clinical assessment of its correct positioning and efficacy. 相似文献
957.
We consider second-order, strongly elliptic, operators with complex coefficients in divergence form on . We assume that the coefficients are all periodic with a common period. If the coefficients are continuous we derive Gaussian
bounds, with the correct small and large time asymptotic behaviour, on the heat kernel and all its H?lder derivatives. Moreover,
we show that the first-order Riesz transforms are bounded on the -spaces with . Secondly if the coefficients are H?lder continuous we prove that the first-order derivatives of the kernel satisfy good
Gaussian bounds. Then we establish that the second-order derivatives exist and satisfy good bounds if, and only if, the coefficients
are divergence-free or if, and only if, the second-order Riesz transforms are bounded. Finally if the third-order derivatives
exist with good bounds then the coefficients must be constant.
Received in final form: 28 February 2000 / Published online: 17 May 2001 相似文献
958.
N. P. Boley Paul De Bièvre Philip D. P. Taylor Adam Uldall 《Accreditation and quality assurance》2001,6(6):244-251
Many laboratories take part in proficiency testing schemes, external quality assessment programmes and other interlaboratory
comparisons. These have many similarities but also important differences in their modus operandi and evaluation of performance of participating laboratories. This paper attempts to highlight both the similarities and differences. It also puts particular emphasis on requirements
called ”target values for uncertainty” and their meaning.
Received: 24 January 2001 Accepted: 25 January 2001 相似文献
959.
Adam Khatir Sam M. M. O. Ahamed F. El Khangi P. Roos 《Journal of Radioanalytical and Nuclear Chemistry》2000,245(2):411-414
This paper presents the activity concentrations of Pu isotopes in surface marine sediments collected from the Sudanese coast of the Red Sea. The following concentration ranges were determined: 238Pu, 4.7–28.6 mBq/kg; 239+240Pu, 53–343 mBq/kg dry weight. The average activity ratios of 238Pu/239+240Pu (0.075±0.045 mBqk/kg) and 239+240Pu/137Cs (0.026±0.025 mBq/kg) are appropriately comparable to the literature values that are characteristic of the global fallout from the atmospheric nuclear weapon tests. However, 239+240Pu/137Cs ratio in sediments collected from the biologically rich fringing reef is an order of magnitude higher compared to other sampling locations. 相似文献
960.
We study the following tiling problem in d dimensions: given a d-dimensional rectangular array of nonnegative numbers and an integer p, partition the array into at most p rectangular subarrays so that the maximum weight of any subarray is minimized; the weight of a subarray is the sum of its elements. The rectangular tiling problem is motivated by applications in data mining, data partitioning, and video compression. Recently, Khanna, Muthukrishnan, and Paterson [SODA '98], showed that the tiling problem is NP-complete and gave a 2.5-approximation algorithm for d = 2.In this paper, we extend their result to multidimensional arrays and give an algorithm with approximation ratio
, for d ≥ 2. The algorithm can be implemented to run in worst-case time O(N + p log N) time, where N is the size of the array, and the constant is of the order d!. We also obtain a similar algorithm for the dual tiling problem, where the goal is to compute a tiling of weight at most W using as few tiles as possible. Our algorithm yields an approximation factor (2d + 1).We implemented our algorithm and ran simulation tests on multidimensional arrays with random data. In our limited experiments, the algorithm always produced approximations that were no worse than factor two from the optimal. 相似文献