Binding potential (BPND) is a commonly used PET outcome measure because it can be estimated without blood sampling if a brain reference region (RR) devoid of the target of interest exists. For many radioligands howeve...
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Binding potential (BPND) is a commonly used PET outcome measure because it can be estimated without blood sampling if a brain reference region (RR) devoid of the target of interest exists. For many radioligands however no RR exists and the total distribution volume (V-T) whose estimation requires arterial blood sampling is normally considered as the outcome measure. Here we present a method that allows calculation of BPND without requiring either blood samples or a RR. The method extends our previous algorithm for estimating non-displaceable distribution volumes (V-ND) without using a RR. Here we show that if a template input function with arbitrary amplitude but a shape similar to the actual arterial input function is used in the algorithm estimation of V-T and V-ND are both proportionally biased and thus this bias cancels out in the estimation of BPND. The method is evaluated using simulated data human data acquired with the serotonin 1A receptor radioligand [C-11]WAY-100635 and blocking data acquired in baboons using the serotonin 1A receptor radioligand [C-11]CUMI-101. We evaluated two versions of template input functions: an arbitrarily downscaled version of the actual arterial input function and an unsealed population-based input function. In addition we evaluated how shape modifications of the template input function impact the estimates of BPND. With the downscaled input function BPND values close to the gold standard were obtained. When the unsealed population-based based input function was used greater variability was observed but no discernable bias was introduced. When the input function shape was modified a systematic but small bias in BPND was introduced. We conclude that provided the shape of the arterial input function is adequately described determination of its amplitude is not necessary for estimation of BPND.
Motivation: Reconstruction of ancestral sequence histories, and estimation of parameters like indel rates, are improved by using explicit evolutionary models and summing over uncertain alignments. The previous best to...
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Motivation: Reconstruction of ancestral sequence histories, and estimation of parameters like indel rates, are improved by using explicit evolutionary models and summing over uncertain alignments. The previous best tool for this purpose (according to simulation benchmarks) was ProtPal, but this tool was too slow for practical use. Results: Historian combines an efficient reimplementation of the ProtPal algorithm with performance-improving heuristics from other alignment tools. Simulation results on fidelity of rate estimation via ancestral reconstruction, along with evaluations on the structurally informed alignment dataset BAliBase 3.0, recommend Historian over other alignment tools for evolutionary applications.
Algorithm of the 3D analysis developed for solution of boundary problem by combined method based on incorporating the FEM and Somigliana's integral formula is considered. The algorithm is modified for the case of ...
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Algorithm of the 3D analysis developed for solution of boundary problem by combined method based on incorporating the FEM and Somigliana's integral formula is considered. The algorithm is modified for the case of inhomogeneous medium. Efficiency of software implementations of both algorithms has been tested.
A new method for the removal of physiological artifacts in the experimental signals of human electroencephalograms (EEGs) has been developed. The method is based on decomposition of the signal in terms of empirical mo...
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A new method for the removal of physiological artifacts in the experimental signals of human electroencephalograms (EEGs) has been developed. The method is based on decomposition of the signal in terms of empirical modes. The algorithm involves EEG signal decomposition in terms of empirical modes, searching for modes with artifacts, removing these modes, and restoration of the EEG signal. The method was tested on experimental data and showed high efficiency in the removal of various physiological artifacts in EEGs.
A system and algorithm for controlling a complex flexible rotor on active magnenic bearings have been proposed that make it possible to significantly reduce the amplitude of rotor vibrations at critical frequencies. T...
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A system and algorithm for controlling a complex flexible rotor on active magnenic bearings have been proposed that make it possible to significantly reduce the amplitude of rotor vibrations at critical frequencies. The algorithm combines the identification of the forces of inertia caused by the residual imbalance and the formation of control actions compensating these forces. The effectiveness of the synthesized control system and control algorithm has been illustrated by computer simulation.
Similarity search-for example, identifying similar images in a database or similar documents on the web-is a fundamental computing problem faced by large-scale information retrieval systems. We discovered that the fru...
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Similarity search-for example, identifying similar images in a database or similar documents on the web-is a fundamental computing problem faced by large-scale information retrieval systems. We discovered that the fruit fly olfactory circuit solves this problem with a variant of a computer science algorithm (called locality-sensitive hashing). The fly circuit assigns similar neural activity patterns to similar odors, so that behaviors learned from one odor can be applied when a similar odor is experienced. The fly algorithm, however, uses three computational strategies that depart from traditional approaches. These strategies can be translated to improve the performance of computational similarity searches. This perspective helps illuminate the logic supporting an important sensory function and provides a conceptually new algorithm for solving a fundamental computational problem.
Based on the assumption that every node in the graph can be optimally reconstructed by a linear combination of its neighbor nodes, the undirected weight graph is constructed instead of Gaussian-based pairwise weightin...
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Based on the assumption that every node in the graph can be optimally reconstructed by a linear combination of its neighbor nodes, the undirected weight graph is constructed instead of Gaussian-based pairwise weighting, which improves the detection performance in cluttered background. Since the salient region can be directly and efficiently applied to a wide range of computer vision fields, for example, image classification and object recognition, it can be seen as a preprocessing step for further applications. Y. Tang et al. establish two dictionaries (i.e., background and union) for pixel representation to improve the performance of hyperspectral image classification in their article titled as "Sparse Representation Based Binary Hypothesis Model for Hyperspectral Image Classification."
The Constrained Application Protocol (CoAP) is specifically designed for constrained IoT devices and is being rapidly deployed for the communication needs of the IoT devices. CoAP has been specified with its own conge...
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ISBN:
(纸本)9781538663592;9781538663585
The Constrained Application Protocol (CoAP) is specifically designed for constrained IoT devices and is being rapidly deployed for the communication needs of the IoT devices. CoAP has been specified with its own congestion control algorithms because it runs on top of UDP that does not include any congestion control measures. These algorithms aim at taking into account the specific needs of the IoT communication. The need of running CoAP also over TCP has arised recently and is expected to be increasingly deployed alongside with CoAP over UDP. To understand the benefits and shortcomings of both CoAP over TCP and CoAP over UDP, we run an extensive set of experiments in different network settings and compare the performance of CoAP over TCP to the existing congestion control algorithms for CoAP over UDP. Our results reveal that even though CoAP over TCP has its known limitations it scales well and performs even better than expected in certain wireless settings that CoAP over UDP algorithms are specifically designed for, often even outperforming CoAP over UDP.
In order to realize intelligent control of mushroom planting's parameters of air temperature and humidity, lighting intensity, and temperature and humidity of soil culture materials, it carries out design with Zig...
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ISBN:
(纸本)9781538653746
In order to realize intelligent control of mushroom planting's parameters of air temperature and humidity, lighting intensity, and temperature and humidity of soil culture materials, it carries out design with ZigBee network, and intelligent fuzzy control algorithm as core. With advantages of high precision and stability, the design of sensor circuit mainly employs digital module sensors. The closed loop control is realized by employing fuzzy control algorithm and the test result shows that the deviation of air temperature is controlled within ±0.8°C, the deviation of air humidity is controlled within ±9%, the deviation of lighting intensity is controlled within ±21 LUX, the deviation of temperature of soil culture materials is controlled within ±0.9°C, and that of humidity of soil culture materials is controlled within ±6%, thus all parameters fully meet practical requirements of mushroom planting greenhouse.
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