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31.
We propose an algorithm for adaptive efficient acquisition of fluorescence microscopy data sets using a multirate (MR) approach. We simulate acquisition as part of a larger system for protein classification based on their subcellular location patterns and, thus, strive to maintain the achieved level of classification accuracy as much as possible. This problem is similar to image compression but unique due to additional restrictions, namely causality; we have access only to the information scanned up to that point. While we do want to acquire fewer samples with as low distortion as possible to achieve compression, our goal is to do so while affecting the overall classification accuracy as little as possible. We achieve this by using an adaptive MR scanning scheme which samples the regions of the image area that hold the most pertinent information. Our results show that we can achieve significant compression which we can then use to aquire faster or to increase space resolution of our data set, all while minimally affecting the classification accuracy of the entire system.  相似文献   
32.
The impact of MAC parameters on the performance of 802.15.4 PAN   总被引:1,自引:0,他引:1  
The operation of a personal area network, operating under the IEEE Standard 802.15.4 in the beacon enabled mode, is analyzed using the theory of discrete time Markov chains and M/G/1/K queues. The model includes the impact of different parameters such as packet arrival rate, number of stations, station’s buffer size, packet size, and inactive period between the beacons. We have derived several important performance parameters such as probability of access, probability that medium is idle, queue length distribution in the device, and probability distribution of the packet service time. Some important conclusions regarding the implementation of 802.15.4 networks and compatible network devices are outlined.  相似文献   
33.
Type 2 diabetes (T2D), one of the most prevalent noncommunicable diseases, is often preceded by insulin resistance (IR), which underlies the inability of tissues to respond to insulin and leads to disturbed metabolic homeostasis. Mitochondria, as a central player in the cellular energy metabolism, are involved in the mechanisms of IR and T2D. Mitochondrial function is affected by insulin resistance in different tissues, among which skeletal muscle and liver have the highest impact on whole-body glucose homeostasis. This review focuses on human studies that assess mitochondrial function in liver, muscle and blood cells in the context of T2D. Furthermore, different interventions targeting mitochondria in IR and T2D are listed, with a selection of studies using respirometry as a measure of mitochondrial function, for better data comparison. Altogether, mitochondrial respiratory capacity appears to be a metabolic indicator since it decreases as the disease progresses but increases after lifestyle (exercise) and pharmacological interventions, together with the improvement in metabolic health. Finally, novel therapeutics developed to target mitochondria have potential for a more integrative therapeutic approach, treating both causative and secondary defects of diabetes.  相似文献   
34.
How can training programs foster counseling and clinical psychologists' scholarly productivity? This study examined the impact of academic and internship research training environments (RTEs) on the scholarly activity of 223 early career professionals. Results supported the construct validity of the Internship Research Training Environment scale through cross-validation and confirmatory factor analysis. Findings revealed differences in perceptions of the internship RTE and scholarly productivity as a function of academic training philosophy and internship training philosophy. Finally, results suggested that academic and internship RTEs could influence research interest and scholarly productivity indirectly by enhancing research self-efficacy and research outcome expectations. (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   
35.
Bone scaffolds provide a structural support for tissue development. Existing bone scaffolds are mainly characterized by complex porous designs whose shortcomings are a low level of permeability for growing tissue, and a difficult design customization. Scaffolds with nucleuses (rods or lattices) as basic elements should improve bone regeneration and enable higher design flexibility. In this paper, we present two new methods for building 3D geometrical models of personalized scaffolds, which are based on method of anatomical features. Methods are demonstrated in the case of scaffold for the mandible bone. This approach greatly reduces the designer effort and time, while enabling easy personalization of scaffolds’ shape and geometry.  相似文献   
36.
37.
Acenaphthylene, fluoranthene and their congeners are compounds that, in view of their chemical and physical properties, belong among benzenoid hydrocarbons. However, because of the presence of a five-membered ring, in all chemical-graph-theoretical considerations of benzenoid systems, these species have been disregarded. Continuing our recent studies of the title compounds, we report here on a peculiar characteristic of the pattern of their cyclic conjugation, named “the phenyl-cyclopentadienyl rule” (PCP rule): if a benzene ring is connected with the (unique) five-membered ring by exactly one carbon-carbon bond (which we refer to as a PCP constellation), then the cyclic conjugation in the five-membered ring significantly increases. If there are several PCP constellations, then the intensity of cyclic conjugation is additionally increased.  相似文献   
38.
Abstract

In this study, we present the development of an innovative dry powder dexamethasone (Dex) nasal delivery system comprising Dex-loaded lipid/alginate nanoparticles incorporated within pectin microspheres (Dex/NPs-loaded pectin microspheres; DNM). DNM microspheres were characterized by the mean diameter of 2.76?±?0.10?µm, zeta-potential of –36.2?±?1.1?mV, and drug loading of 3.3?±?0.3%. The morphology study revealed irregular microsphere surface forming external voids. In contact with simulated nasal fluid, DNM microspheres demonstrated desirable property of moderate swelling and ensured stronger mucoadhesion compared with conventional Dex-loaded pectin microspheres. The strategy of Dex incorporation within the lipid/alginate NPs resulted in prolonged Dex release in relation to Dex being directly entrapped within the conventional pectin microspheres. DNM microspheres showed excellent biocompatibility and rendered Dex permeation across the selected epithelial cell model similar to that of Dex solution. In conclusion, balanced biopharmaceutical properties of the proposed nasal Dex delivery system provides the potential for prolonged contact time with nasal mucosa, prolonged therapeutic effect, and improved patient compliance.  相似文献   
39.
The Autonomous Province of Vojvodina is an autonomous province in the Republic of Serbia. It is located in the northern part of the country, in the Pannonia plain. Vojvodina is an energy-deficient province. The average yearly quantity of the cellulose wastes in Vojvodina amounts to about 9 millions tons barely in the agriculture, and the same potential on the level of Serbia is estimated to almost 13 million tons. Only minor part of straw is utilized, and almost two-thirds are incinerated on fields owing to the problems during plowing under. The large sector in Serbia utilizes only about 15% of straw, while the individual one utilizes about 50% of straw and 20% of cornstalks. Environment pollutions, abandonment of the utilization of at least of one-third of the yield and extermination of the natural resources, primarily of humus, represent very adverse results of such procedures. Main problems with respect to the profitable usage of straw and other post-harvest residues are high expenses of their collection (collecting, balling or some other manner of compression), transportation from production- to the usage cites, as well as their handling and storaging. The agricultural production in Serbia should be based on the system of farms. For the efficient farming, it is obvious to organize life of producer and of his family immediately close to the production capacities. For the agriculture development, it is obvious to create a system of premiums, efficient crediting and the elaborated tax system that could create a basis for the certitude of work, confidence and constant growth of production, together with the mentioned and other measures. As the result of the activities oriented to substitution of the classical energents with energy obtained from biomass, farm that is in a higher degree energetically independent should be created. In such case, farms should apply the basic principles of the cleaner manufacturing, as an integral part of the concept of the sustainable development.  相似文献   
40.
Whereas some applications require correct computation many others do not. A large domain where perfect functional performance is not always required is multimedia and DSP systems. Relaxing the requirement of 100% correctness for devices and interconnections may dramatically reduce costs of manufacturing, verification, and testing. The goal of this paper is to develop a method for trading computational correctness for an additional chip area involved by fault-tolerance implementation. The method is demonstrated for the BP array in the following way: only the most significant bits of the output word are made fault-tolerant. By introducing the concept of partially error-tolerant BP array, designers achieve one more degree of tradeoff freedom. Formal definitions of the proposed terms are given. A mathematical path based on transitive closure that generates an error significance map for the BP array is proposed. The design tradeoff is demonstrated through FPGA implementation. The achieved area savings are presented as a function of a number of most significant fault-tolerant bits.  相似文献   
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