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61.
Pei-Chann Chang Jyun-Jie Lin Jui-Chien Hsieh Julia Weng 《Applied Soft Computing》2012,12(10):3165-3175
This study presented a new diagnosis system for myocardial infarction classification by converting multi-lead ECG data into a density model for increasing accuracy and flexibility of diseases detection. In contrast to the traditional approaches, a hybrid system with HMMs and GMMs was employed for data classification. A hybrid approach using multi-leads, i.e., lead-V1, V2, V3 and V4 for myocardial infarction were developed and HMMs were used not only to find the ECG segmentations but also to calculate the log-likelihood value which was treated as statistical feature data of each heartbeat's ECG complex. The 4-dimension feature vector extracted by HMMs was clustered by GMMs with different numbers of distribution (disease and normal data). SVMs classifier was also examined for comparison with our system in experimental result. There were total 1129 samples of heartbeats from clinical data, including 582 data with myocardial infarction and 547 normal data. The sensitivity of this diagnosis system achieved 85.71%, specificity achieved 79.82% and accuracy achieved 82.50% statistically. 相似文献
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Tiffany D. Andras Troy S. Alexander Asiri Gahlena R. Mitchell Parry Facundo M. Fernandez Julia Kubanek May D. Wang Mark E. Hay 《Journal of chemical ecology》2012,38(10):1203-1214
Coral reefs are in global decline, with seaweeds increasing as corals decrease. Although seaweeds inhibit coral growth, recruitment, and survivorship, the mechanism of these interactions is poorly understood. Here, we used field experiments to show that contact with four common seaweeds induces bleaching on natural colonies of Porites rus. Controls in contact with inert, plastic mimics of seaweeds did not bleach, suggesting seaweed effects resulted from allelopathy rather than shading, abrasion, or physical contact. Bioassay-guided fractionation of the hydrophobic extract from the red alga Phacelocarpus neurymenioides revealed a previously characterized antibacterial metabolite, neurymenolide A, as the main allelopathic agent. For allelopathy of lipid-soluble metabolites to be effective, the compounds would need to be deployed on algal surfaces where they could transfer to corals on contact. We used desorption electrospray ionization mass spectrometry (DESI-MS) to visualize and quantify neurymenolide A on the surface of P. neurymenioides, and we found the molecule on all surfaces analyzed, with highest concentrations on basal portions of blades. 相似文献
64.
Online social networks became a global phenomenon with enormous social as well as economic impact within a few years. Alone, the most popular online social network, Facebook, counts currently more than 850 million users worldwide. Consequently, online social networks attract a great deal of attention among practitioners as well as researchers. The goal of this article is to provide an overview of online social networks in order to contribute to a better understanding of this worldwide phenomenon. In this context, we address for example the following questions: What are the major functionalities and characteristics of online social networks? What are the users’ motives for using them and how did online social networks emerge and develop over time? What is the impact and value of online social networks from a business perspective and what are corresponding challenges and risks? 相似文献
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Developing solar power generating resources on dormant, suspect property is an evolving activity, growing in popularity. 相似文献
68.
Yichi Zhang Julia Glaum Matthias C. Ehmke Keith J. Bowman John E. Blendell Mark J. Hoffman 《Journal of the American Ceramic Society》2016,99(4):1287-1293
(Ba,Ca)(Ti,Zr)O3 lead‐free piezoelectric ceramics have been considered to be one of the most potential lead‐free alternatives for PZT in the room‐temperature range. The stability of the piezoelectric performance during unipolar cycling is investigated in this study. It is found that the unipolar fatigue behavior is similar to soft PZT. Developments of bias field, offset polarization, asymmetry in strain, and dielectric hysteresis loops are observed during bipolar measurements. The changes are mainly contributed to the migration of charge carriers to the grain boundaries driven by the unscreened depolarization field. Redistribution of the accumulated charge carriers by bipolar electric cycling or thermal annealing can significantly recover the unipolar fatigued state. The unipolar strain response stabilized after 1000 cycles at 0.053% for an electric field of 0.6 kV/mm (d33*= 883 pm/V), which is a good characteristic for actuator applications. 相似文献
69.
Synthesis and Biopharmaceutical Evaluation of Imatinib Analogues Featuring Unusual Structural Motifs 下载免费PDF全文
Prof. Kyriacos C. Nicolaou Dr. Dionisios Vourloumis Dr. Sotirios Totokotsopoulos Dr. Athanasios Papakyriakou Dr. Holger Karsunky Hanan Fernando Dr. Julia Gavrilyuk Dr. Damien Webb Dr. Antonia F. Stepan 《ChemMedChem》2016,11(1):31-37
A convenient synthesis of imatinib, a potent inhibitor of ABL1 kinase and widely prescribed drug for the treatment of a variety of leukemias, was devised and applied to the construction of a series of novel imatinib analogues featuring a number of non‐aromatic structural motifs in place of the parent molecule's phenyl moiety. These analogues were subsequently evaluated for their biopharmaceutical properties (e.g., ABL1 kinase inhibitory activity, cytotoxicity). The bicyclo[1.1.1]pentane‐ and cubane‐containing analogues were found to possess higher themodynamic solubility, whereas cubane‐ and cyclohexyl‐containing analogues exhibited the highest inhibitory activity against ABL1 kinase and the most potent cytotoxicity values against cancer cell lines K562 and SUP‐B15. Molecular modeling was employed to rationalize the weak activity of the compounds against ABL1 kinase, and it is likely that the observed cytotoxicity of these agents arises through off‐target effects. 相似文献
70.
Bin Qiu Susan E. Luczak Tamara L. Wall Aaron M. Kirchhoff Yuxue Xu Mimy Y. Eng Robert B. Stewart Weinian Shou Stephen L. Boehm II Julia A. Chester Weidong Yong Tiebing Liang 《International journal of molecular sciences》2016,17(8)
FKBP5 encodes FK506-binding protein 5, a glucocorticoid receptor (GR)-binding protein implicated in various psychiatric disorders and alcohol withdrawal severity. The purpose of this study is to characterize alcohol preference and related phenotypes in Fkbp5 knockout (KO) mice and to examine the role of FKBP5 in human alcohol consumption. The following experiments were performed to characterize Fkpb5 KO mice. (1) Fkbp5 KO and wild-type (WT) EtOH consumption was tested using a two-bottle choice paradigm; (2) The EtOH elimination rate was measured after intraperitoneal (IP) injection of 2.0 g/kg EtOH; (3) Blood alcohol concentration (BAC) was measured after 3 h limited access of alcohol; (4) Brain region expression of Fkbp5 was identified using LacZ staining; (5) Baseline corticosterone (CORT) was assessed. Additionally, two SNPs, rs1360780 (C/T) and rs3800373 (T/G), were selected to study the association of FKBP5 with alcohol consumption in humans. Participants were college students (n = 1162) from 21–26 years of age with Chinese, Korean or Caucasian ethnicity. The results, compared to WT mice, for KO mice exhibited an increase in alcohol consumption that was not due to differences in taste sensitivity or alcohol metabolism. Higher BAC was found in KO mice after 3 h of EtOH access. Fkbp5 was highly expressed in brain regions involved in the regulation of the stress response, such as the hippocampus, amygdala, dorsal raphe and locus coeruleus. Both genotypes exhibited similar basal levels of plasma corticosterone (CORT). Finally, single nucleotide polymorphisms (SNPs) in FKBP5 were found to be associated with alcohol drinking in humans. These results suggest that the association between FKBP5 and alcohol consumption is conserved in both mice and humans. 相似文献