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Different studies have demonstrated the importance of comorbidities to better understand the origin and evolution of medical complications. This study focuses on improvement of the predictive model interpretability based on simple logical features representing comorbidities. We use group lasso based feature interaction discovery followed by a post-processing step, where simple logic terms are added. In the final step, we reduce the feature set by applying lasso logistic regression to obtain a compact set of non-zero coefficients that represent a more comprehensible predictive model. The effectiveness of the proposed approach was demonstrated on a pediatric hospital discharge dataset that was used to build a readmission risk estimation model. The evaluation of the proposed method demonstrates a reduction of the initial set of features in a regression model by 72%, with a slight improvement in the Area Under the ROC Curve metric from 0.763 (95% CI: 0.755–0.771) to 0.769 (95% CI: 0.761–0.777). Additionally, our results show improvement in comprehensibility of the final predictive model using simple comorbidity based terms for logistic regression.  相似文献   
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The first direct evidence for specific metal-binding sites in pure human and pure rabbit sex steroid-binding protein (SBP) is obtained using the luminescent lanthanide terbium. Terbium, a probe for calcium sites in proteins, provided protection of the SBP steroid-binding activity in diluted human serum samples equivalent to that provided by calcium. Pure SBP, first treated with ethylenediaminetetraacetate, was dialyzed against buffer containing TbCl3. After gel filtration to remove nonspecifically bound terbium, the protein was denatured in urea. The amount of protein-bound terbium was determined by luminescence enhancement of the lanthanide using the chelator dipicolinate, yielding four metal-binding sites per mole of dimer protein from both species.  相似文献   
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While magnetoreception in birds has been studied intensively, the literature on magnetoreception in bony fish, and particularly in non-migratory fish, is quite scarce. We examined alignment of common carps (Cyprinus carpio) at traditional Christmas sale in the Czech Republic. The sample comprised measurements of the directional bearings in 14,537 individual fish, distributed among 80 large circular plastic tubs, at 25 localities in the Czech Republic, during 817 sampling sessions, on seven subsequent days in December 2011. We found that carps displayed a statistically highly significant spontaneous preference to align their bodies along the North-South axis. In the absence of any other common orientation cues which could explain this directional preference, we attribute the alignment of the fish to the geomagnetic field lines. It is apparent that the display of magnetic alignment is a simple experimental paradigm of great heuristic potential.  相似文献   
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Two large, electron dense heavy-metal complexes were found to bind to crystals of heavy riboflavin synthase. The crystallographic analysis by difference Fourier methods shows that the tungsten cluster compound [(W3O2(O2CCH3)6]2+, which has trigonal symmetry, binds to a site on the 3-fold axis of the protein. The heteropolytungstate compound [NaP5W30O110]14-, which has pentagonal symmetry, binds to a site on the 5-fold axis of the protein.  相似文献   
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Background  

All human pathogenic Yersinia species share a virulence-associated type III secretion system that translocates Yersinia effector proteins into host cells to counteract infection-induced signaling responses and prevent phagocytosis. Dictyostelium discoideum has been recently used to study the effects of bacterial virulence factors produced by internalized pathogens. In this study we explored the potential of Dictyostelium as model organism for analyzing the effects of ectopically expressed Yersinia outer proteins (Yops).  相似文献   
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Five potent, lipophilic beta-adrenoceptor antagonists (carvedilol, pindolol, toliprolol and fluorinated analogs of bupranolol and penbutolol) were labeled with either carbon-11 or fluorine-18 and evaluated for cerebral beta-adrenoceptor imaging in experimental animals. The standard radioligand for autoradiography of beta-adrenoceptors, [125I]-iodocyanopindolol, was also included in this survey. All compounds showed either very low uptake in rat brain or a regional distribution that was not related to beta-adrenoceptors, whereas some ligands did display specific binding in heart and lungs. Apparently, the criteria of a high affinity and a moderately high lipophilicity were insufficient to predict the suitability of beta-adrenergic antagonists for visualization of beta-adrenoceptors in the central nervous system.  相似文献   
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