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91.
Daniel S. Yeung Wing W. Y. Ng Aki P. F. Chan Patrick P. K. Chan Michael Firth Eric C. C. Tsang 《系统科学与系统工程学报(英文版)》2007,16(2):166-180
Company bankruptcies cost billions of dollars in losses to banks each year. Thus credit risk prediction is a critical part of a bank's loan approval decision process. Traditional financial models for credit risk prediction are no longer adequate for describing today's complex relationship between the financial health and potential bankruptcy of a company. In this work, a multiple classifier system (embedded in a multiple intelligent agent system) is proposed to predict the financial health of a company. In our model, each individual agent (classifier) makes a prediction on the likelihood of credit risk based on only partial information of the company. Each of the agents is an expert, but has limited knowledge (represented by features) about the company. The decisions of all agents are combined together to form a final credit risk prediction. Experiments show that our model out-performs other existing methods using the benchmarking Compustat American Corporations dataset. 相似文献
92.
93.
Superconductivity in CaCuO2 as a result of field-effect doping. 总被引:2,自引:0,他引:2
J H Sch?n M Dorget F C Beuran X Z Zu E Arushanov C Deville Cavellin M Lagu?s 《Nature》2001,414(6862):434-436
Understanding the doping mechanisms in the simplest superconducting copper oxide-the infinite-layer compound ACuO2 (where A is an alkaline earth metal)-is an excellent way of investigating the pairing mechanism in high-transition-temperature (high-Tc) superconductors more generally. Gate-induced modulation of the carrier concentration to obtain superconductivity is a powerful means of achieving such understanding: it minimizes the effects of potential scattering by impurities, and of structural modifications arising from chemical dopants. Here we report the transport properties of thin films of the infinite-layer compound CaCuO2 using field-effect doping. At high hole- and electron-doping levels, superconductivity is induced in the nominally insulating material. Maximum values of Tc of 89 K and 34 K are observed respectively for hole- and electron-type doping of around 0.15 charge carriers per CuO2. We can explore the whole doping diagram of the CuO2 plane while changing only a single electric parameter, the gate voltage. 相似文献
94.
Nicol��s F. Lori 《Foundations of Science》2011,16(4):311-314
During the refereeing procedure of Anthropomorphic Quantum Darwinism by Thomas Durt, it became apparent in the dialogue between him and me that the definition of information in Physics is something about which not all authors agreed. This text aims at describing the concepts associated to information that are accepted as the standard in the Physics world community. 相似文献
95.
Rasmussen SG DeVree BT Zou Y Kruse AC Chung KY Kobilka TS Thian FS Chae PS Pardon E Calinski D Mathiesen JM Shah ST Lyons JA Caffrey M Gellman SH Steyaert J Skiniotis G Weis WI Sunahara RK Kobilka BK 《Nature》2011,477(7366):549-555
G protein-coupled receptors (GPCRs) are responsible for the majority of cellular responses to hormones and neurotransmitters as well as the senses of sight, olfaction and taste. The paradigm of GPCR signalling is the activation of a heterotrimeric GTP binding protein (G protein) by an agonist-occupied receptor. The β(2) adrenergic receptor (β(2)AR) activation of Gs, the stimulatory G protein for adenylyl cyclase, has long been a model system for GPCR signalling. Here we present the crystal structure of the active state ternary complex composed of agonist-occupied monomeric β(2)AR and nucleotide-free Gs heterotrimer. The principal interactions between the β(2)AR and Gs involve the amino- and carboxy-terminal α-helices of Gs, with conformational changes propagating to the nucleotide-binding pocket. The largest conformational changes in the β(2)AR include a 14 ? outward movement at the cytoplasmic end of transmembrane segment 6 (TM6) and an α-helical extension of the cytoplasmic end of TM5. The most surprising observation is a major displacement of the α-helical domain of Gαs relative to the Ras-like GTPase domain. This crystal structure represents the first high-resolution view of transmembrane signalling by a GPCR. 相似文献
96.
We studied reproduction of three species of crocodilians, Paleosuchus trigonatus, Caiman crocodilus and Melanosuchus niger, in the Xingu River, near the Belo Monte hydroelectric dam. The periods of laying and hatching of eggs were estimated for each nest before (2013–2014) and after (2016–2017) the river was dammed and the reservoir was formed. Nesting of the three species occurred between August and December, but was largely asynchronous; nest construction peaked in September for P. trigonatus, October for M. niger and November for C. crocodilus. Reservoir filling had little effect on the laying period of any of the species. Nests of P. trigonatus and M. niger were always within 0–12 m of the bank, whereas nests of C. crocodilus, which nests later in the season when flooding is more likely, were up to 100 m from the nearest water body. There was no relationship between distance from water and the number of eggs in nests, suggesting that larger and presumably more experienced females do not lay at different distances from the bank in any of the species. 相似文献
97.
Jana Fischer Gunnar Kleinau Claudia Rutz Denise Zwanziger Noushafarin Khajavi Anne Müller Maren Rehders Klaudia Brix Catherine L. Worth Dagmar Führer Heiko Krude Burkhard Wiesner Ralf Schülein Heike Biebermann 《Cellular and molecular life sciences : CMLS》2018,75(12):2227-2239
G-protein-coupled receptors (GPCRs) can constitute complexes with non-GPCR integral membrane proteins, while such interaction has not been demonstrated at a single molecule level so far. We here investigated the potential interaction between the thyrotropin receptor (TSHR) and the monocarboxylate transporter 8 (MCT8), a member of the major facilitator superfamily (MFS), using fluorescence cross-correlation spectroscopy (FCCS). Both the proteins are expressed endogenously on the basolateral plasma membrane of the thyrocytes and are involved in stimulation of thyroid hormone production and release. Indeed, we demonstrate strong interaction between both the proteins which causes a suppressed activation of Gq/11 by TSH-stimulated TSHR. Thus, we provide not only evidence for a novel interaction between the TSHR and MCT8, but could also prove this interaction on a single molecule level. Moreover, this interaction forces biased signaling at the TSHR. These results are of general interest for both the GPCR and the MFS research fields. 相似文献
98.
Juliana L. Segadilha Priscila S. Nascimento Fábio M. Mauro Cristiana S. Serejo Taiara R. Ramos Irene A. Cardoso 《Journal of Natural History》2018,52(1-2):1-11
A total of 3109 crustaceans belonging to 50 taxa distributed in 42 families were found in 117 analysed stomachs of flying gurnard (Dactylopterus volitans). Samples were obtained in April 2008 by the R/V Gyre using a bottom trawl towed in 12 stations at 14–100 m depth on the continental shelf of the Campos Basin, Brazil. The carcinofauna was analysed and the order Calanoida (Copepoda) found to be the most important item in terms of relative abundance and frequency of occurrence, followed by the order Amphipoda (Peracarida), the infraorder Brachyura (Decapoda), the order Stomatopoda and the subclass Myodocopa (Ostracoda). In the order Calanoida, the species Pontellopsis cf. villosa (Pontellidae) represented 98.04% of total crustacean abundance. The diet of Dactylopterus volitans varied according to fish size, with higher diversity of Crustacea at smaller size classes, decreasing in larger fishes. A similar pattern regarding depth was obtained, with greater diversity of taxa in gurnard stomachs caught at shallower depths. Flying gurnard is considered a generalized carnivore of invertebrates, eating mobile macrobenthic organisms, such as crustaceans, and its diet varies with its life stage, without any specific group as its main food source. 相似文献
99.
Z. Campos F. Muniz A. L. J Desbiez W. E. Magnusson 《Journal of Natural History》2016,50(25-26):1543-1548
Nests of Schneider’s dwarf caiman, Paleosuchus trigonatus, were located in the forests around three streams that drain into the Xingu River, Brazilian Amazonia, in October 2014. Camera traps were installed at the edge of four nests to document predators and female parental care. At two nests, females unsuccessfully defended their nests against one or more giant armadillos, Priodontes maximus, and nine-banded armadillos, Dasypus novemcinctus. Both armadillo species responded to the attack by fleeing and returning on the opposite side of the nest by going around the tree under which the nest was located. Giant armadillos have never before been recorded consuming caiman eggs and their diet has been described as consisting mostly of ants and termites. Another species of armadillo, Cabassous unicinctus, was also registered digging into a nest and probably consuming eggs, though it is generally considered to be primarily insectivorous. A tayra (Eira barbara), lizard (Tupinambis teguixin) and coati (Nasua nasua) were also registered taking eggs from nests during the day, but we obtained no registers of nest defence by caimans during the day. The three nests were attacked after 60 days of incubation, when the eggs were well developed. 相似文献
100.
Epigenetic asymmetry of imprinted genes in plant gametes 总被引:12,自引:0,他引:12
Gutiérrez-Marcos JF Costa LM Dal Prà M Scholten S Kranz E Perez P Dickinson HG 《Nature genetics》2006,38(8):876-878
Plant imprinted genes show parent-of-origin expression in seed endosperm, but little is known about the nature of parental imprints in gametes before fertilization. We show here that single differentially methylated regions (DMRs) correlate with allele-specific expression of two maternally expressed genes in the seed and that one DMR is differentially methylated between gametes. Thus, plants seem to have developed similar strategies as mammals to epigenetically mark imprinted genes. 相似文献