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1.
Although ischemic heart disease tends to cluster in families, previous studies have reported a modest (2-fold increased risk) to strong (10-fold increased risk) contribution of family history to the explanation of disease occurrence. The authors assessed the familial aggregation of early-onset myocardial infarction in 11,307 adults aged <65 years who participated in the Third National Health and Nutrition Examination Survey. Logistic regression was used to obtain odds ratios (ORs) and 95% confidence intervals (CIs). A parental history was more common in those with (n = 237) than in those without (n = 11,070) a myocardial infarction (19.8 vs. 7.9%, p < or = 0.01). Adults with a parental history were also more likely to have multiple risk factors for cardiovascular disease (OR for four or five risk factors compared with none: 2.9, 95% CI: 1.4, 6.3). After multivariate adjustment, the likelihood of myocardial infarction was more than three times greater among adults with a parental history than among those without (95% CI: 1.7, 6.7). A maternal history of myocardial infarction was strongly associated (OR = 6.1, 95% CI: 2.1, 17.4) with an increased likelihood of myocardial infarction, and a paternal history was associated with a 3-fold (95% CI: 1.5, 6.3) increased likelihood of myocardial infarction after adjustment for cardiovascular disease risk factors. These results suggest a familial aggregation of early-onset myocardial infarction and show that family history is strongly associated with cardiovascular disease risk factors.  相似文献   
2.
A special strain gage (PhotoStress® Separator Gage, Measurements Group, Inc., Raleigh, NC) designed to measure the sum (? 1 +? 2) of the principal strains, is used in conjunction with photoelastic-coating measurements (? 1 -? 2) to establish the value of each principal strain (? 1 and? 2). The summation strain signal is effectively independent of angular orientation (measurement direction), and by design, the gage negates soldering risks, self-heating, and localized-reinforcement considerations normally associated with strain-gage measurements on plastic parts.  相似文献   
3.
Conditions for similarity have been derived for phenomena involving an exploding wire, propagation of the resulting shock through a fluid, and inelastic deformation or fracture of a structure. This analysis considers the capacitance, voltage and material properties of the exploding wire, as well as the geometry and material properties of the fluid and structure. Model experiments involving large inelastic deformation of aluminum diaphragms agree well with the theoretical predictions. Comparison of deformations due to chemical explosives and exploding wires has been made in an effort to establish an ‘equivalence’ between chemical and electrical explosions. The purpose of this is to provide a basis for using small-scale experiments with exploding wires to predict the performance of larger systems using chemical explosives. The exploding wire appears to provide a precise loading for small-scale structural-model experiments and explosion-forming experiments.  相似文献   
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In this paper we introduce simplified, exact, combinatorial formulas that arise in the vortex interaction model found in [33]. These combinatorial formulas allow for the efficient implementation and development of a new multi-moment vortex method (MMVM) using a Hermite expansion to simulate 2D vorticity. The method naturally allows the particles to deform and become highly anisotropic as they evolve without the added cost of computing the non-local Biot–Savart integral. We present three examples using MMVM. We first focus our attention on the implementation of a single particle, large number of Hermite moments case, in the context of quadrupole perturbations of the Lamb–Oseen vortex. At smaller perturbation values, we show the method captures the shear diffusion mechanism and the rapid relaxation (on Re1/3 time scale) to an axisymmetric state. We then present two more examples of the full multi-moment vortex method and discuss the results in the context of classic vortex methods. We perform numerical tests of convergence of the single particle method and show that at least in simple cases the method exhibits the exponential convergence typical of spectral methods. Lastly, we numerically investigate the spatial accuracy improvement from the inclusion of higher Hermite moments in the full MMVM.  相似文献   
6.
In the classic blockmodel formulation, a social network among members of a population with n actors and k relations (types of tie) is arrayed as k n X n matrices. Though this is a three‐dimensional data structure, it is typically reduced to a two‐way analysis. In this paper, a three‐way procedure for analyzing multigraph data is developed. Specifically, in addition to applying the rule of structural equivalence to collapse actors, it is also applied to the relations (the third dimension), and structurally equivalent sets of relations are collapsed. The result is a three‐dimensional blockmodel (image) of social structure that is a more parsimonious representation of social structure than the classic two‐dimensional blockmodel images. The three‐dimensional approach is illustrated by application to three case studies: Homan's Bank Wiring Room, Sampson's monastery, and a local economy of hospital services. The structural equivalence approach to relations is further explored by applying it to the individual‐level Liking and Antagonism relations and their compounds (of length four or less) in the Bank Wiring Room. This application demonstrates that the structural equivalence approach can be used to identify equality equations for primitive and compound relations.  相似文献   
7.
We show how linear Weingarten surfaces appear as special Ω-surfaces and give a characterization of those linear Weingarten surfaces that allow a Weierstrass type representation.  相似文献   
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9.
A time-dependent density functional theory (TD-DFT) study was carried out on tautomers of the mycotoxin citrinin in the neutral, anionic, and cationic forms to gain insight into the role of chemical structure on detection. Steady-state fluorescence studies of citrinin in micellar aqueous solutions produced unusual results for ionic surfactants and the neutral Triton X-100 enhanced fluorescence emission. Ground-state and time-dependent density functional studies were carried out on five tautomers of citrinin using the B3LYP density functional and the 6-311+G(2df,2p) basis set. The investigation revealed that deprotonation is a major factor governing the shifts in fluorescence excitation and emission maxima. Moreover, the position of the lowest unoccupied molecular orbitals is removed from the fluorophore moiety of citrinin in the dianionic state which is consistent with the diminished fluorescence of the toxin in basic solutions. The ionic characteristics of certain chemosensors can influence the structure and intrinsic spectroscopic properties of citrinin.  相似文献   
10.
Certainly a highlight in the career of Nobel Laureate Professor Robert Burns Woodward (1917–1979) was the foundation of the Woodward Research Institute (WRI) at Ciba AG in Basel, Switzerland, in 1963. Woodward's remarkable accomplishments in the development of organic chemistry altered not only our concepts of molecular structure, but also our comprehension of physico‐chemical properties. In his legacy, Woodward devised innovative strategies for natural product syntheses based on brilliant rationale of their properties and an uncanny sense of Nature. The chemistry community benefited not only at Harvard but especially in Basel and Zürich from Woodward's inspiring lectures and the opportunity to learn from the chemistry Meister. This article highlights parts of the chemistry and some personalities that contributed to forefront investigations at the Woodward Research Institute which began at the former Novartis legacy company, Ciba AG, Basel.  相似文献   
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