166,166 research outputs found
G. Vernon Block
No full text"Pte G. Vernon Block VX150404 7th Battalion [11] Platoon "B" Coy 1939 - 1945. Dulcie Block (wife)".Private G. Vernon Block VX150404. 7th Battalion, [11] Platoon, "B" Company 1939 - 1945. Dulcie Block (wife)
On Pathos Semitotal and Total Block Graph of a Tree
No full textThe concept of pathos of a graph G was introduced by Harary [2], as a collection of minimum number of line disjoint open paths whose union is G. The path number of a graph G is the number of paths in pathos. A new concept of a graph valued functions called the semitotal and total block graph of a graph was introduced by Kulli
Modeling Building Block Interdependency
No full textThe Building-Block Hypothesis appeals to the notion of problem decomposition and the assembly of solutions from sub-solutions. Accordingly, there have been many varieties of GA test problems with a structure based on building-blocks. Many of these problems use deceptive fitness functions to model interdependency between the bits within a block. However, very few have any model of interdependency between building-blocks; those that do are not consistent in the type of interaction used intra-block and inter-block. This paper discusses the inadequacies of the various test problems in the literature and clarifies the concept of building-block interdependency. We formulate a principled model of hierarchical interdependency that can be applied through many levels in a consistent manner and introduce Hierarchical If-and-only-if (H-IFF) as a canonical example. We present some empirical results of GAs on H-IFF showing that if population diversity is maintained and linkage is tight then the GA is able to identify and manipulate building-blocks over many levels of assembly, as the Building-Block Hypothesis suggests
Congenital heart block associated with Sjögren syndrome: case report
No full textBackground: Congenital heart block is a rare complication of pregnancy associated with Sjögren Syndrome that may result in the death of the foetus or infant, or the need for pacing in the newborn or at a later stage.Case report: The case is presented of a 64-year-old patient with primary Sjögren Syndrome and a history of having given birth to two sons with congenital heart block, both of whom required pacing several years later.Conclusion: The literature relating to this association is discussed including the suggested mechanism, long-term outcome of mothers of children with congenital heart block and preventive treatment strategies
Als Ihro Magnificenz, der Wolgebohrne, Hochgelahrte und Hocherfahrne Herr, Herr Johann Gottlob Krüger, der Arzeneigelahrtheit und Weltweisheit Doctor ... den 3ten Jenner 1757. zum zweiten mahle den Academischen Zepter übernahmen wolten Denselben ihre Hochachtung bezeugen Seiner Magnificenz gehorsamste Diener und Zuhörer G. C. Beireis, a. Mühlhausen, d. A. G. B. J. C. Berg, a. Hamburg. d. A. G. B. G. D. Block, a. Osnabrück, d. G. G. B. [u.a.]
No full textA building-block Royal Road where crossover is provably essential
No full textOne of the most controversial yet enduring hypotheses about what genetic algorithms (GAs) are good for concerns the idea that GAs process building-blocks. More specifically, it has been suggested that crossover in GAs can assemble short low-order schemata of above average fitness (building blocks) to create higher-order higher-fitness schemata. However, there has been considerable difficulty in demonstrating this rigorously and intuitively. Here we provide a simple building-block function that a GA with two-point crossover can solve on average in polynomial time, whereas an asexual population or mutation hill-climber cannot
A survey of blockholders and corporate control
No full textThe author surveys the empirical literature on large-percentage shareholders in public corporations, focusing on four key issues: the prevalence of blockholders; the motivation for block ownership; the effect of blockholders on executive compensation, leverage, the incidence of takeovers, and a wide range of corporate decisions; and the effect of blockholders on firm value. A central finding of this study is that there is little reason for policymakers or small investors to fear large-percentage shareholders in general, especially when the blockholders are active in firm management.Stockholders ; Corporate governance
A simple two-module problem to exemplify building-block assembly under crossover
No full textTheoretically and empirically it is clear that a genetic algorithm with crossover will outperform a genetic algorithm without crossover in some fitness landscapes, and vice versa in other landscapes. Despite an extensive literature on the subject, and recent proofs of a principled distinction in the abilities of crossover and non-crossover algorithms for a particular theoretical landscape, building general intuitions about when and why crossover performs well when it does is a different matter. In particular, the proposal that crossover might enable the assembly of good building-blocks has been difficult to verify despite many attempts at idealized building-block landscapes. Here we show the first example of a two-module problem that shows a principled advantage for cross-over. This allows us to understand building-block assembly under crossover quite straightforwardly and build intuition about more general landscape classes favoring crossover or disfavoring it
Leaps: an approach to the block structure of a graph
No full textTo study the block structure of a connected graph G=(V,E), we introduce two algebraic approaches that reflect this structure: a binary operation + called a leap operation and a ternary relation L called a leap system, both on a finite, nonempty set V. These algebraic structures are easily studied by considering their underlying graphs, which turn out to be block graphs. Conversely, we define the operation +G as well as the set of leaps LG of the connected graph G. The underlying graph of +G , as well as that of LG , turns out to be just the block closure of G (i.e. the graph obtained by making each block of G into a complete subgraph).
Acquired heart block: A possible complication of patent ductus arteriosus in a preterm infant
No full textA large patent ductus arteriosus (PDA) is a frequently encountered clinical problem in extremely low birth weight (ELBW) infants. It leads to an increased pulmonary blood flow and in a decreased or reversed diastolic flow in the systemic circulation, resulting in complications. Here we report a possible complication of PDA not previously published. On day 8 of life, a male ELBW infant (birth weight 650 g) born at a gestational age of 23 weeks and 3 days developed an atrioventricular block (AV block). The heart rate dropped from 168/min to 90/min, and the ECG showed a Wenckebach second-degree AV block and intraventricular conduction disturbances. Echocardiography demonstrated a PDA with a large left-to-right shunt and large left atrium and left ventricle with high contractility. Within several minutes after surgical closure of the PDA, the heart rate increased, and after 30 min the AV block had improved to a 1: 1 conduction ratio. Echocardiography after 2 h revealed a significant decrease of the left ventricular and atrial dimensions. Within 12 h, the AV block completely reversed together with the intraventricular conduction disturbances. We suggest that PDA with a large left-to-right shunt and left ventricular volume overload may lead to an AV block in an ELBW infant. Surgical closure of the PDA may be indicated. Copyright (C) 2007 S. Karger AG, Basel
- …
