Improved posterobasal segment function after thrombolysis is associated with decreased incidence of significant mitral regurgitation in a first inferior myocardial infarction

OBJECTIVES: This study was designed to investigate the association between wall motion abnormalities and the occurrence of ischemic mitral regurgitation in patients with a first inferior or posterior myocardial infarction and to reassess the role of thrombolytic treatment in these patients. BACKGROUND: We previously demonstrated that thrombolytic therapy reduces the incidence of significant mitral regurgitation in patients with a first inferior myocardial infarction, but the mechanisms responsible for this decrease were not clear. METHODS: Wall motion score on two-dimensional echocardiography (16 segments) and mitral regurgitation grade (0 to 3) on Doppler color flow imaging were assessed in 95 patients (in 47 after thrombolysis) at 24 h, 7 to 10 days and 1 month after myocardial infarction. Significant mitral regurgitation was defined as moderate or severe (grade 2 or 3). RESULTS: Multivariate analysis revealed that the presence of an advanced wall motion abnormality of the posterobasal segment of the left ventricle was the most significant independent variable associated with significant mitral regurgitation: odds ratio (OR) 15.0, 90% confidence interval (CI) 1.4 to 165.6 at 24 h; OR 2.8, CI 0.9 to 9.3 at 7 to 10 days; OR 4.2, CI 1.2 to 11.4 at 1 month. Thrombolysis reduced the prevalence of advanced wall motion abnormalities in the posterobasal segment at 24 h (55% vs. 75%, OR 0.5, CI 0.2 to 0.99), 7 to 10 days (44% vs. 73%, OR 0.3, CI 0.1 to 0.7) and 1 month (36% vs. 56%, OR 0.4, CI 0.2 to 0.9). CONCLUSIONS: There is a strong association between advanced wall motion abnormalities in the posterobasal segment and significant mitral regurgitation. In this study group, thrombolysis reduced the prevalence of advanced wall motion abnormalities in the posterobasal segment and thereby reduced the incidence of significant mitral regurgitation.     

Task-dependent effects of organization and context upon comprehension of prose.

The effect of variations in the organization of information and contextual features upon comprehension of prose was tested in multiple tasks. The 4 tasks were (a) immediate free recall and recognition of (b) a factual detail, (c) the main idea, and (d) an inference. A fractional design for 32 high school students was used to accommodate many aspects of organization and context, heretofore dispersed, in one experiment. Results suggest that performance on these 4 tasks varied as a function of different dimensions of organization (structure and linkages) and context (S variables—reading achievement and sex; learning conditions—amount of time for reading; and characteristics of the materials—length, contents, prior knowledge). (17 ref) (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Are parents' gender schemas related to their children's gender-related cognitions? A meta-analysis.

Meta-analyses were conducted of 43 articles (with 48 different samples) investigating the relationship between parents' gender schemas and their offspring's gender-related cognitions. The parents' offspring ranged in age from infancy to early adulthood. Offspring measures included gender self-concept, gender attitudes toward others, gender-related interests, and occupational attitudes. Overall, a small but meaningful effect size (r = .16) indicated a significant and positive correlation between parent gender schemas and offspring measures. Specifically, parents with more traditional gender schemas were more likely than parents with more nontraditional schemas to have offspring with gender-typed cognitions about themselves or others. In addition, the magnitudes of observed effect sizes were influenced by particular moderator variables, including type of parent gender schema (gender self-concept vs. gender attitudes toward others), type of offspring gender-related cognitions, parent gender, offspring gender, offspring age, and publication characteristics. The results are cautiously interpreted as suggesting a possible influence of parents on the development of their children's gender-related thinking. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Does discovery-based instruction enhance learning?

Discovery learning approaches to education have recently come under scrutiny (Tobias & Duffy, 2009), with many studies indicating limitations to discovery learning practices. Therefore, 2 meta-analyses were conducted using a sample of 164 studies: The 1st examined the effects of unassisted discovery learning versus explicit instruction, and the 2nd examined the effects of enhanced and/or assisted discovery versus other types of instruction (e.g., explicit, unassisted discovery). Random effects analyses of 580 comparisons revealed that outcomes were favorable for explicit instruction when compared with unassisted discovery under most conditions (d = –0.38, 95% CI [?.44, ?.31]). In contrast, analyses of 360 comparisons revealed that outcomes were favorable for enhanced discovery when compared with other forms of instruction (d = 0.30, 95% CI [.23, .36]). The findings suggest that unassisted discovery does not benefit learners, whereas feedback, worked examples, scaffolding, and elicited explanations do. (PsycINFO Database Record (c) 2011 APA, all rights reserved)     

Eco System: an Internet commerce architecture

Robust electronic commerce will require several proprietary systems to interoperate. CommerceNet is proposing Eco System, a cross industry effort to build a framework of frameworks, involving both e-commerce vendors and end users. Eco System will consist of an extensible object oriented framework (class libraries, application programming interfaces and shared services) from which developers can assemble applications quickly from existing components. These applications could subsequently be reused in other applications. We are also developing a Common Business Language (CBL) that lets application agents communicate using messages and objects that model communications in the real business world. A network services architecture (protocols, APIs, and data formats) will insulate application agents from each other and from platform dependencies, while facilitating their interoperation. Functionally, Eco System fills three distinct roles. It is: a layer of middleware that facilitates agent interoperation through services such as authentication, billing, payment, and directories; an object oriented development environment that encourages the reuse of e-commerce modules (even modules that represent the product line of an entire company); and an industry roadmap and interoperability example that promotes open standards and helps technology vendors communicate with end users about product features     

Learning a theory of causality.

The very early appearance of abstract knowledge is often taken as evidence for innateness. We explore the relative learning speeds of abstract and specific knowledge within a Bayesian framework and the role for innate structure. We focus on knowledge about causality, seen as a domain-general intuitive theory, and ask whether this knowledge can be learned from co-occurrence of events. We begin by phrasing the causal Bayes nets theory of causality and a range of alternatives in a logical language for relational theories. This allows us to explore simultaneous inductive learning of an abstract theory of causality and a causal model for each of several causal systems. We find that the correct theory of causality can be learned relatively quickly, often becoming available before specific causal theories have been learned—an effect we term the blessing of abstraction. We then explore the effect of providing a variety of auxiliary evidence and find that a collection of simple perceptual input analyzers can help to bootstrap abstract knowledge. Together, these results suggest that the most efficient route to causal knowledge may be to build in not an abstract notion of causality but a powerful inductive learning mechanism and a variety of perceptual supports. While these results are purely computational, they have implications for cognitive development, which we explore in the conclusion. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Accelerated nodulosis in a patient with psoriasis and arthritis during treatment with methotrexate

A 66-year-old woman with longstanding psoriasis involving the skin presented with asymmetrical polyarthritis. Methotrexate (MTX) was given initially intramuscularly and orally. Intramuscular MTX was discontinued, and a few months after she had been taking only oral MTX she developed nodules, first in surgical incisions, and subsequently in her buttocks, thighs, legs, and arms. Reduction of the dose of oral MTX was followed by gradual diminution in size of the nodules and then total disappearance.     

Electricity privatization structural, competitive and regulatory options

Privatization is probably the most important economic and political phenomenon of this decade. This article analyses the structural, competitive, and regulatory options that are available to an existing or newly privatized electricity sector. Drawing on economic, engineering and legal insights, it presents four basic models of industry structure and examines how these structures interact with different competitive and regulatory approaches. The interactions are analysed with examples from recent US, UK and European experience. The article identifies the critical linkage between proper selection among these options and the long-term success or failure of the privatization initiative and it presents some conclusions on the causes of success and failure.     

Composite radiometric work in mining

Problems of the composite use of mine radiometry methods and the association of these methods with specific mining-geological conditions are described. The optimum conditions for ensuring the maximum efficiency of qualitative and quantitative measurements in a mine are given.Since uranium deposits are diverse in character, their classification is given here according to the particular kinds of radiometric measurements indicated, together with the most effective combinations of radiometric methods for the respective classes. The principles enumerated in the article can be used for planning radiometric work simultaneously with the planning of new mining undertakings. The article is of practical and scientific interest to mining engineers, geologists and geophysicists, engaged in surveying and working uranium deposits and the planning of ore mining undertakings.