Supernatants of rat skeletal muscle homogenates were fractionated by differential centrifugation and by zonal centrifugation in sucrose density gradients. Cytochrome oxidase was employed as an enzymatic marker for locating mitochondria. The subcellular fractions were also assayed for their ability to prevent the ATP-induced contraction of myofibrils. Both the mitochondrial and microsomal fracti...

Background: Double layer stents (DLS) were designed to overcome the limitations of plastic stents (PS) and self-expandable metal stents (SEMS) in palliating inoperable malignant biliary obstructions (MBO). Aims: Primary outcomes are stent patency period, occlusion rates and adverse events. Methods: Study Selection Criteria: Studies using DLS, SEMS and PS for palliation of patients with inoperab...

Differences in ribonudeic acid (RNA) composition were observed by various authors between the liver cell fractions isolated by differential centrifugation. While authors generally agree that the nuclear R N A differs from the cytoplasmic RNA, disagreement exists with respect to the composition of the R N A isolated from cytoplasmic fractions (1-8). Such analysis was usually carried out on three...

Concept learning in description logics (DLs) is similar to binary classification in traditional machine learning. The difference is that in DLs objects are described not only by attributes but also by binary relationships between objects. In this paper, we develop the first bisimulation-based method of concept learning in DLs for the following setting: given a knowledge base KB in a DL, a set o...

PURPOSE To investigate the relationship between retinal nerve fiber layer (RNFL) thickness and peripheral grating resolution acuity (PGRA) as well as differential light sensitivity (DLS) in healthy subjects and patients with early glaucoma. The agreement between estimates of retinal ganglion cell (GC) density from each functional test is explored. METHODS PGRA was measured in 24 patients with...

Combining knowledge representation and reasoning formalisms like description logics (DLs), temporal logics, and logics of space, is worthwhile but difficult. It is worthwhile because usually realistic application domains comprise various aspects of the world, thus requiring suitable combinations of formalisms modeling each of these aspects. It is difficult because the computational behavior of ...

1. Human placenta microsomes active in blood coagulation have been prepared by a combination of differential centrifugation, density gradient centrifugation, and extraction with butanol-benzene mixtures. Human brain particles have been prepared from acetone-dried brain by extraction with sodium chloride solutions, differential centrifugation, and extraction with butanol-benzene mixtures. 2. Pla...

With the advent of the Internet came the promise of global information access. In keeping with this promise, Digital Libraries (DLs) began to emerge across the world as a method of providing structured information to their users. These DLs are often created using proprietary monolithic software that is usually difficult to customise and extend. The Open Digital Library (ODL) project was created...

Role Based Access Control (RBAC) is a methodology for providing users in an IT system specific permissions like write or read to users. It abstracts from specific users and binds permissions to user roles. Similarly, one can abstract from specific documents and bind permission to document types. In this paper, we apply Description Logics (DLs) to formalize RBAC. We provide a thorough discussion...