Search results for "category theory"
showing 10 items of 1172 documents
Adaptive dual control in one biomedical problem
2003
In this paper, the following biomedical problem is considered. People are subjected to a certain chemotherapeutic treatment. The optimal dosage is the maximal dose for which an individual patient will have toxicity level that does not cross the allowable limit. We discuss sequential procedures for searching the optimal dosage, which are based on the concept of dual control and the principle of optimality. According to the dual control theory, the control has two purposes that might be conflicting: one is to help learning about unknown parameters and/or the state of the system (estimation); the other is to achieve the control objective. Thus the resulting control sequence exhibits the closed…
Short review: Field recovery and potential information value of small elements of the skeleton
2011
The recovery of small elements of the skeleton (e.g. hyoid, carpals, and hand and foot phalanges) is one of the established tasks of the archaeologist and physical anthropologist when working in the field, whether in an archaeological or forensic context. In the present work, we illustrate the field location of ossified laryngeal cartilages, hand sesamoids, and the medial clavicular epiphyses. The potential information offered by these elements is briefly summarized. The frequency of these elements observed in a cemetery dating from 1943 indicates the possibility that these elements could be found in other contexts at a higher frequency than expected.
Non-compact myocardium assessment by cardiac magnetic resonance: dependence on image analysis method
2018
To compare image analysis methods for the assessment of left ventricle non-compaction from cardiac magnetic resonance (CMR) imaging. CMR images were analyzed in 20 patients and 10 normal subjects. A reference model of the MR signal was introduced and validated based on image data. Non-compact (NC) myocardium size and distribution were assessed by tracing a single, continuous contour delimiting trabeculated region (Jacquier) or by one-by-one selection of trabeculae (Grothoff). The global non-compact/compact (NC/C) ratio, the NC mass, and the segmental NC/C ratio were assessed. Results were compared with the reference model. A significant difference between Grothoff and Jacquier approaches in…
From algorithmic computing to direct retrieval: Evidence from number and alphabetic arithmetic in children and adults
1998
A number of theories of mental arithmetic suggest that the ability to solve simple addition and subtraction problems develops from an algorithmic strategy toward a strategy based on the direct retrieval of the result from memory. In the experiment presented here, 2nd and 12th graders were asked to solve two tasks of number and alphabet arithmetic. The subjects transformed series of 1 to 4 numbers or letters (item span) by adding or subtracting an operand varying from 1 to 4 (operation span). Although both the item and operation span were associated with major and identical effects in the case of both numbers and letters at 2nd grade, such effects were clearly observable only in the case of …
Retrospective analysis of fixed drug eruptions among patients attending a tertiary care center in Southern India
2014
A reanalysis of the center for epidemiological studies depression scale (CES-D) using non-parametric item response theory
2020
Abstract The “Center for Epidemiological Studies Depression Scale” (CES-D; Radloff, 1977 ) is a questionnaire used world-wide to measure depressive symptoms. Although the original four-factor-structure has been widely accepted and replicated, some studies point to other factor-structures like a one- and two-factor-structure. The goal of the current study was to evaluate the factor structure of the CES-D (one-, two- and four-factor-structure), which was found using classical test theory (CTT), with two non-parametric item-response-theory-models (Mokken-Scaling; Monotone-homogeneity-model; MHM and Double-monotonicity-model; DMM). To this end, a representative German sample was analyzed (N = 2…
X-inactivation pattern in three cases of X/autosome translocation.
1978
We describe an X/15 translocation which was balanced in a phenotypically normal mother [46,X,t(X;15)(p22;q15)] and unbalanced in her phenotypically abnormal daughter [46,X,der(X),t(X;15)(p22;q15)mat]. A third case involves a balanced X/21 translocation in a girl with a multiple congenital anomaly-retardation syndrome [46,X,t(X;21)(p11;p11?)]. 5-BrdU acridine orange banding on lymphocytes revealed late replication of the normal X chromosome in the mother and of the normal or abnormal X chromosome in the two other cases. Our findings are only partially consistent with previous observations. All X-inactivation patterns can be explained by random inactivation and subsequent selection against sp…
Genetic and environmental contribution to postural balance of older women in single and dual task situations
2005
Abstract The purpose of the present study was to examine the effect of a second task on postural balance and to determine the role of genetic influences on postural balance when dual tasking among 206 monozygotic and 227 dizygotic female twins, aged 63–76 years. Balance was measured as medio-lateral and antero-posterior velocity of the centre of pressure (COP) (mm/s) and velocity moment (mm2/s) while standing on a force platform. Doing an arithmetic task increased movement of the COP while the hand motor task had no effect on movement of the COP. The genetic contribution to balance in the single task situation was minor (14%, 95% confidence interval, CI: 11–35%) whereas in the dual task sit…
On monadic quantale algebras: basic properties and representation theorems
2010
Motivated by the concept of quantifier (in the sense of P. Halmos) on different algebraic structures (Boolean algebras, Heyting algebras, MV-algebras, orthomodular lattices, bounded distributive lattices) and the resulting notion of monadic algebra, the paper introduces the concept of a monadic quantale algebra, considers its properties and provides several representation theorems for the new structures.
On a paper of Beltrán and Shao about coprime action
2020
Abstract Assume that A and G are finite groups of coprime orders such that A acts on G via automorphisms. Let p be a prime. The following coprime action version of a well-known theorem of Ito about the structure of a minimal non-p-nilpotent groups is proved: if every maximal A-invariant subgroup of G is p-nilpotent, then G is p-soluble. If, moreover, G is not p-nilpotent, then G must be soluble. Some earlier results about coprime action are consequences of this theorem.