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Many Variations (many + variation)

Distribution by Scientific Domains

Medical Sciences	50%

Selected Abstracts

Advancement Flaps: A Basic Theme with Many Variations

DERMATOLOGIC SURGERY, Issue 2005
Ravi Krishnan MD
Background. The advancement flap involves the linear advancement of tissue in one direction. Despite its straightforwardness and simple concept, it can be used to close a variety of defects, ranging from small defects on the scalp or extremities to large, complicated defects involving cosmetic units on the face. Objectives. To provide a basic and useful review for the indications, advantages, disadvantages, and techniques for the use of advancement flaps in the reconstruction of defects in dermatologic surgery. Materials and Methods. We performed a literature search for articles discussing advancement flaps and compiled a brief review of our findings. Results. The movement of the advancement flap must be balanced by the blood supply of the flap. The excision of Burow's triangles along various aspects of the advancement flap can increase movement and improve cosmesis of the flap. The types of advancement flaps discussed include the single advancement flap, double advancement flap, A-T flap (O-T flap), Burow's triangle flap (Burow's wedge flap), crescenteric advancement flap, island pedicle flap (V-Y flap), helical rim advancement flap, and facelift flap. Conclusion. Advancement flaps are versatile and useful basic flaps for repairing defects. [source]

A practical large-strain solid finite element for sheet forming

INTERNATIONAL JOURNAL FOR NUMERICAL METHODS IN ENGINEERING, Issue 4 2005
Jue Wang
Abstract An alternative approach for developing practical large-strain finite elements has been introduced and used to create a three-dimensional solid element that exhibits no locking or hourglassing, but which is more easily and reliably derived and implemented than typical reduced-integration schemes with hourglassing control. Typical large-strain elements for forming applications rely on reduced integration to remove locking modes that occur with the coarse meshes that are necessary for practical use. This procedure introduces spurious zero-energy deformation modes that lead to hourglassing, which in turn is controlled by complex implementations that involve lengthy derivations, knowledge of the material model, and/or undetermined parameters. Thus, for a new material or new computer program, implementation of such elements is a daunting task. Wang,Wagoner-3-dimensions (WW3D), a mixed, hexahedral, three-dimensional solid element, was derived from the standard linear brick element by ignoring the strain components corresponding to locking modes while maintaining full integration (8 Gauss points). Thus, WW3D is easily implemented for any material law, with little chance of programming error, starting from programming for a readily available linear brick element. Surprisingly, this approach and resulting element perform similarly or better than standard solid elements in a series of numerical tests appearing in the literature. The element was also tested successfully for an applied sheet-forming analysis problem. Many variations on the scheme are also possible for deriving special-purpose elements. Copyright © 2005 John Wiley & Sons, Ltd. [source]

A systematic review of trend studies of women seeking termination of pregnancy

JOURNAL OF CLINICAL NURSING, Issue 22 2008
Wendy Abigail
Aims and objectives., This article reports a systematic review of trend studies (1995,2006) which answers five questions: What are the patterns of: 1,Age of women seeking termination of pregnancy; 2,First ever pregnancy ending in a termination; 3,Contraception usage at the time of conception; 4,Contraception chosen immediately postoperatively; and 5,Referral sources to termination of pregnancy services. Background., Fertility patterns are changing and there is evidence to indicate that the numbers of older women conceiving for the first time are increasing. At the same time, there are new methods of contraception widely available. Little is known about the implications of these changes on termination patterns. Design., An extensive electronic search of databases such as CINAHL, MEDLINE® In-Process (OVID) and was conducted from January 1995,June 2006 for trend studies in pregnancy terminations. Methods., Articles chosen were based on trend studies greater than five years, contained primary quantitative research and official government statistical reports. Results., Results of the search showed age that was unable to be compared because of the many variations in measurements and time periods, and there was only limited research worldwide of trends in contraception at the time of conception in relation to a termination of pregnancy. Additionally, there were no studies worldwide in the past 11 years, which specifically examined trends in the characteristics of the number of first-ever pregnancies which ended in a termination, contraception choices postoperative to a termination of pregnancy, or referral source to a termination of pregnancy provider. Conclusion., Little is reported in the literature on trends in the five characteristics related to pregnancy termination. Relevance to clinical practice., Evidence about the changing patterns of women seeking pregnancy termination is needed to inform policy and practice, and to ensure that health promotion strategies are underpinned by accurate information that reflects the needs of the populations of women in relation to their reproductive health. [source]

Searching for mid-term variations in different aspects of solar activity , looking for probable common origins and studying temporal variations of magnetic polarities

MONTHLY NOTICES OF THE ROYAL ASTRONOMICAL SOCIETY, Issue 1 2007
E. Forgács-Dajka
ABSTRACT Several studies have examined the temporal variability of the solar activity, and many variations are reported in the literature. We also (re)analyse the statistical properties of the following kinds of data series of solar activity phenomena: magnetic synoptic charts, hemispherical relative sunspot numbers, solar flare index, coronal index, solar radio flux, interplanetary magnetic field and proton speed in the solar wind, in order to find common mid-term periods during solar cycles 21,23. As a new approach, we focus on the magnetic polarity relations and we define new quantities (e.g. magnetic positive,negative polarity asymmetry) to explore the connections between several aspects of the solar activity from different points of view. According to our survey, the mid-term periodicities (1,2 yr) are manifest in almost all data with the exception of the coronal index and the 10.7-cm solar flux data. In the case of these latter two we note that these surveys produce global data on the solar corona, so the Sun is studied on these bandwidths as a star. Besides these, with the accumulation of helioseismic data over the last 10 yr, it has become possible to study the temporal variation in the rotational rate residuals in tachocline region. In addition, we examine possible common origins of different activity markers and/or possible connections to differential rotation. [source]