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Background Pharmacist-prescribed hormonal contraception (HC) may offer additional avenues of access for patients; however, it is unknown whether pharmacists would support over-the-counter access to contraception over pharmacist-prescribed models. Objective The objective of this study was to understand how North Carolina (NC) pharmacists believed HC should be classified and how pharmacist and pharmacy characteristics were associated with those beliefs. Methods This study was a secondary analysis of a cross-sectional, anonymous, online survey completed by 587 licensed NC pharmacists. The primary outcome of interest was how pharmacists believed HC should be classified: prescription-only, pharmacist-prescribed, behind-the-counter, or over-the-counter. Multinomial bivariate and multivariable regression analyses were conducted to describe the association between pharmacist and pharmacy characteristics with the outcomes of interest through odds ratios and adjusted odds ratios, respectively. Chi-square tests were used to examine the association of geographic location with distribution of attitudes toward HC classification. Results Fifty-one percent of NC pharmacists supported classification of HC as pharmacist-prescribed, while 23% supported non-prescription (behind- or over-the-counter) classification. Controlling for pharmacist demographics and pharmacy characteristics, completing residency training was significantly associated with supporting pharmacist-prescribed vs prescription-only classification (adjusted odds ratio (aOR) = 2.55, P = .02). Pharmacists had higher odds of supporting pharmacist-prescribed vs prescription-only HC if they agreed that they were well trained to do so (aOR = 3.14, P < .01). Distribution of attitudes about classification of HC did not significantly differ by geographic location (P = .14). Conclusions Most NC pharmacists support deviating from the current prescription-only classification of HC, with more support for pharmacist-prescribed classification. Continuing education programs should focus on training pharmacists to feel more confident prescribing HC.

We develop finite element data structures for T-splines based on Bézier extraction generalizing our previous work for NURBS. As in traditional finite element analysis, the extracted Bézier elements are defined in terms of a fixed set of polynomial basis functions, the so-called Bernstein basis. The Bézier elements may be processed in the same way as in a standard finite element computer program, utilizing exactly the same data processing arrays. In fact, only the shape function subroutine needs to be modified, all other aspects of a finite element program remaining the same. A byproduct of the extraction process is the element extraction operator. This operator localizes the topological and global smoothness information to the element level, and represents a canonical treatment of T-junctions, referred to as "hanging nodes" in finite element analysis and a fundamental feature of T-splines. A detailed example is presented to illustrate the ideas.

Isogeometric analysis is a versatile tool for failure analysis. On the one hand, the excellent control over the inter-element continuity conditions enables a natural incorporation of continuum constitutive relations that incorporate higher-order strain gradients, as in gradient plasticity or damage. On the other hand, the possibility of enhancing a basis with discontinuities by means of knot insertion makes isogeometric finite elements a suitable candidate for modeling discrete cracks. Both possibilities are described and will be illustrated by examples.

The possibility of enhancing a B-spline basis with discontinuities by means of knot insertion makes isogeometric finite elements a suitable candidate for modeling discrete cracks. In this contribution we use isogeometric finite elements to discretize the cohesive zone formulation for failure in materials. In the case of a pre-defined interface, non-uniform rational B-splines are used to obtain an efficient discretization. In the case that propagating cracks are considered, T-splines are found to be more suitable, due to their ability to generate localized discontinuities. Various numerical simulations demonstrate the suitability of the isogeometric approach to cohesive zone modeling.

Continuum damage formulations are commonly used for the simulation of diffuse fracture processes. Implicit gradient damage models are employed to avoid the spurious mesh dependencies associated with local continuum damage models. The C0-continuity of traditional finite elements has hindered the study of higher order gradient damage approximations. In this contribution we use isogeometric finite elements, which allow for the construction of higher order continuous basis functions on complex domains. We study the suitability of isogeometric finite elements for the discretization of higher order gradient damage approximations. © 2011 John Wiley & Sons, Ltd.

The first paper on isogeometric analysis appeared only five years ago [1], and the first book appeared last year [2]. Progress has been rapid. Isogeometric analysis has been applied to a wide variety of problems in solids, fluids and fluid-structure interactions. Superior accuracy to traditional finite elements has been demonstrated in all cases. In addition, it has been shown that isogeometric analysis provides an efficient framework for the design through analysis paradigm. In this contribution we present two examples which illustrate the potential of T-splines, a powerful generalization of NURBS, the CAD industry standard. The first example utilizes T-splines for a problem of propagating cracks. Smoothly turning discontinuities can be introduced in T-splines through local knot insertion. The possibility of enhancing a T-spline basis with discontinuities makes isogeometric finite elements suitable for the capturing of discontinuities, in particular, cracks. From an implementation point of view, the concept of Bézier extraction [3] allows for a unified approach to NURBS and T-splines, and will allow this approach to be extended to T-splines of arbitrary topology. The second example demonstrates the enabling power of T-splines in a design through analysis framework. A trimless T-spline automotive bumper is generated and then used directly in an LS-DYNA vibrations analysis [4]. T-splines can describe shapes of arbitrary topological complexity while maintaining a smooth analysis-suitable basis. This makes them an attractive alternative to classical finite elements for many problems of engineering interest. For such problems, the isogeometric paradigm can be invoked thus eliminating the analysis costs associated with geometry clean-up, defeaturing and mesh generation. The two numerical simulations considered in this work demonstrate the capability of the T-spline basis to meet the stringent needs of analysis while providing the flexibility to overcome design through analysis bottlenecks. Specifically, T-splines were found to give efficient discretizations in terms of the number of degrees of freedom and the required computational effort. We anticipate that T-splines and isogeometric analysis will continue to provide efficient solutions to many important problems in computational mechanics.