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Pulmonary arteriovenous malformations (PAVMs) occur in 30% to 50% of patients with hereditary hemorrhagic telangiectasia. Clinical presentations vary from asymptomatic disease to complications resulting from the right to left shunting of blood through the PAVM such as paradoxical stroke, brain abscesses, hypoxemia, and cardiac failure. Radiology plays an important role both in the diagnosis and treatment of PAVM. Based on different clinical scenarios, the appropriate imaging study has been reviewed and is presented in this document. The American College of Radiology Appropriateness Criteria are evidence-based guidelines for specific clinical conditions that are reviewed annually by a multidisciplinary expert panel. The guideline development and revision process support the systematic analysis of the medical literature from peer reviewed journals. Established methodology principles such as Grading of Recommendations Assessment, Development, and Evaluation or GRADE are adapted to evaluate the evidence. The RAND/UCLA Appropriateness Method User Manual provides the methodology to determine the appropriateness of imaging and treatment procedures for specific clinical scenarios. In those instances where peer reviewed literature is lacking or equivocal, experts may be the primary evidentiary source available to formulate a recommendation. [ABSTRACT FROM AUTHOR]

The studies of mesoscopic inhomogeneity of conducting polymers using scanning probe techniques such as Kelvin probe force microscopy (KFM) and current-sensing atomic force microscopy (CS-AFM) are presented.

Current idealized forward models for electromagnetic induction (EMI) response can be defeated by the characteristic material and geometrical heterogeneity of realistic unexploded ordnance (UXO). A new, physically complete modeling system was developed that includes all effects of these heterogeneities and their interactions within the object, in both near and far fields. The model is fast enough fur implementation in inversion processing algorithms. A method is demonstrated for extracting the model parameters by straightforward processing of data from a defined measurement protocol. Depending on the EMI sensor used for measurements, the process of inferring model parameters is more or less ill-posed. More complete data can alleviate the problem. For a given set of data, special numerical treatment is introduced to take the best advantage of the data and obtain reliable model parameters. The resulting fast model is implemented in a pattern matching treatment of measurements by which signals from a UXO are identified within a series of those from unknown targets. Preliminary results show that this fast model is promising for use in processing of this kind. The inherent difficulties of target identification are examined, and solutions for resolving these difficulties are discussed. Index Terms--Electromagnetic induction (EMI), fundamental excitation modes, ill-conditioning, inversion, pattern matching, spheroid, unexploded ordnance (UXO).

The minimum torque norm control scheme for redundant manipulators has long been known to exhibit instabilities. In this paper, an analysis is made of a class of acceleration-level redundancy resolution schemes that includes the minimum torque, minimum acceleration, and other well known schemes. It is proved that divergence of joint velocity norm to infinity in finite time is possible, and in fact does occur for self motions of mechanisms with one degree of redundancy under almost all such schemes in the class. The schemes that do not diverge in finite time are associated with conserved quantities and include minimum acceleration norm and dynamically consistent redundancy resolution schemes. Besides the divergence, all these schemes can exhibit local instabilities in the form of abrupt increases in joint velocities and torques. Simulations are presented that illustrate the types of divergence and instability. The details of the analysis should be useful to designers seeking to modify these resolution schemes. For example, it is proved that linear dissipation of nullspace velocity cannot stabilize the algorithms. Index Terms--Dynamically consistent control, instability, minimum torque control, optimization, redundancy resolution.

The case of a 34-year-old man with eosinophilia is described. Eosinophilia is caused by excess levels of a white blood cell called eosinophils. The excess eosinophil levels can damage organs. Researchers also found excess levels of natural killer cells, as well as interleukin-15 and interleukin-2. The patient's symptoms may have been triggered by an infectious organism, which triggered the production of interleukin-15 and interleukin-2, which in turn triggered the activation of natural killer cells. The activated killer cells then produced proteins that stimulate eosinophil production.

The extended Jacobian method is a popular approach for controlling a kinematically redundant arm which allows one to resolve redundancy by locally optimizing an objective function and to gain repeatability for a cyclic end effector trajectory. It is a special case of a family of methods called constraint function methods. It has been found that the occurrence of algorithmic singularities can cause severe difficulties and the advantages of the methods such as repeatability might no longer exist. The purpose of this paper is to study the characteristics of algorithmic singularities, especially those of corank 1. A result of the authors on kinematic singularities is used to obtain a sufficient condition for the existence of solution paths at algorithmic singularities of the constrained function method. The phenomenon of branch repeatability is shown to occur at an algorithmic singularity. We also show that the extended Jacobian method cannot successfully optimize the objective function beyond the singularity without loss of continuity of the joint derivative. Examples are given to demonstrate the use of our theoretical results. Index Terms - Algorithmic singularity, extended Jacobian method, redundancy resolution.