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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 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.

The article offers information on the concept of career, job, profession and vocation in relevance to theological education. It explores the issues of acknowledging a person's work in theological education as an appropriate vocation. It presents a thorough discussion on the characteristics and notion of vocation, which is regarded as a divine call to God's service.

This article compares native residents’ opinions and perceptions regarding immigration using a representative survey from a pair of matched North Carolina counties – one that experienced recent growth of its foreign-born population and one that did not. Drawing from several theoretical perspectives, including group threat, contact theory, and symbolic politics, we formulate and empirically evaluate several hypotheses. Results provide limited evidence that competition and threat influence formation of opinions about immigration, with modest support for claims that parents with school-aged children harbor more negative views of immigration than their childless counterparts. Except for residents in precarious economic situations, these negative opinions appear unrelated to the immigrant composition of the community. Claims that the media promotes negative views of immigration receive limited support, but this relationship is unrelated to the volume of local immigration. Finally, sustained contacts with foreign-born residents outside work environments are associated with positive views of immigration, but superficial contacts appear to be conducive to anti-immigration sentiments. Political orientation, educational attainment, and indicators of respondents’ tolerance for diversity explain most of the difference between the two counties in overall support for immigration. [ABSTRACT FROM AUTHOR]

Previous research has made a beginning in addressing the importance of methodological differences in Web-based research. The present paper presents four studies investigating whether sample type, financial incentives, time when personal information is requested, table design, and method of obtaining informed consent influence dropout and sample characteristics (both demographics and measured attitudes). Undergraduates were less likely to drop out than nonstudents, and nonstudents offered a financial incentive were less likely to drop out than those offered no incentive. Complex tables, tables that were too wide, requests for personal information on the first page, and the imposing of additional informed consent procedures each provoked early dropout. As was expected, nonstudents and those presented with complex tables showed more measurement error and attitude differences. Asking for personal information and imposing additional consent procedures affected the demographic makeup, raising challenges to external validity. [ABSTRACT FROM AUTHOR]

Presents a formulation designed to succeed in attacking broad-band electromagnetic induction problems numerically when primary magnetic fields penetrate a metallic object negligibly to moderately. Information on the complete system of equations and scattered field solution; Analytical solution for sphere and domain of thin skin depth approximation (TSA) validity; Numerical accuracy of the TSA.

Investigates methods used in a Web-based psychology study of jury decision making in capital cases to see whether they affect dropout rates or the substantive results. Effect of sample type; Effect of monetary incentives or rewards; Effect of requiring participants to enter personal information; Effect of weekend or weekday participation.

Examines the capability of redundant robotic manipulators to reconfigure itself from a singular posture to a nonsingular posture through self-motion. Criteria for classifications of escapable and inescapable singularities; Examples that demonstrate the use the criteria; Method that gives the best self-motion direction among a set of feasible ones.

HIV vaccine development has been hindered by significant challenges over four decades. Despite persistent efforts, all efficacy trials to date have yielded disappointing results. This has pushed the field back to the discovery phase and created uncertainty about the future involvement of large pharmaceutical companies. Currently, the HIV vaccine landscape is dominated by startup biotech firms, which face a complex array of obstacles. These include evolving HIV prevention methods, waning interest in vaccine research, and difficulties securing sustainable funding. This viewpoint explores the challenges faced by these biotech companies and the support mechanisms necessary for their continued involvement in HIV vaccine development. By leveraging insights from both pharmaceutical and biotech sectors, we propose a multi-faceted approach that includes enhanced communication, fostering innovation, and implementing strategic funding models.

Purpose: We conducted our study to compare the number of preneoplastic lesions in the airways and nodules in the pulmonary parenchyma of patients with resected non-small cell lung cancer with the patients whose treatment included chest radiotherapy., Experimental Design: Patients were eligible if they had successfully resected stage I and II non-small cell lung cancer or advanced stage non-small cell or small cell lung cancer treated with chest radiotherapy with or without chemotherapy and were free of cancer for >2 years. Patients underwent a history and physical examination, white light and fluorescence bronchoscopy, and computerized tomography of the chest. The airway epithelium was examined for preneoplastic histological changes, and the pulmonary parenchyma was examined for the presence of nodules., Results: Twenty-nine patients at risk for lung cancer were studied between 1997 and 1999. Two patients treated with chest radiotherapy had an area of moderate dysplasia (n=1) and carcinoma in situ (n=1), whereas one patient treated with surgical resection alone had an area of mild dysplasia. Six other patients had metaplasia detected in their airway epithelium. Ten of the 13 patients treated with chest radiotherapy had pulmonary nodules compared with 5 of the 13 patients treated with surgical resection alone., Conclusions: Mild dysplasia, moderate dysplasia, severe dysplasia, and carcinoma in situ are unusual in patients with resected lung cancer who have stopped smoking for an extended period of time. Patients with lung cancer treated with chest irradiation may be at higher risk for preneoplastic lesions and pulmonary nodules than patients treated with surgical resection alone, but additional patients will need to be studied.