Local form interference in biological motion perception

Peer reviewedPublisher PD

The Art of Extracting One-Dimensional Flow Properties from Multi-Dimensional Data Sets

The engineering design and analysis of air-breathing propulsion systems relies heavily on zero- or one-dimensional properties (e:g: thrust, total pressure recovery, mixing and combustion efficiency, etc.) for figures of merit. The extraction of these parameters from experimental data sets and/or multi-dimensional computational data sets is therefore an important aspect of the design process. A variety of methods exist for extracting performance measures from multi-dimensional data sets. Some of the information contained in the multi-dimensional flow is inevitably lost when any one-dimensionalization technique is applied. Hence, the unique assumptions associated with a given approach may result in one-dimensional properties that are significantly different than those extracted using alternative approaches. The purpose of this effort is to examine some of the more popular methods used for the extraction of performance measures from multi-dimensional data sets, reveal the strengths and weaknesses of each approach, and highlight various numerical issues that result when mapping data from a multi-dimensional space to a space of one dimension

Incorporating spatial correlations into multispecies mean-field models

In biology, we frequently observe different species existing within the same environment. For example, there are many cell types in a tumour, or different animal species may occupy a given habitat. In modeling interactions between such species, we often make use of the mean-field approximation, whereby spatial correlations between the locations of individuals are neglected. Whilst this approximation holds in certain situations, this is not always the case, and care must be taken to ensure the mean-field approximation is only used in appropriate settings. In circumstances where the mean-field approximation is unsuitable, we need to include information on the spatial distributions of individuals, which is not a simple task. In this paper, we provide a method that overcomes many of the failures of the mean-field approximation for an on-lattice volume-excluding birth-death-movement process with multiple species. We explicitly take into account spatial information on the distribution of individuals by including partial differential equation descriptions of lattice site occupancy correlations. We demonstrate how to derive these equations for the multispecies case and show results specific to a two-species problem. We compare averaged discrete results to both the mean-field approximation and our improved method, which incorporates spatial correlations. We note that the mean-field approximation fails dramatically in some cases, predicting very different behavior from that seen upon averaging multiple realizations of the discrete system. In contrast, our improved method provides excellent agreement with the averaged discrete behavior in all cases, thus providing a more reliable modeling framework. Furthermore, our method is tractable as the resulting partial differential equations can be solved efficiently using standard numerical techniques

"What do you Mean I Cannot Consent For My Grandmother's Medical Procedure?": Key Issues With State Default Surrogate Decision Making Laws

When a patient is unable to make medical decisions, a health care surrogate must be designated to make decisions on the patient's behalf. Studies show that fewer than 20% of patients have completed health care representative forms to legally designate a surrogate. Without a prior designation, surrogates are determined via state statute. Currently, there is no up-to-date comprehensive evaluation of state surrogate legislation. A survey of state legislative codes was conducted to determine: 1) whether the state has a default surrogate statute; 2) who is included as an acceptable legal surrogate; and 3) whether there is a hierarchy to determine a final decision-maker. Currently, 36 states have enacted some form of surrogate statute. There is little consistency between states regarding who may serve as a surrogate decision- maker. The key challenges with state laws include: 1) a narrow list of persons who qualify as allowable legal surrogates; and 2) a lack of a hierarchy to determine a final decision-maker. The results of this survey show that state surrogate decision making laws have many flaws which could affect patient care. The narrow construction of state laws can leave patients in situations where they either have no qualified surrogate under the law, or where they have multiple surrogates with competing interests who may be unable to reach consensus on the patient's medical care. State laws need to be changed so that they accurately reflect the realities of clinical practice and expanded to allow a broader spectrum of potential surrogates

Advanced digital SAR processing study

A highly programmable, land based, real time synthetic aperture radar (SAR) processor requiring a processed pixel rate of 2.75 MHz or more in a four look system was designed. Variations in range and azimuth compression, number of looks, range swath, range migration and SR mode were specified. Alternative range and azimuth processing algorithms were examined in conjunction with projected integrated circuit, digital architecture, and software technologies. The advaced digital SAR processor (ADSP) employs an FFT convolver algorithm for both range and azimuth processing in a parallel architecture configuration. Algorithm performace comparisons, design system design, implementation tradeoffs and the results of a supporting survey of integrated circuit and digital architecture technologies are reported. Cost tradeoffs and projections with alternate implementation plans are presented

Using Blogs to Foster Inquiry, Collaboration, and Feedback in Pre-Service Teacher Education

This chapter presents a critical case study on the use of information technology in a pre-service teacher education program. The authors integrated Weblogs (blogs) into two constructivist-oriented teacher preparation courses with the goal of helping students learn to think like a teacher through enhanced inquiry, collaboration, and feedback. The authors found that, through the use of blogs, pre-service teaching candidates grew in their abilities to reflect on their own teaching and to provide constructive comments to peers. The authors’ experience also indicated that while instructor and peer feedback via blogs was valuable, it functioned best when paired with face-to-face meetings between the instructors and students. They discussed design principles for combining online and face-to-face environments and offer possibilities for the expanded use of blogs in pre-service teacher education

Stochastic reaction & diffusion on growing domains: understanding the breakdown of robust pattern formation

Many biological patterns, from population densities to animal coat markings, can be thought of as heterogeneous spatiotemporal distributions of mobile agents. Many mathematical models have been proposed to account for the emergence of this complexity, but, in general, they have consisted of deterministic systems of differential equations, which do not take into account the stochastic nature of population interactions. One particular, pertinent criticism of these deterministic systems is that the exhibited patterns can often be highly sensitive to changes in initial conditions, domain geometry, parameter values, etc. Due to this sensitivity, we seek to understand the effects of stochasticity and growth on paradigm biological patterning models. In this paper, we extend spatial Fourier analysis and growing domain mapping techniques to encompass stochastic Turing systems. Through this we find that the stochastic systems are able to realize much richer dynamics than their deterministic counterparts, in that patterns are able to exist outside the standard Turing parameter range. Further, it is seen that the inherent stochasticity in the reactions appears to be more important than the noise generated by growth, when considering which wave modes are excited. Finally, although growth is able to generate robust pattern sequences in the deterministic case, we see that stochastic effects destroy this mechanism for conferring robustness. However, through Fourier analysis we are able to suggest a reason behind this lack of robustness and identify possible mechanisms by which to reclaim it

Energy dependence of ratios of multiplicities and their slopes for gluon and quark jets

The difference between the ratio of multiplicities and the ratio of their derivatives on energy for gluon and quark jets is calculated up to next-to-next-to leading order of perturbative QCD. Its non-zero value is uniquely defined by the running property of the QCD coupling constant. It is shown that this difference is rather small compared to values which can be obtained from experimental data. This disagreement can be ascribed either to strong non-perturbative terms or to experimental problems with a scale choice, jets separation and inadequate assignement of soft particles to jets.Comment: 5 pages, LATEX, no Figs; submitted to JETP Let

A Conscience Sensitive Approach To Ethics and Teaching Caring Attitudes

An I.U. Conscience Project and HELP Collaboration. The article describes models for teaching ethics and caring attitudes to undergraduate medical students in both formal and informal medical education curriculum. Competency based curriculum is discussed

Progress in conscience-sensitive psychiatry: assessment, diagnosis and treatment planning

Study of the relationship between episodic or continuous moral malfunctioning and psychopathology is an undeveloped field in child and adolescent psychiatry. An empirically derived theory of conscience provides a normative base from which to launch such studies. This work reviews five normative stages of functioning within five domains of conscience: conceptualization, moralization of attachment, moral-emotional responsiveness, moral valuation, and moral volition. Current professional guidelines for the doctor-patient relationship, psychiatric assessment, diagnostic categorization, and treatment planning address conscience functioning sometimes directly, sometimes indirectly, and sometimes not at all. A case report is provided to illustrate progress already made in conscience sensitive clinical psychiatry. Further advances may begin with consideration of proposed hypothetical models, comporting with recent research, which describe progressive impairment involving both delay and deviancy in conscience functioning