A Normative Theory of Forgetting: Lessons from the Fruit Fly

Recent experiments revealed that the fruit fly Drosophila melanogaster has a dedicated mechanism for forgetting: blocking the G-protein Rac leads to slower and activating Rac to faster forgetting. This active form of forgetting lacks a satisfactory functional explanation. We investigated optimal decision making for an agent adapting to a stochastic environment where a stimulus may switch between being indicative of reward or punishment. Like Drosophila, an optimal agent shows forgetting with a rate that is linked to the time scale of changes in the environment. Moreover, to reduce the odds of missing future reward, an optimal agent may trade the risk of immediate pain for information gain and thus forget faster after aversive conditioning. A simple neuronal network reproduces these features. Our theory shows that forgetting in Drosophila appears as an optimal adaptive behavior in a changing environment. This is in line with the view that forgetting is adaptive rather than a consequence of limitations of the memory system.

Development of meta-representations: Procedural metacognition and the relationship to Theory of Mind

In several studies it was shown that metacognitive ability is crucial for children and their success in school. Much less is known about the emergence of that ability and its relationship to other meta-representations like Theory of Mind competencies. In the past years, a growing literature has suggested that metacognition and Theory of Mind could theoretically be assumed to belong to the same developmental concept. Since then only a few studies showed empirically evidence that metacognition and Theory of Mind are related. But these studies focused on declarative metacognitive knowledge rather than on procedural metacognitive monitoring like in the present study: N = 159 children were first tested shortly before making the transition to school (aged between 5 1/2 and 7 1/2 years) and one year later at the end of their first grade. Analyses suggest that there is in fact a significant relation between early metacognitive monitoring skills (procedural metacognition) and later Theory of Mind competencies. Notably, language seems to play a crucial role in this relationship. Thus our results bring new insights in the research field of the development of meta-representation and support the view that metacognition and Theory of Mind are indeed interrelated, but the precise mechanisms yet remain unclear.

AN OCCUPATIONAL INJURY MANAGEMENT INFORMATION SYSTEM FOR THE UNIVERSITY OF TEXAS HEALTH SCIENCE CENTER AT HOUSTON

The purpose of this research and development project was to develop a method, a design, and a prototype for gathering, managing, and presenting data about occupational injuries.^ State-of-the-art systems analysis and design methodologies were applied to the long standing problem in the field of occupational safety and health of processing workplace injuries data into information for safety and health program management as well as preliminary research about accident etiologies. The top-down planning and bottom-up implementation approach was utilized to design an occupational injury management information system. A description of a managerial control system and a comprehensive system to integrate safety and health program management was provided.^ The project showed that current management information systems (MIS) theory and methods could be applied successfully to the problems of employee injury surveillance and control program performance evaluation. The model developed in the first section was applied at The University of Texas Health Science Center at Houston (UTHSCH).^ The system in current use at the UTHSCH was described and evaluated, and a prototype was developed for the UTHSCH. The prototype incorporated procedures for collecting, storing, and retrieving records of injuries and the procedures necessary to prepare reports, analyses, and graphics for management in the Health Science Center. Examples of reports, analyses, and graphics presenting UTHSCH and computer generated data were included.^ It was concluded that a pilot test of this MIS should be implemented and evaluated at the UTHSCH and other settings. Further research and development efforts for the total safety and health management information systems, control systems, component systems, and variable selection should be pursued. Finally, integration of the safety and health program MIS into the comprehensive or executive MIS was recommended. ^

Trends in health information seeking among cancer and non-cancer adults between 2003 and 2005: A descriptive analysis of Health Information National Trends Survey (HINTS) data

Cancer is the second leading cause of death in the United States. With the advent of new technologies, changes in health care delivery, and multiplicity of provider types that patients must see, cancer care management has become increasingly complex. The availability of cancer health information has been shown to help cancer patients cope with the management and effects of their cancers. As a result, more cancer patients are using the internet to find resources that can aid in decision-making and recovery. ^ The Health Information National Trends Survey (HINTS) is a nationally representative survey designed to collect information about the experiences of cancer and non-cancer adults with health information sources. The HINTS survey focused on both conventional sources as well as newer technologies, particularly the internet. This study is a descriptive analysis of the HINTS 2003 and HINTS 2005 survey data. The purpose of the research is to explore the general trends in health information seeking and use by US adults, and especially by cancer patients. ^ From 2003 to 2005, internet use for various health-related activities appears to have increased among adults with and without cancer. Differences were found between the groups in the general trust in information media, particularly the internet. Non-cancer respondents tended to have greater trust in information media than cancer respondents. ^ The latter portion of this work examined characteristics of HINTS respondents that were thought to be relevant to how much trust individuals placed in the internet as a source of health information. Trust in health information from the internet was significantly greater among younger adults, higher-earning households, internet users, online seekers of health or cancer information, and those who found online cancer information useful. ^

DISEASE-RELATED INFORMATION NEEDS OF CANCER PATIENTS AGES 11-20: A COMPARISON OF PATIENT-PARENT AND PATIENT-PHYSICIAN PERCEPTIONS

Innovative, aggressive treatments and prolonged survival rates for patients with childhood cancers have placed new demands on the patient, parent and physician. As a result, counterproductive coping behaviors are often noted in adolescent cancer patients.^ One of the main ways the environment is manipulated by the individual to achieve personal comfort is through selectivity of information. An individual will usually pull the support personally needed to cope from the environment if sufficient resources are available. However, information provided young cancer patients is often filtered through the physicians and parents perspectives of the patient's needs without systematic input from the patient. In order to ensure that adequate information resources are available to help teenage patients cope with their illness, health professionals must have insights into the information needs of those patients. No previous efforts to address this subject were found in the literature.^ This study was designed to identify adolescent perspectives of their disease-related information needs and to compare their viewpoints with those of their parents and physicians. Sixty-five outpatient cancer patients (ages 11-20) receiving treatment at the University of Texas M. D. Anderson Hospital and Tumor Institute in Houston, Texas, 60 of their parents, and 53 physicians, who were involved in the treatment of pediatric patients at M. D. Anderson, were asked to complete self-administered questionnaires. The questionnaires used were developed, administered and analyzed by the investigator. Specific areas addressed in the questionnaires included: Perceptions of cancer-related tests and treatments, the importance of 30 disease-related items of information, responses evoked by receipt of information, current and preferred sources of information, delivery of information at the time of diagnosis, and disease-related information requested for patients, family, friends and teachers.^ Adolescent perceptions of their information needs and their preferences for delivery of information were determined. The relationships between patient-parent and patient-physician perceptions were then analyzed to determine areas in which agreements and disparities in viewpoint existed. Programmatic and research recommendations were then provided.^ Hopefully, through these efforts, the adolescent patient will be helped to receive relevant information support from those deemed to be most important to his/her efforts to cope with cancer. ^

NOVEL PHANTOMS AND POST-PROCESSING FOR DIFFUSION SPECTRUM IMAGING

High Angular Resolution Diffusion Imaging (HARDI) techniques, including Diffusion Spectrum Imaging (DSI), have been proposed to resolve crossing and other complex fiber architecture in the human brain white matter. In these methods, directional information of diffusion is inferred from the peaks in the orientation distribution function (ODF). Extensive studies using histology on macaque brain, cat cerebellum, rat hippocampus and optic tracts, and bovine tongue are qualitatively in agreement with the DSI-derived ODFs and tractography. However, there are only two studies in the literature which validated the DSI results using physical phantoms and both these studies were not performed on a clinical MRI scanner. Also, the limited studies which optimized DSI in a clinical setting, did not involve a comparison against physical phantoms. Finally, there is lack of consensus on the necessary pre- and post-processing steps in DSI; and ground truth diffusion fiber phantoms are not yet standardized. Therefore, the aims of this dissertation were to design and construct novel diffusion phantoms, employ post-processing techniques in order to systematically validate and optimize (DSI)-derived fiber ODFs in the crossing regions on a clinical 3T MR scanner, and develop user-friendly software for DSI data reconstruction and analysis. Phantoms with a fixed crossing fiber configuration of two crossing fibers at 90° and 45° respectively along with a phantom with three crossing fibers at 60°, using novel hollow plastic capillaries and novel placeholders, were constructed. T2-weighted MRI results on these phantoms demonstrated high SNR, homogeneous signal, and absence of air bubbles. Also, a technique to deconvolve the response function of an individual peak from the overall ODF was implemented, in addition to other DSI post-processing steps. This technique greatly improved the angular resolution of the otherwise unresolvable peaks in a crossing fiber ODF. The effects of DSI acquisition parameters and SNR on the resultant angular accuracy of DSI on the clinical scanner were studied and quantified using the developed phantoms. With a high angular direction sampling and reasonable levels of SNR, quantification of a crossing region in the 90°, 45° and 60° phantoms resulted in a successful detection of angular information with mean ± SD of 86.93°±2.65°, 44.61°±1.6° and 60.03°±2.21° respectively, while simultaneously enhancing the ODFs in regions containing single fibers. For the applicability of these validated methodologies in DSI, improvement in ODFs and fiber tracking from known crossing fiber regions in normal human subjects were demonstrated; and an in-house software package in MATLAB which streamlines the data reconstruction and post-processing for DSI, with easy to use graphical user interface was developed. In conclusion, the phantoms developed in this dissertation offer a means of providing ground truth for validation of reconstruction and tractography algorithms of various diffusion models (including DSI). Also, the deconvolution methodology (when applied as an additional DSI post-processing step) significantly improved the angular accuracy of the ODFs obtained from DSI, and should be applicable to ODFs obtained from the other high angular resolution diffusion imaging techniques.

A Model-Based Monitoring Architecture for Heterogeneous Enterprise Services and Information Systems

Runtime management of distributed information systems is a complex and costly activity. One of the main challenges that must be addressed is obtaining a complete and updated view of all the managed runtime resources. This article presents a monitoring architecture for heterogeneous and distributed information systems. It is composed of two elements: an information model and an agent infrastructure. The model negates the complexity and variability of these systems and enables the abstraction over non-relevant details. The infrastructure uses this information model to monitor and manage the modeled environment, performing and detecting changes in execution time. The agents infrastructure is further detailed and its components and the relationships between them are explained. Moreover, the proposal is validated through a set of agents that instrument the JEE Glassfish application server, paying special attention to support distributed configuration scenarios.

Quantitative Determination of the Relationship between Internal Validity and Bias in Software Engineering Experiments: Consequences for Systematic Literature Reviews

Quality assessment is one of the activities performed as part of systematic literature reviews. It is commonly accepted that a good quality experiment is bias free. Bias is considered to be related to internal validity (e.g., how adequately the experiment is planned, executed and analysed). Quality assessment is usually conducted using checklists and quality scales. It has not yet been proven;however, that quality is related to experimental bias. Aim: Identify whether there is a relationship between internal validity and bias in software engineering experiments. Method: We built a quality scale to determine the quality of the studies, which we applied to 28 experiments included in two systematic literature reviews. We proposed an objective indicator of experimental bias, which we applied to the same 28 experiments. Finally, we analysed the correlations between the quality scores and the proposed measure of bias. Results: We failed to find a relationship between the global quality score (resulting from the quality scale) and bias; however, we did identify interesting correlations between bias and some particular aspects of internal validity measured by the instrument. Conclusions: There is an empirically provable relationship between internal validity and bias. It is feasible to apply quality assessment in systematic literature reviews, subject to limits on the internal validity aspects for consideration.

Liquid lead and Lithium. A Comprehensive molecular dynamics study

Pb17Li is today a reference breeder material in diverse fusion R&D programs worldwide. One of the main issues in these programs is the problem of liquid metals breeder blanket behavior. Structural material of the blanket should meet high requirements because of extreme operating conditions. Therefore the knowledge of eutectic properties like optimal composition, physical and thermodynamic behavior or diffusion coefficients of Tritium are extremely necessary for current designs. In particular, the knowledge of the function linking the tritium concentration dissolved in liquid materials with the tritium partial pressure at a liquid/gas interface in equilibrium, CT=f(PT), is of basic importance because it directly impacts all functional properties of a blanket determining: tritium inventory, tritium permeation rate and tritium extraction efficiency. Nowadays, understanding the structure and behavior of this compound is a real goal in fusion engineering and materials science. Simulations of liquids can provide much information to the community; not only supplementing experimental data, but providing new tests of theories and ideas, making specific predictions that require experimental tests, and ultimately helping to lead to the deeper understanding and better predictive behavior.

Generic competences in engineering field: a comparative study between Latin America and European Union

In this work, a comparison between the competences codes in the CDIÓs* curriculum, the ones defined for the Tunning Project and the International Project Management Association (IPMA) is made. The goal is to define the most appropriate competences codes for the engineering education in Latin America. The CDIO code is obtained from the engineering practice, and responds to the Accreditation Board for Engineering and Technology (ABET) standards of accreditation. The Tuning competences are the ones defined for Latin America and the IPMÁs are international competences for project management. It is the first time that the competences defined in ABET accreditation standards in the engineering field are compared with the international competences according to IPMÁs model. The results give evidence that, in first place, there is a need to apply holistic models in the definition of an engineering curriculum. Second, the pertinence of these models in the definition of engineering programs in Latin America.

Desarrollo de una GUI para el estudio de Sistemas de Comunicaciones Ópticas

El peso específico de las Comunicaciones Ópticas dentro del ámbito de la Ingeniería de Telecomunicación no cesa de crecer. Sus aplicaciones, inicialmente dedicadas a las grandes líneas que enlazan las centrales de conmutación, alcanzan en la actualidad, como se ha mencionado, hasta los mismos hogares. Los progresos en este campo, con una sucesión sin tregua, no sólo se destinan a incrementar la capacidad de transmisión de los sistemas, sino a ampliar la diversidad de los procesos que sobre las señales se efectúan en el dominio óptico. Este dinamismo demanda a los profesionales del sector una revisión y actualización de sus conocimientos que les permitan resolver con soltura las cuestiones de su actividad de ingeniería. Por otra parte, durante los últimos años la importancia de las Comunicaciones Ópticas también se ha reflejado en las diferentes titulaciones de Ingenierías de Telecomunicación, cuyos planes de estudio contemplan esta materia tanto en asignaturas troncales como optativas. A menudo, las fuentes de información disponibles abordan esta disciplina con una orientación principalmente teórica. Profesionales y estudiantes de Ingeniería, pues, frente a esta materia se encuentran unos temas que tratan fenómenos físicos complejos, abundantes en conceptos abstractos y con un florido aparato matemático, pero muchas veces carentes de una visión práctica, importantísima en ingeniería, y que es, en definitiva, lo que se exige a alumnos e ingenieros: saber resolver problemas y cuestiones relacionados con las Comunicaciones Ópticas. Los sistemas de comunicaciones ópticas, y en especial aquellos que utilizan la fibra óptica como medio para la transmisión de información, como se ha dicho, están alcanzando un desarrollo importante en el campo de las telecomunicaciones. Las bondades que ofrece la fibra, de sobra conocidos y mencionados en el apartado que antecede (gran ancho de banda, inmunidad total a las perturbaciones de origen electromagnético, así como la no producción de interferencias, baja atenuación, etc.), han hecho que, hoy en día, sea uno de los campos de las llamadas tecnologías de la información y la comunicación que presente mayor interés por parte de científicos, ingenieros, operadores de telecomunicaciones y, por supuesto, usuarios. Ante esta realidad, el objetivo y justificación de la realización de este proyecto, por tanto, no es otro que el de acercar esta tecnología al futuro ingeniero de telecomunicaciones, y/o a cualquier persona con un mínimo de interés en este tema, y mostrarle de una forma práctica y visual los diferentes fenómenos que tienen lugar en la transmisión de información por medio de fibra óptica, así como los diferentes bloques y dispositivos en que se divide dicha comunicación. Para conseguir tal objetivo, el proyecto fin de carrera aquí presentado tiene como misión el desarrollo de una interfaz gráfica de usuario (GUI, del inglés Graphic User Interface) que permita a aquel que la utilice configurar de manera sencilla cada uno de los bloques en que se compone un enlace punto a punto de fibra óptica. Cada bloque en que se divide este enlace estará compuesto por varias opciones, que al elegir y configurar como se quiera, hará variar el comportamiento del sistema y presentará al usuario los diferentes fenómenos presentes en un sistema de comunicaciones ópticas, como son el ruido, la dispersión, la atenuación, etc., para una mejor comprensión e interiorización de la teoría estudiada. Por tanto, la aplicación, implementada en MATLAB, fruto de la realización de este PFC pretende servir de complemento práctico para las asignaturas dedicadas al estudio de las comunicaciones ópticas a estudiantes en un entorno amigable e intuitivo. Optical Communications in the field of Telecommunications Engineering continues to grow. Its applications, initially dedicated to large central lines that link the switching currently achieved, as mentioned, to the same household nowadays. Progress in this field, with a relentless succession, not only destined to increase the transmission capacity of the systems, but to broaden the diversity of the processes that are performed on the signals in the optical domain. This demands to professionals reviewing and updating their skills to enable them resolve issues easily. Moreover, in recent years the importance of optical communications is also reflected in the different degrees of Telecommunications Engineering, whose curriculum contemplates this area. Often, the information sources available to tackle this discipline mainly theoretical orientation. Engineering professionals and students are faced this matter are few topics discussing complex physical phenomena, and abstract concepts abundant with a flowery mathematical apparatus, but often wotput a practical, important in engineering, and that is what is required of students and engineers: knowing how to solve problems and issues related to optical communications. Optical communications systems, particularly those using optical fiber as a medium for transmission of information, as stated, are reaching a significant development in the field of telecommunications. The advantages offered by the fiber, well known and referred to in the preceding paragraph (high bandwidth, immunity to electromagnetic disturbances of origin and production of non interference, low attenuation, etc..), have made today, is one of the fields of information and communication technology that this increased interest by scientists, engineers, telecommunications operators and, of course, users. Given this reality, the purpose and justification of this project is not other than to bring this technology to the future telecommunications engineer, and / or anyone with a passing interest in this subject, and showing of a practical and various visual phenomena occurring in the transmission of information by optical fiber, as well as different blocks and devices in which said communication is divided. To achieve that objective, the final project presented here has as its mission the development of a graphical user interface (GUI) that allows the user to configure each of the blocks in which divided a point-to-point optical fiber. Each block into which this link will consist of several options to choose and configure it as you like, this will change the behavior of the system and will present to the user with the different phenomena occurring in an optical communication system, such as noise, dispersion, attenuation, etc., for better understanding and internalization of the theory studied. Therefore, the application, implemented in MATLAB, the result of the completion of the thesis is intended to complement practical subjects for the study of optical communications students in a friendly and intuitive environment.

Integration of design tools and knowledge capture into a CAD system: a case study

onceptual design phase is partially supported by product lifecycle management/computer-aided design (PLM/CAD) systems causing discontinuity of the design information flow: customer needs — functional requirements — key characteristics — design parameters (DPs) — geometric DPs. Aiming to address this issue, it is proposed a knowledge-based approach is proposed to integrate quality function deployment, failure mode and effects analysis, and axiomatic design into a commercial PLM/CAD system. A case study, main subject of this article, was carried out to validate the proposed process, to evaluate, by a pilot development, how the commercial PLM/CAD modules and application programming interface could support the information flow, and based on the pilot scheme results to propose a full development framework.

Rapid prototyping for biomedical engineering: current capabilities and Challenges

A new set of manufacturing technologies has emerged in the past decades to address market requirements in a customized way and to provide support for research tasks that require prototypes. These new techniques and technologies are usually referred to as rapid prototyping and manufacturing technologies, and they allow prototypes to be produced in a wide range of materials with remarkable precision in a couple of hours. Although they have been rapidly incorporated into product development methodologies, they are still under development, and their applications in bioengineering are continuously evolving. Rapid prototyping and manufacturing technologies can be of assistance in every stage of the development process of novel biodevices, to address various problems that can arise in the devices' interactions with biological systems and the fact that the design decisions must be tested carefully. This review focuses on the main fields of application for rapid prototyping in biomedical engineering and health sciences, as well as on the most remarkable challenges and research trends.

Activity based costing, time-driven activity based costing and lean accounting: differences among three accounting systems' approach to manufacturing

Choosing an appropriate accounting system for manufacturing has always been a challenge for managers. In this article we try to compare three accounting systems designed since 1980 to address problems of traditional accounting system. In the first place we are going to present a short overview on background and definition of three accounting systems: Activity Based costing, Time-Driven Activity Based Costing and Lean Accounting. Comparisons are made based on the three basic roles of information generated by accounting systems: financial reporting, decision making, and operational control and improvement. The analysis in this paper reveals how decisions are made over the value stream in the companies using Lean Accounting while decisions under the ABC Accounting system are taken at individual product level, and finally we will show how TD-ABC covers both product and process levels for decision making. In addition, this paper shows the importance of nonfinancial measures for operational control and improvement under the Lean Accounting and TD-ABC methods whereas ABC relies mostly on financial measures in this context.