Design of a goal ontology for medical decision-support

Thesis (S.M.)--Harvard-MIT Division of Health Sciences and Technology, 2005.Includes bibliographical references (leaves 34-36).Objectives: There are several ongoing efforts aimed at developing formal models of medical knowledge and reasoning to design decision-support systems. Until now, these efforts have focused primarily on representing content of clinical guidelines and their logical structure. The present study aims to develop a computable representation of health-care providers' intentions to be used as part of a framework for implementing clinical decision-support systems. Our goal is to create an ontology that supports retrieval of plans based on the intentions or goals of the clinician. Methods: We developed an ontological representation of medical goals, plans, clinical scenarios and other relevant entities in medical decision-making. We used the resulting ontology along with an external ontology inference engine to simulate selection of clinical recommendations based on goals. The ontology instances used in the simulation were modeled from two clinical guidelines. Testing the design: Thirty-two clinical recommendations were encoded in the experimental model. Nine test cases were created to verify the ability of the model to retrieve the plans. For all nine cases, plans were successfully retrieved. Conclusion: The ontological design we developed supported effective reasoning over a medical knowledge base.(cont.) The immediate extension of this approach to be fully developed in medical applications may be partially limited by the lack of available editing tools. Many efforts in this area are currently aiming to the development of needed technologies.by Davide Zacacagnini [i.e. Zaccagnini].S.M

Performance study of a thin film cation exchange membrane on carbon electrode for supercapacitor application

In this work we report a green procedure for the infiltration of a SPEEK solution into a porous carbon electrode resulting in a thin-film cation exchange membrane. The electrodes have been investigated by a morphological point of view, showing the formation of a thin coating infiltrated into the porous carbonaceous matrix, while mechanical peeling of a tape demonstrated the adhesion of the proposed layer. The fabricated electrodes have been analyzed by electrochemical measurement. The 3-electrode cyclic voltammetry measurements allowed to verify the voltage window resulting in an improved negative potential, while the electrochemical impedance spectroscopy showed a reduction of the electrical resistance. The SPEEK electrode was used in a supercapacitor and deeply characterized by electrochemical analysis. The reported findings demonstrate for the first time the possibility to exploit a cation exchange material in thin film configuration for supercapacitor application with improved performance of the device and exclusively involving the use of nontoxic reagents

Advancing translational research with the Semantic Web

<p>Abstract</p> <p>Background</p> <p>A fundamental goal of the U.S. National Institute of Health (NIH) "Roadmap" is to strengthen <it>Translational Research</it>, defined as the movement of discoveries in basic research to application at the clinical level. A significant barrier to translational research is the lack of uniformly structured data across related biomedical domains. The Semantic Web is an extension of the current Web that enables navigation and meaningful use of digital resources by automatic processes. It is based on common formats that support aggregation and integration of data drawn from diverse sources. A variety of technologies have been built on this foundation that, together, support identifying, representing, and reasoning across a wide range of biomedical data. The Semantic Web Health Care and Life Sciences Interest Group (HCLSIG), set up within the framework of the World Wide Web Consortium, was launched to explore the application of these technologies in a variety of areas. Subgroups focus on making biomedical data available in RDF, working with biomedical ontologies, prototyping clinical decision support systems, working on drug safety and efficacy communication, and supporting disease researchers navigating and annotating the large amount of potentially relevant literature.</p> <p>Results</p> <p>We present a scenario that shows the value of the information environment the Semantic Web can support for aiding neuroscience researchers. We then report on several projects by members of the HCLSIG, in the process illustrating the range of Semantic Web technologies that have applications in areas of biomedicine.</p> <p>Conclusion</p> <p>Semantic Web technologies present both promise and challenges. Current tools and standards are already adequate to implement components of the bench-to-bedside vision. On the other hand, these technologies are young. Gaps in standards and implementations still exist and adoption is limited by typical problems with early technology, such as the need for a critical mass of practitioners and installed base, and growing pains as the technology is scaled up. Still, the potential of interoperable knowledge sources for biomedicine, at the scale of the World Wide Web, merits continued work.</p

Recording the ethical provenance of data and automating data stewardship

Health organisations use numerous different mechanisms to collect biomedical data, to determine the applicable ethical, legal and institutional conditions of use, and to reutilise the data in accordance with the relevant rules. These methods and mechanisms differ from one organisation to another, and involve considerable specialised human labour, including record-keeping functions and decision-making committees. In reutilising data at scale, however, organisations struggle to meet demands for data interoperability and for rapid inter-organisational data exchange due to reliance on legacy paper-based records and on the human-initiated administration of accompanying permissions in data. The adoption of permissions-recording, and permissions-administration tools that can be implemented at scale across numerous organisations is imperative. Further, these must be implemented in a manner that does not compromise the nuanced and contextual adjudicative processes of research ethics committees, data access committees, and biomedical research organisations. The tools required to implement a streamlined system of biomedical data exchange have in great part been developed. Indeed, there remains but a small core of functions that must further be standardised and automated to enable the recording and administration of permissions in biomedical research data with minimal human effort. Recording ethical provenance in this manner would enable biomedical data exchange to be performed at scale, in full respect of the ethical, legal, and institutional rules applicable to different datasets. This despite foundational differences between the distinct legal and normative frameworks is applicable to distinct communities and organisations that share data between one another

Overexpression of miR-210 and its significance in ischemic tissue damage

Hypoxia-induced miR-210 displays a pro-survival, cytoprotective and pro-angiogenic role in several in vitro systems. In vivo, we previously found that miR-210 inhibition increases ischemic damage. Here we describe the generation of a versatile transgenic mouse model allowing the evaluation of miR-210 therapeutic potential in ischemic cardiovascular diseases. We generated a Tet-On miR-210 transgenic mouse strain (TG-210) by targeted transgenesis in the ROSA26 locus. To functionally validate miR-210 transgenic mice, hindlimb ischemia was induced by femoral artery dissection. Blood perfusion was evaluated by power Doppler while tissue damage and inflammation were assessed by histological evaluation. We found that miR-210 levels were rapidly increased in TG-210 mice upon doxycycline administration. miR-210 overexpression was maintained over time and remained within physiological levels in multiple tissues. When hindlimb ischemia was induced, miR-210 overexpression protected from both muscular and vascular ischemic damage, decreased inflammatory cells density and allowed to maintain a better calf perfusion. In conclusion, we generated and functionally validated a miR-210 transgenic mouse model. Albeit validated in the context of a specific cardiovascular ischemic disease, miR-210 transgenic mice may also represent a useful model to assess the function of miR-210 in other physio-pathological conditions

Enhancing the performance and mechanical stability of 2D-based hybrid micro-supercapacitors using dendritic-gold as framework layer

In recent years scaling-down approaches on supercapacitors has led to the definition of Micro-Supercapacitors (μSC). The demand for these devices is increasing for many applications in microelectronics, such as wearable energy storage and self-powered sensors. Recently, many efforts have been made to achieve good results in terms of power and energy densities. However, the current research challenge is to develop a sustainable chain production, involving eco-friendly materials, such as water-based electrolytes, organic binders and low-impact active material. This work presents a hybrid μSC using low impact materials and a fully water-based solution. Different approaches were adopted for patterning the current collectors and for the deposition of the active materials. The material chosen as anode was MnO2 deposited by electroplating, which presents pseudocapacitive behavior. The active material used for the cathode was Activated Carbon (AC), deposited by drop-casting, which works through the electric double layer (EDL) capacitance effect. The electrolyte was 1 M Na2SO4 in water. We investigated the addition of an interlayer micro-structure made of Dendritic-Gold (D-Gold). The results show that such a layer seems to have positive effects in terms of wettability and mechanical stability, enhancing the adhesion of the active material. Electron microscopy measurement shows the characteristic tree-like shape of the layer. The device reports a capacitance of about 14 to 23 mF cm-2 and a large voltage window equal to 1.6 V. The present research explores, for the first time, the effects of dendritic gold in planar electrochemical capacitors. The findings should give an important contribution for boost energy storage densities in the field of 2D micro-supercapacitors