SSME lifetime prediction and verification, integrating environments, structures, materials: The challenge

NASA Technical Reports Server (NTRS)

Ryan, R. S.; Salter, L. D.; Young, G. M., III; Munafo, P. M.

1985-01-01

The planned missions for the space shuttle dictated a unique and technology-extending rocket engine. The high specific impulse requirements in conjunction with a 55-mission lifetime, plus volume and weight constraints, produced unique structural design, manufacturing, and verification requirements. Operations from Earth to orbit produce severe dynamic environments, which couple with the extreme pressure and thermal environments associated with the high performance, creating large low cycle loads and high alternating stresses above endurance limit which result in high sensitivity to alternating stresses. Combining all of these effects resulted in the requirements for exotic materials, which are more susceptible to manufacturing problems, and the use of an all-welded structure. The challenge of integrating environments, dynamics, structures, and materials into a verified SSME structure is discussed. The verification program and developmental flight results are included. The first six shuttle flights had engine performance as predicted with no failures. The engine system has met the basic design challenges.

Design and Implementation of Therapist Online Counseling

ERIC Educational Resources Information Center

Thomas, Aaron O.; Lee, Geoff; Ess, Brian

2015-01-01

The following paper describes the rationale for creating an online therapy program of cognitive behavioral therapy, or CBT, for students at the University of Florida who are struggling with stress and anxiety. In addition, the paper discusses the unique challenges of the instructional design process of creating psychoeducational materials through…

Design and high-volume manufacture of low-cost molded IR aspheres for personal thermal imaging devices

NASA Astrophysics Data System (ADS)

Zelazny, A. L.; Walsh, K. F.; Deegan, J. P.; Bundschuh, B.; Patton, E. K.

2015-05-01

The demand for infrared optical elements, particularly those made of chalcogenide materials, is rapidly increasing as thermal imaging becomes affordable to the consumer. The use of these materials in conjunction with established lens manufacturing techniques presents unique challenges relative to the cost sensitive nature of this new market. We explore the process from design to manufacture, and discuss the technical challenges involved. Additionally, facets of the development process including manufacturing logistics, packaging, supply chain management, and qualification are discussed.

Promoting Collaborative Problem-Solving Skills in a Course on Engineering Grand Challenges

ERIC Educational Resources Information Center

Zou, Tracy X. P.; Mickleborough, Neil C.

2015-01-01

The ability to solve problems with people of diverse backgrounds is essential for engineering graduates. A course on engineering grand challenges was designed to promote collaborative problem-solving (CPS) skills. One unique component is that students need to work both within their own team and collaborate with the other team to tackle engineering…

Creating a Transformational Learning Experience: Immersing Students in an Intensive Interdisciplinary Learning Environment

ERIC Educational Resources Information Center

White, Shelley K.; Nitkin, Mindell Reiss

2014-01-01

The Simmons World Challenge is a unique, interdisciplinary program recently developed at Simmons College. It immerses students in an intensive winter-session course that challenges them to tackle a pressing social issue, such as poverty or hunger, and create actionable solutions to the problem. The program was conceived and designed to harness the…

Identifying Unique Ethical Challenges of Indigenous Field-Workers: A Commentary on Alexander and Richman's "Ethical Dilemmas in Evaluations Using Indigenous Research Workers"

ERIC Educational Resources Information Center

Smith, Nick L.

2008-01-01

In contrast with nonindigenous workers, to what extent do unique ethical problems arise when indigenous field-workers participate in field studies? Three aspects of study design and operation are considered: data integrity issues, risk issues, and protection issues. Although many of the data quality issues that arise with the use of indigenous…

Studios Abroad: A Challenge in Innovative Pedagogy

ERIC Educational Resources Information Center

Macedo, Joseli

2017-01-01

Study abroad programs offer a unique opportunity to evaluate pedagogic models. The role of studios in design and planning pedagogy has been examined. However, how the general framework of a studio supports other pedagogic models has not been widely discussed. This article assesses a series of urban planning and design studios conducted abroad to…

Designing a Bridging Discourse: Re-Mediation of a Mathematical Learning Disability

ERIC Educational Resources Information Center

Lewis, Katherine E.

2017-01-01

Students with disabilities present a unique instructional design challenge. These students often have qualitatively different ways of processing information, meaning that standard instructional approaches may not be effective. In this study I present a case study of a student with a mathematical learning disability for whom standard instruction on…

Covalent Organic Frameworks: From Materials Design to Biomedical Application

PubMed Central

Zhao, Fuli; Liu, Huiming; Mathe, Salva D. R.; Dong, Anjie

2017-01-01

Covalent organic frameworks (COFs) are newly emerged crystalline porous polymers with well-defined skeletons and nanopores mainly consisted of light-weight elements (H, B, C, N and O) linked by dynamic covalent bonds. Compared with conventional materials, COFs possess some unique and attractive features, such as large surface area, pre-designable pore geometry, excellent crystallinity, inherent adaptability and high flexibility in structural and functional design, thus exhibiting great potential for various applications. Especially, their large surface area and tunable porosity and π conjugation with unique photoelectric properties will enable COFs to serve as a promising platform for drug delivery, bioimaging, biosensing and theranostic applications. In this review, we trace the evolution of COFs in terms of linkages and highlight the important issues on synthetic method, structural design, morphological control and functionalization. And then we summarize the recent advances of COFs in the biomedical and pharmaceutical sectors and conclude with a discussion of the challenges and opportunities of COFs for biomedical purposes. Although currently still at its infancy stage, COFs as an innovative source have paved a new way to meet future challenges in human healthcare and disease theranostic. PMID:29283423

The Laparosound{trade mark, serif}-an ultrasonic morcellator for use in laparoscopic surgery

NASA Astrophysics Data System (ADS)

Malinowski, Igor; Łobodzinski, Suave S.; Paśniczek, Roman

2012-05-01

The laparoscopic surgery has gained presence in the operating room in cases where it is feasible to spare patient trauma and minimize the hospital stay. One unique challenge in laparoscopic/endoscopic surgery is operating and removing tissue volume through keyhole - trocar. The removal of tissues by fragmentation is generally termed morcellation. We proposed a new method for soft tissue morcellation using laparoscopy. A unique ultrasonic laparoscopic surgical device, termed Laparosound{trade mark, serif}, utilizing laparoscopic high amplitude ultrasonic waveguides, operating in edge mode, has been developed that uses the principle of ultrasonic cavitation phenomenon for excision and morcellation of a variety of tissue types. The local ultrasonic acoustic intensity at the distal waveguide tip is sufficiently high that the liquefaction of moist tissue occurs. The mechanism of tissue morcellation is deemed to be cavitation based, therefore is dependant on water content in tissue, and thus its effectiveness depends on tissue type. This results in ultrasound being efficient in moist tissue and sparing dry, collagen rich blood vessels and thus minimizes bleeding. The applications of such device in particular, commonly encountered, could lay in general and ob/gyn laparoscopic surgery, whereas other applications could emerge. The design of power ultrasonic instruments for mass clinical applications poses however unique challenges, such as ability to design and build ultrasonic resonators that last in conditions of ultrasonic fatigue. These highly non-linear devices, whose behavior is hard to predict, have become the challenge of the author of the present paper. The object of work is to design and build an operating device capable of ultrasonic soft tissue morcellation in laparoscopic surgery. This includes heavy computational ultrasonics verified by testing and manufacturing feasibility using titanium biomedical alloys. The prototype Laparosound{trade mark, serif} device has been built and tested. Some of the challenges in design and development of Laparosound{trade mark, serif} ultrasonic laparoscopic morcellator have been presented.

Challenges of Applying a Comprehensive Model of Intervention Fidelity

PubMed Central

Bosak, Kelly; Pozehl, Bunny; Yates, Bernice

2014-01-01

Applying a comprehensive model of fidelity to interventions delivered by Information and Communication Technology (ICT) has multiple challenges. Fidelity must be considered in the design, implementation, evaluation, and reporting of the intervention. The fidelity strategies must address the unique aspects of the technology, including training providers to instruct participants to use the technology and to provide standardized feedback, rather than deliver the intervention in-person. Other challenges include the nonspecific effects resulting from participants accessing unintended content in interventions delivered by the Internet. ICT allows participant receipt and enactment of intervention skills to be assessed by electronic evidence, rather than in-person observation. Interventions using ICT, such as the Internet are unique, and there is less control of participant interaction with various electronic components. Monitoring participant use and providing standardized feedback for receipt and enactment of intervention skills is key to ensuring intervention fidelity. The final challenges involve evaluating and reporting fidelity. PMID:21474676

Linear Proof Mass Actuator

NASA Technical Reports Server (NTRS)

Holloway, Sidney E., III

1994-01-01

This paper describes the mechanical design, analysis, fabrication, testing, and lessons learned by developing a uniquely designed spaceflight-like actuator. The linear proof mass actuator (LPMA) was designed to attach to both a large space structure and a ground test model without modification. Previous designs lacked the power to perform in a terrestrial environment while other designs failed to produce the desired accelerations or frequency range for spaceflight applications. Thus, the design for a unique actuator was conceived and developed at NASA Langley Research Center. The basic design consists of four large mechanical parts (mass, upper housing, lower housing, and center support) and numerous smaller supporting components including an accelerometer, encoder, and four drive motors. Fabrication personnel were included early in the design phase of the LPMA as part of an integrated manufacturing process to alleviate potential difficulties in machining an already challenging design. Operating testing of the LPMA demonstrated that the actuator is capable of various types of load functions.

Linear Proof Mass Actuator

NASA Technical Reports Server (NTRS)

Holloway, S. E., III

1995-01-01

This paper describes the mechanical design, analysis, fabrication, testing, and lessons learned by developing a uniquely designed spaceflight-like actuator. The Linear Proof Mass Actuator (LPMA) was designed to attach to both a large space structure and a ground test model without modification. Previous designs lacked the power to perform in a terrestrial environment while other designs failed to produce the desired accelerations or frequency range for spaceflight applications. Thus, the design for a unique actuator was conceived and developed at NASA Langley Research Center. The basic design consists of four large mechanical parts (Mass, Upper Housing, Lower Housing, and Center Support) and numerous smaller supporting components including an accelerometer, encoder, and four drive motors. Fabrication personnel were included early in the design phase of the LPMA as part of an integrated manufacturing process to alleviate potential difficulties in machining an already challenging design. Operational testing of the LPMA demonstrated that the actuator is capable of various types of load functions.

Human Factors in Streaming Data Analysis: Challenges and Opportunities for Information Visualization

DOE Office of Scientific and Technical Information (OSTI.GOV)

Dasgupta, Aritra; Arendt, Dustin L.; Franklin, Lyndsey

State-of-the-art visual analytics models and frameworks mostly assume a static snapshot of the data, while in many cases it is a stream with constant updates and changes. Exploration of streaming data poses unique challenges as machine-level computations and abstractions need to be synchronized with the visual representation of the data and the temporally evolving human insights. In the visual analytics literature, we lack a thorough characterization of streaming data and analysis of the challenges associated with task abstraction, visualization design, and adaptation of the role of human-in-the-loop for exploration of data streams. We aim to fill this gap by conductingmore » a survey of the state-of-the-art in visual analytics of streaming data for systematically describing the contributions and shortcomings of current techniques and analyzing the research gaps that need to be addressed in the future. Our contributions are: i) problem characterization for identifying challenges that are unique to streaming data analysis tasks, ii) a survey and analysis of the state-of-the-art in streaming data visualization research with a focus on the visualization design space for dynamic data and the role of the human-in-the-loop, and iii) reflections on the design-trade-offs for streaming visual analytics techniques and their practical applicability in real-world application scenarios.« less

Mars Science Laboratory Drill

NASA Technical Reports Server (NTRS)

Okon, Avi B.

2010-01-01

The Drill for the Mars Science Laboratory mission is a rotary-percussive sample acquisition device with an emphasis on toughness and robustness to handle the harsh environment on Mars. The unique challenges associated with autonomous drilling from a mobile robot are addressed. A highly compressed development schedule dictated a modular design architecture that satisfies the functional and load requirements while allowing independent development and testing of the Drill subassemblies. The Drill consists of four actuated mechanisms: a spindle that rotates the bit, a chuck that releases and engages bits, a novel voice-coil-based percussion mechanism that hammers the bit, and a linear translation mechanism. The Drill has three passive mechanisms: a replaceable bit assembly that acquires and collects sample, a contact sensor / stabilizer mechanism, and, lastly a flex harness service loop. This paper describes the various mechanisms that makeup the Drill and discusses the solutions to their unique design and development challenges.

Multidisciplinary Optimization of a Transport Aircraft Wing using Particle Swarm Optimization

NASA Technical Reports Server (NTRS)

Sobieszczanski-Sobieski, Jaroslaw; Venter, Gerhard

2002-01-01

The purpose of this paper is to demonstrate the application of particle swarm optimization to a realistic multidisciplinary optimization test problem. The paper's new contributions to multidisciplinary optimization is the application of a new algorithm for dealing with the unique challenges associated with multidisciplinary optimization problems, and recommendations as to the utility of the algorithm in future multidisciplinary optimization applications. The selected example is a bi-level optimization problem that demonstrates severe numerical noise and has a combination of continuous and truly discrete design variables. The use of traditional gradient-based optimization algorithms is thus not practical. The numerical results presented indicate that the particle swarm optimization algorithm is able to reliably find the optimum design for the problem presented here. The algorithm is capable of dealing with the unique challenges posed by multidisciplinary optimization as well as the numerical noise and truly discrete variables present in the current example problem.

FSW of Aluminum Tailor Welded Blanks across Machine Platforms

DOE Office of Scientific and Technical Information (OSTI.GOV)

Hovanski, Yuri; Upadhyay, Piyush; Carlson, Blair

2015-02-16

Development and characterization of friction stir welded aluminum tailor welded blanks was successfully carried out on three separate machine platforms. Each was a commercially available, gantry style, multi-axis machine designed specifically for friction stir welding. Weld parameters were developed to support high volume production of dissimilar thickness aluminum tailor welded blanks at speeds of 3 m/min and greater. Parameters originally developed on an ultra-high stiffness servo driven machine where first transferred to a high stiffness servo-hydraulic friction stir welding machine, and subsequently transferred to a purpose built machine designed to accommodate thin sheet aluminum welding. The inherent beam stiffness, bearingmore » compliance, and control system for each machine were distinctly unique, which posed specific challenges in transferring welding parameters across machine platforms. This work documents the challenges imposed by successfully transferring weld parameters from machine to machine, produced from different manufacturers and with unique control systems and interfaces.« less

Challenges and models in supporting logistics system design for dedicated-biomass-based bioenergy industry.

PubMed

Zhu, Xiaoyan; Li, Xueping; Yao, Qingzhu; Chen, Yuerong

2011-01-01

This paper analyzed the uniqueness and challenges in designing the logistics system for dedicated biomass-to-bioenergy industry, which differs from the other industries, due to the unique features of dedicated biomass (e.g., switchgrass) including its low bulk density, restrictions on harvesting season and frequency, content variation with time and circumambient conditions, weather effects, scattered distribution over a wide geographical area, and so on. To design it, this paper proposed a mixed integer linear programming model. It covered from planting and harvesting switchgrass to delivering to a biorefinery and included the residue handling, concentrating on integrating strategic decisions on the supply chain design and tactical decisions on the annual operation schedules. The present numerical examples verified the model and demonstrated its use in practice. This paper showed that the operations of the logistics system were significantly different for harvesting and non-harvesting seasons, and that under the well-designed biomass logistics system, the mass production with a steady and sufficient supply of biomass can increase the unit profit of bioenergy. The analytical model and practical methodology proposed in this paper will help realize the commercial production in biomass-to-bioenergy industry. Copyright © 2010 Elsevier Ltd. All rights reserved.

CBPR with service providers: arguing a case for engaging practitioners in all phases of research.

PubMed

Spector, Anya Y

2012-03-01

This review synthesizes the literature on CBPR with service providers to identify the benefits to, unique contributions of, and challenges experienced by professional service providers engaged in collaborative research. Service providers benefited by obtaining research-based knowledge to help the communities they serve, gaining research skills, professional relationships, professional development, and new programs. They contributed by informing research aims, designing interventions, conducting recruitment, informing overall study design, and dissemination. Challenges include time, resources, organizational factors, and disconnects between researchers and service providers. Policy and practice implications are explored.

Can the impact on health of a government policy designed to create more liveable neighbourhoods be evaluated? An overview of the RESIDential Environment Project.

PubMed

Giles-Corti, Billie; Knuiman, Matthew; Pikora, Terri J; Van Neil, Kimberly; Timperio, Anna; Bull, Fiona C L; Shilton, Trevor; Bulsara, Max

2007-01-01

There is growing interest in the impact of community design on the health of residents. In 1998, the Western Australian Government began a trial of new subdivision design codes (i.e. Liveable Neighbourhoods Community Design Code) aimed at creating pedestrian-friendly neighbourhoods to increase walking, cycling and public transport use. The trial provided a unique opportunity for a natural experiment to evaluate the impact of a government planning policy on residents. Nevertheless, evaluations of this kind present a number of methodological challenges in obtaining the highest quality evidence possible. This paper describes the RESIDential Environment Project's study design and discusses how various methodological challenges were overcome.

The GAMCIT gamma ray burst detector

NASA Technical Reports Server (NTRS)

Mccall, Benjamin J.; Grunsfeld, John M.; Sobajic, Srdjan D.; Chang, Chinley Leonard; Krum, David M.; Ratner, Albert; Trittschuh, Jennifer E.

1993-01-01

The GAMCIT payload is a Get-Away-Special payload designed to search for high-energy gamma-ray bursts and any associated optical transients. This paper presents details on the design of the GAMCIT payload, in the areas of battery selection, power processing, electronics design, gamma-ray detection systems, and the optical imaging of the transients. The paper discusses the progress of the construction, testing, and specific design details of the payload. In addition, this paper discusses the unique challenges involved in bringing this payload to completion, as the project has been designed, constructed, and managed entirely by undergraduate students. Our experience will certainly be valuable to other student groups interested in taking on a challenging project such as a Get-Away-Special payload.

Alcohol Use History and Panic-Relevant Responding among Adolescents: A Test using a Voluntary Hyperventilation Challenge

PubMed Central

Blumenthal, Heidemarie; Leen-Feldner, Ellen W.; Knapp, Ashley A.; Bunaciu, Liviu; Zamboanga, Byron L.

2012-01-01

Given the onset of alcohol use, neurological sensitivity, and enhanced panic-relevant vulnerability, adolescence is a key period in which to study the documented linkage between alcohol and panic-related problems. The current study was designed to build upon and uniquely extend extant work via (1) utilization of well-established experimental psychopathology techniques, and (2) evaluation of unique associations between alcohol use and panic symptoms after controlling for theoretically-relevant behavioral, environmental, and individual difference variables (i.e., age, gender, negative affectivity, anxiety sensitivity, child and parent tobacco use, and parental panic disorder). Participants were 111 community-recruited adolescents ages 12–17 years (M = 15.76 years; n = 50 girls). Youth completed a battery of well-established questionnaires and a voluntary hyperventilation challenge, and parents present at the laboratory completed a structured clinical interview. Adolescent alcohol use was categorized as Non-Users, Experimenters, or Users. Panic symptoms were indexed via retrospective self-report and adolescents’ response to a biological challenge procedure (i.e., voluntary hyperventilation). After controlling for theoretically-relevant covariates, Users evidenced elevated panic-relevant symptoms and responding compared to Non-Users; Experimenters did not differ from Non-Users. Findings suggest alcohol use history is uniquely associated with panic symptomatology among youth, including “real-time” reactivity elicited by a laboratory challenge. While there is significant work yet to be done, these data advance extant work and lay the groundwork for the types of sophisticated designs that will be needed to answer the most pressing and complex questions regarding the link between alcohol use and panic symptoms among adolescents. PMID:22369219

Constructibility Challenges for Perimeter Control Blasting and Slope Development in Shale and Other "Weak" Rocks

NASA Astrophysics Data System (ADS)

Scarpato, D. J.

2016-02-01

Slope construction in shale can present some interesting challenges for geotechnical design engineers and contractors alike. There are challenges that can be expected and designed for; however, all too frequently, such challenges manifest themselves as "surprises" in the field. Common constructibility challenges can include drill hole deviation during drilling for controlled blasting; and, excavation slope instability arising from inconsistent perimeter control drilling. Drill hole deviation results from the cumulative effects from both drilling mechanics and rock mass conditions. Once a hole has initiated the deviation trajectory, it is difficult to rectify drill steel position. Although such challenges are not necessarily unique to shale, they are often exacerbated by weak, weathered and transversely isotropic nature of bedrock conditions. All too often, the working assumption is that shale is "soft" and easily excavatable; however, this blanket assumption can prove to be costly. This paper is intended to provide design professionals and contractors with the practical considerations needed to avoid the "surprises" associated with drill hole deviation, and minimize the potential for costly claims.

Exposing the Challenges and Coping Strategies of Field-Ecology Graduate Students

NASA Astrophysics Data System (ADS)

Leon-Beck, Mika; Dodick, Jeff

2012-11-01

In this paper, we expose the unique challenges confronting graduate field-ecology students and the coping strategies they adopt to overcome such challenges. To do so, we used a qualitative (in vivo) research method that combines interviews, observations and open questionnaires with a group of five Israeli graduate students. The two major challenges that the students faced were the uncontrolled nature of field research (or complexity), and the nature of field setting, which isolated the students from authoritative guidance. In response to these challenges, the students developed a set of research skills which were expressed in this study by a series of three (metacognitive) strategies which we designated as 'protocol-dominated', 'intermediate' or 'field-dominated'. In order to develop such research skills, our subjects rely upon declarative and procedural knowledge. In contrast to declarative knowledge, learned in coursework, procedural knowledge is learned and activated via the situated experience of implementing research in authentic field environments. We also found that fieldwork complexity imposes itself the minute the students step into the field; potentially, this can negatively impact students' motivation. However, as the students accumulate field experience and acquire the knowledge and skills needed to overcome the field's complexity, their motivation improves. Recognizing the unique learning components connected to field research will help novice students better cope with fieldwork challenges, as well as help their advisers in guiding them. This work also has implications for designing inquiry curricula in field sciences for university and high-school students.

Entry, Descent, and Landing Mission Design for the Crew Exploration Vehicle Thermal Protection System Qualification Flight Test

NASA Technical Reports Server (NTRS)

Ivanov, Mark; Strauss, William; Maddock, Robert

2007-01-01

The TORCH team was challenged to generate the lowest cost mission design solution that meets the CEV aerothermal test objectives on a sub-scale flight article. The test objectives resulted from producing representative lunar return missions and observing the aerothermal envelopes of select surface locations on the CEV. From these aerothermal envelopes, two test boxes were established: one for high shear and one for high radiation. The unique and challenging trajectory design objective for the flight test was to fly through these aerothermal boxes in shear, pressure, heat flux, and radiation while also not over testing. These test boxes, and the max aerothermal limits, became the driving requirements for defining the mission design.

Recent Experiences and Challenges of Military Physiotherapists Deployed to Afghanistan: A Qualitative Study

PubMed Central

Carpenter, Christine

2011-01-01

ABSTRACT Purpose: Military physiotherapists in the Canadian Forces meet the unique rehabilitation needs of military personnel. Recently, the physiotherapy officer role has evolved in response to the Canadian Forces' involvement in the combat theatre of operations of Afghanistan, and this has created new and unique challenges and demands. The purpose of this study was to describe the experiences and challenges of military physiotherapists deployed to Afghanistan. Methods: A qualitative research design guided by descriptive phenomenology involved recruitment of key informants and in-depth interviews as the data collection method. The interviews were transcribed verbatim and the data analyzed using a foundational thematic analysis approach. Strategies of peer review and member checking were incorporated into the study design. Results: Six military physiotherapists were interviewed. They described rewarding experiences that were stressful yet highly career-satisfying. Main challenges revolved around heavy workloads, an expanded scope of practice as sole-charge practitioners, and the consequences and criticality of their clinical decisions. Conclusions: Our findings suggest that enhanced pre-deployment training and the implementation of a stronger support network will improve the capabilities of military physiotherapists deployed to difficult theatres of operations. This type of systematic and comprehensive research is needed to assist the Canadian Forces in proactively preparing and supporting physiotherapists deployed on future missions. PMID:22942524

Adventures in Evaluation: Reviewing a CD-ROM Based Adventure Game Designed for Young People Recovering from Psychosis

ERIC Educational Resources Information Center

Shrimpton, Bradley; Hurworth, Rosalind

2005-01-01

Recently the Centre for Program Evaluation (CPE) at the University of Melbourne was approached by a mental health agency to undertake the unique and challenging task of evaluating a prototype CD-ROM based adventure game designed for young people recovering from psychosis. This unusual and inventive game, titled Pogo's Pledge, used…

Mars outpost - System and operations challenges

NASA Technical Reports Server (NTRS)

Roberts, Barney; Guerra, Lisa

1990-01-01

The paper addresses the challenges inherent in establishing an outpost on the planet Mars. For background purposes, the unique, remote Martian environment and the developmental phases of a settlement in such an environment are discussed. Challenges are identified in terms of surface systems and operations. Due to its importance to habitability, the life support system (LSS) is highlighted with various options identified. Operations for the Mars outpost, earth-based and local, are characterized by a decentralized concept. The challenge of integrating logistics analysis early in system design and operations strategy is also addressed. In order to understand and reduce the system and operations challenges, the application of terrestrial and lunar testbeds is explained.

High Gain Antenna Gimbal for the 2003-2004 Mars Exploration Rover Program

NASA Technical Reports Server (NTRS)

Sokol, Jeff; Krishnan, Satish; Ayari, Laoucet

2004-01-01

The High Gain Antenna Assemblies built for the 2003-2004 Mars Exploration Rover (MER) missions provide the primary communication link for the Rovers once they arrive on Mars. The High Gain Antenna Gimbal (HGAG) portion of the assembly is a two-axis gimbal that provides the structural support, pointing, and tracking for the High Gain Antenna (HGA). The MER mission requirements provided some unique design challenges for the HGAG. This paper describes all the major subsystems of the HGAG that were developed to meet these challenges, and the requirements that drove their design.

Human Factors in Streaming Data Analysis: Challenges and Opportunities for Information Visualization: Human Factors in Streaming Data Analysis

DOE Office of Scientific and Technical Information (OSTI.GOV)

Dasgupta, Aritra; Arendt, Dustin L.; Franklin, Lyndsey R.

Real-world systems change continuously and across domains like traffic monitoring, cyber security, etc., such changes occur within short time scales. This leads to a streaming data problem and produces unique challenges for the human in the loop, as analysts have to ingest and make sense of dynamic patterns in real time. In this paper, our goal is to study how the state-of-the-art in streaming data visualization handles these challenges and reflect on the gaps and opportunities. To this end, we have three contributions: i) problem characterization for identifying domain-specific goals and challenges for handling streaming data, ii) a survey andmore » analysis of the state-of-the-art in streaming data visualization research with a focus on the visualization design space, and iii) reflections on the perceptually motivated design challenges and potential research directions for addressing them.« less

OMV man/system simulation integration: A preliminary analysis and recommendation

NASA Technical Reports Server (NTRS)

Rogers, Jon G.

1988-01-01

The Orbital Maneuvering Vehicle (OMV) presents a series of challenges to the human operator. Some are unique to the OMV system itself, and are largely due to remote control versus control from the cockpit. Other challenges are not necessarily unique to the OMV, but are characteristic of many man-machine space flight systems. All of these challenges affect the operator's ability to perform his portion of the mission, and could lead to human error which might jeopardize the vehicle, mission, or both. It is imperative to make every effort to design the control and displays to facilitate the operator's task. The experimental program should address the perceptual, mediational, and motor dimensions of operator performance. With this in mind, a literature review with relevant design considerations was initiated, and a comprehensive outline of control/display parameters were developed. Out of this, a series of questions not answered in the literature was derived which can be converted into experimental protocols for the simulation program. A major task of the aircraft pilot as well as the OMV operator is prediction. Certain display principles have proved to enhance the pilot's ability to predict. A brief examination of some of these principles in relationship to OMV may be useful.

Australia’s Submarine Design Capabilities and Capacities: Challenges and Options for the Future Submarine

DTIC Science & Technology

2011-01-01

stealth features requiring specialised noise and vibra- tion skills and propulsion plants requiring other unique skill sets. Personnel with these...analysis Acoustic, wake , thermal, electromagnetic, and other signature analysis Combat systems and ship control Combat system integration, combat system...to-diagnose flow-induced radiated noise Own-sensor performance degradation Note: Risks can be reduced for given designs using scale models

Research Suggestions in the Design of a Global Graduate Business Program Delivered by Online Learning

ERIC Educational Resources Information Center

Puderbaugh, Amy

2015-01-01

The purpose of this paper was to examine the unique areas of concern when establishing an eLearning program in the field of global business. A survey of eLearning and a global management subject matter appears. This paper identifies potential challenges in program design and raises practical concerns for future research. [For the full proceedings,…

Design Principles for Equity and Excellence at Hispanic-Serving Institutions. PERSPECTIVAS: Issues in Higher Education Policy and Practice. Issue No. 4, Spring 2015

ERIC Educational Resources Information Center

Malcom-Piqueux, Lindsey E.; Bensimon, Estela Mara

2015-01-01

Hispanic-Serving Institutions (HSIs) shoulder unique responsibilities, including the education of post-traditional student populations, while facing distinct resource-related challenges. Any efforts to assess the performance of HSIs must be done with these facts in mind. This brief offers design principles for equity and excellence at HSIs that…

Optimizing Cognitive Rehabilitation: Effective Instructional Methods

ERIC Educational Resources Information Center

Sohlberg, McKay Moore; Turkstra, Lyn S.

2011-01-01

Rehabilitation professionals face a key challenge when working with clients with acquired cognitive impairments: how to teach new skills to individuals who have difficulty learning. Unique in its focus, this book presents evidence-based instructional methods specifically designed to help this population learn more efficiently. The expert authors…

Exploring Parental Involvement Strategies Utilized by Middle School Interdisciplinary Teams

ERIC Educational Resources Information Center

Robbins, Chris; Searby, Linda

2013-01-01

Adolescents present a unique collection of characteristics and challenges which middle school interdisciplinary teams were designed to address. This article describes a research study which explored parental involvement strategies employed by interdisciplinary teaching teams from three very different middle schools: an affluent suburban school, a…

The conundrum of harmonizing resistance surveillance systems on a global level

USDA-ARS?s Scientific Manuscript database

Surveillance systems, particularly those involving complex data over time, provide unique challenges. They are as varied in design, intent, funding and function as the countries in which they exist. The Centers for Disease Control and Prevention define surveillance as ‘the ongoing systematic colle...

Incorporating CCSDS telemetry standards and philosophy on Cassini

NASA Technical Reports Server (NTRS)

Day, John C.; Elson, Anne B.

1995-01-01

The Cassini project at the Jet Propulsion Laboratory (JPL) is implementing a spacecraft telemetry system based on the Consultative Committee for Space Data Systems (CCSDS) packet telemetry standards. Resolving the CCSDS concepts with a Ground Data System designed to handle time-division-multiplexed telemetry and also handling constraints unique to a deep-space planetary spacecraft (such as fixed downlink opportunities, small downlink rates and requirements for on-board data storage) have resulted in spacecraft and ground system design challenges. Solving these design challenges involved adapting and extending the CCSDS telemetry standards as well as changes to the spacecraft and ground system designs. The resulting spacecraft/ground system design is an example of how new ideas and philosophies can be incorporated into existing systems and design approaches without requiring significant rework. In addition, it shows that the CCSDS telemetry standards can be successfully applied to deep-space planetary spacecraft.

Structural and mechanical design challenges of space shuttle solid rocket boosters separation and recovery subsystems

NASA Technical Reports Server (NTRS)

Woodis, W. R.; Runkle, R. E.

1985-01-01

The design of the space shuttle solid rocket booster (SRB) subsystems for reuse posed some unique and challenging design considerations. The separation of the SRBs from the cluster (orbiter and external tank) at 150,000 ft when the orbiter engines are running at full thrust meant the two SRBs had to have positive separation forces pushing them away. At the same instant, the large attachments that had reacted launch loads of 7.5 million pounds thrust had to be servered. These design considerations dictated the design requirements for the pyrotechnics and separation rocket motors. The recovery and reuse of the two SRBs meant they had to be safely lowered to the ocean, remain afloat, and be owed back to shore. In general, both the pyrotechnic and recovery subsystems have met or exceeded design requirements. In twelve vehicles, there has only been one instance where the pyrotechnic system has failed to function properly.

System Definition of the James Webb Space Telescope (JWST) Integrated Science Instrument Module (ISIM)

NASA Technical Reports Server (NTRS)

Lundquist, Ray; Aymergen, Cagatay; VanCampen, Julie; Abell, James; Smith, Miles; Driggers, Phillip

2008-01-01

The Integrated Science Instrument Module (ISIM) for the James Webb Space Telescope (JWST) provides the critical functions and the environment for the four science instruments on JWST. This complex system development across many international organizations presents unique challenges and unique solutions. Here we describe how the requirement flow has been coordinated through the documentation system, how the tools and processes are used to minimize impact to the development of the affected interfaces, how the system design has matured, how the design review process operates, and how the system implementation is managed through reporting to ensure a truly world class scientific instrument compliment is created as the final product.

Concept Design of High Power Solar Electric Propulsion Vehicles for Human Exploration

NASA Technical Reports Server (NTRS)

Hoffman, David J.; Kerslake, Thomas W.; Hojnicki, Jeffrey S.; Manzella, David H.; Falck, Robert D.; Cikanek, Harry A., III; Klem, Mark D.; Free, James M.

2011-01-01

Human exploration beyond low Earth orbit will require enabling capabilities that are efficient, affordable and reliable. Solar electric propulsion (SEP) has been proposed by NASA s Human Exploration Framework Team as one option to achieve human exploration missions beyond Earth orbit because of its favorable mass efficiency compared to traditional chemical propulsion systems. This paper describes the unique challenges associated with developing a large-scale high-power (300-kWe class) SEP vehicle and design concepts that have potential to meet those challenges. An assessment of factors at the subsystem level that must be considered in developing an SEP vehicle for future exploration missions is presented. Overall concepts, design tradeoffs and pathways to achieve development readiness are discussed.

Construction of the GAMCIT gamma-ray burst detector (G-056)

NASA Technical Reports Server (NTRS)

Coward, Michael H.; Grunsfeld, John M.; Mccall, Benjamin J.; Ratner, Albert

1995-01-01

The GAMCIT (Gamma-ray Astrophysics Mission, California Institute of Technology) payload is a Get-Away-Special payload designed to search for high-energy gamma-ray bursts and any associated optical transients. This paper presents details on the development and construction of the GAMCIT payload. In addition, this paper will reflect upon the unique challenges involved in bringing the payload close to completion, as the project has been designed, constructed, and managed entirely by undergraduate members of the Caltech SEDS (Students for the Exploration and Development of Space). Our experience will definitely be valuable to other student groups interested in undertaking a challenge such as a Get-Away-Special payload.

Design Analysis of a High Temperature Radiator for the Variable Specific Impulse Magnetoplasma Rocket (VASIMR)

NASA Technical Reports Server (NTRS)

Sheth, Rubik B.; Ungar, Eugene K.; Chambliss, Joe P.; Cassady, Leonard D.

2011-01-01

The Variable Specific Impulse Magnetoplasma Rocket (VASIMR), currently under development by Ad Astra Rocket Company, is a unique propulsion system that can potentially change the way space propulsion is performed. VASIMR's efficiency, when compared to that of a conventional chemical rocket, reduce propellant needed for exploration missions by a factor of 10. Currently plans include flight tests of a 200 kW VASIMR system, titled VF-200, on the International Space Station. The VF-200 will consist of two 100 kW thruster units packaged together in one engine bus. Each thruster unit has a unique heat rejection requirement of about 27 kW over a firing time of 15 minutes. In order to control rocket core temperatures, peak operating temperatures of about 300 C are expected within the thermal control loop. Design of a high temperature radiator is a unique challenge for the vehicle design. This paper will discuss the path taken to develop a steady state and transient based radiator design. The paper will describe radiator design options for the VASIMR thermal control system for use on ISS as well as future exploration vehicles.

Student Service Members/Veterans on Campus: Challenges for Reintegration

PubMed Central

Borsari, Brian; Yurasek, Ali; Miller, Mary Beth; Murphy, James G.; McDevitt-Murphy, Meghan E.; Martens, Matthew P.; Darcy, Monica G.; Carey, Kate B.

2016-01-01

Many returning OIF/OEF/OND Veterans are seeking higher education in an effort to develop a meaningful career and financial stability. Evidence suggests that student service members/Veterans (SSM/Vs) are experiencing less academic success than other students. The purpose of this review is to identify the unique challenges of SSM/Vs and evaluate current campus efforts to facilitate their retention and academic performance. With a focus on SSM/Vs attending colleges and universities, we obtained 57 peer-reviewed and 73 grey literature records published between 2001 and 2015. The current SSM/V literature contains an abundance of grey literature, and the empirical research tends to be limited by cross-sectional design and small sample sizes. SSM/Vs encounter significant personal and environmental challenges when transitioning from the military to college campuses. A variety of services have been developed to address the needs of the SSM/V population, but the efficacy of these services remains largely unknown. In conclusion, there is a clear need to provide education to faculty, students and staff regarding the experiences of SSM/Vs. Efforts to enhance screening for, availability of, and SSM/V engagement in mental health services would also be beneficial, as would improved availability of and SSM/V access to academic support. All future programs designed to address the unique challenges of SSM/Vs in the academic environment should also be systematically implemented and evaluated. PMID:28206804

Low-Power, Chip-Scale, Carbon Dioxide Gas Sensors for Spacesuit Monitoring

NASA Technical Reports Server (NTRS)

Rani, Asha; Shi, Chen; Thomson, Brian; Debnath, Ratan; Wen, Boamei; Motayed, Abhishek; Chullen, Cinda

2018-01-01

N5 Sensors, Inc. through a Small Business Technology Transfer (STTR) contract award has been developing ultra-small, low-power carbon dioxide (CO2) gas sensors, suited for monitoring CO2 levels inside NASA spacesuits. Due to the unique environmental conditions within the spacesuits, such as high humidity, large temperature swings, and operating pressure swings, measurement of key gases relevant to astronaut's safety and health such as(CO2), is quite challenging. Conventional non-dispersive infrared absorption based CO2 sensors present challenges inside the spacesuits due to size, weight, and power constraints, along with the ability to sense CO2 in a high humidity environment. Unique chip-scale, nanoengineered chemiresistive gas-sensing architecture has been developed for this application, which can be operated in a typical space-suite environmental conditions. Unique design combining the selective adsorption properties of the nanophotocatalytic clusters of metal-oxides and metals, provides selective detection of CO2 in high relative humidity conditions. All electronic design provides a compact and low-power solution, which can be implemented for multipoint detection of CO2 inside the spacesuits. This paper will describe the sensor architecture, development of new photocatalytic material for better sensor response, and advanced structure for better sensitivity and shorter response times.

Reducing Structural Weight and Increasing Protection in Simple Structures Subjected to Blast Loads

DTIC Science & Technology

2014-08-12

centric vehicle structures that make the operation of the vehicle both comfortable and safe for the soldiers. Furthermore, a lighter weight vehicle...supporting forces. Therefore, a key design challenge is to develop lightweight occupant-centric vehicle structures that can provide high levels of...protection against explosive threats. In this paper, concepts for using materials, damping and other mechanisms to design structures with unique dynamic

DOE Office of Scientific and Technical Information (OSTI.GOV)

Bernardin, John D; Baca, Allen G

This paper presents the mechanical design, fabrication and dynamic testing of an electrostatic analyzer spacecraft instrument. The functional and environmental requirements combined with limited spacecraft accommodations, resulted in complex component geometries, unique material selections, and difficult fabrication processes. The challenging aspects of the mechanical design and several of the more difficult production processes are discussed. In addition, the successes, failures, and lessons learned from acoustic and random vibration testing of a full-scale prototype instrument are presented.

Teaching Informatics to Prelicensure, RN-to-BSN, and Graduate Level Students.

PubMed

Vottero, Beth

Teaching nursing informatics to students in associate, baccalaureate, RN-BSN, and graduate nursing programs poses challenges for curriculum design, as well as developing appropriate instruction and assessment methods. The current state of nursing informatics education provides opportunities for unique instructional design and assessment techniques. Key course content is provided with suggestions for teaching informatics that focus on leveling for prelicensure, RN-BSN, and graduate nursing programs.

Ni-Ti Alloys for Aerospace Bearing Applications

NASA Technical Reports Server (NTRS)

DellaCorte, Christopher

2017-01-01

Nickel-rich Ni-Ti alloys are emerging candidate materials for aerospace bearing applications. These alloys exhibit a unique combination of physical, chemical, and tribological properties that are highly relevant to challenging aerospace bearings and other mechanical components. Despite being made solely from metals, Ni-Ti alloys are classified as intermetallics with properties akin to both metals and ceramics. For instance, like metals, they are electrically conductive but they tend to be brittle like ceramics. When properly processed, they have high hardness, low elastic modulus and an extensive elastic deformation range that imparts extraordinarily high resilience and resistance to denting. New alloy compositions enable simpler thermal processing and machining and intensive microstructural analyses have helped elucidate the materials science mechanisms governing hardness. In this paper, the application of state-of-art in NiTi alloys for aerospace bearings and mechanical components is explored. In addition to reviewing future trends and remaining challenges, the unique approaches and methods of tailoring bearing design to accommodate NiTis unique properties is discussed.

Overview of Engineering Design and Analysis at the NASA John C. Stennis Space Center

NASA Technical Reports Server (NTRS)

Ryan, Harry; Congiardo, Jared; Junell, Justin; Kirkpatrick, Richard

2007-01-01

A wide range of rocket propulsion test work occurs at the NASA John C. Stennis Space Center (SSC) including full-scale engine test activities at test facilities A-1, A-2, B-1 and B-2 as well as combustion device research and development activities at the E-Complex (E-1, E-2, E-3 and E-4) test facilities. The propulsion test engineer at NASA SSC faces many challenges associated with designing and operating a test facility due to the extreme operating conditions (e.g., cryogenic temperatures, high pressures) of the various system components and the uniqueness of many of the components and systems. The purpose of this paper is to briefly describe the NASA SSC Engineering Science Directorate s design and analysis processes, experience, and modeling techniques that are used to design and support the operation of unique rocket propulsion test facilities.

Teaching Cultural Geography with "The Amazing Race"

ERIC Educational Resources Information Center

Smiley, Sarah L.

2017-01-01

The reality show "The Amazing Race" serves as a useful text for the cultural geography classroom. As competitors travel the world, they complete challenging tasks designed to be both educational and entertaining. Audiences see actual images from destinations around the world and learn about the unique cultures of these places. They also…

Designing Inclusive Learning for Twice Exceptional Students in Minecraft

ERIC Educational Resources Information Center

O'Sullivan, Muireann; Robb, Nigel; Howell, Stephen; Marshall, Kevin; Goodman, Lizbeth

2017-01-01

Twice exceptional learners are intellectually or creatively gifted yet also experience one or more learning difficulties. These students face a unique set of challenges in educational settings. Recommended strategies for accommodating twice exceptional learners focus on--among other things--(1) providing freedom and variety, so that students can…

Lesbian Presentations and Representations of Leadership, and the Implications for HRD

ERIC Educational Resources Information Center

Gedro, Julie

2010-01-01

Purpose: This paper seeks to identify, examine, and discuss the unique challenges for lesbians who serve in leadership positions in corporate America. Design/methodology/approach: Drawing upon a multi-disciplinary framework of management, diversity, feminist, and leadership literature, the paper critically examines the myriad of pressures exerted…

Teachers, Micro-Credentials, and the Performance Assessment Movement

ERIC Educational Resources Information Center

French, Dan; Berry, Barnett

2017-01-01

Micro-credentials, a new form of personalized professional development for teachers, offer a unique solution to the challenge of training school staff to design and implement performance assessments. In a relatively short period of time, micro-credentials have shown promise in enabling a more personalized, effective method of promoting teacher…

Share (And Not) Share Alike: Improving Virtual Team Climate and Decision Performance

ERIC Educational Resources Information Center

Cordes, Sean

2017-01-01

Virtual teams face unique communication and collaboration challenges that impact climate development and performance. First, virtual teams rely on technology mediated communication which can constrain communication. Second, team members lack skill for adapting process to the virtual setting. A collaboration process structure was designed to…

Growth Models for Students with Significant Cognitive Disabilities. Research Brief 1

ERIC Educational Resources Information Center

Farley, Dan; Saven, Jessica L.; Tindal, Gerald

2013-01-01

Alternate assessments based on alternate achievement standards (AA-AAS) are designed to measure the academic achievement of students with the most significant cognitive disabilities (SWSCDs). AA-AAS present unique measurement challenges because of the inherent need for individualization in item presentation and response, combined with expectations…

Global Imagery in Online Advertisements

ERIC Educational Resources Information Center

Hynes, Geraldine E.; Janson, Marius

2007-01-01

A well-designed online advertisement is essential for effective communication with potential customers and contributes to successful e-commerce. However, creating online sales messages that appeal to a broad range of cultures can pose unique challenges. Internet ads must offer both a globally appealing and a culture-specific message that in turn…

Solid Rocket Booster (SRB) - Evolution and Lessons Learned During the Shuttle Program

NASA Technical Reports Server (NTRS)

Kanner, Howard S.; Freeland, Donna M.; Olson, Derek T.; Wood, T. David; Vaccaro, Mark V.

2011-01-01

The Solid Rocket Booster (SRB) element integrates all the subsystems needed for ascent flight, entry, and recovery of the combined Booster and Motor system. These include the structures, avionics, thrust vector control, pyrotechnic, range safety, deceleration, thermal protection, and retrieval systems. This represents the only human-rated, recoverable and refurbishable solid rocket ever developed and flown. Challenges included subsystem integration, thermal environments and severe loads (including water impact), sometimes resulting in hardware attrition. Several of the subsystems evolved during the program through design changes. These included the thermal protection system, range safety system, parachute/recovery system, and others. Obsolescence issues occasionally required component recertification. Because the system was recovered, the SRB was ideal for data and imagery acquisition, which proved essential for understanding loads and system response. The three main parachutes that lower the SRBs to the ocean are the largest parachutes ever designed, and the SRBs are the largest structures ever to be lowered by parachutes. SRB recovery from the ocean was a unique process and represented a significant operational challenge; requiring personnel, facilities, transportation, and ground support equipment. The SRB element achieved reliability via extensive system testing and checkout, redundancy management, and a thorough postflight assessment process. Assembly and integration of the booster subsystems was a unique process and acceptance testing of reused hardware components was required for each build. Extensive testing was done to assure hardware functionality at each level of stage integration. Because the booster element is recoverable, subsystems were available for inspection and testing postflight, unique to the Shuttle launch vehicle. Problems were noted and corrective actions were implemented as needed. The postflight assessment process was quite detailed and a significant portion of flight operations. The SRBs provided fully redundant critical systems including thrust vector control, mission critical pyrotechnics, avionics, and parachute recovery system. The design intent was to lift off with full redundancy. On occasion, the redundancy management scheme was needed during flight operations. This paper describes some of the design challenges, how the design evolved with time, and key areas where hardware reusability contributed to improved system level understanding.

Space Shuttle Star Tracker Challenges

NASA Technical Reports Server (NTRS)

Herrera, Linda M.

2010-01-01

The space shuttle fleet of avionics was originally designed in the 1970's. Many of the subsystems have been upgraded and replaced, however some original hardware continues to fly. Not only fly, but has proven to be the best design available to perform its designated task. The shuttle star tracker system is currently flying as a mixture of old and new designs, each with a unique purpose to fill for the mission. Orbiter missions have tackled many varied missions in space over the years. As the orbiters began flying to the International Space Station (ISS), new challenges were discovered and overcome as new trusses and modules were added. For the star tracker subsystem, the growing ISS posed an unusual problem, bright light. With two star trackers on board, the 1970's vintage image dissector tube (IDT) star trackers track the ISS, while the new solid state design is used for dim star tracking. This presentation focuses on the challenges and solutions used to ensure star trackers can complete the shuttle missions successfully. Topics include KSC team and industry partner methods used to correct pressurized case failures and track system performance.

Miniature objective lens for array digital pathology: design improvement based on clinical evaluation

NASA Astrophysics Data System (ADS)

McCall, Brian; Pierce, Mark; Graviss, Edward A.; Richards-Kortum, Rebecca R.; Tkaczyk, Tomasz S.

2016-03-01

A miniature objective designed for digital detection of Mycobacterium tuberculosis (MTB) was evaluated for diagnostic accuracy. The objective was designed for array microscopy, but fabricated and evaluated at this stage of development as a single objective. The counts and diagnoses of patient samples were directly compared for digital detection and standard microscopy. The results were found to be correlated and highly concordant. The evaluation of this lens by direct comparison to standard fluorescence sputum smear microscopy presented unique challenges and led to some new insights in the role played by the system parameters of the microscope. The design parameters and how they were developed are reviewed in light of these results. New system parameters are proposed with the goal of easing the challenges of evaluating the miniature objective and maintaining the optical performance that produced the agreeable results presented without over-optimizing. A new design is presented that meets and exceeds these criteria.

Conducting transcultural research: critical thinking in Thailand.

PubMed

Jenkins, Sheryl D

2011-01-01

Little has been written to help researchers prepare for the unique challenges of conducting transcultural research. The purpose of this article is to discuss issues that arose during the planning and execution of a transcultural study designed to compare critical thinking in Thailand and the United States. The challenges of identifying a research site, selecting participants, incorporating Thai research into the literature review, traveling and living in a foreign culture, overcoming cultural barriers to research, and strengthening internal validity and reliability are addressed.

Transgender populations and HIV: unique risks, challenges and opportunities.

PubMed

Wansom, Tanyaporn; Guadamuz, Thomas E; Vasan, Sandhya

2016-04-01

Due to unique social, behavioural, structural and biological issues, transgender (TG) populations, especially TG women, are at high risk for HIV acquisition. This increased risk is multifactorial, due to differing psychosocial risk factors, poorer access to TG-specific healthcare, a higher likelihood of using exogenous hormones or fillers without direct medical supervision, interactions between hormonal therapy and antiretroviral therapy, and direct effects of hormonal therapy on HIV acquisition and immune control. Further research is needed to elucidate these mechanisms of risk and to help design interventions to reduce HIV risk among transgender populations.

V&V of Fault Management: Challenges and Successes

NASA Technical Reports Server (NTRS)

Fesq, Lorraine M.; Costello, Ken; Ohi, Don; Lu, Tiffany; Newhouse, Marilyn

2013-01-01

This paper describes the results of a special breakout session of the NASA Independent Verification and Validation (IV&V) Workshop held in the fall of 2012 entitled "V&V of Fault Management: Challenges and Successes." The NASA IV&V Program is in a unique position to interact with projects across all of the NASA development domains. Using this unique opportunity, the IV&V program convened a breakout session to enable IV&V teams to share their challenges and successes with respect to the V&V of Fault Management (FM) architectures and software. The presentations and discussions provided practical examples of pitfalls encountered while performing V&V of FM including the lack of consistent designs for implementing faults monitors and the fact that FM information is not centralized but scattered among many diverse project artifacts. The discussions also solidified the need for an early commitment to developing FM in parallel with the spacecraft systems as well as clearly defining FM terminology within a project.

The pressing energy innovation challenge of the US National Laboratories

NASA Astrophysics Data System (ADS)

Anadon, Laura Diaz; Chan, Gabriel; Bin-Nun, Amitai Y.; Narayanamurti, Venkatesh

2016-10-01

Accelerating the development and deployment of energy technologies is a pressing challenge. Doing so will require policy reform that improves the efficacy of public research organizations and strengthens the links between public and private innovators. With their US$14 billion annual budget and unique mandates, the US National Laboratories have the potential to critically advance energy innovation, yet reviews of their performance find several areas of weak organizational design. Here, we discuss the challenges the National Laboratories face in engaging the private sector, increasing their contributions to transformative research, and developing culture and management practices to better support innovation. We also offer recommendations for how policymakers can address these challenges.

Exploring Perspectives and Identifying Potential Challenges Encountered with Crime Scene Investigations When Developing Chemistry Curricula

ERIC Educational Resources Information Center

Kanu, A. Bakarr; Pajski, Megan; Hartman, Machelle; Kimaru, Irene; Marine, Susan

2015-01-01

In today's complex world, there is a continued demand for recently graduated forensic chemists (criminalists) who have some background in forensic experimental techniques. This article describes modern forensic experimental approaches designed and implemented from a unique instructional perspective to present certain facets of crime scene…

Challenges and opportunities for growing blackberries in areas with adverse environmental conditions

USDA-ARS?s Scientific Manuscript database

The rotating cross-arm (RCA) technology (Fig. 1) combines a unique trellis design and cane training protocol. Developed over the last two decades, this technology is beginning to have an impact on the blackberry (Genus Rubus, subgenus Rubus) industry in the United States of America (USA). It has b...

Effects of a Peer-Mediated Intervention on Social Interactions of Students with Low-Functioning Autism and Perceptions of Typical Peers

ERIC Educational Resources Information Center

Simpson, Lisa A.; Bui, Yvonne

2016-01-01

Students with autism display challenges acquiring friendships and participating in relationships with typical peers. Social interaction is further impacted in students with low-functioning autism, necessitating consideration of their unique characteristics when designing and implementing interventions. This single-subject study examined the…

Leave the Running Shoes at Home: Addressing Elopement in the Classroom

ERIC Educational Resources Information Center

Pennington, Robert; Strange, Connie; Stenhoff, Don; Delano, Monica; Ferguson, Laura

2012-01-01

Students' leaving a designated area without permission or supervision is referred to as "elopement," and such behavior clearly presents a unique set of challenges for educational professionals. Elopement is seen in children and youth with a variety of developmental disabilities, including those with intellectual disabilities or autism, as well as…

Managing Water Quality in Wetlands with Foresty BMP's

Treesearch

Bob Rummer

2004-01-01

Forested wetlands are uniquely critical areas in forest operations that present special challenges to protect water quality. These locations are a direct interface between the impacts of forest operations and water. BMP's are designed to minimize nonpoint source pollution, but much of the science behind current guidelines is based on an understanding of erosion...

Playful Invention and Exploration. Final Evaluation Report: Executive Summary

ERIC Educational Resources Information Center

St. John; Mark; Carroll, Becky; Helms, Jen; Smith, Anita

2008-01-01

PIE (Playful Invention and Exploration) is a unique approach to learning that centers on the use of technology and design challenges to create powerful learning experiences in informal education settings. The Playful Invention and Exploration (PIE) Institute project was funded in 2005 by the National Science Foundation (NSF). Overall, 150…

Learning Instructor Intervention from MOOC Forums: Early Results and Issues

ERIC Educational Resources Information Center

Kumar, Muthu; Kan, Min-Yen; Tan, Bernard C. Y.; Ragupathi, Kiruthika

2015-01-01

With large student enrollment, MOOC instructors face the unique challenge in deciding when to intervene in forum discussions with their limited bandwidth. We study this problem of "instructor intervention." Using a large sample of forum data culled from 61 courses, we design a binary classifier to predict whether an instructor should…

Universal Design: Supporting Students with Color Vision Deficiency (CVD) in Medical Education

ERIC Educational Resources Information Center

Meeks, Lisa M.; Jain, Neera R.; Herzer, Kurt R.

2016-01-01

Color Vision Deficiency (CVD) is a commonly occurring condition in the general population. For medical students, it has the potential to create unique challenges in the classroom and clinical environments. Few studies have provided medical educators with comprehensive recommendations to assist students with CVD. This article presents a focused…

More than a Game: Learning about Climate Change through Role-Play

ERIC Educational Resources Information Center

Paschall, Melissa; Wustenhagen, Rolf

2012-01-01

Educating management students on the connections between business and climate change is essential both to their careers and to society's ability to solve the climate challenge. To impart deep and lasting learning on this topic, the authors developed a multischool negotiation simulation that is unique in its intensiveness, cross-sector design, and…

A Field Observation on the Philosophy of Teaching Islamic and Arabic Studies

ERIC Educational Resources Information Center

Yaakub, Muhamadul Bakir Hj.

2009-01-01

Implementation of educational policy in designing curriculum details stands as a basis of conceptual educational practice. It is for sure involved time and space factors to become comprehensive and constructive, especially for teaching Islamic and Arabic studies within modern educational challenges where its uniqueness values in nature should be…

The Mars Millennium Project.

ERIC Educational Resources Information Center

National Aeronautics and Space Administration, Washington, DC.

The countdown to a new century provides a unique opportunity to engage America's youth in charting a course for the future. The Mars Millennium Project challenges students across the nation to design a community yet to be imagined for the planet Mars. This interdisciplinary learning project aims to encourage K-12 students in classrooms and youth…

LSST camera grid structure made out of ceramic composite material, HB-Cesic

NASA Astrophysics Data System (ADS)

Kroedel, Matthias R.; Langton, J. Bryan

2016-08-01

In this paper we are presenting the ceramic design and the fabrication of the camera structure which is using the unique manufacturing features of the HB-Cesic technology and associated with a dedicated metrology device in order to ensure the challenging flatness requirement of 4 micron over the full array.

Adventures in Peacemaking: A Conflict Resolution Activity Guide for School-Age Programs.

ERIC Educational Resources Information Center

Kreidler, William J.; Furlong, Lisa

This guide includes hundreds of hands-on, engaging activities designed to meet the unique needs of after-school programs, camps, and recreation centers. The activities teach the skills of creative conflict resolution to school-age children through games, cooperative team challenges, drama, crafts, music, and cooking. It includes easy-to-implement…

Comprehensive Soldier Fitness: Building Resilience in a Challenging Institutional Context

ERIC Educational Resources Information Center

Cornum, Rhonda; Matthews, Michael D.; Seligman, Martin E. P.

2011-01-01

The Comprehensive Soldier Fitness (CSF) program is designed to increase psychological strength and positive performance and to reduce the incidence of maladaptive responses of the entire U.S. Army. Based on the principles of positive psychology, CSF is a historically unique approach to behavioral health in a large (1.1 million members)…

Student service members/veterans on campus: Challenges for reintegration.

PubMed

Borsari, Brian; Yurasek, Ali; Miller, Mary Beth; Murphy, James G; McDevitt-Murphy, Meghan E; Martens, Matthew P; Darcy, Monica G; Carey, Kate B

2017-01-01

Many returning OIF/OEF/OND Veterans are seeking higher education in an effort to develop a meaningful career and financial stability. Evidence suggests that student service members/veterans (SSM/Vs) are experiencing less academic success than other students. The purpose of this review is to identify the unique challenges of SSM/Vs and evaluate current campus efforts to facilitate their retention and academic performance. With a focus on SSM/Vs attending colleges and universities, we obtained 57 peer-reviewed and 73 gray literature records published between 2001 and 2015. The current SSM/V literature contains an abundance of gray literature, and the empirical research tends to be limited by cross-sectional design and small sample sizes. SSM/Vs encounter significant personal and environmental challenges when transitioning from the military to college campuses. A variety of services have been developed to address the needs of the SSM/V population, but the efficacy of these services remains largely unknown. In conclusion, there is a clear need to provide education to faculty, students, and staff regarding the experiences of SSM/Vs. Efforts to enhance screening for, availability of, and SSM/V engagement in mental health services would also be beneficial, as would improved availability of and SSM/V access to academic support. All future programs designed to address the unique challenges of SSM/Vs in the academic environment should also be systematically implemented and evaluated. (PsycINFO Database Record (c) 2017 APA, all rights reserved).

Overcoming the Challenges of Implementing a Multi-Mission Distributed Workflow System

NASA Technical Reports Server (NTRS)

Sayfi, Elias; Cheng, Cecilia; Lee, Hyun; Patel, Rajesh; Takagi, Atsuya; Yu, Dan

2009-01-01

A multi-mission approach to solving the same problems for various projects is enticing. However, the multi-mission approach leads to the need to develop a configurable, adaptable and distributed system to meet unique project requirements. That, in turn, leads to a set of challenges varying from handling synchronization issues to coming up with a smart design that allows the "unknowns" to be decided later. This paper discusses the challenges that the Multi-mission Automated Task Invocation Subsystem (MATIS) team has come up against while designing the distributed workflow system, as well as elaborates on the solutions that were implemented. The first is to design an easily adaptable system that requires no code changes as a result of configuration changes. The number of formal deliveries is often limited because each delivery costs time and money. Changes such as the sequence of programs being called, a change of a parameter value in the program that is being automated should not result in code changes or redelivery.

Adaptive wing structures

NASA Astrophysics Data System (ADS)

Reed, John L., Jr.; Hemmelgarn, Christopher D.; Pelley, Bryan M.; Havens, Ernie

2005-05-01

Cornerstone Research Group, Inc. (CRG) is developing a unique adaptive wing structure intended to enhance the capability of loitering Unmanned Air Vehicles (UAVs). In order to tailor the wing design to a specific application, CRG has developed a wing structure capable of morphing in chord and increasing planform area by 80 percent. With these features, aircraft will be capable of optimizing their flight efficiency throughout the entire mission profile. The key benefit from this morphing design is increased maneuverability, resulting in improved effectiveness over the current design. During the development process CRG has overcome several challenges in the design of such a structure while incorporating advanced materials capable of maintaining aerodynamic shape and transferring aerodynamic loads while enabling crucial changes in planform shape. To overcome some of these challenges, CRG is working on integration of their shape memory polymer materials into the wing skin to enable seamless morphing. This paper will address the challenges associated with the development of a morphing aerospace structure capable of such large shape change, the materials necessary for enabling morphing capabilities, and the current status of the morphing program within CRG.

Present capabilities and future requirements for computer-aided geometric modeling in the design and manufacture of gas turbine

NASA Technical Reports Server (NTRS)

Caille, E.; Propen, M.; Hoffman, A.

1984-01-01

Gas turbine engine design requires the ability to rapidly develop complex structures which are subject to severe thermal and mechanical operating loads. As in all facets of the aerospace industry, engine designs are constantly driving towards increased performance, higher temperatures, higher speeds, and lower weight. The ability to address such requirements in a relatively short time frame has resulted in a major thrust towards integrated design/analysis/manufacturing systems. These computer driven graphics systems represent a unique challenge, with major payback opportunities if properly conceived, implemented, and applied.

Design of a large dual polarized Ku band reflectarray for space borne radar altimeter

NASA Technical Reports Server (NTRS)

Hodges, Richard E.; Zawadzki, Mark

2004-01-01

We describe the design of a large dual-beam, dual polarized reflectarray designed for a space-based radar altimeter. This application requires a 2.16 X 0.35 m aperture that can be folded for launch stowage. Low mass and >50% efficiency are also required. A reflectarray antenna offers the best approach but also presents unique technical challenges since a reflectarry has never been used in a space based radar application. In what follows, we describe the design, analysis and measurements of a breadboard test array built to demonstrate the reflectarray concept.

The challenge of logistics facilities development

NASA Technical Reports Server (NTRS)

Davis, James R.

1987-01-01

The paper discusses the experiences of a group of engineers and logisticians at John F. Kennedy Space center in the design, construction and activation of a consolidated logistics facility for support of Space Transportation System ground operations and maintenance. The planning, methodology and processes are covered, with emphasis placed on unique aspects and lessons learned. The project utilized a progressive design, baseline and build concept for each phase of construction, with the Government exercising funding and configuration oversight.

Laser beam distribution system for the HiLASE Center

NASA Astrophysics Data System (ADS)

Macúchová, Karolina; Heřmánek, Jan; Kaufman, Jan; Muresan, Mihai-George; Růžička, Jan; Řeháková, Martina; Divoký, Martin; Švandrlík, Luděk.; Mocek, Tomáś

2017-12-01

We report recent progress in design and testing of a distribution system for high-power laser beam delivery developed within the HiLASE project of the IOP in the Czech Republic. Laser beam distribution system is a technical system allowing safe and precise distribution of different laser beams from laboratories to several experimental stations. The unique nature of HiLASE lasers requires new approach, which makes design of the distribution system a state-of-the-art challenge.

Experimental verification of Space Platform battery discharger design optimization

NASA Astrophysics Data System (ADS)

Sable, Dan M.; Deuty, Scott; Lee, Fred C.; Cho, Bo H.

The detailed design of two candidate topologies for the Space Platform battery discharger, a four module boost converter (FMBC) and a voltage-fed push-pull autotransformer (VFPPAT), is presented. Each has unique problems. The FMBC requires careful design and analysis in order to obtain good dynamic performance. This is due to the presence of a right-half-plane (RHP) zero in the control-to-output transfer function. The VFPPAT presents a challenging power stage design in order to yield high efficiency and light component weight. The authors describe the design of each of these converters and compare their efficiency, weight, and dynamic characteristics.

Invited review article: high-speed flexure-guided nanopositioning: mechanical design and control issues.

PubMed

Yong, Y K; Moheimani, S O R; Kenton, B J; Leang, K K

2012-12-01

Recent interest in high-speed scanning probe microscopy for high-throughput applications including video-rate atomic force microscopy and probe-based nanofabrication has sparked attention on the development of high-bandwidth flexure-guided nanopositioning systems (nanopositioners). Such nanopositioners are designed to move samples with sub-nanometer resolution with positioning bandwidth in the kilohertz range. State-of-the-art designs incorporate uniquely designed flexure mechanisms driven by compact and stiff piezoelectric actuators. This paper surveys key advances in mechanical design and control of dynamic effects and nonlinearities, in the context of high-speed nanopositioning. Future challenges and research topics are also discussed.

Experimental verification of Space Platform battery discharger design optimization

NASA Technical Reports Server (NTRS)

Sable, Dan M.; Deuty, Scott; Lee, Fred C.; Cho, Bo H.

1991-01-01

The detailed design of two candidate topologies for the Space Platform battery discharger, a four module boost converter (FMBC) and a voltage-fed push-pull autotransformer (VFPPAT), is presented. Each has unique problems. The FMBC requires careful design and analysis in order to obtain good dynamic performance. This is due to the presence of a right-half-plane (RHP) zero in the control-to-output transfer function. The VFPPAT presents a challenging power stage design in order to yield high efficiency and light component weight. The authors describe the design of each of these converters and compare their efficiency, weight, and dynamic characteristics.

Infant Reminders Alter Sympathetic Reactivity and Reduce Couple Hostility at the Transition to Parenthood

ERIC Educational Resources Information Center

Mosek-Eilon, Vered; Hirschberger, Gilad; Kanat-Maymon, Yaniv; Feldman, Ruth

2013-01-01

The transition to parenthood marks an important developmental stage in adult life, associated with unique challenges to the partners' conflict dialogue in the formation of the family unit. Utilizing a biobehavioral experimental design, we examined the potential positive effects of the infant on the couple's conflict discussion. One…

African American Female Faculty in Predominantly White Graduate Schools of Social Work

ERIC Educational Resources Information Center

Edwards, Janice Berry; Clark, Trenette T.; Bryant, Shirley

2012-01-01

This study of African American female faculty in predominantly White schools of social work was designed to examine the unique experience of these faculties. The examination also aimed to develop a better understanding of the challenges and the experiences of these faculty members. This exploratory study sampled African American female social work…

Scaffolded Semi-Flipped General Chemistry Designed to Support Rural Students' Learning

ERIC Educational Resources Information Center

Lenczewski, Mary S.

2016-01-01

Students who lack academic maturity can sometimes feel overwhelmed in a fully flipped classroom. Here an alternative, the Semi-Flipped method, is discussed. Rural students, who face unique challenges in transitioning from high school learning to college-level learning, can particularly profit from the use of the Semi-Flipped method in the General…

Orchestrating Productive Mathematical Discussions: Five Practices for Helping Teachers Move beyond Show and Tell

ERIC Educational Resources Information Center

Stein, Mary Kay; Engle, Randi A.; Smith, Margaret S.; Hughes, Elizabeth K.

2008-01-01

Teachers who attempt to use inquiry-based, student-centered instructional tasks face challenges that go beyond identifying well-designed tasks and setting them up appropriately in the classroom. Because solution paths are usually not specified for these kinds of tasks, students tend to approach them in unique and sometimes unanticipated ways.…

Power Distance and Group Dynamics of an International Project Team: A Case Study

ERIC Educational Resources Information Center

Paulus, Trena M.; Bichelmeyer, Barbara; Malopinsky, Larissa; Pereira, Maura; Rastogi, Polly

2005-01-01

Project-based team activities are commonly used in higher education. Teams comprised of members from different national cultures can be faced with unique challenges during the creative process. Hofstede's (1991) cultural dimension of power distance was used to examine one such design team's intra- and inter-group interactions in a graduate-level…

Applying Research in Reading Comprehension to Social Studies Instruction for Middle and High School Students

ERIC Educational Resources Information Center

Swanson, Elizabeth; Wanzek, Jeanne

2014-01-01

Secondary-level content area teachers face unique challenges in helping their students successfully read, understand, and learn content from complex texts in their discipline. In this article, a set of research-based practices designed to provide effective and feasible instruction to improve students' reading and comprehension of text and content…

Embedded Library Services: From Cooperation to Collaboration to Enhance Student Learning in Asynchronous Online Course

ERIC Educational Resources Information Center

Olesova, Larisa A.; Melville, Anne Driscoll

2017-01-01

The online environment presents a unique challenge to higher education. Shifting from the face-to-face format to online not only involves rethinking course design, but requires careful consideration of when and how to teach students, how to find and evaluate information needed to successfully complete coursework. One solution is faculty teaming…

Recognising and Developing Urban Teachers: Chartered London Teacher Status

ERIC Educational Resources Information Center

Bubb, Sara; Porritt, Vivienne

2008-01-01

Chartered London Teacher (CLT) status is a unique scheme designed by London Challenge to recognise and reward teachers' achievements and provide a framework for professional development. As well as having the prestige of being a Chartered London Teacher for life, educators receive a one-time payment of 1,000 British pounds from the school budget…

Test Results from a High Power Linear Alternator Test Rig

NASA Technical Reports Server (NTRS)

Birchenough, Arthur G.; Hervol, David S.; Gardner, Brent G.

2010-01-01

Stirling cycle power conversion is an enabling technology that provides high thermodynamic efficiency but also presents unique challenges with regard to electrical power generation, management, and distribution. The High Power Linear Alternator Test Rig (HPLATR) located at the NASA Glenn Research Center (GRC) in Cleveland, OH is a demonstration test bed that simulates electrical power generation from a Stirling engine driven alternator. It implements the high power electronics necessary to provide a well regulated DC user load bus. These power electronics use a novel design solution that includes active rectification and power factor control, active ripple suppression, along with a unique building block approach that permits the use of high voltage or high current alternator designs. This presentation describes the HPLATR, the test program, and the operational results.

Test Results From a High Power Linear Alternator Test Rig

NASA Technical Reports Server (NTRS)

Birchenough, Arthur G.; Hervol, David S.; Gardner, Brent G.

2010-01-01

Stirling cycle power conversion is an enabling technology that provides high thermodynamic efficiency but also presents unique challenges with regard to electrical power generation, management, and distribution. The High Power Linear Alternator Test Rig (HPLATR) located at the NASA Glenn Research Center (GRC) in Cleveland, Ohio is a demonstration test bed that simulates electrical power generation from a Stirling engine driven alternator. It implements the high power electronics necessary to provide a well regulated DC user load bus. These power electronics use a novel design solution that includes active rectification and power factor control, active ripple suppression, along with a unique building block approach that permits the use of high voltage or high current alternator designs. This report describes the HPLATR, the test program, and the operational results.

Hydrogel scaffolds for tissue engineering: Progress and challenges

PubMed Central

El-Sherbiny, Ibrahim M.; Yacoub, Magdi H.

2013-01-01

Designing of biologically active scaffolds with optimal characteristics is one of the key factors for successful tissue engineering. Recently, hydrogels have received a considerable interest as leading candidates for engineered tissue scaffolds due to their unique compositional and structural similarities to the natural extracellular matrix, in addition to their desirable framework for cellular proliferation and survival. More recently, the ability to control the shape, porosity, surface morphology, and size of hydrogel scaffolds has created new opportunities to overcome various challenges in tissue engineering such as vascularization, tissue architecture and simultaneous seeding of multiple cells. This review provides an overview of the different types of hydrogels, the approaches that can be used to fabricate hydrogel matrices with specific features and the recent applications of hydrogels in tissue engineering. Special attention was given to the various design considerations for an efficient hydrogel scaffold in tissue engineering. Also, the challenges associated with the use of hydrogel scaffolds were described. PMID:24689032

Engineering of the LISA Pathfinder mission—making the experiment a practical reality

NASA Astrophysics Data System (ADS)

Warren, Carl; Dunbar, Neil; Backler, Mike

2009-05-01

LISA Pathfinder represents a unique challenge in the development of scientific spacecraft—not only is the LISA Test Package (LTP) payload a complex integrated development, placing stringent requirements on its developers and the spacecraft, but the payload also acts as the core sensor and actuator for the spacecraft, making the tasks of control design, software development and system verification unusually difficult. The micro-propulsion system which provides the remaining actuation also presents substantial development and verification challenges. As the mission approaches the system critical design review, flight hardware is completing verification and the process of verification using software and hardware simulators and test benches is underway. Preparation for operations has started, but critical milestones for LTP and field effect electric propulsion (FEEP) lie ahead. This paper summarizes the status of the present development and outlines the key challenges that must be overcome on the way to launch.

SFR test fixture for hemispherical and hyperhemispherical camera systems

NASA Astrophysics Data System (ADS)

Tamkin, John M.

2017-08-01

Optical testing of camera systems in volume production environments can often require expensive tooling and test fixturing. Wide field (fish-eye, hemispheric and hyperhemispheric) optical systems create unique challenges because of the inherent distortion, and difficulty in controlling reflections from front-lit high resolution test targets over the hemisphere. We present a unique design for a test fixture that uses low-cost manufacturing methods and equipment such as 3D printing and an Arduino processor to control back-lit multi-color (VIS/NIR) targets and sources. Special care with LED drive electronics is required to accommodate both global and rolling shutter sensors.

Systems engineering for very large systems

NASA Technical Reports Server (NTRS)

Lewkowicz, Paul E.

1993-01-01

Very large integrated systems have always posed special problems for engineers. Whether they are power generation systems, computer networks or space vehicles, whenever there are multiple interfaces, complex technologies or just demanding customers, the challenges are unique. 'Systems engineering' has evolved as a discipline in order to meet these challenges by providing a structured, top-down design and development methodology for the engineer. This paper attempts to define the general class of problems requiring the complete systems engineering treatment and to show how systems engineering can be utilized to improve customer satisfaction and profit ability. Specifically, this work will focus on a design methodology for the largest of systems, not necessarily in terms of physical size, but in terms of complexity and interconnectivity.

Systems engineering for very large systems

NASA Astrophysics Data System (ADS)

Lewkowicz, Paul E.

Very large integrated systems have always posed special problems for engineers. Whether they are power generation systems, computer networks or space vehicles, whenever there are multiple interfaces, complex technologies or just demanding customers, the challenges are unique. 'Systems engineering' has evolved as a discipline in order to meet these challenges by providing a structured, top-down design and development methodology for the engineer. This paper attempts to define the general class of problems requiring the complete systems engineering treatment and to show how systems engineering can be utilized to improve customer satisfaction and profit ability. Specifically, this work will focus on a design methodology for the largest of systems, not necessarily in terms of physical size, but in terms of complexity and interconnectivity.

The future of HIV prevention: prospects for an effective anti-HIV microbicide.

PubMed

Nuttall, Jeremy; Romano, Joseph; Douville, Karen; Galbreath, Caroline; Nel, Annaléne; Heyward, William; Mitchnick, Mark; Walker, Saul; Rosenberg, Zeda

2007-03-01

Topical microbicides are self-administered products for prevention of HIV transmission, and they present one of the most promising strategies for combating the HIV-AIDS epidemic. The development of microbicides is a long and complicated process, with many hurdles that are unique to this class of product, including challenges in product design, in the conduct and design of clinical trials, and in obtaining licensure of a new class of products intended for use almost exclusively in developing countries. Once they have been registered, there are additional challenges to the marketing and distribution of microbicides. An overview of the types of microbicide currently in development, and a summary of the issues and the approaches being taken to address them, are provided.

Generating a Reduced Gravity Environment on Earth

NASA Technical Reports Server (NTRS)

Dungan, Larry K.; Cunningham, Tom; Poncia, Dina

2010-01-01

Since the 1950s several reduced gravity simulators have been designed and utilized in preparing humans for spaceflight and in reduced gravity system development. The Active Response Gravity Offload System (ARGOS) is the newest and most realistic gravity offload simulator. ARGOS provides three degrees of motion within the test area and is scalable for full building deployment. The inertia of the overhead system is eliminated by an active motor and control system. This presentation will discuss what ARGOS is, how it functions, and the unique challenges of interfacing to the human. Test data and video for human and robotic systems will be presented. A major variable in the human machine interaction is the interface of ARGOS to the human. These challenges along with design solutions will be discussed.

Orion Entry, Descent, and Landing Performance and Mission Design

NASA Technical Reports Server (NTRS)

Broome, Joel M.; Johnson, Wyatt

2007-01-01

The Orion Vehicle is the next spacecraft to take humans into space and will include missions to ISS as well as missions to the Moon. As part of that challenge, the vehicle will have to accommodate multiple mission design concepts, since return from Low Earth Orbit and return from the Moon can be quite different. Commonality between the different missions as it relates to vehicle systems, guidance capability, and operations concepts is the goal. Several unique mission design concepts include the specification of multiple land-based landing sites for a vehicle with closed-loop direct and skip entry guidance, followed by a parachute descent and landing attenuation system. This includes the ability of the vehicle to accurately target and land at a designated landing site, including site location aspects, landing site size, and landing opportunities assessments. Analyses associated with these mission design and flight performance challenges and constraints will be discussed as well as potential operational concepts to provide feasibility and/or mission commonality.

Ares-I-X Stability and Control Flight Test: Analysis and Plans

NASA Technical Reports Server (NTRS)

Brandon, Jay M.; Derry, Stephen D.; Heim, Eugene H.; Hueschen, Richard M.; Bacon, Barton J.

2008-01-01

The flight test of the Ares I-X vehicle provides a unique opportunity to reduce risk of the design of the Ares I vehicle and test out design, math modeling, and analysis methods. One of the key features of the Ares I design is the significant static aerodynamic instability coupled with the relatively flexible vehicle - potentially resulting in a challenging controls problem to provide adequate flight path performance while also providing adequate structural mode damping and preventing adverse control coupling to the flexible structural modes. Another challenge is to obtain enough data from the single flight to be able to conduct analysis showing the effectiveness of the controls solutions and have data to inform design decisions for Ares I. This paper will outline the modeling approaches and control system design to conduct this flight test, and also the system identification techniques developed to extract key information such as control system performance (gain/phase margins, for example), structural dynamics responses, and aerodynamic model estimations.

Enterprise-wide implementation of digital radiography in oral and maxillofacial imaging: the University of Florida Dentistry System.

PubMed

Nair, Madhu K; Pettigrew, James C; Loomis, Jeffrey S; Bates, Robert E; Kostewicz, Stephen; Robinson, Boyd; Sweitzer, Jean; Dolan, Teresa A

2009-06-01

The implementation of digital radiography in dentistry in a large healthcare enterprise setting is discussed. A distinct need for a dedicated dental picture archiving and communication systems (PACS) exists for seamless integration of different vendor products across the system. Complex issues are contended with as each clinical department migrated to a digital environment with unique needs and workflow patterns. The University of Florida has had a dental PACS installed over 2 years ago. This paper describes the process of conversion from film-based imaging from the planning stages through clinical implementation. Dentistry poses many unique challenges as it strives to achieve better integration with systems primarily designed for imaging; however, the technical requirements for high-resolution image capture in dentistry far exceed those in medicine, as most routine dental diagnostic tasks are challenging. The significance of specification, evaluation, vendor selection, installation, trial runs, training, and phased clinical implementation is emphasized.

Hidden in plain sight: a crowdsourced public art contest to make automated external defibrillators more visible.

PubMed

Merchant, Raina M; Griffis, Heather M; Ha, Yoonhee P; Kilaru, Austin S; Sellers, Allison M; Hershey, John C; Hill, Shawndra S; Kramer-Golinkoff, Emily; Nadkarni, Lindsay; Debski, Margaret M; Padrez, Kevin A; Becker, Lance B; Asch, David A

2014-12-01

We sought to explore the feasibility of using a crowdsourcing study to promote awareness about automated external defibrillators (AEDs) and their locations. The Defibrillator Design Challenge was an online initiative that asked the public to create educational designs that would enhance AED visibility, which took place over 8 weeks, from February 6, 2014, to April 6, 2014. Participants were encouraged to vote for AED designs and share designs on social media for points. Using a mixed-methods study design, we measured participant demographics and motivations, design characteristics, dissemination, and Web site engagement. Over 8 weeks, there were 13 992 unique Web site visitors; 119 submitted designs and 2140 voted. The designs were shared 48 254 times on Facebook and Twitter. Most designers-voters reported that they participated to contribute to an important cause (44%) rather than to win money (0.8%). Design themes included: empowerment, location awareness, objects (e.g., wings, lightning, batteries, lifebuoys), and others. The Defibrillator Design Challenge engaged a broad audience to generate AED designs and foster awareness. This project provides a framework for using design and contest architecture to promote health messages.

Overview of NASA's Thermal Control System Development for Exploration Project

NASA Technical Reports Server (NTRS)

Stephan, Ryan A.

2010-01-01

NASA's Constellation Program includes the Orion, Altair, and Lunar Surface Systems project offices. The first two elements, Orion and Altair, are manned space vehicles while the third element is broader and includes several sub-elements including Rovers and a Lunar Habitat. The upcoming planned missions involving these systems and vehicles include several risks and design challenges. Due to the unique thermal environment, many of these risks and challenges are associated with the vehicles' thermal control system. NASA's Exploration Systems Mission Directorate (ESMD) includes the Exploration Technology Development Program (ETDP). ETDP consists of several technology development projects. The project chartered with mitigating the aforementioned risks and design challenges is the Thermal Control System Development for Exploration Project. The risks and design challenges are addressed through a rigorous technology development process that culminates with an integrated thermal control system test. The resulting hardware typically has a Technology Readiness Level (TRL) of six. This paper summarizes the development efforts being performed by the technology development project. The development efforts involve heat acquisition and heat rejection hardware including radiators, heat exchangers, and evaporators. The project has also been developing advanced phase change material heat sinks and performing assessments for thermal control system fluids.

Hidden in Plain Sight: A Crowdsourced Public Art Contest to Make Automated External Defibrillators More Visible

PubMed Central

Griffis, Heather M.; Kilaru, Austin S.; Sellers, Allison M.; Hershey, John C.; Hill, Shawndra S.; Kramer-Golinkoff, Emily; Nadkarni, Lindsay; Debski, Margaret M.; Padrez, Kevin A.; Becker, Lance B.; Asch, David A.

2014-01-01

Objectives. We sought to explore the feasibility of using a crowdsourcing study to promote awareness about automated external defibrillators (AEDs) and their locations. Methods. The Defibrillator Design Challenge was an online initiative that asked the public to create educational designs that would enhance AED visibility, which took place over 8 weeks, from February 6, 2014, to April 6, 2014. Participants were encouraged to vote for AED designs and share designs on social media for points. Using a mixed-methods study design, we measured participant demographics and motivations, design characteristics, dissemination, and Web site engagement. Results. Over 8 weeks, there were 13 992 unique Web site visitors; 119 submitted designs and 2140 voted. The designs were shared 48 254 times on Facebook and Twitter. Most designers–voters reported that they participated to contribute to an important cause (44%) rather than to win money (0.8%). Design themes included: empowerment, location awareness, objects (e.g., wings, lightning, batteries, lifebuoys), and others. Conclusions. The Defibrillator Design Challenge engaged a broad audience to generate AED designs and foster awareness. This project provides a framework for using design and contest architecture to promote health messages. PMID:25320902

Design Process of Flight Vehicle Structures for a Common Bulkhead and an MPCV Spacecraft Adapter

NASA Technical Reports Server (NTRS)

Aggarwal, Pravin; Hull, Patrick V.

2015-01-01

Design and manufacturing space flight vehicle structures is a skillset that has grown considerably at NASA during that last several years. Beginning with the Ares program and followed by the Space Launch System (SLS); in-house designs were produced for both the Upper Stage and the SLS Multipurpose crew vehicle (MPCV) spacecraft adapter. Specifically, critical design review (CDR) level analysis and flight production drawing were produced for the above mentioned hardware. In particular, the experience of this in-house design work led to increased manufacturing infrastructure for both Marshal Space Flight Center (MSFC) and Michoud Assembly Facility (MAF), improved skillsets in both analysis and design, and hands on experience in building and testing (MSA) full scale hardware. The hardware design and development processes from initiation to CDR and finally flight; resulted in many challenges and experiences that produced valuable lessons. This paper builds on these experiences of NASA in recent years on designing and fabricating flight hardware and examines the design/development processes used, as well as the challenges and lessons learned, i.e. from the initial design, loads estimation and mass constraints to structural optimization/affordability to release of production drawing to hardware manufacturing. While there are many documented design processes which a design engineer can follow, these unique experiences can offer insight into designing hardware in current program environments and present solutions to many of the challenges experienced by the engineering team.

On the Materials Science of Nature's Arms Race.

PubMed

Liu, Zengqian; Zhang, Zhefeng; Ritchie, Robert O

2018-06-05

Biological material systems have evolved unique combinations of mechanical properties to fulfill their specific function through a series of ingenious designs. Seeking lessons from Nature by replicating the underlying principles of such biological materials offers new promise for creating unique combinations of properties in man-made systems. One case in point is Nature's means of attack and defense. During the long-term evolutionary "arms race," naturally evolved weapons have achieved exceptional mechanical efficiency with a synergy of effective offense and persistence-two characteristics that often tend to be mutually exclusive in many synthetic systems-which may present a notable source of new materials science knowledge and inspiration. This review categorizes Nature's weapons into ten distinct groups, and discusses the unique structural and mechanical designs of each group by taking representative systems as examples. The approach described is to extract the common principles underlying such designs that could be translated into man-made materials. Further, recent advances in replicating the design principles of natural weapons at differing lengthscales in artificial materials, devices and tools to tackle practical problems are revisited, and the challenges associated with biological and bioinspired materials research in terms of both processing and properties are discussed. © 2018 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

Enhancing astronaut performance using sensorimotor adaptability training

PubMed Central

Bloomberg, Jacob J.; Peters, Brian T.; Cohen, Helen S.; Mulavara, Ajitkumar P.

2015-01-01

Astronauts experience disturbances in balance and gait function when they return to Earth. The highly plastic human brain enables individuals to modify their behavior to match the prevailing environment. Subjects participating in specially designed variable sensory challenge training programs can enhance their ability to rapidly adapt to novel sensory situations. This is useful in our application because we aim to train astronauts to rapidly formulate effective strategies to cope with the balance and locomotor challenges associated with new gravitational environments—enhancing their ability to “learn to learn.” We do this by coupling various combinations of sensorimotor challenges with treadmill walking. A unique training system has been developed that is comprised of a treadmill mounted on a motion base to produce movement of the support surface during walking. This system provides challenges to gait stability. Additional sensory variation and challenge are imposed with a virtual visual scene that presents subjects with various combinations of discordant visual information during treadmill walking. This experience allows them to practice resolving challenging and conflicting novel sensory information to improve their ability to adapt rapidly. Information obtained from this work will inform the design of the next generation of sensorimotor countermeasures for astronauts. PMID:26441561

Enhancing astronaut performance using sensorimotor adaptability training.

PubMed

Bloomberg, Jacob J; Peters, Brian T; Cohen, Helen S; Mulavara, Ajitkumar P

2015-01-01

Astronauts experience disturbances in balance and gait function when they return to Earth. The highly plastic human brain enables individuals to modify their behavior to match the prevailing environment. Subjects participating in specially designed variable sensory challenge training programs can enhance their ability to rapidly adapt to novel sensory situations. This is useful in our application because we aim to train astronauts to rapidly formulate effective strategies to cope with the balance and locomotor challenges associated with new gravitational environments-enhancing their ability to "learn to learn." We do this by coupling various combinations of sensorimotor challenges with treadmill walking. A unique training system has been developed that is comprised of a treadmill mounted on a motion base to produce movement of the support surface during walking. This system provides challenges to gait stability. Additional sensory variation and challenge are imposed with a virtual visual scene that presents subjects with various combinations of discordant visual information during treadmill walking. This experience allows them to practice resolving challenging and conflicting novel sensory information to improve their ability to adapt rapidly. Information obtained from this work will inform the design of the next generation of sensorimotor countermeasures for astronauts.

Bridging the Chasm: Challenges, Opportunities, and Resources for Integrating a Dissemination and Implementation Science Curriculum into Medical Education.

PubMed

Ginossar, Tamar; Heckman, Carolyn J; Cragun, Deborah; Quintiliani, Lisa M; Proctor, Enola K; Chambers, David A; Skolarus, Ted; Brownson, Ross C

2018-01-01

Physicians are charged with implementing evidence-based medicine, yet few are trained in the science of Dissemination and Implementation (D&I). In view of the potential of evidence-based training in D&I to help close the gap between research and practice, the goal of this review is to examine the importance of D&I training in medical education, describe challenges to implementing such training, and provide strategies and resources for building D&I capacity. We conducted (1) a systematic review to identify US-based D&I training efforts and (2) a critical review of additional literature to inform our evaluation of the challenges and opportunities of integrating D&I training in medical education. Out of 269 unique articles reviewed, 11 described US-based D&I training. Although vibrant and diverse training opportunities exist, their capacity is limited, and they are not designed to meet physicians' needs. Synthesis of relevant literature using a critical review approach identified challenges inherent to changing medical education, as well as challenges related to D&I science. Finally, selected strategies and resources are available for facilitating incorporation of D&I training into medical education and overcoming existing challenges. Integrating D&I training in the medical education curriculum, and particularly in residency and fellowship training, holds promise for bridging the chasm between scientific discoveries and improved patient care and outcomes. However, unique challenges should be addressed, including the need for greater evidence.

Design of a High Temperature Radiator for the Variable Specific Impulse Magnetoplasma Rocket

NASA Technical Reports Server (NTRS)

Sheth, Rubik B.; Ungar, Eugene K.; Chambliss, Joe P.

2012-01-01

The Variable Specific Impulse Magnetoplasma Rocket (VASIMR), currently under development by Ad Astra Rocket Company (Webster, TX), is a unique propulsion system that could change the way space propulsion is performed. VASIMR's efficiency, when compared to that of a conventional chemical rocket, reduces the propellant needed for exploration missions by a factor of 10. Currently plans include flight tests of a 200 kW VASIMR system, titled VF-200, on the International Space Station (ISS). The VF-200 will consist of two 100 kW thruster units packaged together in one engine bus. Each thruster core generates 27 kW of waste heat during its 15 minute firing time. The rocket core will be maintained between 283 and 573 K by a pumped thermal control loop. The design of a high temperature radiator is a unique challenge for the vehicle design. This paper will discuss the path taken to develop a steady state and transient-based radiator design. The paper will describe the radiator design option selected for the VASIMR thermal control system for use on ISS, and how the system relates to future exploration vehicles.

Rewards and unique challenges faced by African-American custodial grandmothers: the importance of future planning.

PubMed

Crowther, Martha R; Huang, Chao-Hui Sylvia; Allen, Rebecca S

2015-01-01

This exploratory study examined the context and consequences of custodial grandparenting, along with attitudes and preferences regarding future planning among 22 African-American custodial grandmothers. A mixed-method research design was employed. Based on our integration of two theories regarding future planning and health behavior change, caregiving, emotional distress, religiosity and spirituality, and future planning were assessed using questionnaires along with semi-structured interviews. African-American custodial grandmothers (mean age M = 53.64, SD = 9.58) perceived their caregiving role as rewarding (72%) yet challenging (86%). More than 40% reported significant emotional distress (CES-D ≥ 16) that warrants clinical attention. Findings showed that while 64% of study participants had future plans regarding who will substitute in their caregiving role if they become incapacitated, only 9% had completed a living will. Three major themes emerged regarding custodial grandmothers' caregiving role which includes: (1) rewards; (2) challenges including feeling overwhelmed and health concerns; and (3) caregiving decisions including conflicts between 'My plan was…/put self on-hold' for grandchildren and difficulty with future planning. These themes highlighted the dynamics of caregiving across time, including current context and the ongoing process of decision-making. Findings suggest that while African-American custodial grandmothers find caregiving rewarding, they face unique challenges in contemplating and developing future plans. Custodial grandmothers think about substitute caregivers for their grandchildren but need assistance communicating a plan focused on their own needs for future care. Culturally sensitive interventions designed to facilitate effective utilization of future plans within this caregiver population are needed.

Microfluidic point-of-care diagnostics for resource-poor environments

NASA Astrophysics Data System (ADS)

Laksanasopin, Tassaneewan; Chin, Curtis D.; Moore, Hannah; Wang, Jennifer; Cheung, Yuk Kee; Sia, Samuel K.

2009-05-01

Point-of-care (POC) diagnostics have tremendous potential to improve human health in remote and resource-poor settings. However, the design criteria for diagnostic tests appropriate in settings with limited infrastructure are unique and challenging. Here we present a custom optical reader which quantifies silver absorbance from heterogeneous immunoassays. The reader is simple and low-cost and suited for POC diagnostics.

Wood-based Tri-Axial Sandwich Composite Materials: Design, Fabrication, Testing, Modeling and Application

Treesearch

Jinghao Li; John F. Hunt; Shaoqin Gong; Zhiyong Cai

2014-01-01

As the demand for sustainable materials increases, there are unique challenges and opportunities to develop light-weight green composites materials for a wide range of applications. Thus wood-based composite materials from renewable forests may provide options for some niche applications while helping to protect our environment. In this paper, the wood-based tri-axial...

Using Blended Learning Strategies to Address Teaching Development Needs: How Does Canada Compare?

ERIC Educational Resources Information Center

Kanuka, Heather; Rourke, Liam

2013-01-01

The provision of blended learning strategies designed to assist academics in the higher education sector with the knowledge, skills, and abilities required for effective teaching with technology has been, and continues to be, a challenge for teaching centres in Canada. It is unclear, first, whether this is an ongoing issue unique to Canada; and,…

Hearing Parents' Appraisals of Parenting a Deaf or Hard-of-Hearing Child: Application of a Positive Psychology Framework

ERIC Educational Resources Information Center

Szarkowski, Amy; Brice, Patrick J.

2016-01-01

Hearing parents of deaf and hard-of-hearing children face unique challenges and stressors, the understanding of which has been the focus of numerous studies; yet, relatively little is known about their positive experiences. Using a qualitative purposive sampling design, interviews were conducted with 11 hearing parents (8 mothers, 3 fathers)…

Every Drop Counts: Students Develop Public Service Announcements on the Importance of Water Conservation

ERIC Educational Resources Information Center

Stokes, Nina Christiane; Hull, Mary Margaret

2002-01-01

In today's fast-paced, technological world, it is a constant battle for teachers to find new and exciting ways to challenge and engage their students. One success story involves a unique collaborative project that focuses on water resources and conservation in which students design public service announcements (PSAs) to be produced and aired on…

Quality Child Care for Infants and Toddlers: Case Studies of Three Community Strategies. Final Report.

ERIC Educational Resources Information Center

Paulsell, Diane; Nogales, Renee; Cohen, Julie

To address the increasing child care needs of low-income families in the wake of welfare reform, federal and state governments have responded with increased funding for child care and for initiatives to improve quality. Some of these initiatives have been designed specifically to address the unique challenges of infant-toddler care. This report…

Refractive and relativistic effects on ITER low field side reflectometer design.

PubMed

Wang, G; Rhodes, T L; Peebles, W A; Harvey, R W; Budny, R V

2010-10-01

The ITER low field side reflectometer faces some unique design challenges, among which are included the effect of relativistic electron temperatures and refraction of probing waves. This paper utilizes GENRAY, a 3D ray tracing code, to investigate these effects. Using a simulated ITER operating scenario, characteristics of the reflected millimeter waves after return to the launch plane are quantified as a function of a range of design parameters, including antenna height, antenna diameter, and antenna radial position. Results for edge/SOL measurement with both O- and X-mode polarizations using proposed antennas are reported.

International Space Station Passive Thermal Control System Analysis, Top Ten Lessons-Learned

NASA Technical Reports Server (NTRS)

Iovine, John

2011-01-01

The International Space Station (ISS) has been on-orbit for over 10 years, and there have been numerous technical challenges along the way from design to assembly to on-orbit anomalies and repairs. The Passive Thermal Control System (PTCS) management team has been a key player in successfully dealing with these challenges. The PTCS team performs thermal analysis in support of design and verification, launch and assembly constraints, integration, sustaining engineering, failure response, and model validation. This analysis is a significant body of work and provides a unique opportunity to compile a wealth of real world engineering and analysis knowledge and the corresponding lessons-learned. The analysis lessons encompass the full life cycle of flight hardware from design to on-orbit performance and sustaining engineering. These lessons can provide significant insight for new projects and programs. Key areas to be presented include thermal model fidelity, verification methods, analysis uncertainty, and operations support.

Brush Seals for Improved Steam Turbine Performance

NASA Technical Reports Server (NTRS)

Turnquist, Norman; Chupp, Ray; Baily, Fred; Burnett, Mark; Rivas, Flor; Bowsher, Aaron; Crudgington, Peter

2006-01-01

GE Energy has retrofitted brush seals into more than 19 operating steam turbines. Brush seals offer superior leakage control compared to labyrinth seals, owing to their compliant nature and ability to maintain very tight clearances to the rotating shaft. Seal designs have been established for steam turbines ranging in size from 12 MW to over 1200 MW, including fossil, nuclear, combined-cycle and industrial applications. Steam turbines present unique design challenges that must be addressed to ensure that the potential performance benefits of brush seals are realized. Brush seals can have important effects on the overall turbine system that must be taken into account to assure reliable operation. Subscale rig tests are instrumental to understanding seal behavior under simulated steam-turbine operating conditions, prior to installing brush seals in the field. This presentation discusses the technical challenges of designing brush seals for steam turbines; subscale testing; performance benefits of brush seals; overall system effects; and field applications.

A predictive machine learning approach for microstructure optimization and materials design

NASA Astrophysics Data System (ADS)

Liu, Ruoqian; Kumar, Abhishek; Chen, Zhengzhang; Agrawal, Ankit; Sundararaghavan, Veera; Choudhary, Alok

2015-06-01

This paper addresses an important materials engineering question: How can one identify the complete space (or as much of it as possible) of microstructures that are theoretically predicted to yield the desired combination of properties demanded by a selected application? We present a problem involving design of magnetoelastic Fe-Ga alloy microstructure for enhanced elastic, plastic and magnetostrictive properties. While theoretical models for computing properties given the microstructure are known for this alloy, inversion of these relationships to obtain microstructures that lead to desired properties is challenging, primarily due to the high dimensionality of microstructure space, multi-objective design requirement and non-uniqueness of solutions. These challenges render traditional search-based optimization methods incompetent in terms of both searching efficiency and result optimality. In this paper, a route to address these challenges using a machine learning methodology is proposed. A systematic framework consisting of random data generation, feature selection and classification algorithms is developed. Experiments with five design problems that involve identification of microstructures that satisfy both linear and nonlinear property constraints show that our framework outperforms traditional optimization methods with the average running time reduced by as much as 80% and with optimality that would not be achieved otherwise.

Environmental design implications for two deep space SmallSats

NASA Astrophysics Data System (ADS)

Kahn, Peter; Imken, Travis; Elliott, John; Sherwood, Brent; Frick, Andreas; Sheldon, Douglas; Lunine, Jonathan

2017-10-01

The extreme environmental challenges of deep space exploration force unique solutions to small satellite design in order to enable their use as scientifically viable spacecraft. The challenges of implementing small satellites within limited resources can be daunting when faced with radiation effects on delicate electronics that require shielding or unique adaptations for protection, or mass, power and volume limitations due to constraints placed by the carrier spacecraft, or even Planetary Protection compliant design techniques that drive assembly and testing. This paper will explore two concept studies where the environmental constraints and/or planetary protection mitigations drove the design of the Flight System. The paper will describe the key technical drivers on the Sylph mission concept to explore a plume at Europa as a secondary free-flyer as a part of the planned Europa Mission. Sylph is a radiation-hardened smallsat concept that would utilize terrain relative navigation to fly at low altitudes through a plume, if found, and relay the mass spectra data back through the flyby spacecraft during its 24-h mission. The second topic to be discussed will be the mission design constraints of the Near Earth Asteroid (NEA) Scout concept. NEAScout is a 6U cubesat that would utilize an 86 sq. m solar sail as propulsion to execute a flyby with a near-Earth asteroid and help retire Strategic Knowledge Gaps for future human exploration. NEAScout would cruise for 24 months to reach and characterize one Near-Earth asteroid that is representative of Human Exploration targets and telemeter that data directly back to Earth at the end of its roughly 2.5 year mission.

Sample Returns Missions in the Coming Decade

NASA Technical Reports Server (NTRS)

Desai, Prasun N.; Mitcheltree, Robert A.; Cheatwood, F. McNeil

2000-01-01

In the coming decade, several missions will attempt to return samples to Earth from varying parts of the solar system. These samples will provide invaluable insight into the conditions present during the early formation of the solar system, and possibly give clues to how life began on Earth. A description of five sample return missions is presented (Stardust, Genesis, Muses-C. Mars Sample Return, and Comet Nucleus Sample Return). An overview of each sample return mission is given, concentrating particularly on the technical challenges posed during the Earth entry, descent, and landing phase of the missions. Each mission faces unique challenges in the design of an Earth entry capsule. The design of the entry capsule must address the aerodynamic, heating, deceleration, landing, and recovery requirements for the safe return of samples to Earth.

Design and implementation of a secure wireless mote-based medical sensor network.

PubMed

Malasri, Kriangsiri; Wang, Lan

2009-01-01

A medical sensor network can wirelessly monitor vital signs of humans, making it useful for long-term health care without sacrificing patient comfort and mobility. For such a network to be viable, its design must protect data privacy and authenticity given that medical data are highly sensitive. We identify the unique security challenges of such a sensor network and propose a set of resource-efficient mechanisms to address these challenges. Our solution includes (1) a novel two-tier scheme for verifying the authenticity of patient data, (2) a secure key agreement protocol to set up shared keys between sensor nodes and base stations, and (3) symmetric encryption/decryption for protecting data confidentiality and integrity. We have implemented the proposed mechanisms on a wireless mote platform, and our results confirm their feasibility.

Nanomedicine applications in orthopedic medicine: state of the art

PubMed Central

Mazaheri, Mozhdeh; Eslahi, Niloofar; Ordikhani, Farideh; Tamjid, Elnaz; Simchi, Abdolreza

2015-01-01

The technological and clinical need for orthopedic replacement materials has led to significant advances in the field of nanomedicine, which embraces the breadth of nanotechnology from pharmacological agents and surface modification through to regulation and toxicology. A variety of nanostructures with unique chemical, physical, and biological properties have been engineered to improve the functionality and reliability of implantable medical devices. However, mimicking living bone tissue is still a challenge. The scope of this review is to highlight the most recent accomplishments and trends in designing nanomaterials and their applications in orthopedics with an outline on future directions and challenges. PMID:26451110

Nanomedicine applications in orthopedic medicine: state of the art.

PubMed

Mazaheri, Mozhdeh; Eslahi, Niloofar; Ordikhani, Farideh; Tamjid, Elnaz; Simchi, Abdolreza

2015-01-01

The technological and clinical need for orthopedic replacement materials has led to significant advances in the field of nanomedicine, which embraces the breadth of nanotechnology from pharmacological agents and surface modification through to regulation and toxicology. A variety of nanostructures with unique chemical, physical, and biological properties have been engineered to improve the functionality and reliability of implantable medical devices. However, mimicking living bone tissue is still a challenge. The scope of this review is to highlight the most recent accomplishments and trends in designing nanomaterials and their applications in orthopedics with an outline on future directions and challenges.

Fusion power: a challenge for materials science.

PubMed

Duffy, D M

2010-07-28

The selection and design of materials that will withstand the extreme conditions of a fusion power plant has been described as one of the greatest materials science challenges in history. The high particle flux, high thermal load, thermal mechanical stress and the production of transmutation elements combine to produce a uniquely hostile environment. In this paper, the materials favoured for the diverse roles in a fusion power plant are discussed, along with the experimental and modelling techniques that are used to advance the understanding of radiation damage in materials. Areas where further research is necessary are highlighted.

Collusion-resistant multimedia fingerprinting: a unified framework

NASA Astrophysics Data System (ADS)

Wu, Min; Trappe, Wade; Wang, Z. Jane; Liu, K. J. Ray

2004-06-01

Digital fingerprints are unique labels inserted in different copies of the same content before distribution. Each digital fingerprint is assigned to an inteded recipient, and can be used to trace the culprits who use their content for unintended purposes. Attacks mounted by multiple users, known as collusion attacks, provide a cost-effective method for attenuating the identifying fingerprint from each coluder, thus collusion poses a reeal challenge to protect the digital media data and enforce usage policies. This paper examines a few major design methodologies for collusion-resistant fingerprinting of multimedia, and presents a unified framework that helps highlight the common issues and the uniqueness of different fingerprinting techniques.

Space station operations management

NASA Technical Reports Server (NTRS)

Cannon, Kathleen V.

1989-01-01

Space Station Freedom operations management concepts must be responsive to the unique challenges presented by the permanently manned international laboratory. Space Station Freedom will be assembled over a three year period where the operational environment will change as significant capability plateaus are reached. First Element Launch, Man-Tended Capability, and Permanent Manned Capability, represent milestones in operational capability that is increasing toward mature operations capability. Operations management concepts are being developed to accomodate the varying operational capabilities during assembly, as well as the mature operational environment. This paper describes operations management concepts designed to accomodate the uniqueness of Space Station Freedoom, utilizing tools and processes that seek to control operations costs.

Programmable self-assembly of three-dimensional nanostructures from 10,000 unique components

NASA Astrophysics Data System (ADS)

Ong, Luvena L.; Hanikel, Nikita; Yaghi, Omar K.; Grun, Casey; Strauss, Maximilian T.; Bron, Patrick; Lai-Kee-Him, Josephine; Schueder, Florian; Wang, Bei; Wang, Pengfei; Kishi, Jocelyn Y.; Myhrvold, Cameron; Zhu, Allen; Jungmann, Ralf; Bellot, Gaetan; Ke, Yonggang; Yin, Peng

2017-12-01

Nucleic acids (DNA and RNA) are widely used to construct nanometre-scale structures with ever increasing complexity, with possible application in fields such as structural biology, biophysics, synthetic biology and photonics. The nanostructures are formed through one-pot self-assembly, with early kilodalton-scale examples containing typically tens of unique DNA strands. The introduction of DNA origami, which uses many staple strands to fold one long scaffold strand into a desired structure, has provided access to megadalton-scale nanostructures that contain hundreds of unique DNA strands. Even larger DNA origami structures are possible, but manufacturing and manipulating an increasingly long scaffold strand remains a challenge. An alternative and more readily scalable approach involves the assembly of DNA bricks, which each consist of four short binding domains arranged so that the bricks can interlock. This approach does not require a scaffold; instead, the short DNA brick strands self-assemble according to specific inter-brick interactions. First-generation bricks used to create three-dimensional structures are 32 nucleotides long, consisting of four eight-nucleotide binding domains. Protocols have been designed to direct the assembly of hundreds of distinct bricks into well formed structures, but attempts to create larger structures have encountered practical challenges and had limited success. Here we show that DNA bricks with longer, 13-nucleotide binding domains make it possible to self-assemble 0.1-1-gigadalton, three-dimensional nanostructures from tens of thousands of unique components, including a 0.5-gigadalton cuboid containing about 30,000 unique bricks and a 1-gigadalton rotationally symmetric tetramer. We also assembled a cuboid that contains around 10,000 bricks and about 20,000 uniquely addressable, 13-base-pair ‘voxels’ that serves as a molecular canvas for three-dimensional sculpting. Complex, user-prescribed, three-dimensional cavities can be produced within this molecular canvas, enabling the creation of shapes such as letters, a helicoid and a teddy bear. We anticipate that with further optimization of structure design, strand synthesis and assembly procedure even larger structures could be accessible, which could be useful for applications such as positioning functional components.

Mother-Daughter Dyad Recruitment and Cancer Intervention Challenges in an African American Sample

PubMed Central

Mosavel, Maghboeba; Ports, Katie; Leighton-Herrmann, Ellyn

2014-01-01

Developing an effective youth-based health messaging intervention for African American women, who remain disparately impacted by cancer, presents unique challenges. This paper reports on the challenges with recruiting familial dyads from predominantly low-income, African American neighborhoods, as well as the challenges associated with designing and implementing an upward-directed cancer screening intervention. We developed and pilot tested an educational workshop that provided adolescents with cancer screening information to share with their mother or female relative. Data from follow-up interviews and focus groups, as well as observation records regarding implementation obstacles highlight important lessons learned. The use of familial dyads as well as issues of access posed challenges for recruitment and follow-up. Workshop-related challenges stemmed from the approach, content and length. Finally, personal and environmental factors presented barriers to adolescent message delivery and adult follow-through. By identifying these challenges, we hope to influence and enable the future development of effective adolescent-initiated health messaging interventions. PMID:25489496

Navigating complex sample analysis using national survey data.

PubMed

Saylor, Jennifer; Friedmann, Erika; Lee, Hyeon Joo

2012-01-01

The National Center for Health Statistics conducts the National Health and Nutrition Examination Survey and other national surveys with probability-based complex sample designs. Goals of national surveys are to provide valid data for the population of the United States. Analyses of data from population surveys present unique challenges in the research process but are valuable avenues to study the health of the United States population. The aim of this study was to demonstrate the importance of using complex data analysis techniques for data obtained with complex multistage sampling design and provide an example of analysis using the SPSS Complex Samples procedure. Illustration of challenges and solutions specific to secondary data analysis of national databases are described using the National Health and Nutrition Examination Survey as the exemplar. Oversampling of small or sensitive groups provides necessary estimates of variability within small groups. Use of weights without complex samples accurately estimates population means and frequency from the sample after accounting for over- or undersampling of specific groups. Weighting alone leads to inappropriate population estimates of variability, because they are computed as if the measures were from the entire population rather than a sample in the data set. The SPSS Complex Samples procedure allows inclusion of all sampling design elements, stratification, clusters, and weights. Use of national data sets allows use of extensive, expensive, and well-documented survey data for exploratory questions but limits analysis to those variables included in the data set. The large sample permits examination of multiple predictors and interactive relationships. Merging data files, availability of data in several waves of surveys, and complex sampling are techniques used to provide a representative sample but present unique challenges. In sophisticated data analysis techniques, use of these data is optimized.

Performing skin microbiome research: A method to the madness

PubMed Central

Kong, Heidi H.; Andersson, Björn; Clavel, Thomas; Common, John E.; Jackson, Scott A.; Olson, Nathan D.; Segre, Julia A.; Traidl-Hoffmann, Claudia

2017-01-01

Growing interest in microbial contributions to human health and disease has increasingly led investigators to examine the microbiome in both healthy skin and cutaneous disorders, including acne, psoriasis and atopic dermatitis. The need for common language, effective study design, and validated methods are critical for high-quality, standardized research. Features, unique to skin, pose particular challenges when conducting microbiome research. This review discusses microbiome research standards and highlights important factors to consider, including clinical study design, skin sampling, sample processing, DNA sequencing, control inclusion, and data analysis. PMID:28063650

DAnTE: a statistical tool for quantitative analysis of –omics data

DOE Office of Scientific and Technical Information (OSTI.GOV)

Polpitiya, Ashoka D.; Qian, Weijun; Jaitly, Navdeep

2008-05-03

DAnTE (Data Analysis Tool Extension) is a statistical tool designed to address challenges unique to quantitative bottom-up, shotgun proteomics data. This tool has also been demonstrated for microarray data and can easily be extended to other high-throughput data types. DAnTE features selected normalization methods, missing value imputation algorithms, peptide to protein rollup methods, an extensive array of plotting functions, and a comprehensive ANOVA scheme that can handle unbalanced data and random effects. The Graphical User Interface (GUI) is designed to be very intuitive and user friendly.

Autonomous Experimentation of Carbon Nanotube Using Response Surface Methods

DTIC Science & Technology

2015-03-26

on the unique challenges of creating autonomous research robots . v Table of Contents Page Abstract...previous RSM results. 31 S AR Reset a l data les Disp ay Sta t Menu Adjust eas ble bounda es Ad ust acto evel size Dec de andom o speci ed n t...al sta t ni ial Sta t Gene ate andom sta t # o uns D splay O Block Menu C ea e O B ock des gn Disp ay ull O Design Menu C ea e O ull Design W

Algorithms and Array Design Criteria for Robust Imaging in Interferometry

NASA Astrophysics Data System (ADS)

Kurien, Binoy George

Optical interferometry is a technique for obtaining high-resolution imagery of a distant target by interfering light from multiple telescopes. Image restoration from interferometric measurements poses a unique set of challenges. The first challenge is that the measurement set provides only a sparse-sampling of the object's Fourier Transform and hence image formation from these measurements is an inherently ill-posed inverse problem. Secondly, atmospheric turbulence causes severe distortion of the phase of the Fourier samples. We develop array design conditions for unique Fourier phase recovery, as well as a comprehensive algorithmic framework based on the notion of redundant-spaced-calibration (RSC), which together achieve reliable image reconstruction in spite of these challenges. Within this framework, we see that classical interferometric observables such as the bispectrum and closure phase can limit sensitivity, and that generalized notions of these observables can improve both theoretical and empirical performance. Our framework leverages techniques from lattice theory to resolve integer phase ambiguities in the interferometric phase measurements, and from graph theory, to select a reliable set of generalized observables. We analyze the expected shot-noise-limited performance of our algorithm for both pairwise and Fizeau interferometric architectures and corroborate this analysis with simulation results. We apply techniques from the field of compressed sensing to perform image reconstruction from the estimates of the object's Fourier coefficients. The end result is a comprehensive strategy to achieve well-posed and easily-predictable reconstruction performance in optical interferometry.

CosmoQuest: A Cyber-Infrastructure for Crowdsourcing Planetary Surface Mapping and More

NASA Astrophysics Data System (ADS)

Gay, P.; Lehan, C.; Moore, J.; Bracey, G.; Gugliucci, N.

2014-04-01

The design and implementation of programs to crowdsource science presents a unique set of challenges to system architects, programmers, and designers. The CosmoQuest Citizen Science Builder (CSB) is an open source platform designed to take advantage of crowd computing and open source platforms to solve crowdsourcing problems in Planetary Science. CSB combines a clean user interface with a powerful back end to allow the quick design and deployment of citizen science sites that meet the needs of both the random Joe Public, and the detail driven Albert Professional. In this talk, the software will be overviewed, and the results of usability testing and accuracy testing with both citizen and professional scientists will be discussed.

Big Science, Small-Budget Space Experiment Package Aka MISSE-5: A Hardware And Software Perspective

NASA Technical Reports Server (NTRS)

Krasowski, Michael; Greer, Lawrence; Flatico, Joseph; Jenkins, Phillip; Spina, Dan

2007-01-01

Conducting space experiments with small budgets is a fact of life for many design groups with low-visibility science programs. One major consequence is that specialized space grade electronic components are often too costly to incorporate into the design. Radiation mitigation now becomes more complex as a result of being restricted to the use of commercial off-the-shelf (COTS) parts. Unique hardware and software design techniques are required to succeed in producing a viable instrument suited for use in space. This paper highlights some of the design challenges and associated solutions encountered in the production of a highly capable, low cost space experiment package.

A Hardware and Software Perspective of the Fifth Materials on the International Space Station Experiment (MISSE-5)

NASA Technical Reports Server (NTRS)

Krasowski, Michael; Greer, Lawrence; Flatico, Joseph; Jenkins, Phillip; Spina, Dan

2005-01-01

Conducting space experiments with small budgets is a fact of life for many design groups with low-visibility science programs. One major consequence is that specialized space grade electronic components are often too costly to incorporate into the design. Radiation mitigation now becomes more complex as a result of being restricted to the use of commercial off-the-shelf (COTS) parts. Unique hardware and software design techniques are required to succeed in producing a viable instrument suited for use in space. This paper highlights some of the design challenges and associated solutions encountered in the production of a highly capable, low cost space experiment package.

Design and Analysis of Offshore Macroalgae Biorefineries.

PubMed

Golberg, Alexander; Liberzon, Alexander; Vitkin, Edward; Yakhini, Zohar

2018-03-15

Displacing fossil fuels and their derivatives with renewables, and increasing sustainable food production are among the major challenges facing the world in the coming decades. A possible, sustainable direction for addressing this challenge is the production of biomass and the conversion of this biomass to the required products through a complex system coined biorefinery. Terrestrial biomass and microalgae are possible sources; however, concerns over net energy balance, potable water use, environmental hazards, and uncertainty in the processing technologies raise questions regarding their actual potential to meet the anticipated food, feed, and energy challenges in a sustainable way. Alternative sustainable sources for biorefineries are macroalgae grown and processed offshore. However, implementation of the offshore biorefineries requires detailed analysis of their technological, economic, and environmental performance. In this chapter, the basic principles of marine biorefineries design are shown. The methods to integrate thermodynamic efficiency, investment, and environmental aspects are discussed. The performance improvement by development of new cultivation methods that fit macroalgae physiology and development of new fermentation methods that address macroalgae unique chemical composition is shown.

Early phase clinical trials with human immunodeficiency virus-1 and malaria vectored vaccines in The Gambia: frontline challenges in study design and implementation.

PubMed

Afolabi, Muhammed O; Adetifa, Jane U; Imoukhuede, Egeruan B; Viebig, Nicola K; Kampmann, Beate; Bojang, Kalifa

2014-05-01

Human immunodeficiency virus/acquired immune deficiency syndrome (HIV/AIDS) and malaria are among the most important infectious diseases in developing countries. Existing control strategies are unlikely to curtail these diseases in the absence of efficacious vaccines. Testing of HIV and malaria vaccines candidates start with early phase trials that are increasingly being conducted in developing countries where the burden of the diseases is high. Unique challenges, which affect planning and implementation of vaccine trials according to internationally accepted standards have thus been identified. In this review, we highlight specific challenges encountered during two early phase trials of novel HIV-1 and malaria vectored vaccine candidates conducted in The Gambia and how some of these issues were pragmatically addressed. We hope our experience will be useful for key study personnel involved in day-to-day running of similar clinical trials. It may also guide future design and implementation of vaccine trials in resource-constrained settings.

Design and Control of Compliant Tensegrity Robots Through Simulation and Hardware Validation

NASA Technical Reports Server (NTRS)

Caluwaerts, Ken; Despraz, Jeremie; Iscen, Atil; Sabelhaus, Andrew P.; Bruce, Jonathan; Schrauwen, Benjamin; Sunspiral, Vytas

2014-01-01

To better understand the role of tensegrity structures in biological systems and their application to robotics, the Dynamic Tensegrity Robotics Lab at NASA Ames Research Center has developed and validated two different software environments for the analysis, simulation, and design of tensegrity robots. These tools, along with new control methodologies and the modular hardware components developed to validate them, are presented as a system for the design of actuated tensegrity structures. As evidenced from their appearance in many biological systems, tensegrity ("tensile-integrity") structures have unique physical properties which make them ideal for interaction with uncertain environments. Yet these characteristics, such as variable structural compliance, and global multi-path load distribution through the tension network, make design and control of bio-inspired tensegrity robots extremely challenging. This work presents the progress in using these two tools in tackling the design and control challenges. The results of this analysis includes multiple novel control approaches for mobility and terrain interaction of spherical tensegrity structures. The current hardware prototype of a six-bar tensegrity, code-named ReCTeR, is presented in the context of this validation.

The space shuttle ascent vehicle aerodynamic challenges configuration design and data base development

NASA Technical Reports Server (NTRS)

Dill, C. C.; Young, J. C.; Roberts, B. B.; Craig, M. K.; Hamilton, J. T.; Boyle, W. W.

1985-01-01

The phase B Space Shuttle systems definition studies resulted in a generic configuration consisting of a delta wing orbiter, and two solid rocket boosters (SRB) attached to an external fuel tank (ET). The initial challenge facing the aerodynamic community was aerodynamically optimizing, within limits, this configuration. As the Shuttle program developed and the sensitivities of the vehicle to aerodynamics were better understood the requirements of the aerodynamic data base grew. Adequately characterizing the vehicle to support the various design studies exploded the size of the data base to proportions that created a data modeling/management challenge for the aerodynamicist. The ascent aerodynamic data base originated primarily from wind tunnel test results. The complexity of the configuration rendered conventional analytic methods of little use. Initial wind tunnel tests provided results which included undesirable effects from model support tructure, inadequate element proximity, and inadequate plume simulation. The challenge to improve the quality of test results by determining the extent of these undesirable effects and subsequently develop testing techniques to eliminate them was imposed on the aerodynamic community. The challenges to the ascent aerodynamics community documented are unique due to the aerodynamic complexity of the Shuttle launch. Never before was such a complex vehicle aerodynamically characterized. The challenges were met with innovative engineering analyses/methodology development and wind tunnel testing techniques.

Massachusetts Substance Use Disorder Treatment Organizations’ Perspectives on the Affordable Care Act: Changes in Payment, Services, and System Design

PubMed Central

Quinn, Amity E.; Stewart, Maureen T.; Brolin, Mary; Horgan, Constance; Lane, Nancy E.

2017-01-01

The Affordable Care Act (ACA) expanded insurance benefits and coverage for substance use disorder (SUD) treatment and encouraged delivery and payment reforms. Massachusetts passed a similar reform in 2006. This study aims to assess Massachusetts SUD treatment organizations’ responses to the ACA. Organizational interviews addressing challenges of and responses to the ACA were conducted in-person June–December 2014 with 31 leaders at 12 treatment organizations across Massachusetts. Many organizations were affiliated with medical or social services and offered a range of SUD services. Sampling was based on services offered (detoxification only, detoxification and outpatient, outpatient only). Framework analysis was used. Challenges identified were considered similar to ongoing challenges, not unique to the ACA. Organizations experienced insurance expansions in 2006 and faced new challenges, including insurance coverage, payment arrangements, expansion of services, and system design. System design efforts included care coordination/integration, workforce development, and health information technology. Differences in responses related to connections with medical and social service organizations. Many organizations engaged in efforts to respond to changing policies by expanding capacity and services. Offering a range of SUD treatment (e.g., detoxification and outpatient) and affiliating with a medical organization could enable organizations to respond to new insurance, delivery, and payment reforms. PMID:28350232

The NDCX-II engineering design

NASA Astrophysics Data System (ADS)

Waldron, W. L.; Abraham, W. J.; Arbelaez, D.; Friedman, A.; Galvin, J. E.; Gilson, E. P.; Greenway, W. G.; Grote, D. P.; Jung, J.-Y.; Kwan, J. W.; Leitner, M.; Lidia, S. M.; Lipton, T. M.; Reginato, L. L.; Regis, M. J.; Roy, P. K.; Sharp, W. M.; Stettler, M. W.; Takakuwa, J. H.; Volmering, J.; Vytla, V. K.

2014-01-01

The Neutralized Drift Compression Experiment (NDCX-II) is a user facility located at Lawrence Berkeley National Laboratory which is uniquely designed for ion-beam-driven high energy density laboratory physics and heavy ion fusion research. Construction was completed in March 2012 and the facility is now in the commissioning phase. A significant amount of engineering was carried out in order to meet the performance parameters required for a wide range of target heating experiments while making the most cost-effective use of high-value hardware available from a decommissioned high current electron induction accelerator. The technical challenges and design of this new ion induction accelerator facility are described.

Transforming Teaching Challenges into Learning Opportunities: Interdisciplinary Reflective Collaboration

ERIC Educational Resources Information Center

Callaghan, Ronel

2015-01-01

Teaching in higher education poses unique sets of challenges, especially for academics in the engineering, built sciences and information science education disciplines. This article focuses on how reflective collaboration can support academics in their quest to find unique solutions to challenges in different academic contexts. A reflective…

Cognitive behavioral game design: a unified model for designing serious games

PubMed Central

Starks, Katryna

2014-01-01

Video games have a unique ability to engage, challenge, and motivate, which has led teachers, psychology specialists, political activists and health educators to find ways of using them to help people learn, grow and change. Serious games, as they are called, are defined as games that have a primary purpose other than entertainment. However, it is challenging to create games that both educate and entertain. While game designers have embraced some psychological concepts such as flow and mastery, understanding how these concepts work together within established psychological theory would assist them in creating effective serious games. Similarly, game design professionals have understood the propensity of video games to teach while lamenting that educators do not understand how to incorporate educational principles into game play in a way that preserves the entertainment. Bandura (2006) social cognitive theory (SCT) has been used successfully to create video games that create positive behavior outcomes, and teachers have successfully used Gardner’s (1983) theory of multiple intelligences (MIs) to create engaging, immersive learning experiences. Cognitive behavioral game design is a new framework that incorporates SCT and MI with game design principles to create a game design blueprint for serious games. PMID:24550858

Cognitive behavioral game design: a unified model for designing serious games.

PubMed

Starks, Katryna

2014-01-01

Video games have a unique ability to engage, challenge, and motivate, which has led teachers, psychology specialists, political activists and health educators to find ways of using them to help people learn, grow and change. Serious games, as they are called, are defined as games that have a primary purpose other than entertainment. However, it is challenging to create games that both educate and entertain. While game designers have embraced some psychological concepts such as flow and mastery, understanding how these concepts work together within established psychological theory would assist them in creating effective serious games. Similarly, game design professionals have understood the propensity of video games to teach while lamenting that educators do not understand how to incorporate educational principles into game play in a way that preserves the entertainment. Bandura (2006) social cognitive theory (SCT) has been used successfully to create video games that create positive behavior outcomes, and teachers have successfully used Gardner's (1983) theory of multiple intelligences (MIs) to create engaging, immersive learning experiences. Cognitive behavioral game design is a new framework that incorporates SCT and MI with game design principles to create a game design blueprint for serious games.

Streamlining the Design Tradespace for Earth Imaging Constellations

NASA Technical Reports Server (NTRS)

Nag, Sreeja; Hughes, Steven P.; Le Moigne, Jacqueline J.

2016-01-01

Satellite constellations and Distributed Spacecraft Mission (DSM) architectures offer unique benefits to Earth observation scientists and unique challenges to cost estimators. The Cost and Risk (CR) module of the Tradespace Analysis Tool for Constellations (TAT-C) being developed by NASA Goddard seeks to address some of these challenges by providing a new approach to cost modeling, which aggregates existing Cost Estimating Relationships (CER) from respected sources, cost estimating best practices, and data from existing and proposed satellite designs. Cost estimation through this tool is approached from two perspectives: parametric cost estimating relationships and analogous cost estimation techniques. The dual approach utilized within the TAT-C CR module is intended to address prevailing concerns regarding early design stage cost estimates, and offer increased transparency and fidelity by offering two preliminary perspectives on mission cost. This work outlines the existing cost model, details assumptions built into the model, and explains what measures have been taken to address the particular challenges of constellation cost estimating. The risk estimation portion of the TAT-C CR module is still in development and will be presented in future work. The cost estimate produced by the CR module is not intended to be an exact mission valuation, but rather a comparative tool to assist in the exploration of the constellation design tradespace. Previous work has noted that estimating the cost of satellite constellations is difficult given that no comprehensive model for constellation cost estimation has yet been developed, and as such, quantitative assessment of multiple spacecraft missions has many remaining areas of uncertainty. By incorporating well-established CERs with preliminary approaches to approaching these uncertainties, the CR module offers more complete approach to constellation costing than has previously been available to mission architects or Earth scientists seeking to leverage the capabilities of multiple spacecraft working in support of a common goal.

A Comprehensive Study on the Internet of Underwater Things: Applications, Challenges, and Channel Models †

PubMed Central

Wu, Geng-De; Huang, Chun-Ju

2017-01-01

The Internet of Underwater Things (IoUT) is a novel class of Internet of Things (IoT), and is defined as the network of smart interconnected underwater objects. IoUT is expected to enable various practical applications, such as environmental monitoring, underwater exploration, and disaster prevention. With these applications, IoUT is regarded as one of the potential technologies toward developing smart cities. To support the concept of IoUT, Underwater Wireless Sensor Networks (UWSNs) have emerged as a promising network system. UWSNs are different from the traditional Territorial Wireless Sensor Networks (TWSNs), and have several unique properties, such as long propagation delay, narrow bandwidth, and low reliability. These unique properties would be great challenges for IoUT. In this paper, we provide a comprehensive study of IoUT, and the main contributions of this paper are threefold: (1) we introduce and classify the practical underwater applications that can highlight the importance of IoUT; (2) we point out the differences between UWSNs and traditional TWSNs, and these differences are the main challenges for IoUT; and (3) we investigate and evaluate the channel models, which are the technical core for designing reliable communication protocols on IoUT. PMID:28640220

A Comprehensive Study on the Internet of Underwater Things: Applications, Challenges, and Channel Models.

PubMed

Kao, Chien-Chi; Lin, Yi-Shan; Wu, Geng-De; Huang, Chun-Ju

2017-06-22

The Internet of Underwater Things (IoUT) is a novel class of Internet of Things (IoT), and is defined as the network of smart interconnected underwater objects. IoUT is expected to enable various practical applications, such as environmental monitoring, underwater exploration, and disaster prevention. With these applications, IoUT is regarded as one of the potential technologies toward developing smart cities. To support the concept of IoUT, Underwater Wireless Sensor Networks (UWSNs) have emerged as a promising network system. UWSNs are different from the traditional Territorial Wireless Sensor Networks (TWSNs), and have several unique properties, such as long propagation delay, narrow bandwidth, and low reliability. These unique properties would be great challenges for IoUT. In this paper, we provide a comprehensive study of IoUT, and the main contributions of this paper are threefold: (1) we introduce and classify the practical underwater applications that can highlight the importance of IoUT; (2) we point out the differences between UWSNs and traditional TWSNs, and these differences are the main challenges for IoUT; and (3) we investigate and evaluate the channel models, which are the technical core for designing reliable communication protocols on IoUT.

Evaluation on the Presence of Nano Silver Particle in Improving a Conventional Water-based Drilling Fluid

NASA Astrophysics Data System (ADS)

Husin, H.; Ahmad, N.; Jamil, N.; Chyuan, O. H.; Roslan, A.

2018-05-01

Worldwide demand in oil and gas energy consumption has been driving many of oil and gas companies to explore new oil and gas resource field in an ultra-deep water environment. As deeper well is drilled, more problems and challenges are expected. The successful of drilling operation is highly dependent on properties of drilling fluids. As a way to operate drilling in challenging and extreme surroundings, nanotechnology with their unique properties is employed. Due to unique physicochemical, electrical, thermal, hydrodynamic properties and exceptional interaction potential of nanomaterials, nanoparticles are considered to be the most promising material of choice for smart fluid design for oil and gas field application. Throughout this paper, the effect of nano silver particle in improving a conventional water based drilling fluid was evaluated. Results showed that nano silver gave a significant improvement to the conventional water based drilling fluid in terms of its rheological properties and filtration test performance.

Development and preliminary testing of a web-based, self-help application for disaster-affected families

PubMed Central

Yuen, Erica K; Gros, Kirstin; Welsh, Kyleen E; McCauley, Jenna; Resnick, Heidi S; Danielson, Carla K; Price, Matthew; Ruggiero, Kenneth J

2015-01-01

Technology-based self-help interventions have the potential to increase access to evidence-based mental healthcare, especially for families affected by natural disasters. However, development of these interventions is a complex process and poses unique challenges. Usability testing, which assesses the ability of individuals to use an application successfully, can have a significant impact on the quality of a self-help intervention. This article describes (a) the development of a novel web-based multi-module self-help intervention for disaster-affected adolescents and their parents and (b) a mixed-methods formal usability study to evaluate user response. A total of 24 adolescents were observed, videotaped, and interviewed as they used the depressed mood component of the self-help intervention. Quantitative results indicated an above-average user experience, and qualitative analysis identified 120 unique usability issues. We discuss the challenges of developing self-help applications, including design considerations and the value of usability testing in technology-based interventions, as well as our plan for widespread dissemination. PMID:25933798

Crew Exploration Vehicle Environmental Control and Life Support Fire Protection Approach

NASA Technical Reports Server (NTRS)

Lewis, John F.; Barido, Richard; Tuan, George C.

2007-01-01

As part of preparing for the Crew Exploration Vehicle (CEV), the National Aeronautics and Space Administration (NASA) worked on developing the requirements to manage the fire risk. The new CEV poses unique challenges to current fire protection systems. The size and configuration of the vehicle resembles the Apollo capsule instead of the current Space Shuttle or the International Space Station. The smaller free air volume and fully cold plated avionic bays of the CEV requires a different approach in fire protection than the ones currently utilized. The fire protection approach discussed in this paper incorporates historical lessons learned and fire detection and suppression system design philosophy spanning from Apollo to the International Space Station. Working with NASA fire and materials experts, this approach outlines the best requirements for both the closed out area of the vehicle, such as the avionics bay, and the crew cabin area to address the unique challenges due to the size and configuration of the CEV.

Molecular engineering with artificial atoms: designing a material platform for scalable quantum spintronics and photonics

NASA Astrophysics Data System (ADS)

Doty, Matthew F.; Ma, Xiangyu; Zide, Joshua M. O.; Bryant, Garnett W.

2017-09-01

Self-assembled InAs Quantum Dots (QDs) are often called "artificial atoms" and have long been of interest as components of quantum photonic and spintronic devices. Although there has been substantial progress in demonstrating optical control of both single spins confined to a single QD and entanglement between two separated QDs, the path toward scalable quantum photonic devices based on spins remains challenging. Quantum Dot Molecules, which consist of two closely-spaced InAs QDs, have unique properties that can be engineered with the solid state analog of molecular engineering in which the composition, size, and location of both the QDs and the intervening barrier are controlled during growth. Moreover, applied electric, magnetic, and optical fields can be used to modulate, in situ, both the spin and optical properties of the molecular states. We describe how the unique photonic properties of engineered Quantum Dot Molecules can be leveraged to overcome long-standing challenges to the creation of scalable quantum devices that manipulate single spins via photonics.

Using Quantum Confinement to Uniquely Identify Devices

PubMed Central

Roberts, J.; Bagci, I. E.; Zawawi, M. A. M.; Sexton, J.; Hulbert, N.; Noori, Y. J.; Young, M. P.; Woodhead, C. S.; Missous, M.; Migliorato, M. A.; Roedig, U.; Young, R. J.

2015-01-01

Modern technology unintentionally provides resources that enable the trust of everyday interactions to be undermined. Some authentication schemes address this issue using devices that give a unique output in response to a challenge. These signatures are generated by hard-to-predict physical responses derived from structural characteristics, which lend themselves to two different architectures, known as unique objects (UNOs) and physically unclonable functions (PUFs). The classical design of UNOs and PUFs limits their size and, in some cases, their security. Here we show that quantum confinement lends itself to the provision of unique identities at the nanoscale, by using fluctuations in tunnelling measurements through quantum wells in resonant tunnelling diodes (RTDs). This provides an uncomplicated measurement of identity without conventional resource limitations whilst providing robust security. The confined energy levels are highly sensitive to the specific nanostructure within each RTD, resulting in a distinct tunnelling spectrum for every device, as they contain a unique and unpredictable structure that is presently impossible to clone. This new class of authentication device operates with minimal resources in simple electronic structures above room temperature. PMID:26553435

Design and Development of the Blackbird: Challenges and Lessons Learned

NASA Technical Reports Server (NTRS)

Merlin, Peter W.

2009-01-01

The Lockheed Blackbirds hold a unique place in the development of aeronautics. In their day, the A-12, YF-12, M-21, D-21, and SR-71 variants outperformed all other jet airplanes in terms of altitude and speed. Now retired, they remain the only production aircraft capable of sustained Mach 3 cruise and operational altitudes above 80,000 feet. In this paper the author describes the design evolution of the Blackbird from Lockheed's early Archangel studies for the Central Intelligence Agency through Senior Crown, production of the Air Force's SR-71. He describes the construction and materials challenges faced by Lockheed, the Blackbird's performance characteristics and capabilities, and the National Aeronautics and Space Administration's role in using the aircraft as a flying laboratory to collect data on materials, structures, loads, heating, aerodynamics, and performance for high-speed aircraft.

Design and Implementation of a Secure Wireless Mote-Based Medical Sensor Network

PubMed Central

Malasri, Kriangsiri; Wang, Lan

2009-01-01

A medical sensor network can wirelessly monitor vital signs of humans, making it useful for long-term health care without sacrificing patient comfort and mobility. For such a network to be viable, its design must protect data privacy and authenticity given that medical data are highly sensitive. We identify the unique security challenges of such a sensor network and propose a set of resource-efficient mechanisms to address these challenges. Our solution includes (1) a novel two-tier scheme for verifying the authenticity of patient data, (2) a secure key agreement protocol to set up shared keys between sensor nodes and base stations, and (3) symmetric encryption/decryption for protecting data confidentiality and integrity. We have implemented the proposed mechanisms on a wireless mote platform, and our results confirm their feasibility. PMID:22454585

Correctional nursing: a study protocol to develop an educational intervention to optimize nursing practice in a unique context.

PubMed

Almost, Joan; Gifford, Wendy A; Doran, Diane; Ogilvie, Linda; Miller, Crystal; Rose, Don N; Squires, Mae

2013-06-21

Nurses are the primary healthcare providers in correctional facilities. A solid knowledge and expertise that includes the use of research evidence in clinical decision making is needed to optimize nursing practice and promote positive health outcomes within these settings. The institutional emphasis on custodial care within a heavily secured, regulated, and punitive environment presents unique contextual challenges for nursing practice. Subsequently, correctional nurses are not always able to obtain training or ongoing education that is required for broad scopes of practice. The purpose of the proposed study is to develop an educational intervention for correctional nurses to support the provision of evidence-informed care. A two-phase mixed methods research design will be used. The setting will be three provincial correctional facilities. Phase one will focus on identifying nurses' scope of practice and practice needs, describing work environment characteristics that support evidence-informed practice and developing the intervention. Semi-structured interviews will be completed with nurses and nurse managers. To facilitate priorities for the intervention, a Delphi process will be used to rank the learning needs identified by participants. Based on findings, an online intervention will be developed. Phase two will involve evaluating the acceptability and feasibility of the intervention to inform a future experimental design. The context of provincial correctional facilities presents unique challenges for nurses' provision of care. This study will generate information to address practice and learning needs specific to correctional nurses. Interventions tailored to barriers and supports within specific contexts are important to enable nurses to provide evidence-informed care.

Mind the gap: implementation challenges break the link between HIV/AIDS research and practice.

PubMed

MacCarthy, Sarah; Reisner, Sari; Hoffmann, Michael; Perez-Brumer, Amaya; Silva-Santisteban, Alfonso; Nunn, Amy; Bastos, Leonardo; Vasconcellos, Mauricio Teixeira Leite de; Kerr, Ligia; Bastos, Francisco Inácio; Dourado, Inês

2016-11-03

Sampling strategies such as respondent-driven sampling (RDS) and time-location sampling (TLS) offer unique opportunities to access key populations such as men who have sex with men (MSM) and transgender women. Limited work has assessed implementation challenges of these methods. Overcoming implementation challenges can improve research quality and increase uptake of HIV services among key populations. Drawing from studies using RDS in Brazil and TLS in Peru, we summarize challenges encountered in the field and potential strategies to address them. In Brazil, study site selection, cash incentives, and seed selection challenged RDS implementation with MSM. In Peru, expansive geography, safety concerns, and time required for study participation complicated TLS implementation with MSM and transgender women. Formative research, meaningful participation of key populations across stages of research, and transparency in study design are needed to link HIV/AIDS research and practice. Addressing implementation challenges can close gaps in accessing services among those most burdened by the epidemic.

Mind the gap: implementation challenges break the link between HIV/AIDS research and practice

PubMed Central

MacCarthy, Sarah; Reisner, Sari; Hoffmann, Michael; Perez-Brumer, Amaya; Silva-Santisteban, Alfonso; Nunn, Amy; Bastos, Leonardo; de Vasconcellos, Mauricio Teixeira Leite; Kerr, Ligia; Bastos, Francisco Inácio; Dourado, Inês

2018-01-01

Sampling strategies such as respondent-driven sampling (RDS) and time-location sampling (TLS) offer unique opportunities to access key populations such as men who have sex with men (MSM) and transgender women. Limited work has assessed implementation challenges of these methods. Overcoming implementation challenges can improve research quality and increase uptake of HIV services among key populations. Drawing from studies using RDS in Brazil and TLS in Peru, we summarize challenges encountered in the field and potential strategies to address them. In Brazil, study site selection, cash incentives, and seed selection challenged RDS implementation with MSM. In Peru, expansive geography, safety concerns, and time required for study participation complicated TLS implementation with MSM and transgender women. Formative research, meaningful participation of key populations across stages of research, and transparency in study design are needed to link HIV/AIDS research and practice. Addressing implementation challenges can close gaps in accessing services among those most burdened by the epidemic. PMID:27828609

Bringing Person- and Family-Centred Care Alive in Home, Community and Long-Term Care Organizations.

PubMed

Bender, Danielle; Holyoke, Paul

2016-01-01

It is now more important than ever for person- and family-centred care (PFCC) to be at the forefront of program and service design and delivery; yet, to date, very little guidance is available to assist home, community and long-term care (LTC) organizations to operationalize this concept and overcome inherent challenges. This article provides a list of practical strategies for healthcare leaders to promote and support a culture shift towards PFCC in their organizations and identifies and addresses five common concerns. The unique opportunities and challenges for practicing PFCC in home, community and LTC settings are also discussed.

Addressing current challenges in cancer immunotherapy with mathematical and computational modelling.

PubMed

Konstorum, Anna; Vella, Anthony T; Adler, Adam J; Laubenbacher, Reinhard C

2017-06-01

The goal of cancer immunotherapy is to boost a patient's immune response to a tumour. Yet, the design of an effective immunotherapy is complicated by various factors, including a potentially immunosuppressive tumour microenvironment, immune-modulating effects of conventional treatments and therapy-related toxicities. These complexities can be incorporated into mathematical and computational models of cancer immunotherapy that can then be used to aid in rational therapy design. In this review, we survey modelling approaches under the umbrella of the major challenges facing immunotherapy development, which encompass tumour classification, optimal treatment scheduling and combination therapy design. Although overlapping, each challenge has presented unique opportunities for modellers to make contributions using analytical and numerical analysis of model outcomes, as well as optimization algorithms. We discuss several examples of models that have grown in complexity as more biological information has become available, showcasing how model development is a dynamic process interlinked with the rapid advances in tumour-immune biology. We conclude the review with recommendations for modellers both with respect to methodology and biological direction that might help keep modellers at the forefront of cancer immunotherapy development. © 2017 The Author(s).

How Mockups, a Key Engineering Tool, Help to Promote Science, Technology, Engineering, and Mathematics Education

NASA Technical Reports Server (NTRS)

McDonald, Harry E.

2010-01-01

The United States ranking among the world in science, technology, engineering, and mathematics (STEM) education is decreasing. To counteract this problem NASA has made it part of its mission to promote STEM education among the nation s youth. Mockups can serve as a great tool when promoting STEM education in America. The Orion Cockpit Working Group has created a new program called Students Shaping America s Next Space Craft (SSANS) to outfit the Medium Fidelity Orion Mockup. SSANS will challenge the students to come up with unique designs to represent the flight design hardware. There are two main types of project packages created by SSANS, those for high school students and those for university students. The high school projects will challenge wood shop, metal shop and pre-engineering classes. The university projects are created mainly for senior design projects and will require the students to perform finite element analysis. These projects will also challenge the undergraduate students in material selection and safety requirements. The SSANS program will help NASA in its mission to promote STEM education, and will help to shape our nations youth into the next generation of STEM leaders.

Decision making about healthcare-related tests and diagnostic test strategies. Paper 2: a review of methodological and practical challenges.

PubMed

Mustafa, Reem A; Wiercioch, Wojtek; Cheung, Adrienne; Prediger, Barbara; Brozek, Jan; Bossuyt, Patrick; Garg, Amit X; Lelgemann, Monika; Büehler, Diedrich; Schünemann, Holger J

2017-12-01

In this first of a series of five articles, we provide an overview of how and why healthcare-related tests and diagnostic strategies are currently applied. We also describe how our findings can be integrated with existing frameworks for making decisions that guide the use of healthcare-related tests and diagnostic strategies. We searched MEDLINE, references of identified articles, chapters in relevant textbooks, and identified articles citing classic literature on this topic. We provide updated frameworks for the potential roles and applications of tests with suggested definitions and practical examples. We also discuss study designs that are commonly used to assess tests' performance and the effects of tests on people's health. These designs include diagnostic randomized controlled trials and retrospective validation. We describe the utility of these and other currently suggested designs, which questions they can answer and which ones they cannot. In addition, we summarize the challenges unique to decision-making resulting from the use of tests. This overview highlights current challenges in the application of tests in decision-making in healthcare, provides clarifications, and informs the proposed solutions. Copyright © 2017 Elsevier Inc. All rights reserved.

X-33 Attitude Control Using the XRS-2200 Linear Aerospike Engine

NASA Technical Reports Server (NTRS)

Hall, Charles E.; Panossian, Hagop V.

1999-01-01

The Vehicle Control Systems Team at Marshall Space Flight Center, Structures and Dynamics Laboratory, Guidance and Control Systems Division is designing, under a cooperative agreement with Lockheed Martin Skunkworks, the Ascent, Transition, and Entry flight attitude control systems for the X-33 experimental vehicle. Test flights, while suborbital, will achieve sufficient altitudes and Mach numbers to test Single Stage To Orbit, Reusable Launch Vehicle technologies. Ascent flight control phase, the focus of this paper, begins at liftoff and ends at linear aerospike main engine cutoff (MECO). The X-33 attitude control system design is confronted by a myriad of design challenges: a short design cycle, the X-33 incremental test philosophy, the concurrent design philosophy chosen for the X-33 program, and the fact that the attitude control system design is, as usual, closely linked to many other subsystems and must deal with constraints and requirements from these subsystems. Additionally, however, and of special interest, the use of the linear aerospike engine is a departure from the gimbaled engines traditionally used for thrust vector control (TVC) in launch vehicles and poses certain design challenges. This paper discusses the unique problem of designing the X-33 attitude control system with the linear aerospike engine, requirements development, modeling and analyses that verify the design.

Methodological issues in the design and analyses of neonatal research studies: Experience of the NICHD Neonatal Research Network.

PubMed

Das, Abhik; Tyson, Jon; Pedroza, Claudia; Schmidt, Barbara; Gantz, Marie; Wallace, Dennis; Truog, William E; Higgins, Rosemary D

2016-10-01

Impressive advances in neonatology have occurred over the 30 years of life of The Eunice Kennedy Shriver National Institute of Child Health and Human Development Neonatal Research Network (NRN). However, substantial room for improvement remains in investigating and further developing the evidence base for improving outcomes among the extremely premature. We discuss some of the specific methodological challenges in the statistical design and analysis of randomized trials and observational studies in this population. Challenges faced by the NRN include designing trials for unusual or rare outcomes, accounting for and explaining center variations, identifying other subgroup differences, and balancing safety and efficacy concerns between short-term hospital outcomes and longer-term neurodevelopmental outcomes. In conclusion, the constellation of unique patient characteristics in neonates calls for broad understanding and careful consideration of the issues identified in this article for conducting rigorous studies in this population. Copyright © 2016 Elsevier Inc. All rights reserved.

BERLinPro Booster Cavity Design, Fabrication and Test Plans

DOE Office of Scientific and Technical Information (OSTI.GOV)

Burrill, Andrew; Anders, W; Frahm, A.

2014-12-01

The bERLinPro project, a 100 mA, 50 MeV superconducting RF (SRF) Energy Recovery Linac (ERL) is under construction at Helmholtz-Zentrum Berlin for the purpose of studying the technical challenges and physics of operating a high current, c.w., 1.3 GHz ERL. This machine will utilize three unique SRF cryomodules for the injector, booster and linac module respectively. The booster cryomodule will contain three 2-cell SRF cavities, based on the original design by Cornell University, and will be equipped with twin 115 kW RF power couplers in order to provide the appropriate acceleration to the high current electron beam. This paper willmore » review the status of the fabrication of the 4 booster cavities that have been built for this project by Jefferson Laboratory and look at the challenges presented by the incorporation of fundamental power couplers capable of delivering 115 kW. The test plan for the cavities and couplers will be given along with a brief overview of the cryomodule design.« less

Challenges in evaluating cancer as a clinical outcome in postapproval studies of drug safety

PubMed Central

Pinheiro, Simone P.; Rivera, Donna R.; Graham, David J.; Freedman, Andrew N.; Major, Jacqueline M.; Penberthy, Lynne; Levenson, Mark; Bradley, Marie C.; Wong, Hui-Lee; Ouellet-Hellstrom, Rita

2017-01-01

Pharmaceuticals approved in the United States are largely not known human carcinogens. However, cancer signals associated with pharmaceuticals may be hypothesized or arise after product approval. There are many study designs that can be used to evaluate cancer as an outcome in the postapproval setting. Because prospective systematic collection of cancer outcomes from a large number of individuals may be lengthy, expensive, and challenging, leveraging data from large existing databases are an integral approach. Such studies have the capability to evaluate the clinical experience of a large number of individuals, yet there are unique methodological challenges involved in their use to evaluate cancer outcomes. To discuss methodological challenges and potential solutions, the Food and Drug Administration and the National Cancer Institute convened a two-day public meeting in 2014. This commentary summarizes the most salient issues discussed at the meeting. PMID:27663208

Challenges in evaluating cancer as a clinical outcome in postapproval studies of drug safety.

PubMed

Pinheiro, Simone P; Rivera, Donna R; Graham, David J; Freedman, Andrew N; Major, Jacqueline M; Penberthy, Lynne; Levenson, Mark; Bradley, Marie C; Wong, Hui-Lee; Ouellet-Hellstrom, Rita

2016-11-01

Pharmaceuticals approved in the United States are largely not known human carcinogens. However, cancer signals associated with pharmaceuticals may be hypothesized or arise after product approval. There are many study designs that can be used to evaluate cancer as an outcome in the postapproval setting. Because prospective systematic collection of cancer outcomes from a large number of individuals may be lengthy, expensive, and challenging, leveraging data from large existing databases are an integral approach. Such studies have the capability to evaluate the clinical experience of a large number of individuals, yet there are unique methodological challenges involved in their use to evaluate cancer outcomes. To discuss methodological challenges and potential solutions, the Food and Drug Administration and the National Cancer Institute convened a two-day public meeting in 2014. This commentary summarizes the most salient issues discussed at the meeting. Published by Elsevier Inc.

Mammalian cochlea as a physics guided evolution-optimized hearing sensor.

PubMed

Lorimer, Tom; Gomez, Florian; Stoop, Ruedi

2015-07-28

Nonlinear physics plays an essential role in hearing. We demonstrate on a mesoscopic description level that during the evolutionary perfection of the hearing sensor, nonlinear physics led to the unique design of the cochlea observed in mammals, and that this design requests as a consequence the perception of pitch. Our insight challenges the view that mostly genetics is responsible for the uniformity of the construction of the mammalian hearing sensor. Our analysis also suggests that scaleable and non-scaleable arrangements of nonlinear sound detectors may be at the origin of the differences between hearing sensors in amniotic lineages.

Developing a smartphone app to support the nursing community.

PubMed

Colton, Scott; Hunt, Louise

2016-02-01

Healthcare professionals are turning increasingly to the digital sector to access information they need for their work. Mobile technology, such as smartphones and tablets, provides a unique opportunity to place high-quality information directly into users' hands. This article describes the ongoing development of a smartphone app, Preparing for Caring, designed to prepare the future workforce by enabling mentors and nursing students to access supportive material during practice-based learning episodes. The article explores the rationale for designing the app and discusses the challenges and benefits of developing this resource from the perspectives of student, mentor and healthcare manager.

Modeling Tools Predict Flow in Fluid Dynamics

NASA Technical Reports Server (NTRS)

2010-01-01

"Because rocket engines operate under extreme temperature and pressure, they present a unique challenge to designers who must test and simulate the technology. To this end, CRAFT Tech Inc., of Pipersville, Pennsylvania, won Small Business Innovation Research (SBIR) contracts from Marshall Space Flight Center to develop software to simulate cryogenic fluid flows and related phenomena. CRAFT Tech enhanced its CRUNCH CFD (computational fluid dynamics) software to simulate phenomena in various liquid propulsion components and systems. Today, both government and industry clients in the aerospace, utilities, and petrochemical industries use the software for analyzing existing systems as well as designing new ones."

Achieving appropriate design for developing world heath care: the case of a low-cost autoclave for primary health clinics.

PubMed

Cho, Hallie S; Tao, Gregory D; Winter, Amos

2012-01-01

In developing world health clinics, incidence of surgical site infection is 2 to 10 times higher than in developed world hospitals. This paper identifies lack of availability of appropriately designed, low-cost autoclaves in developing world health clinics as a major contributing factor to the dramatic gap in surgical site infection rates. The paper describes the process of developing a low-cost autoclave that addresses the unique challenges faced by developing world primary health clinics and discusses how appropriateness of design was determined. The resulting pressure cooker-based autoclave design was fabricated and tested against the CDC specifications. Twelve partnering clinics in Nepal trialed these autoclaves from July until December 2012.

A smart rock

NASA Astrophysics Data System (ADS)

Pressel, Phil

2014-12-01

This project was to design and build a protective weapon for a group of associations that believed in aliens and UFO's. They collected enough contributions from societies and individuals to be able to sponsor and totally fund the design, fabrication and testing of this equipment. The location of this facility is classified. It also eventually was redesigned by the Quartus Engineering Company for use at a major amusement park as a "shoot at targets facility." The challenge of this project was to design a "smart rock," namely an infrared bullet (the size of a gallon can of paint) that could be shot from the ground to intercept a UFO or any incoming suspicious item heading towards the earth. Some of the challenges to design this weapon were to feed cryogenic helium at 5 degrees Kelvin from an inair environment through a unique rotary coupling and air-vacuum seal while spinning the bullet at 1500 rpm and maintain its dynamic stability (wobble) about its spin axis to less than 10 micro-radians (2 arc seconds) while it operated in a vacuum. Precision optics monitored the dynamic motion of the "smart rock."

Unmanned Aerial Vehicles unique cost estimating requirements

NASA Astrophysics Data System (ADS)

Malone, P.; Apgar, H.; Stukes, S.; Sterk, S.

Unmanned Aerial Vehicles (UAVs), also referred to as drones, are aerial platforms that fly without a human pilot onboard. UAVs are controlled autonomously by a computer in the vehicle or under the remote control of a pilot stationed at a fixed ground location. There are a wide variety of drone shapes, sizes, configurations, complexities, and characteristics. Use of these devices by the Department of Defense (DoD), NASA, civil and commercial organizations continues to grow. UAVs are commonly used for intelligence, surveillance, reconnaissance (ISR). They are also use for combat operations, and civil applications, such as firefighting, non-military security work, surveillance of infrastructure (e.g. pipelines, power lines and country borders). UAVs are often preferred for missions that require sustained persistence (over 4 hours in duration), or are “ too dangerous, dull or dirty” for manned aircraft. Moreover, they can offer significant acquisition and operations cost savings over traditional manned aircraft. Because of these unique characteristics and missions, UAV estimates require some unique estimating methods. This paper describes a framework for estimating UAV systems total ownership cost including hardware components, software design, and operations. The challenge of collecting data, testing the sensitivities of cost drivers, and creating cost estimating relationships (CERs) for each key work breakdown structure (WBS) element is discussed. The autonomous operation of UAVs is especially challenging from a software perspective.

Solid Rocket Booster (SRB) Flight System Integration at Its Best

NASA Technical Reports Server (NTRS)

Wood, T. David; Kanner, Howard S.; Freeland, Donna M.; Olson, Derek T.

2011-01-01

The Solid Rocket Booster (SRB) element integrates all the subsystems needed for ascent flight, entry, and recovery of the combined Booster and Motor system. These include the structures, avionics, thrust vector control, pyrotechnic, range safety, deceleration, thermal protection, and retrieval systems. This represents the only human-rated, recoverable and refurbishable solid rocket ever developed and flown. Challenges included subsystem integration, thermal environments and severe loads (including water impact), sometimes resulting in hardware attrition. Several of the subsystems evolved during the program through design changes. These included the thermal protection system, range safety system, parachute/recovery system, and others. Because the system was recovered, the SRB was ideal for data and imagery acquisition, which proved essential for understanding loads, environments and system response. The three main parachutes that lower the SRBs to the ocean are the largest parachutes ever designed, and the SRBs are the largest structures ever to be lowered by parachutes. SRB recovery from the ocean was a unique process and represented a significant operational challenge; requiring personnel, facilities, transportation, and ground support equipment. The SRB element achieved reliability via extensive system testing and checkout, redundancy management, and a thorough postflight assessment process. However, the in-flight data and postflight assessment process revealed the hardware was affected much more strongly than originally anticipated. Assembly and integration of the booster subsystems required acceptance testing of reused hardware components for each build. Extensive testing was done to assure hardware functionality at each level of stage integration. Because the booster element is recoverable, subsystems were available for inspection and testing postflight, unique to the Shuttle launch vehicle. Problems were noted and corrective actions were implemented as needed. The postflight assessment process was quite detailed and a significant portion of flight operations. The SRBs provided fully redundant critical systems including thrust vector control, mission critical pyrotechnics, avionics, and parachute recovery system. The design intent was to lift off with full redundancy. On occasion, the redundancy management scheme was needed during flight operations. This paper describes some of the design challenges and technical issues, how the design evolved with time, and key areas where hardware reusability contributed to improved system level understanding.

The REFLECT statement: methods and processes of creating reporting guidelines for randomized controlled trials for livestock and food safety.

PubMed

O'Connor, A M; Sargeant, J M; Gardner, I A; Dickson, J S; Torrence, M E; Dewey, C E; Dohoo, I R; Evans, R B; Gray, J T; Greiner, M; Keefe, G; Lefebvre, S L; Morley, P S; Ramirez, A; Sischo, W; Smith, D R; Snedeker, K; Sofos, J; Ward, M P; Wills, R

2010-01-01

The conduct of randomized controlled trials in livestock with production, health, and food-safety outcomes presents unique challenges that might not be adequately reported in trial reports. The objective of this project was to modify the CONSORT (Consolidated Standards of Reporting Trials) statement to reflect the unique aspects of reporting these livestock trials. A 2-day consensus meeting was held on November 18-19, 2008 in Chicago, IL, to achieve the objective. Before the meeting, a Web-based survey was conducted to identify issues for discussion. The 24 attendees were biostatisticians, epidemiologists, food-safety researchers, livestock production specialists, journal editors, assistant editors, and associate editors. Before the meeting, the attendees completed a Web-based survey indicating which CONSORT statement items would need to be modified to address unique issues for livestock trials. The consensus meeting resulted in the production of the REFLECT (Reporting Guidelines for Randomized Control Trials) statement for livestock and food safety and 22-item checklist. Fourteen items were modified from the CONSORT checklist, and an additional subitem was proposed to address challenge trials. The REFLECT statement proposes new terminology, more consistent with common usage in livestock production, to describe study subjects. Evidence was not always available to support modification to or inclusion of an item. The use of the REFLECT statement, which addresses issues unique to livestock trials, should improve the quality of reporting and design for trials reporting production, health, and food-safety outcomes.

Integration of Multifidelity Multidisciplinary Computer Codes for Design and Analysis of Supersonic Aircraft

NASA Technical Reports Server (NTRS)

Geiselhart, Karl A.; Ozoroski, Lori P.; Fenbert, James W.; Shields, Elwood W.; Li, Wu

2011-01-01

This paper documents the development of a conceptual level integrated process for design and analysis of efficient and environmentally acceptable supersonic aircraft. To overcome the technical challenges to achieve this goal, a conceptual design capability which provides users with the ability to examine the integrated solution between all disciplines and facilitates the application of multidiscipline design, analysis, and optimization on a scale greater than previously achieved, is needed. The described capability is both an interactive design environment as well as a high powered optimization system with a unique blend of low, mixed and high-fidelity engineering tools combined together in the software integration framework, ModelCenter. The various modules are described and capabilities of the system are demonstrated. The current limitations and proposed future enhancements are also discussed.

The Need for an Aerospace Pharmacy Residency

NASA Technical Reports Server (NTRS)

Bayuse, T.; Schuyler, C.; Bayuse, Tina M.

2007-01-01

This viewgraph poster presentation reviews the rationale for a call for a new program in residency for aerospace pharmacy. Aerospace medicine provides a unique twist on traditional medicine, and a specialty has evolved to meet the training for physicians, and it is becoming important to develop such a program for training in pharmacy designed for aerospace. The reasons for this specialist training are outlined and the challenges of developing a program are reviewed.

The Battle of Jutland

DTIC Science & Technology

1984-04-01

battle- cruiser LJLQQ,, was "booed" and "jeered at" by dockyard workmen as she slipped into her berth after the battle ( 12 :250). Why such a negative...of May in 1916. Until the Battle of Jutland, the Royal Navy had not been seriously challenged since 1805 when Admirals Nelson and...Unique because of its design as an "all big-gun ship," she carried ten 12 -inch guns, was turbine driven, and

Applying a Systems Approach to School-Wide Discipline in Secondary Schools: What We Are Learning and Need To Learn. CASE/CCBD Mini-Library Series on Safe, Drug-Free, and Effective Schools.

ERIC Educational Resources Information Center

Lewis-Palmer, Teri; Flannery, Brigid; Sugai, George; Eber, Lucille

This monograph describes the unique features of secondary schools and the application of a systems approach to school discipline at the secondary level. The use of effective behavior support (EBS) designed to increase the capacity of schools to educate all students, especially students with behavioral challenges, is highlighted. Critical features…

Requirements for Space Settlement Design

NASA Astrophysics Data System (ADS)

Gale, Anita E.; Edwards, Richard P.

2004-02-01

When large space settlements are finally built, inevitably the customers who pay for them will start the process by specifying requirements with a Request for Proposal (RFP). Although we are decades away from seeing the first of these documents, some of their contents can be anticipated now, and provide insight into the variety of elements that must be researched and developed before space settlements can happen. Space Settlement Design Competitions for High School students present design challenges in the form of RFPs, which predict basic requirements for space settlement attributes in the future, including structural features, infrastructure, living conveniences, computers, business areas, and safety. These requirements are generically summarized, and unique requirements are noted for specific space settlement locations and applications.

Field Guide for Designing Human Interaction with Intelligent Systems

NASA Technical Reports Server (NTRS)

Malin, Jane T.; Thronesbery, Carroll G.

1998-01-01

The characteristics of this Field Guide approach address the problems of designing innovative software to support user tasks. The requirements for novel software are difficult to specify a priori, because there is not sufficient understanding of how the users' tasks should be supported, and there are not obvious pre-existing design solutions. When the design team is in unfamiliar territory, care must be taken to avoid rushing into detailed design, requirements specification, or implementation of the wrong product. The challenge is to get the right design and requirements in an efficient, cost-effective manner. This document's purpose is to describe the methods we are using to design human interactions with intelligent systems which support Space Shuttle flight controllers in the Mission Control Center at NASA/Johnson Space Center. Although these software systems usually have some intelligent features, the design challenges arise primarily from the innovation needed in the software design. While these methods are tailored to our specific context, they should be extensible, and helpful to designers of human interaction with other types of automated systems. We review the unique features of this context so that you can determine how to apply these methods to your project Throughout this Field Guide, goals of the design methods are discussed. This should help designers understand how a specific method might need to be adapted to the project at hand.

Making Full Use of the Longitudinal Design of the Current Population Survey: Methods for Linking Records Across 16 Months *

PubMed Central

Drew, Julia A. Rivera; Flood, Sarah; Warren, John Robert

2015-01-01

Data from the Current Population Survey (CPS) are rarely analyzed in a way that takes advantage of the CPS’s longitudinal design. This is mainly because of the technical difficulties associated with linking CPS files across months. In this paper, we describe the method we are using to create unique identifiers for all CPS person and household records from 1989 onward. These identifiers—available along with CPS basic and supplemental data as part of the on-line Integrated Public Use Microdata Series (IPUMS)—make it dramatically easier to use CPS data for longitudinal research across any number of substantive domains. To facilitate the use of these new longitudinal IPUMS-CPS data, we also outline seven different ways that researchers may choose to link CPS person records across months, and we describe the sample sizes and sample retention rates associated with these seven designs. Finally, we discuss a number of unique methodological challenges that researchers will confront when analyzing data from linked CPS files. PMID:26113770

Design of Phase I Combination Trials: Recommendations of the Clinical Trial Design Task Force of the NCI Investigational Drug Steering Committee

PubMed Central

Paller, Channing J.; Bradbury, Penelope A.; Ivy, S. Percy; Seymour, Lesley; LoRusso, Patricia M.; Baker, Laurence; Rubinstein, Larry; Huang, Erich; Collyar, Deborah; Groshen, Susan; Reeves, Steven; Ellis, Lee M.; Sargent, Daniel J.; Rosner, Gary L.; LeBlanc, Michael L.; Ratain, Mark J.

2014-01-01

Anticancer drugs are combined in an effort to treat a heterogeneous tumor or to maximize the pharmacodynamic effect. The development of combination regimens, while desirable, poses unique challenges. These include the selection of agents for combination therapy that may lead to improved efficacy while maintaining acceptable toxicity, the design of clinical trials that provide informative results for individual agents and combinations, and logistical and regulatory challenges. The phase 1 trial is often the initial step in the clinical evaluation of a combination regimen. In view of the importance of combination regimens and the challenges associated with developing them, the Clinical Trial Design (CTD) Task Force of the National Cancer Institute (NCI) Investigational Drug Steering Committee developed a set of recommendations for the phase 1 development of a combination regimen. The first two recommendations focus on the scientific rationale and development plans for the combination regimen; subsequent recommendations encompass clinical design aspects. The CTD Task Force recommends that selection of the proposed regimens be based on a biological or pharmacological rationale supported by clinical and/or robust and validated preclinical evidence, and accompanied by a plan for subsequent development of the combination. The design of the phase 1 clinical trial should take into consideration the potential pharmacokinetic and pharmacodynamic interactions as well as overlapping toxicity. Depending on the specific hypothesized interaction, the primary endpoint may be dose optimization, pharmacokinetics, and/or pharmacodynamic (i.e., biomarker). PMID:25125258

The new frontier of public health education.

PubMed

Birnbaum, David; Gretsinger, Kathryn; Ellis, Ursula

2017-02-06

Purpose The aim of this paper is to describe the experience and educational benefits of a course that has several unique educational design features. Design/methodology/approach This includes narrative description of faculty and student experience from participants in a flipped-instructional-design inter-professional education course. Findings "Improving Public Health - An Interprofessional Approach to Designing and Implementing Effective Interventions" is an undergraduate public health course open to students regardless of background. Its student activities mirror the real-life tasks and challenges of working in a public health agency, including team-building and leadership; problem and project definition and prioritization; evidence-finding and critical appraisal; written and oral presentation; and press interviews. Students successfully developed project proposals to address real problems in a wide range of communities and settings and refined those proposals through interaction with professionals from population and public health, journalism and library sciences. Practical implications Undergraduate public health education is a relatively new endeavor, and experience with this new approach may be of value to other educators. Originality/value Students in this course, journalism graduate students who conducted mock interviews with them and instructors who oversaw the course all describe unique aspects and related personal benefit from this novel approach.

Terra Mission Operations: Launch to the Present (and Beyond)

NASA Technical Reports Server (NTRS)

Kelly, Angelita; Moyer, Eric; Mantziaras, Dimitrios; Case, Warren

2014-01-01

The Terra satellite, flagship of NASA's long-term Earth Observing System (EOS) Program, continues to provide useful earth science observations well past its 5-year design lifetime. This paper describes the evolution of Terra operations, including challenges and successes and the steps taken to preserve science requirements and prolong spacecraft life. Working cooperatively with the Terra science and instrument teams, including NASA's international partners, the mission operations team has successfully kept the Terra operating continuously, resolving challenges and adjusting operations as needed. Terra retains all of its observing capabilities (except Short Wave Infrared) despite its age. The paper also describes concepts for future operations. This paper will review the Terra spacecraft mission successes and unique spacecraft component designs that provided significant benefits extending mission life and science. In addition, it discusses special activities as well as anomalies and corresponding recovery efforts. Lastly, it discusses future plans for continued operations.

Lunar base habitat designs: Characterizing the environment, and selecting habitat designs for future trade-offs

NASA Technical Reports Server (NTRS)

Ganapathi, Gani B.; Ferrall, Joseph; Seshan, P. K.

1993-01-01

A survey of distinct conceptual lunar habitat designs covering the pre- and post-Apollo era is presented. The impact of the significant lunar environmental challenges such as temperature, atmosphere, radiation, soil properties, meteorites, and seismic activity on the habitat design parameters are outlined. Over twenty habitat designs were identified and classified according to mission type, crew size; total duration of stay, modularity, environmental protection measures, and emplacement. Simple selection criteria of (1) post-Apollo design, (2) uniqueness of the habitat design, (3) level of thoroughness in design layout, (4) habitat dimensions are provided, and (5) materials of construction for the habitat shell are specified, are used to select five habitats for future trade studies. Habitat emplacement scenarios are created to examine the possible impact of emplacement of the habitat in different locations, such as lunar poles vs. equatorial, above ground vs. below ground, etc.

Evaluation of occupational health interventions using a randomized controlled trial: challenges and alternative research designs.

PubMed

Schelvis, Roosmarijn M C; Oude Hengel, Karen M; Burdorf, Alex; Blatter, Birgitte M; Strijk, Jorien E; van der Beek, Allard J

2015-09-01

Occupational health researchers regularly conduct evaluative intervention research for which a randomized controlled trial (RCT) may not be the most appropriate design (eg, effects of policy measures, organizational interventions on work schedules). This article demonstrates the appropriateness of alternative designs for the evaluation of occupational health interventions, which permit causal inferences, formulated along two study design approaches: experimental (stepped-wedge) and observational (propensity scores, instrumental variables, multiple baseline design, interrupted time series, difference-in-difference, and regression discontinuity). For each design, the unique characteristics are presented including the advantages and disadvantages compared to the RCT, illustrated by empirical examples in occupational health. This overview shows that several appropriate alternatives for the RCT design are feasible and available, which may provide sufficiently strong evidence to guide decisions on implementation of interventions in workplaces. Researchers are encouraged to continue exploring these designs and thus contribute to evidence-based occupational health.

Design and control of compliant tensegrity robots through simulation and hardware validation

PubMed Central

Caluwaerts, Ken; Despraz, Jérémie; Işçen, Atıl; Sabelhaus, Andrew P.; Bruce, Jonathan; Schrauwen, Benjamin; SunSpiral, Vytas

2014-01-01

To better understand the role of tensegrity structures in biological systems and their application to robotics, the Dynamic Tensegrity Robotics Lab at NASA Ames Research Center, Moffett Field, CA, USA, has developed and validated two software environments for the analysis, simulation and design of tensegrity robots. These tools, along with new control methodologies and the modular hardware components developed to validate them, are presented as a system for the design of actuated tensegrity structures. As evidenced from their appearance in many biological systems, tensegrity (‘tensile–integrity’) structures have unique physical properties that make them ideal for interaction with uncertain environments. Yet, these characteristics make design and control of bioinspired tensegrity robots extremely challenging. This work presents the progress our tools have made in tackling the design and control challenges of spherical tensegrity structures. We focus on this shape since it lends itself to rolling locomotion. The results of our analyses include multiple novel control approaches for mobility and terrain interaction of spherical tensegrity structures that have been tested in simulation. A hardware prototype of a spherical six-bar tensegrity, the Reservoir Compliant Tensegrity Robot, is used to empirically validate the accuracy of simulation. PMID:24990292

KineAssist: design and development of a robotic overground gait and balance therapy device.

PubMed

Patton, James; Brown, David A; Peshkin, Michael; Santos-Munné, Julio J; Makhlin, Alex; Lewis, Ela; Colgate, Edward J; Schwandt, Doug

2008-01-01

Balance and mobility training consists of activities that carry a high risk for falling. The purpose of this article is to describe a novel robotic system for allowing challenging, yet safe, balance and mobility training in persons at high risk for falls. With no initial preconceptions of what device we would build, a user-needs analysis led us to focus on increasing the level of challenge to a patient's ability to maintain balance during gait training and also on maintaining direct involvement of a physical therapist (rather than attempting robotic replacement). The KineAssist is a robotic device for gait and balance training that has emerged from a unique design process of a start-up product of a small company and a team of therapists, engineers, mechanical design experts, and rehabilitation scientists. The KineAssist provides partial body weight support and postural control on the torso; allows many axes of motion of the trunk and pelvis; leaves the patient's legs accessible to a physical therapist's manipulation during walking; follows a patient's walking motions overground in forward, rotation, and sidestepping directions; and catches an individual who loses balance and begins to fall. Design and development of the KineAssist proceeded more rapidly in the context of a small company than would have been possible in most institutional research contexts. A prototype KineAssist has been constructed and has received US Food and Drug Administration (FDA) classification and institutional review board clearance for initial human studies. The acceptance of KineAssist will ultimately depend on improved patient outcomes, the use of this new tool by therapists, the ease of use of the system, and the recognition of the unique value it brings to therapeutic recovery.

A Design Comparison of Atmospheric Flight Vehicles for the Exploration of Titan

NASA Technical Reports Server (NTRS)

Gasbarre, Joseph F.; Wright, Henry S.; Lewis, Mark J.

2005-01-01

Titan, the largest moon of Saturn, is one of the most scientifically interesting locations in the Solar System. With a very cold atmosphere that is five times as dense as Earth s, and one and a half times the surface pressure, it also provides one of the most aeronautically fascinating environments known to humankind. While this may seem the ideal place to attempt atmospheric flight, many challenges await any vehicle attempting to navigate through it. In addition to these physical challenges, any scientific exploration mission to Titan will most likely have several operational constraints. One difficult constraint is the desire for a global survey of the planet and thus, a long duration flight within the atmosphere. Since many of the scientific measurements that would be unique to a vehicle flying through the atmosphere (as opposed to an orbiting spacecraft) desire near-surface positioning of their associated instruments, the vehicle must also be able to fly within the first scale height of the atmosphere. Another difficult constraint is that interaction with the surface, whether by landing or dropped probe, is also highly desirable from a scientific perspective. Two common atmospheric flight platforms that might be used for this mission are the airplane and airship. Under the assumption of a mission architecture that would involve an orbiting relay spacecraft delivered via aerocapture and an atmospheric flight vehicle delivered via direct entry, designs were developed for both platforms that are unique to Titan. Consequently, after a viable design was achieved for each platform, their advantages and disadvantages were compared. This comparison included such factors as deployment risk, surface interaction capability, mass, and design heritage. When considering all factors, the preferred candidate platform for a global survey of Titan is an airship.

Challenges to clinical deployment of upper limb neuroprostheses.

PubMed

Triolo, R; Nathan, R; Handa, Y; Keith, M; Betz, R R; Carroll, S; Kantor, C

1996-04-01

The technology for functional neuromuscular stimulation (FNS) as a means of providing upper limb function to people with tetraplegia has been under development by three clinical research groups for almost two decades. This paper presents the current status of the clinical trials of three FNS systems: a noninvasive system built into a cosmetic forearm splint, a 30-channel percutaneous system, and an 8-channel implantable system. The complexity of FNS systems and the unique characteristics of the individuals to whom they are applied combine to create many clinical and technical challenges that must be addressed before the devices can be deployed. The emerging challenges to widespread clinical introduction of FNS systems for hand and arm function are identified and analyzed. In addition to the demands of designed and conducting the clinical trials to satisfy regulatory requirements, the lack of knowledge, skepticism, and the complacency on the part of potential FNS recipients, as well as of rehabilitation professionals, must be overcome through education and careful consideration of economic and societal factors in the design of clinical systems.

NASA Space Flight Vehicle Fault Isolation Challenges

NASA Technical Reports Server (NTRS)

Bramon, Christopher; Inman, Sharon K.; Neeley, James R.; Jones, James V.; Tuttle, Loraine

2016-01-01

The Space Launch System (SLS) is the new NASA heavy lift launch vehicle and is scheduled for its first mission in 2017. The goal of the first mission, which will be uncrewed, is to demonstrate the integrated system performance of the SLS rocket and spacecraft before a crewed flight in 2021. SLS has many of the same logistics challenges as any other large scale program. Common logistics concerns for SLS include integration of discrete programs geographically separated, multiple prime contractors with distinct and different goals, schedule pressures and funding constraints. However, SLS also faces unique challenges. The new program is a confluence of new hardware and heritage, with heritage hardware constituting seventy-five percent of the program. This unique approach to design makes logistics concerns such as testability of the integrated flight vehicle especially problematic. The cost of fully automated diagnostics can be completely justified for a large fleet, but not so for a single flight vehicle. Fault detection is mandatory to assure the vehicle is capable of a safe launch, but fault isolation is another issue. SLS has considered various methods for fault isolation which can provide a reasonable balance between adequacy, timeliness and cost. This paper will address the analyses and decisions the NASA Logistics engineers are making to mitigate risk while providing a reasonable testability solution for fault isolation.

Heterogeneous electrochemical CO2 reduction using nonmetallic carbon-based catalysts: current status and future challenges

NASA Astrophysics Data System (ADS)

Ma, Tao; Fan, Qun; Tao, Hengcong; Han, Zishan; Jia, Mingwen; Gao, Yunnan; Ma, Wangjing; Sun, Zhenyu

2017-11-01

Electrochemical CO2 reduction (ECR) offers an important pathway for renewable energy storage and fuels production. It still remains a challenge in designing highly selective, energy-efficient, robust, and cost-effective electrocatalysts to facilitate this kinetically slow process. Metal-free carbon-based materials have features of low cost, good electrical conductivity, renewability, diverse structure, and tunability in surface chemistry. In particular, surface functionalization of carbon materials, for example by doping with heteroatoms, enables access to unique active site architectures for CO2 adsorption and activation, leading to interesting catalytic performances in ECR. We aim to provide a comprehensive review of this category of metal-free catalysts for ECR, providing discussions and/or comparisons among different nonmetallic catalysts, and also possible origin of catalytic activity. Fundamentals and some future challenges are also described.

Technology Transfer Challenges: A Case Study of User-Centered Design in NASA's Systems Engineering Culture

NASA Technical Reports Server (NTRS)

Quick, Jason

2009-01-01

The Upper Stage (US) section of the National Aeronautics and Space Administration's (NASA) Ares I rocket will require internal access platforms for maintenance tasks performed by humans inside the vehicle. Tasks will occur during expensive critical path operations at Kennedy Space Center (KSC) including vehicle stacking and launch preparation activities. Platforms must be translated through a small human access hatch, installed in an enclosed worksite environment, support the weight of ground operators and be removed before flight - and their design must minimize additional vehicle mass at attachment points. This paper describes the application of a user-centered conceptual design process and the unique challenges encountered within NASA's systems engineering culture focused on requirements and "heritage hardware". The NASA design team at Marshall Space Flight Center (MSFC) initiated the user-centered design process by studying heritage internal access kits and proposing new design concepts during brainstorming sessions. Simultaneously, they partnered with the Technology Transfer/Innovative Partnerships Program to research inflatable structures and dynamic scaffolding solutions that could enable ground operator access. While this creative, technology-oriented exploration was encouraged by upper management, some design stakeholders consistently opposed ideas utilizing novel, untested equipment. Subsequent collaboration with an engineering consulting firm improved the technical credibility of several options, however, there was continued resistance from team members focused on meeting system requirements with pre-certified hardware. After a six-month idea-generating phase, an intensive six-week effort produced viable design concepts that justified additional vehicle mass while optimizing the human factors of platform installation and use. Although these selected final concepts closely resemble heritage internal access platforms, challenges from the application of the user-centered process provided valuable lessons for improving future collaborative conceptual design efforts.

KSC-2012-3092

NASA Image and Video Library

2012-05-26

CAPE CANAVERAL, Fla. – Teams taking part in NASA's Lunabotics Mining Competition were eligible for unique trophies such as this. The competition challenged university students to build machines that could collect soil such as the material found on the moon. Working inside the Caterpillar LunArena, the robotic craft dug soil that simulated lunar material. The event was judged by a machine's abilities to collect the soil, its design and operation, size, dust tolerance and its level of autonomy. Photo credit: NASA/Jim Grossmann

Shrinking the Supply Chain for Implantable Coronary Stent Devices.

PubMed

Moore, Sean S; O'Sullivan, Kevin J; Verdecchia, Francesco

2016-02-01

Stenting treatments for the management of disease in the heart, arterial and venous systems, biliary ducts, urethras, ureters, oesophageal tract and prostate have made enormous technical advances since their introduction into clinical use. The progression from metallic to polymer based bio-absorbable stents, coupled with the advances in additive manufacturing techniques, present a unique opportunity to completely re-envision the design, manufacture, and supply chain of stents. This paper looks at current stenting trends and proposes a future where the stent supply chain is condensed from ~150 days to ~20 min. The Cardiologist therefore has the opportunity to become a designer, manufacturer and user with patients receiving custom stents specific to their unique pathology that will be generated, delivered and deployed in the Cath-lab. The paper will outline this potentially revolutionary development and consider the technical challenges that will need to be overcome in order to achieve these ambitious goals. A high level overview of the generating eluting stents in situ program-GENESIS-is outlined including some early experimental work.

Adolescents and young adults with acute lymphoblastic leukemia.

PubMed

Stock, Wendy

2010-01-01

During the last decade, increasing attention has been paid to a unique group of patients with acute lymphoblastic leukemia (ALL) who lie at the crossroad of therapeutic care by pediatric and adult hematologists/oncologists. ALL is a disease that affects infants, children, adolescents, and adult patients. With current therapies, the vast majority of children with ALL are now long-term survivors; unfortunately, the same good results have not yet been obtained for adults with ALL. This review will describe current controversies surrounding the treatment of adolescents and young adults with ALL--a group who finds themselves in the transition from "pediatric" to "adult" treatment approaches. The review focuses on recent insights into disease biology, prognostic factors, and treatment outcomes that have led to a series of prospective clinical trials specifically designed for adolescents and younger adults (AYAs) with ALL. These trials have been designed to provide important new clinical, psychosocial, and biological insights, and to further improve the survival of this challenging and unique group of patients.

Developing Smartphone Apps for Education, Outreach, Science, and Engineering

NASA Astrophysics Data System (ADS)

Weatherwax, A. T.; Fitzsimmons, Z.; Czajkowski, J.; Breimer, E.; Hellman, S. B.; Hunter, S.; Dematteo, J.; Savery, T.; Melsert, K.; Sneeringer, J.

2010-12-01

The increased popularity of mobile phone apps provide scientists with a new avenue for sharing and distributing data and knowledge with colleagues, while also providing meaningful education and outreach products for consumption by the general public. Our initial development of iPhone and Android apps centered on the distribution of exciting auroral images taken at the South Pole for education and outreach purposes. These portable platforms, with limited resources when compared to computers, presented a unique set of design and implementation challenges that we will discuss in this presentation. For example, the design must account for limited memory; screen size; processing power; battery life; and potentially high data transport costs. Some of these unique requirements created an environment that enabled undergraduate and high-school students to participate in the creation of these apps. Additionally, during development it became apparent that these apps could also serve as data analysis and engineering tools. Our presentation will further discuss our plans to use apps not only for Education and Public Outreach, but for teaching, science and engineering.

Metrology for the manufacturing of freeform optics

NASA Astrophysics Data System (ADS)

Blalock, Todd; Myer, Brian; Ferralli, Ian; Brunelle, Matt; Lynch, Tim

2017-10-01

Recently the use of freeform surfaces have become a realization for optical designers. These non-symmetrical optical surfaces have allowed unique solutions to optical design problems. The implementation of freeform optical surfaces has been limited by manufacturing capabilities and quality. However over the past several years freeform fabrication processes have improved in capability and precision. But as with any manufacturing, proper metrology is required to monitor and verify the process. Typical optics metrology such as interferometry has its challenges and limitations with the unique shapes of freeform optics. Two contact metrology methods for freeform metrology are presented; a Leitz coordinate measurement machine (CMM) with an uncertainty of +/- 0.5 μm and a high resolution profilometer (Panasonic UA3P) with a measurement uncertainty of +/- 0.05 μm. We are also developing a non-contact high resolution technique based on the fringe reflection technique known as deflectometry. This fast non-contact metrology has the potential to compete with accuracies of the contact methods but also can acquire data in seconds rather than minutes or hours.

Development and preliminary testing of a web-based, self-help application for disaster-affected families.

PubMed

Yuen, Erica K; Gros, Kirstin; Welsh, Kyleen E; McCauley, Jenna; Resnick, Heidi S; Danielson, Carla K; Price, Matthew; Ruggiero, Kenneth J

2016-09-01

Technology-based self-help interventions have the potential to increase access to evidence-based mental healthcare, especially for families affected by natural disasters. However, development of these interventions is a complex process and poses unique challenges. Usability testing, which assesses the ability of individuals to use an application successfully, can have a significant impact on the quality of a self-help intervention. This article describes (a) the development of a novel web-based multi-module self-help intervention for disaster-affected adolescents and their parents and (b) a mixed-methods formal usability study to evaluate user response. A total of 24 adolescents were observed, videotaped, and interviewed as they used the depressed mood component of the self-help intervention. Quantitative results indicated an above-average user experience, and qualitative analysis identified 120 unique usability issues. We discuss the challenges of developing self-help applications, including design considerations and the value of usability testing in technology-based interventions, as well as our plan for widespread dissemination. © The Author(s) 2015.

Ground test challenges in the development of the Space Shuttle orbiter auxiliary power unit

NASA Technical Reports Server (NTRS)

Chaffee, N. H.; Lance, R. J.; Weary, D. P.

1984-01-01

A conventional aircraft hydraulic system design approach was selected to provide fluid power for the Space Shuttle Orbiter. Developing the power unit, known as the Auxiliary Power Unit (APU), to drive the hydraulic pumps presented a major technological challenge. A small, high speed turbine drive unit powered by catalytically decomposed hydrazine and operating in the pulse mode was selected to meet the requirement. Because of limitations of vendor test facilities, significant portions of the development, flight qualification, and postflight anomaly testing of the Orbiter APU were accomplished at the Johnson Space Center (JSC) test facilities. This paper discusses the unique requirements of attitude, gravity forces, pressure profiles, and thermal environments which had to be satisfied by the APU, and presents the unique test facility and simulation techniques employed to meet the ground test requirements. In particular, the development of the zero-g lubrication system, the development of necessary APU thermal control techniques, the accomplishment of integrated systems tests, and the postflight investigation of the APU lube oil cooler behavior are discussed.

CRBRP modular steam generator tube-to-tubesheet and shell-closure welding

DOE Office of Scientific and Technical Information (OSTI.GOV)

Viri, D.P.

1982-01-01

The original Modular Steam Generator (MSG), whiand inh was designed, built, and tested by the Energy Systems Group (ESG) of Rockwell International, was a departure from conventional boilers or heat exchangers. The design was a hockeystick concept - the upper section of the generator is curved 90/sup 0/. Factors affecting operating parameters were considered and incorporated in the original MSG design. The MSG was fully instrumented and functionally tested at the Energy Technology Engineering Center at Rockwell. The MSG steamed continuously for over 4000 h, and at the conclusion of the 9000-h test cycle, it was systematically dismantled and examinedmore » for wear to critical components. This paper explains the solutions to several manufacturing challenges presented by the unique design of the MSG.« less

A Survey of Cost Estimating Methodologies for Distributed Spacecraft Missions

NASA Technical Reports Server (NTRS)

Foreman, Veronica L.; Le Moigne, Jacqueline; de Weck, Oliver L.

2016-01-01

Satellite constellations and Distributed Spacecraft Mission (DSM) architectures offer unique benefits to Earth observation scientists and unique challenges to cost estimators. The Cost and Risk (CR) module of the Tradespace Analysis Tool for Constellations (TAT-C) being developed by NASA Goddard seeks to address some of these challenges by providing a new approach to cost modeling, which aggregates existing Cost Estimating Relationships (CER) from respected sources, cost estimating best practices, and data from existing and proposed satellite designs. Cost estimation through this tool is approached from two perspectives: parametric cost estimating relationships and analogous cost estimation techniques. The dual approach utilized within the TAT-C CR module is intended to address prevailing concerns regarding early design stage cost estimates, and offer increased transparency and fidelity by offering two preliminary perspectives on mission cost. This work outlines the existing cost model, details assumptions built into the model, and explains what measures have been taken to address the particular challenges of constellation cost estimating. The risk estimation portion of the TAT-C CR module is still in development and will be presented in future work. The cost estimate produced by the CR module is not intended to be an exact mission valuation, but rather a comparative tool to assist in the exploration of the constellation design tradespace. Previous work has noted that estimating the cost of satellite constellations is difficult given that no comprehensive model for constellation cost estimation has yet been developed, and as such, quantitative assessment of multiple spacecraft missions has many remaining areas of uncertainty. By incorporating well-established CERs with preliminary approaches to approaching these uncertainties, the CR module offers more complete approach to constellation costing than has previously been available to mission architects or Earth scientists seeking to leverage the capabilities of multiple spacecraft working in support of a common goal.

Design control considerations for biologic-device combination products.

PubMed

Anderson, Dave; Liu, Roger; Anand Subramony, J; Cammack, Jon

2017-03-01

Combination products are therapeutic and diagnostic medical products that combine drugs, devices, and/or biological products with one another. Historically, biologics development involved identifying efficacious doses administered to patients intravenously or perhaps by a syringe. Until fairly recently, there has been limited focus on developing an accompanying medical device, such as a prefilled syringe or auto-injector, to enable easy and more efficient delivery. For the last several years, and looking forward, where there may be little to distinguish biologics medicines with relatively similar efficacy profiles, the biotechnology market is beginning to differentiate products by patient-focused, biologic-device based combination products. As innovative as biologic-device combination products are, they can pose considerable development, regulatory, and commercialization challenges due to unique physicochemical properties and special clinical considerations (e.g., dosing volumes, frequency, co-medications, etc.) of the biologic medicine. A biologic-device combination product is a marriage between two partners with "cultural differences," so to speak. There are clear differences in the development, review, and commercialization processes of the biologic and the device. When these two cultures come together in a combination product, developers and reviewers must find ways to address the design controls and risk management processes of both the biologic and device, and knit them into a single entity with supporting product approval documentation. Moreover, digital medicine and connected health trends are pushing the boundaries of combination product development and regulations even further. Despite an admirable cooperation between industry and FDA in recent years, unique product configurations and design features have resulted in review challenges. These challenges have prompted agency reviewers to modernize consultation processes, while at the same time, promoting development of innovative, safe and effective combination products. It remains the manufacturer's responsibility to comply with the relevant requirements and regulations, and develop good business practices that clearly describe how these practices comply with FDA's final rule (21 CFR Part 4) and aligns with the company's already established quality system. Copyright © 2017 Elsevier B.V. All rights reserved.

Development of the Multiple Use Plug Hybrid for Nanosats (MUPHyN) miniature thruster

NASA Astrophysics Data System (ADS)

Eilers, Shannon

The Multiple Use Plug Hybrid for Nanosats (MUPHyN) prototype thruster incorporates solutions to several major challenges that have traditionally limited the deployment of chemical propulsion systems on small spacecraft. The MUPHyN thruster offers several features that are uniquely suited for small satellite applications. These features include 1) a non-explosive ignition system, 2) non-mechanical thrust vectoring using secondary fluid injection on an aerospike nozzle cooled with the oxidizer flow, 3) a non-toxic, chemically-stable combination of liquid and inert solid propellants, 4) a compact form factor enabled by the direct digital manufacture of the inert solid fuel grain. Hybrid rocket motors provide significant safety and reliability advantages over both solid composite and liquid propulsion systems; however, hybrid motors have found only limited use on operational vehicles due to 1) difficulty in modeling the fuel flow rate 2) poor volumetric efficiency and/or form factor 3) significantly lower fuel flow rates than solid rocket motors 4) difficulty in obtaining high combustion efficiencies. The features of the MUPHyN thruster are designed to offset and/or overcome these shortcomings. The MUPHyN motor design represents a convergence of technologies, including hybrid rocket regression rate modeling, aerospike secondary injection thrust vectoring, multiphase injector modeling, non-pyrotechnic ignition, and nitrous oxide regenerative cooling that address the traditional challenges that limit the use of hybrid rocket motors and aerospike nozzles. This synthesis of technologies is unique to the MUPHyN thruster design and no comparable work has been published in the open literature.

Reliability of digital ulcer definitions as proposed by the UK Scleroderma Study Group: A challenge for clinical trial design.

PubMed

Hughes, Michael; Tracey, Andrew; Bhushan, Monica; Chakravarty, Kuntal; Denton, Christopher P; Dubey, Shirish; Guiducci, Serena; Muir, Lindsay; Ong, Voon; Parker, Louise; Pauling, John D; Prabu, Athiveeraramapandian; Rogers, Christine; Roberts, Christopher; Herrick, Ariane L

2018-06-01

The reliability of clinician grading of systemic sclerosis-related digital ulcers has been reported to be poor to moderate at best, which has important implications for clinical trial design. The aim of this study was to examine the reliability of new proposed UK Scleroderma Study Group digital ulcer definitions among UK clinicians with an interest in systemic sclerosis. Raters graded (through a custom-built interface) 90 images (80 unique and 10 repeat) of a range of digital lesions collected from patients with systemic sclerosis. Lesions were graded on an ordinal scale of severity: 'no ulcer', 'healed ulcer' or 'digital ulcer'. A total of 23 clinicians - 18 rheumatologists, 3 dermatologists, 1 hand surgeon and 1 specialist rheumatology nurse - completed the study. A total of 2070 (1840 unique + 230 repeat) image gradings were obtained. For intra-rater reliability, across all images, the overall weighted kappa coefficient was high (0.71) and was moderate (0.55) when averaged across individual raters. Overall inter-rater reliability was poor (0.15). Although our proposed digital ulcer definitions had high intra-rater reliability, the overall inter-rater reliability was poor. Our study highlights the challenges of digital ulcer assessment by clinicians with an interest in systemic sclerosis and provides a number of useful insights for future clinical trial design. Further research is warranted to improve the reliability of digital ulcer definition/rating as an outcome measure in clinical trials, including examining the role for objective measurement techniques, and the development of digital ulcer patient-reported outcome measures.

Development and testing of a novel subsea production system and control buoy

DOE Office of Scientific and Technical Information (OSTI.GOV)

NONE

1997-04-01

The remoteness of Australia`s northwest shelf presents challenges for the economic viability of offshore resource-development projects. Accordingly, the East Spar development has been designed to minimize capital and life-cycle costs to ensure the long-term viability of this offshore gas field. The offshore facilities are made up of a novel unmanned navigation, communication, and control (NCC) buoy linked to a subsea-production system that includes heat exchangers, insert-retrievable choke valves, multiphase flow-meters, and an on-line pipeline-corrosion monitoring system. The technological building blocks for field development are industry proved. However, the novel arrangement of this proven technology into a remotely controlled, self-contained, minimum-maintenancemore » unmanned facility is unique and has led to many challenges during the design and testing of the NCC buoy and subsea facilities. Among these challenges has been the formulation of an integration test program of the NCC buoy and subsea hardware that proves, as far as reasonably possible, the complete functionality of each equipment item and interface, subject to constraints imposed by schedule, cost, and logistics. Integration testing is particularly important to confirm that the offshore facilities will operate as designed with sufficient reliability and system redundancy to ensure continuous operation throughout the 20-year field life.« less

Vertical interferometer workstation for testing large spherical optics

NASA Astrophysics Data System (ADS)

Truax, B.

2013-09-01

The design of an interferometer workstation for the testing of large concave and convex spherical optics is presented. The workstation handles optical components and mounts up to 425 mm in diameter with mass of up to 40 kg with 6 axes of adjustment. A unique method for the implementation of focus, roll and pitch was used allowing for extremely precise adjustment. The completed system includes transmission spheres with f-numbers from f/1.6 to f/0.82 incorporating reference surface diameters of up to 306 mm and surface accuracies of better than 63 nm PVr. The design challenges and resulting solutions are discussed. System performance results are presented.

Porous Hydrogen-Bonded Organic Frameworks.

PubMed

Han, Yi-Fei; Yuan, Ying-Xue; Wang, Hong-Bo

2017-02-13

Ordered porous solid-state architectures constructed via non-covalent supramolecular self-assembly have attracted increasing interest due to their unique advantages and potential applications. Porous metal-coordination organic frameworks (MOFs) are generated by the assembly of metal coordination centers and organic linkers. Compared to MOFs, porous hydrogen-bonded organic frameworks (HOFs) are readily purified and recovered via simple recrystallization. However, due to lacking of sufficiently ability to orientate self-aggregation of building motifs in predictable manners, rational design and preparation of porous HOFs are still challenging. Herein, we summarize recent developments about porous HOFs and attempt to gain deeper insights into the design strategies of basic building motifs.

The Undiagnosed Diseases Program Integrated Collaboration System (UDPICS): One Program’s Experience Developing Custom Software to Support Research for Complex-Disease Families

PubMed Central

Guzman, Jessica; Lee, Elizabeth; Draper, David; Valivullah, Zaheer; Yu, Guoyun; Sincan, Murat; Gahl, William A.; Adams, David R.

2015-01-01

The Undiagnosed Diseases Program (UDP) was started in 2008 with the goals of making diagnoses and facilitating related translational research. The individuals and families seen by the UDP are often unique and medically complex. Approximately 40% of UDP cases are pediatric. The Undiagnosed Diseases Program Integrated Collaboration System (UDPICS) was designed to create a collaborative workspace for researchers, clinicians and families. We describe our progress in developing the system to date, focusing on design rationale, challenges and issues that are likely to be common in the development of similar systems in the future. PMID:27417368

Nanostructured thick 3D nanofibrous scaffold can induce bone.

PubMed

Eap, Sandy; Morand, David; Clauss, François; Huck, Olivier; Stoltz, Jean-François; Lutz, Jean-Christophe; Gottenberg, Jacques-Eric; Benkirane-Jessel, Nadia; Keller, Laetitia; Fioretti, Florence

2015-01-01

Designing unique nanostructured biomimetic materials is a new challenge in modern regenerative medicine. In order to develop functional substitutes for damaged organs or tissues, several methods have been used to create implants able to regenerate robust and durable bone. Electrospinning produces nonwoven scaffolds based on polymer nanofibers mimicking the fibrillar organization of bone extracellular matrix. Here, we describe a biomimetic 3D thick nanofibrous scaffold obtained by electrospinning of the biodegradable, bioresorbable and FDA-approved polymer, poly(ε-caprolactone). Such scaffold presents a thickness reaching one centimeter. We report here the demonstration that the designed nanostructured implant is able to induce in vivo bone regeneration.

Overview of the Altair Lunar Lander Thermal Control System Design

NASA Technical Reports Server (NTRS)

Stephan, Ryan A.

2010-01-01

NASA's Constellation Program has been developed to successfully return humans to the Lunar surface by 2020. The Constellation Program includes several different project offices including Altair, which is the next generation Lunar Lander. The planned Altair missions are very different than the Lunar missions accomplished during the Apollo era. These differences have resulted in a significantly different thermal control system architecture. The current paper will summarize the Altair mission architecture and the various operational phases. In addition, the derived thermal requirements will be presented. The paper will conclude with a brief description of the thermal control system designed to meet these unique and challenging thermal requirements.

Space station structures and dynamics test program

NASA Technical Reports Server (NTRS)

Moore, Carleton J.; Townsend, John S.; Ivey, Edward W.

1987-01-01

The design, construction, and operation of a low-Earth orbit space station poses unique challenges for development and implementation of new technology. The technology arises from the special requirement that the station be built and constructed to function in a weightless environment, where static loads are minimal and secondary to system dynamics and control problems. One specific challenge confronting NASA is the development of a dynamics test program for: (1) defining space station design requirements, and (2) identifying the characterizing phenomena affecting the station's design and development. A general definition of the space station dynamic test program, as proposed by MSFC, forms the subject of this report. The test proposal is a comprehensive structural dynamics program to be launched in support of the space station. The test program will help to define the key issues and/or problems inherent to large space structure analysis, design, and testing. Development of a parametric data base and verification of the math models and analytical analysis tools necessary for engineering support of the station's design, construction, and operation provide the impetus for the dynamics test program. The philosophy is to integrate dynamics into the design phase through extensive ground testing and analytical ground simulations of generic systems, prototype elements, and subassemblies. On-orbit testing of the station will also be used to define its capability.

Modified ACES Portable Life Support Integration, Design, and Testing for Exploration Missions

NASA Technical Reports Server (NTRS)

Kelly, Cody

2014-01-01

NASA's next generation of exploration missions provide a unique challenge to designers of EVA life support equipment, especially in a fiscally-constrained environment. In order to take the next steps of manned space exploration, NASA is currently evaluating the use of the Modified ACES (MACES) suit in conjunction with the Advanced Portable Life Support System (PLSS) currently under development. This paper will detail the analysis and integration of the PLSS thermal and ventilation subsystems into the MACES pressure garment, design of prototype hardware, and hardware-in-the-loop testing during the spring 2014 timeframe. Prototype hardware was designed with a minimal impact philosophy in order to mitigate design constraints becoming levied on either the advanced PLSS or MACES subsystems. Among challenges faced by engineers were incorporation of life support thermal water systems into the pressure garment cavity, operational concept definition between vehicle/portable life support system hardware, and structural attachment mechanisms while still enabling maximum EVA efficiency from a crew member's perspective. Analysis was completed in late summer 2013 to 'bound' hardware development, with iterative analysis cycles throughout the hardware development process. The design effort will cumulate in the first ever manned integration of NASA's advanced PLSS system with a pressure garment originally intended primarily for use in a contingency survival scenario.

GMTIFS: challenging optical design problems and their solutions for the GMT integral-field spectrograph

NASA Astrophysics Data System (ADS)

Hart, John; Bloxham, Gabe; Boz, Robert; Espeland, Brady; Sharp, Robert

2016-08-01

GMTIFS is a first generation instrument for the Giant Magellan Telescope (GMT). It is a combined Imager and Integral Field Spectrograph (IFS) designed to work with the Adaptive Optics (AO) Systems of the GMT. Working at the diffraction limit of the GMT and satisfying the challenging AO interface requirements and constraints results in unique optical challenges. We describe two of these challenges and how we have addressed them. The GMT has a direct feed architecture that maximizes transmission and reduces emissivity. This means that the cryostat window is tilted to reflect visual wavelengths to the external Visual Wave Front Subsystem (VWS). For a plane-parallel window, this tilt causes astigmatism in the transmitted beam that must be corrected. A corrective system using two plates, tilted and slightly wedged in opposite directions, is used. Geometry and performance of the system is described. Another challenging problem is the optical design of the anamorphic field projector. The Integral Field Unit of GMTIFS requires that a small field delivered to it be projected onto an Image Slicer at much larger scale, with the magnification in the spectral direction being twice that in the spatial direction so that the spaxels are square when referred to the sky. Output images must be coincident in the spectral and spatial projections in both the field and pupil domains. Additionally, field and pupil image locations must be independently controllable so that they can be made coincident for interchangeable units that provide a range of output field scales. A two-mirror system that satisfies these requirements is described.

Technology Challenges for Deep-Throttle Cryogenic Engines for Space Exploration

NASA Technical Reports Server (NTRS)

Brown, Kendall K.; Nelson, Karl W.

2005-01-01

Historically, cryogenic rocket engines have not been used for in-space applications due to their additional complexity, the mission need for high reliability, and the challenges of propellant boil-off. While the mission and vehicle architectures are not yet defined for the lunar and Martian robotic and human exploration objectives, cryogenic rocket engines offer the potential for higher performance and greater architecture/mission flexibility. In-situ cryogenic propellant production could enable a more robust exploration program by significantly reducing the propellant mass delivered to low earth orbit, thus warranting the evaluation of cryogenic rocket engines versus the hypergolic bi-propellant engines used in the Apollo program. A multi-use engine. one which can provide the functionality that separate engines provided in the Apollo mission architecture, is desirable for lunar and Mars exploration missions because it increases overall architecture effectiveness through commonality and modularity. The engine requirement derivation process must address each unique mission application and each unique phase within each mission. The resulting requirements, such as thrust level, performance, packaging, bum duration, number of operations; required impulses for each trajectory phase; operation after extended space or surface exposure; availability for inspection and maintenance; throttle range for planetary descent, ascent, acceleration limits and many more must be addressed. Within engine system studies, the system and component technology, capability, and risks must be evaluated and a balance between the appropriate amount of technology-push and technology-pull must be addressed. This paper will summarize many of the key technology challenges associated with using high-performance cryogenic liquid propellant rocket engine systems and components in the exploration program architectures. The paper is divided into two areas. The first area describes how the mission requirements affect the engine system requirements and create system level technology challenges. An engine system architecture for multiple applications or a family of engines based upon a set of core technologies, design, and fabrication approaches may reduce overall programmatic cost and risk. The engine system discussion will also address the characterization of engine cycle figures of merit, configurations, and design approaches for some in-space vehicle alternatives under consideration. The second area evaluates the component-level technology challenges induced from the system requirements. Component technology issues are discussed addressing injector, thrust chamber, ignition system, turbopump assembly, and valve design for the challenging requirements of high reliability, robustness, fault tolerance, deep throttling, reasonable performance (with respect to weight and specific impulse).

Technology Challenges for Deep-Throttle Cryogenic Engines for Space Exploration

NASA Astrophysics Data System (ADS)

Brown, Kendall K.; Nelson, Karl W.

2005-02-01

Historically, cryogenic rocket engines have not been used for in-space applications due to their additional complexity, the mission need for high reliability, and the challenges of propellant boil-off. While the mission and vehicle architectures are not yet defined for the lunar and Martian robotic and human exploration objectives, cryogenic rocket engines offer the potential for higher performance and greater architecture/mission flexibility. In-situ cryogenic propellant production could enable a more robust exploration program by significantly reducing the propellant mass delivered to low earth orbit, thus warranting the evaluation of cryogenic rocket engines versus the hypergolic bipropellant engines used in the Apollo program. A multi-use engine, one which can provide the functionality that separate engines provided in the Apollo mission architecture, is desirable for lunar and Mars exploration missions because it increases overall architecture effectiveness through commonality and modularity. The engine requirement derivation process must address each unique mission application and each unique phase within each mission. The resulting requirements, such as thrust level, performance, packaging, burn duration, number of operations; required impulses for each trajectory phase; operation after extended space or surface exposure; availability for inspection and maintenance; throttle range for planetary descent, ascent, acceleration limits and many more must be addressed. Within engine system studies, the system and component technology, capability, and risks must be evaluated and a balance between the appropriate amount of technology-push and technology-pull must be addressed. This paper will summarize many of the key technology challenges associated with using high-performance cryogenic liquid propellant rocket engine systems and components in the exploration program architectures. The paper is divided into two areas. The first area describes how the mission requirements affect the engine system requirements and create system level technology challenges. An engine system architecture for multiple applications or a family of engines based upon a set of core technologies, design, and fabrication approaches may reduce overall programmatic cost and risk. The engine system discussion will also address the characterization of engine cycle figures of merit, configurations, and design approaches for some in-space vehicle alternatives under consideration. The second area evaluates the component-level technology challenges induced from the system requirements. Component technology issues are discussed addressing injector, thrust chamber, ignition system, turbopump assembly, and valve design for the challenging requirements of high reliability, robustness, fault tolerance, deep throttling, reasonable performance (with respect to weight and specific impulse).

Spacecraft Design Considerations for Piloted Reentry and Landing

NASA Technical Reports Server (NTRS)

Stroud, Kenneth J.; Klaus, David M.

2006-01-01

With the end of the Space Shuttle era anticipated in this decade and the requirements for the Crew Exploration Vehicle (CEV) now being defined, an opportune window exists for incorporating 'lessons learned' from relevant aircraft and space flight experience into the early stages of designing the next generation of human spacecraft. This includes addressing not only the technological and overall mission challenges, but also taking into account the comprehensive effects that space flight has on the pilot, all of which must be balanced to ensure the safety of the crew. This manuscript presents a unique and timely overview of a multitude of competing, often unrelated, requirements and constraints governing spacecraft design that must be collectively considered in order to ensure the success of future space exploration missions.

Transitioning Rationally Designed Catalytic Materials to Real 'Working' Catalysts Produced at Commercial Scale: Nanoparticle Materials

DOE Office of Scientific and Technical Information (OSTI.GOV)

Schaidle, Joshua A.; Habas, Susan E.; Baddour, Frederick G.

Catalyst design, from idea to commercialization, requires multi-disciplinary scientific and engineering research and development over 10-20 year time periods. Historically, the identification of new or improved catalyst materials has largely been an empirical trial-and-error process. However, advances in computational capabilities (new tools and increased processing power) coupled with new synthetic techniques have started to yield rationally-designed catalysts with controlled nano-structures and tailored properties. This technological advancement represents an opportunity to accelerate the catalyst development timeline and to deliver new materials that outperform existing industrial catalysts or enable new applications, once a number of unique challenges associated with the scale-up ofmore » nano-structured materials are overcome.« less

Defining Operational Space Suit Requirements for Commercial Orbital Spaceflight

NASA Technical Reports Server (NTRS)

Alpert, Brian K.

2015-01-01

As the commercial spaceflight industry transitions from suborbital brevity to orbital outposts, spacewalking will become a major consideration for tourists, scientists, and hardware providers. The challenge exists to develop a space suit designed for the orbital commercial spaceflight industry. The unique needs and requirements of this industry will drive space suit designs and costs that are unlike any existing product. Commercial space tourists will pay for the experience of a lifetime, while scientists may not be able to rely on robotics for all operations and external hardware repairs. This study was aimed at defining space suit operational and functional needs across the spectrum of spacewalk elements, identifying technical design drivers and establishing appropriate options. Recommendations from the analysis are offered for consideration

Requirements for facilities and measurement techniques to support CFD development for hypersonic aircraft

NASA Technical Reports Server (NTRS)

Sellers, William L., III; Dwoyer, Douglas L.

1992-01-01

The design of a hypersonic aircraft poses unique challenges to the engineering community. Problems with duplicating flight conditions in ground based facilities have made performance predictions risky. Computational fluid dynamics (CFD) has been proposed as an additional means of providing design data. At the present time, CFD codes are being validated based on sparse experimental data and then used to predict performance at flight conditions with generally unknown levels of uncertainty. This paper will discuss the facility and measurement techniques that are required to support CFD development for the design of hypersonic aircraft. Illustrations are given of recent success in combining experimental and direct numerical simulation in CFD model development and validation for hypersonic perfect gas flows.

Empowering Older Patients to Engage in Self Care: Designing an Interactive Robotic Device

PubMed Central

Tiwari, Priyadarshi; Warren, Jim; Day, Karen

2011-01-01

Objectives: To develop and test an interactive robot mounted computing device to support medication management as an example of a complex self-care task in older adults. Method: A Grounded Theory (GT), Participatory Design (PD) approach was used within three Action Research (AR) cycles to understand design requirements and test the design configuration addressing the unique task requirements. Results: At the end of the first cycle a conceptual framework was evolved. The second cycle informed architecture and interface design. By the end of third cycle residents successfully interacted with the dialogue system and were generally satisfied with the robot. The results informed further refinement of the prototype. Conclusion: An interactive, touch screen based, robot-mounted information tool can be developed to support healthcare needs of older people. Qualitative methods such as the hybrid GT-PD-AR approach may be particularly helpful for innovating and articulating design requirements in challenging situations. PMID:22195203

Empowering older patients to engage in self care: designing an interactive robotic device.

PubMed

Tiwari, Priyadarshi; Warren, Jim; Day, Karen

2011-01-01

To develop and test an interactive robot mounted computing device to support medication management as an example of a complex self-care task in older adults. A Grounded Theory (GT), Participatory Design (PD) approach was used within three Action Research (AR) cycles to understand design requirements and test the design configuration addressing the unique task requirements. At the end of the first cycle a conceptual framework was evolved. The second cycle informed architecture and interface design. By the end of third cycle residents successfully interacted with the dialogue system and were generally satisfied with the robot. The results informed further refinement of the prototype. An interactive, touch screen based, robot-mounted information tool can be developed to support healthcare needs of older people. Qualitative methods such as the hybrid GT-PD-AR approach may be particularly helpful for innovating and articulating design requirements in challenging situations.

Wavefront modulation and subwavelength diffractive acoustics with an acoustic metasurface.

PubMed

Xie, Yangbo; Wang, Wenqi; Chen, Huanyang; Konneker, Adam; Popa, Bogdan-Ioan; Cummer, Steven A

2014-11-24

Metasurfaces are a family of novel wavefront-shaping devices with planar profile and subwavelength thickness. Acoustic metasurfaces with ultralow profile yet extraordinary wave manipulating properties would be highly desirable for improving the performance of many acoustic wave-based applications. However, designing acoustic metasurfaces with similar functionality to their electromagnetic counterparts remains challenging with traditional metamaterial design approaches. Here we present a design and realization of an acoustic metasurface based on tapered labyrinthine metamaterials. The demonstrated metasurface can not only steer an acoustic beam as expected from the generalized Snell's law, but also exhibits various unique properties such as conversion from propagating wave to surface mode, extraordinary beam-steering and apparent negative refraction through higher-order diffraction. Such designer acoustic metasurfaces provide a new design methodology for acoustic signal modulation devices and may be useful for applications such as acoustic imaging, beam steering, ultrasound lens design and acoustic surface wave-based applications.

The REFLECT statement: methods and processes of creating reporting guidelines for randomized controlled trials for livestock and food safety.

PubMed

O'Connor, A M; Sargeant, J M; Gardner, I A; Dickson, J S; Torrence, M E; Dewey, C E; Dohoo, I R; Evans, R B; Gray, J T; Greiner, M; Keefe, G; Lefebvre, S L; Morley, P S; Ramirez, A; Sischo, W; Smith, D R; Snedeker, K; Sofos, J; Ward, M P; Wills, R

2010-01-01

The conduct of randomized controlled trials in livestock with production, health, and food-safety outcomes presents unique challenges that may not be adequately reported in trial reports. The objective of this project was to modify the CONSORT (Consolidated Standards of Reporting Trials) statement to reflect the unique aspects of reporting these livestock trials. A two-day consensus meeting was held on November 18-19, 2008 in Chicago, IL, United States of America, to achieve the objective. Prior to the meeting, a Web-based survey was conducted to identify issues for discussion. The 24 attendees were biostatisticians, epidemiologists, food-safety researchers, livestock-production specialists, journal editors, assistant editors, and associate editors. Prior to the meeting, the attendees completed a Web-based survey indicating which CONSORT statement items may need to be modified to address unique issues for livestock trials. The consensus meeting resulted in the production of the REFLECT (Reporting Guidelines For Randomized Control Trials) statement for livestock and food safety (LFS) and 22-item checklist. Fourteen items were modified from the CONSORT checklist, and an additional sub-item was proposed to address challenge trials. The REFLECT statement proposes new terminology, more consistent with common usage in livestock production, to describe study subjects. Evidence was not always available to support modification to or inclusion of an item. The use of the REFLECT statement, which addresses issues unique to livestock trials, should improve the quality of reporting and design for trials reporting production, health, and food-safety outcomes.

The REFLECT statement: methods and processes of creating reporting guidelines for randomized controlled trials for livestock and food safety by modifying the CONSORT statement.

PubMed

O'Connor, A M; Sargeant, J M; Gardner, I A; Dickson, J S; Torrence, M E; Dewey, C E; Dohoo, I R; Evans, R B; Gray, J T; Greiner, M; Keefe, G; Lefebvre, S L; Morley, P S; Ramirez, A; Sischo, W; Smith, D R; Snedeker, K; Sofos, J; Ward, M P; Wills, R

2010-03-01

The conduct of randomized controlled trials in livestock with production, health and food-safety outcomes presents unique challenges that may not be adequately reported in trial reports. The objective of this project was to modify the CONSORT (Consolidated Standards of Reporting Trials) statement to reflect the unique aspects of reporting these livestock trials. A 2-day consensus meeting was held on 18-19 November 2008 in Chicago, IL, USA, to achieve the objective. Prior to the meeting, a Web-based survey was conducted to identify issues for discussion. The 24 attendees were biostatisticians, epidemiologists, food-safety researchers, livestock-production specialists, journal editors, assistant editors and associate editors. Prior to the meeting, the attendees completed a Web-based survey indicating which CONSORT statement items may need to be modified to address unique issues for livestock trials. The consensus meeting resulted in the production of the REFLECT (Reporting Guidelines for Randomized Control Trials) statement for livestock and food safety and 22-item checklist. Fourteen items were modified from the CONSORT checklist and an additional sub-item was proposed to address challenge trials. The REFLECT statement proposes new terminology, more consistent with common usage in livestock production, to describe study subjects. Evidence was not always available to support modification to or inclusion of an item. The use of the REFLECT statement, which addresses issues unique to livestock trials, should improve the quality of reporting and design for trials reporting production, health and food-safety outcomes.

The REFLECT statement: methods and processes of creating reporting guidelines for randomized controlled trials for livestock and food safety.

PubMed

O'Connor, A M; Sargeant, J M; Gardner, I A; Dickson, J S; Torrence, M E; Dewey, C E; Dohoo, I R; Evans, R B; Gray, J T; Greiner, M; Keefe, G; Lefebvre, S L; Morley, P S; Ramirez, A; Sischo, W; Smith, D R; Snedeker, K; Sofos, J N; Ward, M P; Wills, R

2010-01-01

The conduct of randomized controlled trials in livestock with production, health, and food-safety outcomes presents unique challenges that may not be adequately reported in trial reports. The objective of this project was to modify the CONSORT (Consolidated Standards of Reporting Trials) statement to reflect the unique aspects of reporting these livestock trials. A two-day consensus meeting was held on November 18-19, 2008 in Chicago, Ill, United States of America, to achieve the objective. Prior to the meeting, a Web-based survey was conducted to identify issues for discussion. The 24 attendees were biostatisticians, epidemiologists, food-safety researchers, livestock production specialists, journal editors, assistant editors, and associate editors. Prior to the meeting, the attendees completed a Web-based survey indicating which CONSORT statement items may need to be modified to address unique issues for livestock trials. The consensus meeting resulted in the production of the REFLECT (Reporting Guidelines for Randomized Control Trials) statement for livestock and food safety (LFS) and 22-item checklist. Fourteen items were modified from the CONSORT checklist, and an additional sub-item was proposed to address challenge trials. The REFLECT statement proposes new terminology, more consistent with common usage in livestock production, to describe study subjects. Evidence was not always available to support modification to or inclusion of an item. The use of the REFLECT statement, which addresses issues unique to livestock trials, should improve the quality of reporting and design for trials reporting production, health, and food-safety outcomes.

Multi-level Simulation of a Real Time Vibration Monitoring System Component

NASA Technical Reports Server (NTRS)

Robertson, Bryan A.; Wilkerson, Delisa

2005-01-01

This paper describes the development of a custom built Digital Signal Processing (DSP) printed circuit board designed to implement the Advanced Real Time Vibration Monitoring Subsystem proposed by Marshall Space Flight Center (MSFC) Transportation Directorate in 2000 for the Space Shuttle Main Engine Advanced Health Management System (AHMS). This Real Time Vibration Monitoring System (RTVMS) is being developed for ground use as part of the AHMS Health Management Computer-Integrated Rack Assembly (HMC-IRA). The HMC-IRA RTVMS design contains five DSPs which are highly interconnected through individual communication ports, shared memory, and a unique communication router that allows all the DSPs to receive digitized data fiom two multi-channel analog boards simultaneously. This paper will briefly cover the overall board design but will focus primarily on the state-of-the-art simulation environment within which this board was developed. This 16-layer board with over 1800 components and an additional mezzanine card has been an extremely challenging design. Utilization of a Mentor Graphics simulation environment provided the unique board and system level simulation capability to ascertain any timing or functional concerns before production. By combining VHDL, Synopsys Software and Hardware Models, and the Mentor Design Capture Environment, multiple simulations were developed to verify the RTVMS design. This multi-level simulation allowed the designers to achieve complete operability without error the first time the RTVMS printed circuit board was powered. The HMC-IRA design has completed all engineering and deliverable unit testing. P

Multi-level Simulation of a Real Time Vibration Monitoring System Component

NASA Technical Reports Server (NTRS)

Roberston, Bryan; Wilkerson, DeLisa

2004-01-01

This paper describes the development of a custom built Digital Signal Processing (DSP) printed circuit board designed to implement the Advanced Real Time Vibration Monitoring Subsystem proposed by MSFC Transportation Directorate in 2000 for the Space Shuttle Main Engine Advanced Health Management System (AHMS). This Real Time Vibration Monitoring System (RTVMS) is being developed for ground use as part of the AHMS Health Management Computer-Integrated Rack Assembly (HMC-IRA). The HMC-IRA RTVMS design contains five DSPs which are highly interconnected through individual communication ports, shared memory, and a unique communication router that allows all the DSPs to receive digitized data from two multi-channel analog boards simultaneously. This paper will briefly cover the overall board design but will focus primarily on the state-of-the-art simulation environment within which this board was developed. This 16-layer board with over 1800 components and an additional mezzanine card has been an extremely challenging design. Utilization of a Mentor Graphics simulation environment provided the unique board and system level simulation capability to ascertain any timing or functional concerns before production. By combining VHDL, Synopsys Software and Hardware Models, and the Mentor Design Capture Environment, multiple simulations were developed to verify the RTVMS design. This multi-level simulation allowed the designers to achieve complete operability without error the first time the RTVMS printed circuit board was powered. The HMCIRA design has completed all engineering unit testing and the deliverable unit is currently under development.

Design and development an insect-inspired humanoid gripper that is structurally sound, yet very flexible

NASA Astrophysics Data System (ADS)

Hajjaj, S.; Pun, N.

2013-06-01

One of the biggest challenges in mechanical robotics design is the balance between structural integrity and flexibility. An industrial robotic gripper could be technically advanced, however it contains only 1 Degree of Freedom (DOF). If one is to add more DOFs the design would become complex. On the other hand, the human wrist and fingers contain 23 DOFs, and is very lightweight and highly flexible. Robotics are becoming more and more part of our social life, they are more and more being incorporated in social, medical, and personal application. Therefore, for such robots to be effective, they need to mimic human performance, both in performance as well as in mechanical design. In this work, a Humanoid Gripper is designed and built to mimic a simplified version of a human wrist and fingers. This is attempted by mimicking insect and human designs of grippes. The main challenge was to insure that the gripper is structurally sound, but at the same time flexible and lightweight. A combination of light weight material and a unique design of finger actuators were applied. The gripper is controlled by a PARALLAX servo controller 28823 (PSCI), which mounted on the assembly itself. At the end, a 6 DOF humanoid gripper made of lightweight material, similar in size to the human arm, and is able to carry a weight of 1 Kg has been designed and built.

Quantitative Approaches to Group Research: Suggestions for Best Practices

ERIC Educational Resources Information Center

McCarthy, Christopher J.; Whittaker, Tiffany A.; Boyle, Lauren H.; Eyal, Maytal

2017-01-01

Rigorous scholarship is essential to the continued growth of group work, yet the unique nature of this counseling specialty poses challenges for quantitative researchers. The purpose of this proposal is to overview unique challenges to quantitative research with groups in the counseling field, including difficulty in obtaining large sample sizes…

SVAS3: Strain Vector Aided Sensorization of Soft Structures.

PubMed

Culha, Utku; Nurzaman, Surya G; Clemens, Frank; Iida, Fumiya

2014-07-17

Soft material structures exhibit high deformability and conformability which can be useful for many engineering applications such as robots adapting to unstructured and dynamic environments. However, the fact that they have almost infinite degrees of freedom challenges conventional sensory systems and sensorization approaches due to the difficulties in adapting to soft structure deformations. In this paper, we address this challenge by proposing a novel method which designs flexible sensor morphologies to sense soft material deformations by using a functional material called conductive thermoplastic elastomer (CTPE). This model-based design method, called Strain Vector Aided Sensorization of Soft Structures (SVAS3), provides a simulation platform which analyzes soft body deformations and automatically finds suitable locations for CTPE-based strain gauge sensors to gather strain information which best characterizes the deformation. Our chosen sensor material CTPE exhibits a set of unique behaviors in terms of strain length electrical conductivity, elasticity, and shape adaptability, allowing us to flexibly design sensor morphology that can best capture strain distributions in a given soft structure. We evaluate the performance of our approach by both simulated and real-world experiments and discuss the potential and limitations.

Trajectory Optimization of Electric Aircraft Subject to Subsystem Thermal Constraints

NASA Technical Reports Server (NTRS)

Falck, Robert D.; Chin, Jeffrey C.; Schnulo, Sydney L.; Burt, Jonathan M.; Gray, Justin S.

2017-01-01

Electric aircraft pose a unique design challenge in that they lack a simple way to reject waste heat from the power train. While conventional aircraft reject most of their excess heat in the exhaust stream, for electric aircraft this is not an option. To examine the implications of this challenge on electric aircraft design and performance, we developed a model of the electric subsystems for the NASA X-57 electric testbed aircraft. We then coupled this model with a model of simple 2D aircraft dynamics and used a Legendre-Gauss-Lobatto collocation optimal control approach to find optimal trajectories for the aircraft with and without thermal constraints. The results show that the X-57 heat rejection systems are well designed for maximum-range and maximum-efficiency flight, without the need to deviate from an optimal trajectory. Stressing the thermal constraints by reducing the cooling capacity or requiring faster flight has a minimal impact on performance, as the trajectory optimization technique is able to find flight paths which honor the thermal constraints with relatively minor deviations from the nominal optimal trajectory.

Development of a cryogenic capillary pumped loop

NASA Astrophysics Data System (ADS)

Kroliczek, Edward J.; Cullimore, Brent

1996-03-01

This paper describes the initial development of a promising new cryogenic technology. Room temperature capillary pumped loops (CPLs), a derivative of heat pipe technology, have been under development for almost two decades and are emerging as a design solution for many spacecraft thermal control problems. While cryogenic capillary pumped loops have application to passive spacecraft radiators and to long term storage of cryogenic propellants and open-cycle coolants, their application to the integration of spacecraft cryocoolers has generated the most excitement. Without moving parts or complex controls, they are able to thermally connect redundant cryocoolers to a single remote load, eliminating thermal switches and providing mechanical isolation at the same time. Development of a cryogenic CPL (CCPL) presented some unique challenges including start-up from a super-critical state, the management of parasitic heat leaks and pressure containment at ambient temperatures. These challenges have been overcome with a novel design that requires no additional devices or preconditioning for start-up. This paper describes the design concept and development and results conducted under SBIR Phase I and Phase II.

TOPICAL REVIEW: Prosthetic interfaces with the visual system: biological issues

NASA Astrophysics Data System (ADS)

Cohen, Ethan D.

2007-06-01

The design of effective visual prostheses for the blind represents a challenge for biomedical engineers and neuroscientists. Significant progress has been made in the miniaturization and processing power of prosthesis electronics; however development lags in the design and construction of effective machine brain interfaces with visual system neurons. This review summarizes what has been learned about stimulating neurons in the human and primate retina, lateral geniculate nucleus and visual cortex. Each level of the visual system presents unique challenges for neural interface design. Blind patients with the retinal degenerative disease retinitis pigmentosa (RP) are a common population in clinical trials of visual prostheses. The visual performance abilities of normals and RP patients are compared. To generate pattern vision in blind patients, the visual prosthetic interface must effectively stimulate the retinotopically organized neurons in the central visual field to elicit patterned visual percepts. The development of more biologically compatible methods of stimulating visual system neurons is critical to the development of finer spatial percepts. Prosthesis electrode arrays need to adapt to different optimal stimulus locations, stimulus patterns, and patient disease states.

Model-based nonlinear control of hydraulic servo systems: Challenges, developments and perspectives

NASA Astrophysics Data System (ADS)

Yao, Jianyong

2018-06-01

Hydraulic servo system plays a significant role in industries, and usually acts as a core point in control and power transmission. Although linear theory-based control methods have been well established, advanced controller design methods for hydraulic servo system to achieve high performance is still an unending pursuit along with the development of modern industry. Essential nonlinearity is a unique feature and makes model-based nonlinear control more attractive, due to benefit from prior knowledge of the servo valve controlled hydraulic system. In this paper, a discussion for challenges in model-based nonlinear control, latest developments and brief perspectives of hydraulic servo systems are presented: Modelling uncertainty in hydraulic system is a major challenge, which includes parametric uncertainty and time-varying disturbance; some specific requirements also arise ad hoc difficulties such as nonlinear friction during low velocity tracking, severe disturbance, periodic disturbance, etc.; to handle various challenges, nonlinear solutions including parameter adaptation, nonlinear robust control, state and disturbance observation, backstepping design and so on, are proposed and integrated, theoretical analysis and lots of applications reveal their powerful capability to solve pertinent problems; and at the end, some perspectives and associated research topics (measurement noise, constraints, inner valve dynamics, input nonlinearity, etc.) in nonlinear hydraulic servo control are briefly explored and discussed.

Manufacturing of Wearable Sensors for Human Health and Performance Monitoring

NASA Astrophysics Data System (ADS)

Alizadeh, Azar

2015-03-01

Continuous monitoring of physiological and biological parameters is expected to improve performance and medical outcomes by assessing overall health status and alerting for life-saving interventions. Continuous monitoring of these parameters requires wearable devices with an appropriate form factor (lightweight, comfortable, low energy consuming and even single-use) to avoid disrupting daily activities thus ensuring operation relevance and user acceptance. Many previous efforts to implement remote and wearable sensors have suffered from high cost and poor performance, as well as low clinical and end-use acceptance. New manufacturing and system level design approaches are needed to make the performance and clinical benefits of these sensors possible while satisfying challenging economic, regulatory, clinical, and user-acceptance criteria. In this talk we will review several recent design and manufacturing efforts aimed at designing and building prototype wearable sensors. We will discuss unique opportunities and challenges provided by additive manufacturing, including 3D printing, to drive innovation through new designs, faster prototyping and manufacturing, distributed networks, and new ecosystems. We will also show alternative hybrid self-assembly based integration techniques for low cost large scale manufacturing of single use wearable devices. Coauthors: Prabhjot Singh and Jeffrey Ashe.

Total Quality Management: A Unique Challenge For Behavioral Science Researchers,

DTIC Science & Technology

Quality Management (TQM) programs in industry and government. The essence of TQM involves respect for personal choice and the participation of every level of workers in decisions which impact the organization. Typically, structured questionnaires developed by behavioral scientists are designed to be easy to summarize and generally lack any mechanism for personal comments, ideas, and suggestions. New open-ended, interactive, and iterative survey methodologies are needed to enhance creativity, encourage feedback, and foster a sense of participation. Total Quality

Electrical conductivity of KAlCl4-ZrCl4 molten mixtures

NASA Astrophysics Data System (ADS)

Salyulev, A. B.; Khokhlov, V. A.; Moskalenko, N. I.

2017-02-01

The electrical conductivity of commercially challenging KAlCl4-ZrCl4 molten mixtures has been studied as a function of temperature (in the range from 345°C to 500°C) and the ZrCl4 concentration (0‒32.5mol %) using cells of a unique design. It is found to vary in the range from 0.41 to 0.80 S cm-1, increasing with temperature or when the mole concentration of zirconium tetrachloride in molten mixtures decreases.

Findings from a national needs assessment of American Indian/Alaska native child welfare programs.

PubMed

Leake, Robin; Potter, Cathryn; Lucero, Nancy; Gardner, Jerry; Deserly, Kathy

2012-01-01

The National Child Welfare Resource Center for Tribes, a member of the Children's Bureau Child Welfare Training and Technical Assistance Network, conducted a national needs assessment of tribal child welfare. This assessment explored current practices in tribal child welfare to identify unique systemic strengths and challenges. A culturally based, multi-method design yielded findings in five areas: tribal child welfare practice, foster care and adoption, the Indian Child Welfare Act, legal and judicial, and program operations.

SHM reliability and implementation - A personal military aviation perspective

NASA Astrophysics Data System (ADS)

Lindgren, Eric A.

2016-02-01

Structural Health Monitoring has been proposed as a solution to address the needs of military aviation to reduce the time and cost to perform nondestructive inspections. While the potential to realize significant benefits exist, there are considerations that have to be addressed before such systems can be integrated into military platforms. Some considerations are pervasive to all aviation, such as how to assess the reliability and reproducible capability of these systems. However, there are other challenges unique to military aviation that must be overcome before these types of systems can be used. This presentation and paper are intended as a complement to the review of the outcome of the SAE G-11 SHM committee special workshop on SHM reliability in April of 2015. It will address challenges unique to military aviation that stem from different approaches to managing structural integrity (i.e. safety), frequency of use, design differences, various maintenance practices, and additional descriptions addressing differences in the execution of inspections. The objective of this presentation is to improve the awareness of the research and development community to the different and unique requirements found in military aviation, including the differences between countries, services, and aircraft type. This information should assist the research and development community in identifying and attacking key challenges. It is not intended to be comprehensive overview of all stakeholders' perspectives, but to serve as a launch point for additional discussion and exploration of opportunities to realize the potential of Structural Health Monitoring to assist in the management of military aviation assets. The views expressed in this publication are those of the author and do not reflect the official policy or position of the United States Air Force, Department of Defense, or the United States Government.

A qualitative analysis of barriers, challenges, and successes in meeting the needs of Hurricane Katrina evacuee families.

PubMed

Legerski, John-Paul; Vernberg, Eric M; Noland, Brian J

2012-12-01

Hurricane Katrina caused many individuals to evacuate to towns and cities throughout the United States. Psychological First Aid (PFA) is a treatment program designed to help clinicians and other disaster relief workers address the needs of adults, youth, and families immediately following disasters. We conducted focus groups with disaster relief and evacuee service providers in the Kansas City Metro Area as an exploratory study to identify their perceptions of the needs of evacuees. Participants identified a number of mental health needs, as well as displacement-related challenges, including loss of social support, material loss, unemployment, and other stressful life events that were secondary to the hurricane. Many of these needs are consistent with principles presented in the PFA manual. We also found that service providers faced unique challenges when attempting to assist evacuees. We discuss implications of these findings for treatment programs and provide suggestions for addressing barriers to care.

DOE Big Idea Summit III: Solving the Information Technology Challenge Beyond Moore's Law: A New Path to Scaling.

DOE Office of Scientific and Technical Information (OSTI.GOV)

McCormick, Frederick B.; Shalf, John; Mitchell, Alan

This report captures the initial conclusions of the DOE seven National Lab team collaborating on the “Solving the Information Technology Energy Challenge Beyond Moore’s Law” initiative from the DOE Big Idea Summit III held in April of 2016. The seven Labs held a workshop in Albuquerque, NM in late July 2016 and gathered 40 researchers into 5 working groups: 4 groups spanning the levels of the co-design framework shown below, and a 5th working group focused on extending and advancing manufacturing approaches and coupling their constraints to all of the framework levels. These working groups have identified unique capabilities withinmore » the Labs to support the key challenges of this Beyond Moore’s Law Computing (BMC) vision, as well as example first steps and potential roadmaps for technology development.« less

Healing the healer: one step at a time.

PubMed

Gershon, J Casey

2014-03-01

Health care workers have the most challenging of professions. They are expected to work long hours while demonstrating compassion and care for the patients that they serve. Although health care practitioners are among the most disciplined of working professionals, they are often some of the unhealthiest of individuals, facing enormous amounts of stress in their lives. Healing the Healer: One Step at a Time is a 6-week health fitness program. It explores the unique challenges faced in the field of health care and teaches techniques to address those challenges head on. Healing the Healer uses Nordic walking as the exercise portion of the class. The case study examines the structure, purpose, and design of this 6-week course. Special attention is given to four basic sections: balance, pacing, joy, and discipline. The arguments presented in this article are theory based and supported by case study evidence.

Closing the Gap: Supporting Patients’ Transition to Self-Management after Hospitalization

PubMed Central

Pollack, Ari H; Backonja, Uba; Miller, Andrew D.; Mishra, Sonali R.; Khelifi, Maher; Kendall, Logan; Pratt, Wanda

2016-01-01

Patients going home after a hospitalization face many challenges. This transition period exposes patients to unnecessary risks related to inadequate preparation prior to leaving the hospital, potentially leading to errors and patient harm. Although patients engaging in self-management have better health outcomes and increased self-efficacy, little is known about the processes in place to support and develop these skills for patients leaving the hospital. Through qualitative interviews and observations of 28 patients during and after their hospitalizations, we explore the challenges they face transitioning from hospital care to self-management. We identify three key elements in this process: knowledge, resources, and self-efficacy. We describe how both system and individual factors contribute to breakdowns leading to ineffective patient management. This work expands our understanding of the unique challenges faced by patients during this difficult transition and uncovers important design opportunities for supporting crucial yet unmet patient needs. PMID:27500285

Right-Handed Helical Foldamers Consisting of De Novo d -AApeptides

DOE Office of Scientific and Technical Information (OSTI.GOV)

Teng, Peng; Ma, Ning; Cerrato, Darrell Cole

New types of foldamer scaffolds are formidably challenging to design and synthesize, yet highly desirable as structural mimics of peptides/proteins with a wide repertoire of functions. In particular, the development of peptidomimetic helical foldamers holds promise for new biomaterials, catalysts, and drug molecules. Unnatural l-sulfono-γ-AApeptides were recently developed and shown to have potential applications in both biomedical and material sciences. However, d-sulfono-γ-AApeptides, the enantiomers of l-sulfono-γ-AApeptides, have never been studied due to the lack of high-resolution three-dimensional structures to guide structure-based design. Herein, we report the first synthesis and X-ray crystal structures of a series of 2:1 l-amino acid/d-sulfono-γ-AApeptide hybridmore » foldamers, and elucidate their folded conformation at the atomic level. Single-crystal X-ray crystallography indicates that this class of oligomers folds into well-defined right-handed helices with unique helical parameters. The helical structures were consistent with data obtained from solution 2D NMR, CD studies, and molecular dynamics simulations. Our findings are expected to inspire the structure-based design of this type of unique folding biopolymers for biomaterials and biomedical applications.« less

Engineering complex tissues.

PubMed

Atala, Anthony; Kasper, F Kurtis; Mikos, Antonios G

2012-11-14

Tissue engineering has emerged at the intersection of numerous disciplines to meet a global clinical need for technologies to promote the regeneration of functional living tissues and organs. The complexity of many tissues and organs, coupled with confounding factors that may be associated with the injury or disease underlying the need for repair, is a challenge to traditional engineering approaches. Biomaterials, cells, and other factors are needed to design these constructs, but not all tissues are created equal. Flat tissues (skin); tubular structures (urethra); hollow, nontubular, viscus organs (vagina); and complex solid organs (liver) all present unique challenges in tissue engineering. This review highlights advances in tissue engineering technologies to enable regeneration of complex tissues and organs and to discuss how such innovative, engineered tissues can affect the clinic.

Microstructure, Friction and Wear of Aluminum Matrix Composites

NASA Astrophysics Data System (ADS)

Florea, R. M.

2018-06-01

MMCs are made by dispersing a reinforcing material into a metal matrix. They are prepared by casting, although several technical challenges exist with casting technology. Achieving a homogeneous distribution of reinforcement within the matrix is one such challenge, and this affects directly on the properties and quality of composite. The aluminum alloy composite materials consist of high strength, high stiffness, more thermal stability, more corrosion and wear resistance, and more fatigue life. Aluminum alloy materials found to be the best alternative with its unique capacity of designing the materials to give required properties. In this work a composite is developed by adding silicon carbide in Aluminum metal matrix by mass ratio 5%, 10% and 15%. Mechanical tests such as hardness test and microstructure test are conducted.

Co-design and implementation research: challenges and solutions for ethics committees.

PubMed

Goodyear-Smith, Felicity; Jackson, Claire; Greenhalgh, Trisha

2015-11-16

Implementation science research, especially when using participatory and co-design approaches, raises unique challenges for research ethics committees. Such challenges may be poorly addressed by approval and governance mechanisms that were developed for more traditional research approaches such as randomised controlled trials. Implementation science commonly involves the partnership of researchers and stakeholders, attempting to understand and encourage uptake of completed or piloted research. A co-creation approach involves collaboration between researchers and end users from the onset, in question framing, research design and delivery, and influencing strategy, with implementation and broader dissemination strategies part of its design from gestation. A defining feature of co-creation is its emergent and adaptive nature, making detailed pre-specification of interventions and outcome measures impossible. This methodology sits oddly with ethics committee protocols that require precise pre-definition of interventions, mode of delivery, outcome measurements, and the role of study participants. But the strict (and, some would say, inflexible) requirements of ethics committees were developed for a purpose - to protect participants from harm and help ensure the rigour and transparency of studies. We propose some guiding principles to help square this circle. First, ethics committees should acknowledge and celebrate the diversity of research approaches, both formally (through training) and informally (by promoting debate and discussion); without active support, their members may not understand or value participatory designs. Second, ground rules should be established for co-design applications (e.g. how to judge when 'consultation' or 'engagement' becomes research) and communicated to committee members and stakeholders. Third, the benefits of power-sharing should be recognised and credit given to measures likely to support this important goal, especially in research with vulnerable communities. Co-design is considered best practice, for example, in research involving indigenous peoples in New Zealand, Australia and Canada.

Nano-Sized Cyclodextrin-Based Molecularly Imprinted Polymer Adsorbents for Perfluorinated Compounds—A Mini-Review

PubMed Central

Karoyo, Abdalla H.; Wilson, Lee D.

2015-01-01

Recent efforts have been directed towards the design of efficient and contaminant selective remediation technology for the removal of perfluorinated compounds (PFCs) from soils, sediments, and aquatic environments. While there is a general consensus on adsorption-based processes as the most suitable methodology for the removal of PFCs from aquatic environments, challenges exist regarding the optimal materials design of sorbents for selective uptake of PFCs. This article reviews the sorptive uptake of PFCs using cyclodextrin (CD)-based polymer adsorbents with nano- to micron-sized structural attributes. The relationship between synthesis of adsorbent materials and their structure relate to the overall sorption properties. Hence, the adsorptive uptake properties of CD-based molecularly imprinted polymers (CD-MIPs) are reviewed and compared with conventional MIPs. Further comparison is made with non-imprinted polymers (NIPs) that are based on cross-linking of pre-polymer units such as chitosan with epichlorohydrin in the absence of a molecular template. In general, MIPs offer the advantage of selectivity, chemical tunability, high stability and mechanical strength, ease of regeneration, and overall lower cost compared to NIPs. In particular, CD-MIPs offer the added advantage of possessing multiple binding sites with unique physicochemical properties such as tunable surface properties and morphology that may vary considerably. This mini-review provides a rationale for the design of unique polymer adsorbent materials that employ an intrinsic porogen via incorporation of a macrocyclic compound in the polymer framework to afford adsorbent materials with tunable physicochemical properties and unique nanostructure properties. PMID:28347047

Design and control of compliant tensegrity robots through simulation and hardware validation.

PubMed

Caluwaerts, Ken; Despraz, Jérémie; Işçen, Atıl; Sabelhaus, Andrew P; Bruce, Jonathan; Schrauwen, Benjamin; SunSpiral, Vytas

2014-09-06

To better understand the role of tensegrity structures in biological systems and their application to robotics, the Dynamic Tensegrity Robotics Lab at NASA Ames Research Center, Moffett Field, CA, USA, has developed and validated two software environments for the analysis, simulation and design of tensegrity robots. These tools, along with new control methodologies and the modular hardware components developed to validate them, are presented as a system for the design of actuated tensegrity structures. As evidenced from their appearance in many biological systems, tensegrity ('tensile-integrity') structures have unique physical properties that make them ideal for interaction with uncertain environments. Yet, these characteristics make design and control of bioinspired tensegrity robots extremely challenging. This work presents the progress our tools have made in tackling the design and control challenges of spherical tensegrity structures. We focus on this shape since it lends itself to rolling locomotion. The results of our analyses include multiple novel control approaches for mobility and terrain interaction of spherical tensegrity structures that have been tested in simulation. A hardware prototype of a spherical six-bar tensegrity, the Reservoir Compliant Tensegrity Robot, is used to empirically validate the accuracy of simulation. © 2014 The Author(s) Published by the Royal Society. All rights reserved.

The design of an air-cooled metallic high temperature radial turbine

NASA Technical Reports Server (NTRS)

Snyder, Philip H.; Roelke, Richard J.

1988-01-01

Recent trends in small advanced gas turbine engines call for higher turbine inlet temperatures. Advances in radial turbine technology have opened the way for a cooled metallic radial turbine capable of withstanding turbine inlet temperatures of 2500 F while meeting the challenge of high efficiency in this small flow size range. In response to this need, a small air-cooled radial turbine has been designed utilizing internal blade coolant passages. The coolant flow passage design is uniquely tailored to simultaneously meet rotor cooling needs and rotor fabrication constraints. The rotor flow-path design seeks to realize improved aerodynamic blade loading characteristics and high efficiency while satisfying rotor life requirements. An up-scaled version of the final engine rotor is currently under fabrication and, after instrumentation, will be tested in the warm turbine test facility at the NASA Lewis Research Center.

Design of a novel instrument for active neutron interrogation of artillery shells.

PubMed

Bélanger-Champagne, Camille; Vainionpää, Hannes; Peura, Pauli; Toivonen, Harri; Eerola, Paula; Dendooven, Peter

2017-01-01

The most common explosives can be uniquely identified by measuring the elemental H/N ratio with a precision better than 10%. Monte Carlo simulations were used to design two variants of a new prompt gamma neutron activation instrument that can achieve this precision. The instrument features an intense pulsed neutron generator with precise timing. Measuring the hydrogen peak from the target explosive is especially challenging because the instrument itself contains hydrogen, which is needed for neutron moderation and shielding. By iterative design optimization, the fraction of the hydrogen peak counts coming from the explosive under interrogation increased from [Formula: see text]% to [Formula: see text]% (statistical only) for the benchmark design. In the optimized design variants, the hydrogen signal from a high-explosive shell can be measured to a statistics-only precision better than 1% in less than 30 minutes for an average neutron production yield of 109 n/s.

Design of a novel instrument for active neutron interrogation of artillery shells

PubMed Central

Vainionpää, Hannes; Peura, Pauli; Toivonen, Harri; Eerola, Paula; Dendooven, Peter

2017-01-01

The most common explosives can be uniquely identified by measuring the elemental H/N ratio with a precision better than 10%. Monte Carlo simulations were used to design two variants of a new prompt gamma neutron activation instrument that can achieve this precision. The instrument features an intense pulsed neutron generator with precise timing. Measuring the hydrogen peak from the target explosive is especially challenging because the instrument itself contains hydrogen, which is needed for neutron moderation and shielding. By iterative design optimization, the fraction of the hydrogen peak counts coming from the explosive under interrogation increased from 53-7+7% to 74-10+8% (statistical only) for the benchmark design. In the optimized design variants, the hydrogen signal from a high-explosive shell can be measured to a statistics-only precision better than 1% in less than 30 minutes for an average neutron production yield of 109 n/s. PMID:29211773

Exploration Challenges: Transferring Ground Repair Techniques to Space Flight Application

NASA Technical Reports Server (NTRS)

McLemore, Carole A.; Kennedy, James P.; Rose, Frederick A.; Evans, Brian W.

2007-01-01

Fulfilling NASA's Vision for Space Exploration will demand an extended presence in space at distances from our home planet that exceed our current experience in space logistics and maintenance. The ability to perform repairs in lieu of the customary Orbital Replacement Unit (ORU) process where a faulty part is replaced will be elevated from contingency to routine to sustain operations. The use and cost effectiveness of field repairs for ground based operations in industry and the military have advanced with the development of technology in new materials, new repair techniques and new equipment. The unique environments, accessibility constraints and Extra Vehicular Activity (EVA) issues of space operations will require extensive assessment and evolution of these technologies to provide an equivalent and expected level of assurance to mission success. Challenges include the necessity of changes in design philosophy and policy, extremes in thermal cycling, disruptive forces (such as static charge and wind entrainment) on developed methods for control of materials, dramatically increased volatility of chemicals for cleaning and other compounds due to extremely low pressures, the limits imposed on dexterity and maneuverability by current EVA equipment and practices, and the necessity of unique verification methodology. This paper describes these challenges in and discusses the effects on the established ground techniques for repair. The paper also describes the leading repair methodology candidates and their beneficial attributes for resolving these issues with the evolution of technology.

Conceptual and methodological issues in research on mindfulness and meditation.

PubMed

Davidson, Richard J; Kaszniak, Alfred W

2015-10-01

Both basic science and clinical research on mindfulness, meditation, and related constructs have dramatically increased in recent years. However, interpretation of these research results has been challenging. The present article addresses unique conceptual and methodological problems posed by research in this area. Included among the key topics is the role of first-person experience and how it can be best studied, the challenges posed by intervention research designs in which true double-blinding is not possible, the nature of control and comparison conditions for research that includes mindfulness or other meditation-based interventions, issues in the adequate description of mindfulness and related trainings and interventions, the question of how mindfulness can be measured, questions regarding what can and cannot be inferred from self-report measures, and considerations regarding the structure of study design and data analyses. Most of these topics are germane to both basic and clinical research studies and have important bearing on the future scientific understanding of mindfulness and meditation. (c) 2015 APA, all rights reserved).

Measurement and Analysis of Extreme Wave and Ice Actions in the Great Lakes for Offshore Wind Platform Design

DOE Office of Scientific and Technical Information (OSTI.GOV)

England, Tony; van Nieuwstadt, Lin; De Roo, Roger

This project, funded by the Department of Energy as DE-EE0005376, successfully measured wind-driven lake ice forces on an offshore structure in Lake Superior through one of the coldest winters in recent history. While offshore regions of the Great Lakes offer promising opportunities for harvesting wind energy, these massive bodies of freshwater also offer extreme and unique challenges. Among these challenges is the need to anticipate forces exerted on offshore structures by lake ice. The parameters of interest include the frequency, extent, and movement of lake ice, parameters that are routinely monitored via satellite, and ice thickness, a parameter that hasmore » been monitored at discrete locations over many years and is routinely modeled. Essential relationships for these data to be of use in the design of offshore structures and the primary objective of this project are measurements of maximum forces that lake ice of known thicknesses might exert on an offshore structure.« less

ACTIVIS: Visual Exploration of Industry-Scale Deep Neural Network Models.

PubMed

Kahng, Minsuk; Andrews, Pierre Y; Kalro, Aditya; Polo Chau, Duen Horng

2017-08-30

While deep learning models have achieved state-of-the-art accuracies for many prediction tasks, understanding these models remains a challenge. Despite the recent interest in developing visual tools to help users interpret deep learning models, the complexity and wide variety of models deployed in industry, and the large-scale datasets that they used, pose unique design challenges that are inadequately addressed by existing work. Through participatory design sessions with over 15 researchers and engineers at Facebook, we have developed, deployed, and iteratively improved ACTIVIS, an interactive visualization system for interpreting large-scale deep learning models and results. By tightly integrating multiple coordinated views, such as a computation graph overview of the model architecture, and a neuron activation view for pattern discovery and comparison, users can explore complex deep neural network models at both the instance- and subset-level. ACTIVIS has been deployed on Facebook's machine learning platform. We present case studies with Facebook researchers and engineers, and usage scenarios of how ACTIVIS may work with different models.

Design colloidal particle morphology and self-assembly for coating applications

DOE Office of Scientific and Technical Information (OSTI.GOV)

Jiang, Shan; Van Dyk, Antony; Maurice, Alvin

The progressive replacement of organic solvent-based coatings by waterborne latex polymer coatings has substantially renovated the coating industry, and generated huge environmental and health benefits. Today, on top of the continuing demand for higher performance and lower costs, the coating industry faces tighter regulation and higher sustainability standards. In addition, the new waterborne coatings have created unique opportunities and challenges in terms of fundamental understanding and research development. To address these challenges, polymer latex binders with diverse particle morphologies have been developed to improve coating performance. Furthermore, colloidal self-assembly has been utilized to help manufacturers make better paint with lessmore » cost. In this report, we review the recent progress in both fundamental study and industrial application in the context of developing new generation architectural coating materials. We introduce the basic concepts in coating materials and showcase several key technologies that have been implemented to improve coating performance. As a result, these technologies also represent the most important considerations in architectural coating design.« less

Designing the future: NBIC technologies and human performance enhancement.

PubMed

Canton, James

2004-05-01

Never before has any civilization had the unique opportunity to enhance human performance on the scale that we will face in the near future. The convergence of nanotechnology, biotechnology, information technology, and cognitive science (NBIC) is creating a set of powerful tools that have the potential to significantly enhance human performance as well as transform society, science, economics, and human evolution. As the NBIC convergence becomes more understood, the possibility that we may be able to enhance human performance in the three domains of therapy, augmentation, and designed evolution will become anticipated and even expected. In addition, NBIC convergence represents entirely new challenges for scientists, policymakers, and business leaders who will have, for the first time, vast new and powerful tools to shape markets, societies, and lifestyles. The emergence of NBIC convergence will challenge us in new ways to balance risk and return, threat and opportunity, and social responsibility and competitive advantage as we step into the 21st century.

Conceptual and Methodological Issues in Research on Mindfulness and Meditation

PubMed Central

Davidson, Richard J.; Kaszniak, Alfred W.

2015-01-01

Both basic science and clinical research on mindfulness, meditation, and related constructs has dramatically increased in recent years. However, interpretation of these research results has been challenging. The present article addresses unique conceptual and methodological problems posed by research in this area. Included among the key topics is the role of first person experience and how it can be best studied; the challenges posed by intervention research designs in which true double-blinding is not possible; the nature of control and comparison conditions for research that includes mindfulness or other meditation-based interventions; issues in the adequate description of mindfulness and related trainings and interventions; the question of how mindfulness can be measured; questions regarding what can and cannot be inferred from self-report measures; and considerations regarding the structure of study design and data analyses. Most of these topics are germane to both basic and clinical research studies and have important bearing on the future scientific understanding of mindfulness and meditation. PMID:26436310

Design colloidal particle morphology and self-assembly for coating applications

DOE PAGES

Jiang, Shan; Van Dyk, Antony; Maurice, Alvin; ...

2017-05-04

The progressive replacement of organic solvent-based coatings by waterborne latex polymer coatings has substantially renovated the coating industry, and generated huge environmental and health benefits. Today, on top of the continuing demand for higher performance and lower costs, the coating industry faces tighter regulation and higher sustainability standards. In addition, the new waterborne coatings have created unique opportunities and challenges in terms of fundamental understanding and research development. To address these challenges, polymer latex binders with diverse particle morphologies have been developed to improve coating performance. Furthermore, colloidal self-assembly has been utilized to help manufacturers make better paint with lessmore » cost. In this report, we review the recent progress in both fundamental study and industrial application in the context of developing new generation architectural coating materials. We introduce the basic concepts in coating materials and showcase several key technologies that have been implemented to improve coating performance. As a result, these technologies also represent the most important considerations in architectural coating design.« less

ASME Material Challenges for Advanced Reactor Concepts

DOE Office of Scientific and Technical Information (OSTI.GOV)

Piyush Sabharwall; Ali Siahpush

2013-07-01

This study presents the material Challenges associated with Advanced Reactor Concept (ARC) such as the Advanced High Temperature Reactor (AHTR). ACR are the next generation concepts focusing on power production and providing thermal energy for industrial applications. The efficient transfer of energy for industrial applications depends on the ability to incorporate cost-effective heat exchangers between the nuclear heat transport system and industrial process heat transport system. The heat exchanger required for AHTR is subjected to a unique set of conditions that bring with them several design challenges not encountered in standard heat exchangers. The corrosive molten salts, especially at highermore » temperatures, require materials throughout the system to avoid corrosion, and adverse high-temperature effects such as creep. Given the very high steam generator pressure of the supercritical steam cycle, it is anticipated that water tube and molten salt shell steam generators heat exchanger will be used. In this paper, the ASME Section III and the American Society of Mechanical Engineers (ASME) Section VIII requirements (acceptance criteria) are discussed. Also, the ASME material acceptance criteria (ASME Section II, Part D) for high temperature environment are presented. Finally, lack of ASME acceptance criteria for thermal design and analysis are discussed.« less

The McMaster Optimal Aging Portal: Usability Evaluation of a Unique Evidence-Based Health Information Website.

PubMed

Barbara, Angela M; Dobbins, Maureen; Haynes, R Brian; Iorio, Alfonso; Lavis, John N; Raina, Parminder; Levinson, Anthony J

2016-05-11

Increasingly, older adults and their informal caregivers are using the Internet to search for health-related information. There is a proliferation of health information online, but the quality of this information varies, often based on exaggerated or dramatic findings, and not easily comprehended by consumers. The McMaster Optimal Aging Portal (Portal) was developed to provide Internet users with high-quality evidence about aging and address some of these current limitations of health information posted online. The Portal includes content for health professionals coming from three best-in-class resources (MacPLUS, Health Evidence, and Health Systems Evidence) and four types of content specifically prepared for the general public (Evidence Summaries, Web Resource Ratings, Blog Posts, and Twitter messages). Our objectives were to share the findings of the usability evaluation of the Portal with particular focus on the content features for the general public and to inform designers of health information websites and online resources for older adults about key usability themes. Data analysis included task performance during usability testing and qualitative content analyses of both the usability sessions and interviews to identify core themes. A total of 37 participants took part in 33 usability testing sessions and 21 focused interviews. Qualitative analysis revealed common themes regarding the Portal's strengths and challenges to usability. The strengths of the website were related to credibility, applicability, browsing function, design, and accessibility. The usability challenges included reluctance to register, process of registering, searching, terminology, and technical features. The study reinforced the importance of including end users during the development of this unique, dynamic, evidence-based health information website. The feedback was applied to iteratively improve website usability. Our findings can be applied by designers of health-related websites.

The McMaster Optimal Aging Portal: Usability Evaluation of a Unique Evidence-Based Health Information Website

PubMed Central

Dobbins, Maureen; Haynes, R. Brian; Iorio, Alfonso; Lavis, John N; Raina, Parminder

2016-01-01

Background Increasingly, older adults and their informal caregivers are using the Internet to search for health-related information. There is a proliferation of health information online, but the quality of this information varies, often based on exaggerated or dramatic findings, and not easily comprehended by consumers. The McMaster Optimal Aging Portal (Portal) was developed to provide Internet users with high-quality evidence about aging and address some of these current limitations of health information posted online. The Portal includes content for health professionals coming from three best-in-class resources (MacPLUS, Health Evidence, and Health Systems Evidence) and four types of content specifically prepared for the general public (Evidence Summaries, Web Resource Ratings, Blog Posts, and Twitter messages). Objective Our objectives were to share the findings of the usability evaluation of the Portal with particular focus on the content features for the general public and to inform designers of health information websites and online resources for older adults about key usability themes. Methods Data analysis included task performance during usability testing and qualitative content analyses of both the usability sessions and interviews to identify core themes. Results A total of 37 participants took part in 33 usability testing sessions and 21 focused interviews. Qualitative analysis revealed common themes regarding the Portal’s strengths and challenges to usability. The strengths of the website were related to credibility, applicability, browsing function, design, and accessibility. The usability challenges included reluctance to register, process of registering, searching, terminology, and technical features. Conclusions The study reinforced the importance of including end users during the development of this unique, dynamic, evidence-based health information website. The feedback was applied to iteratively improve website usability. Our findings can be applied by designers of health-related websites. PMID:27170443

Materials Genome Initiative

NASA Technical Reports Server (NTRS)

Vickers, John

2015-01-01

The Materials Genome Initiative (MGI) project element is a cross-Center effort that is focused on the integration of computational tools to simulate manufacturing processes and materials behavior. These computational simulations will be utilized to gain understanding of processes and materials behavior to accelerate process development and certification to more efficiently integrate new materials in existing NASA projects and to lead to the design of new materials for improved performance. This NASA effort looks to collaborate with efforts at other government agencies and universities working under the national MGI. MGI plans to develop integrated computational/experimental/ processing methodologies for accelerating discovery and insertion of materials to satisfy NASA's unique mission demands. The challenges include validated design tools that incorporate materials properties, processes, and design requirements; and materials process control to rapidly mature emerging manufacturing methods and develop certified manufacturing processes

The Advanced Technology Solar Telescope mount assembly

NASA Astrophysics Data System (ADS)

Warner, Mark; Cho, Myung; Goodrich, Bret; Hansen, Eric; Hubbard, Rob; Lee, Joon Pyo; Wagner, Jeremy

2006-06-01

When constructed on the summit of Haleakala on the island of Maui, Hawaii, the Advanced Technology Solar Telescope (ATST) will be the world's largest solar telescope. The ATST is a unique design that utilizes a state-of-the-art off-axis Gregorian optical layout with five reflecting mirrors delivering light to a Nasmyth instrument rotator, and nine reflecting mirrors delivering light to an instrument suite located on a large diameter rotating coude lab. The design of the telescope mount structure, which supports and positions the mirrors and scientific instruments, has presented noteworthy challenges to the ATST engineering staff. Several novel design solutions, as well as adaptations of existing telescope technologies to the ATST application, are presented in this paper. Also shown are plans for the control system and drives of the structure.

Opto-mechanical design of ShaneAO: the adaptive optics system for the 3-meter Shane Telescope

NASA Astrophysics Data System (ADS)

Ratliff, C.; Cabak, J.; Gavel, D.; Kupke, R.; Dillon, D.; Gates, E.; Deich, W.; Ward, J.; Cowley, D.; Pfister, T.; Saylor, M.

2014-07-01

A Cassegrain mounted adaptive optics instrument presents unique challenges for opto-mechanical design. The flexure and temperature tolerances for stability are tighter than those of seeing limited instruments. This criteria requires particular attention to material properties and mounting techniques. This paper addresses the mechanical designs developed to meet the optical functional requirements. One of the key considerations was to have gravitational deformations, which vary with telescope orientation, stay within the optical error budget, or ensure that we can compensate with a steering mirror by maintaining predictable elastic behavior. Here we look at several cases where deformation is predicted with finite element analysis and Hertzian deformation analysis and also tested. Techniques used to address thermal deformation compensation without the use of low CTE materials will also be discussed.

Reusable Solid Rocket Motor - Accomplishment, Lessons, and a Culture of Success

NASA Technical Reports Server (NTRS)

Moore, D. R.; Phelps, W. J.

2011-01-01

The Reusable Solid Rocket Motor (RSRM) represents the largest solid rocket motor (SRM) ever flown and the only human-rated solid motor. High reliability of the RSRM has been the result of challenges addressed and lessons learned. Advancements have resulted by applying attention to process control, testing, and postflight through timely and thorough communication in dealing with all issues. A structured and disciplined approach was taken to identify and disposition all concerns. Careful consideration and application of alternate opinions was embraced. Focus was placed on process control, ground test programs, and postflight assessment. Process control is mandatory for an SRM, because an acceptance test of the delivered product is not feasible. The RSRM maintained both full-scale and subscale test articles, which enabled continuous improvement of design and evaluation of process control and material behavior. Additionally RSRM reliability was achieved through attention to detail in post flight assessment to observe any shift in performance. The postflight analysis and inspections provided invaluable reliability data as it enables observation of actual flight performance, most of which would not be available if the motors were not recovered. RSRM reusability offered unique opportunities to learn about the hardware. NASA is moving forward with the Space Launch System that incorporates propulsion systems that takes advantage of the heritage Shuttle and Ares solid motor programs. These unique challenges, features of the RSRM, materials and manufacturing issues, and design improvements will be discussed in the paper.

Mars Atmosphere and Volatile Evolution (MAVEN) Mission Design

NASA Technical Reports Server (NTRS)

Folta, David C.

2010-01-01

The Mars Atmosphere and Volatile EvolutioN (MAVEN) mission was selected as the second in the low-cost Mars Scout mission series. MAVEN will determine the role that loss of volatiles to space has played through time from a highly inclined elliptical orbit. The launch period opens November 18. 2013 with arrival September 16, 2014. After achieving a 35-hour capture orbit, maneuvers will reduce the period to 4.5-hours with periapsis near 150 kilometers and maintain the periapsis within a specified density corridor. MAVEN will also execute "Deep Dip" campaigns, with periapsis at an altitude near 125 kilometers. This paper presents the unique mission design challenges of the MAVEN mission.

Human Factors Engineering and testing for a wearable, long duration ultrasound system self-applied by an end user.

PubMed

Taggart, Rebecca; Langer, Matthew D; Lewis, George K

2014-01-01

One of the major challenges in the design of a new class of medical device is ensuring that the device will have a safe and effective user interface for the intended users. Human Factors Engineering addresses these concerns through direct study of how a user interacts with newly designed devices with unique features. In this study, a novel long duration, low intensity therapeutic ultrasound device is tested by 20 end users representative of the intended user population. Over 90% of users were able to operate the device successfully. The therapeutic ultrasound device was found to be reasonably safe and effective for the intended users, uses, and use environments.

Statistical Considerations of Food Allergy Prevention Studies.

PubMed

Bahnson, Henry T; du Toit, George; Lack, Gideon

Clinical studies to prevent the development of food allergy have recently helped reshape public policy recommendations on the early introduction of allergenic foods. These trials are also prompting new research, and it is therefore important to address the unique design and analysis challenges of prevention trials. We highlight statistical concepts and give recommendations that clinical researchers may wish to adopt when designing future study protocols and analysis plans for prevention studies. Topics include selecting a study sample, addressing internal and external validity, improving statistical power, choosing alpha and beta, analysis innovations to address dilution effects, and analysis methods to deal with poor compliance, dropout, and missing data. Copyright © 2017 The Authors. Published by Elsevier Inc. All rights reserved.

Informed consent for clinical trials of deep brain stimulation in psychiatric disease: challenges and implications for trial design.

PubMed

Lipsman, Nir; Giacobbe, Peter; Bernstein, Mark; Lozano, Andres M

2012-02-01

Advances in neuromodulation and an improved understanding of the anatomy and circuitry of psychopathology have led to a resurgence of interest in surgery for psychiatric disease. Clinical trials exploring deep brain stimulation (DBS), a focally targeted, adjustable and reversible form of neurosurgery, are being developed to address the use of this technology in highly selected patient populations. Psychiatric patients deemed eligible for surgical intervention, such as DBS, typically meet stringent inclusion criteria, including demonstrated severity, chronicity and a failure of conventional therapy. Although a humanitarian device exemption by the US Food and Drug Administration exists for its use in obsessive-compulsive disorder, DBS remains a largely experimental treatment in the psychiatric context, with its use currently limited to clinical trials and investigative studies. The combination of a patient population at the limits of conventional therapy and a novel technology in a new indication poses interesting challenges to the informed consent process as it relates to clinical trial enrollment. These challenges can be divided into those that relate to the patient, their disease and the technology, with each illustrating how traditional conceptualisations of research consent may be inadequate in the surgical psychiatry context. With specific reference to risk analysis, patient autonomy, voluntariness and the duty of the clinician-researcher, this paper will discuss the unique challenges that clinical trials of surgery for refractory psychiatric disease present to the consent process. Recommendations are also made for an ethical approach to clinical trial consent acquisition in this unique patient population.

Proprioceptive Actuation Design for Dynamic Legged locomotion

NASA Astrophysics Data System (ADS)

Kim, Sangbae; Wensing, Patrick; Biomimetic Robotics Lab Team

Designing an actuator system for highly-dynamic legged locomotion exhibited by animals has been one of the grand challenges in robotics research. Conventional actuators designed for manufacturing applications have difficulty satisfying challenging requirements for high-speed locomotion, such as the need for high torque density and the ability to manage dynamic physical interactions. It is critical to introduce a new actuator design paradigm and provide guidelines for its incorporation in future mobile robots for research and industry. To this end, we suggest a paradigm called proprioceptive actuation, which enables highly- dynamic operation in legged machines. Proprioceptive actuation uses collocated force control at the joints to effectively control contact interactions at the feet under dynamic conditions. In the realm of legged machines, this paradigm provides a unique combination of high torque density, high-bandwidth force control, and the ability to mitigate impacts through backdrivability. Results show that the proposed design provides an impact mitigation factor that is comparable to other quadruped designs with series springs to handle impact. The paradigm is shown to enable the MIT Cheetah to manage the application of contact forces during dynamic bounding, with results given down to contact times of 85ms and peak forces over 450N. As a result, the MIT Cheetah achieves high-speed 3D running up to 13mph and jumping over an 18-inch high obstacle. The project is sponsored by DARPA M3 program.

Double Dutch: A Tool for Designing Combinatorial Libraries of Biological Systems.

PubMed

Roehner, Nicholas; Young, Eric M; Voigt, Christopher A; Gordon, D Benjamin; Densmore, Douglas

2016-06-17

Recently, semirational approaches that rely on combinatorial assembly of characterized DNA components have been used to engineer biosynthetic pathways. In practice, however, it is not practical to assemble and test millions of pathway variants in order to elucidate how different DNA components affect the behavior of a pathway. To address this challenge, we apply a rigorous mathematical approach known as design of experiments (DOE) that can be used to construct empirical models of system behavior without testing all variants. To support this approach, we have developed a tool named Double Dutch, which uses a formal grammar and heuristic algorithms to automate the process of DOE library design. Compared to designing by hand, Double Dutch enables users to more efficiently and scalably design libraries of pathway variants that can be used in a DOE framework and uniquely provides a means to flexibly balance design considerations of statistical analysis, construction cost, and risk of homologous recombination, thereby demonstrating the utility of automating decision making when faced with complex design trade-offs.

Stitch overlap via coloring technique enables maskless via

NASA Astrophysics Data System (ADS)

Civay, D.; Laffosse, E.

2017-03-01

Lithographic patterning limits can be a cost-barrier that delays advancement to new nodes. This paper introduces a cost-saving design method that enables a maskless via. Multi-patterning or coloring of a design is a technique that is used at advanced nodes to aid in patterning. Coloring allows designers to designate different patterns on one level to be printed with different masks. Stitch overlap via (SOV) is a coloring technique introduced herein. SOV utilizes via-aware coloring and a unique process flow to print a maskless via. Identification of qualifying design structures is achieved through a custom program. The program inputs the design level of the multipatterned layer and the via levels above and below to determine the coloring decomposition. Vias are a particularly challenging layer to print due to the dimensions required for these pillars. SOV is a methodology for identifying qualifying multi-patterned layouts and replacing them with a new design that enables a maskless via layer.

Toward Perovskite Solar Cell Commercialization: A Perspective and Research Roadmap Based on Interfacial Engineering.

PubMed

Rajagopal, Adharsh; Yao, Kai; Jen, Alex K-Y

2018-06-08

High-efficiency and low-cost perovskite solar cells (PVKSCs) are an ideal candidate for addressing the scalability challenge of solar-based renewable energy. The dynamically evolving research field of PVKSCs has made immense progress in solving inherent challenges and capitalizing on their unique structure-property-processing-performance traits. This review offers a unique outlook on the paths toward commercialization of PVKSCs from the interfacial engineering perspective, relevant to both specialists and nonspecialists in the field through a brief introduction of the background of the field, current state-of-the-art evolution, and future research prospects. The multifaceted role of interfaces in facilitating PVKSC development is explained. Beneficial impacts of diverse charge-transporting materials and interfacial modifications are summarized. In addition, the role of interfaces in improving efficiency and stability for all emerging areas of PVKSC design are also evaluated. The authors' integral contributions in this area are highlighted on all fronts. Finally, future research opportunities for interfacial material development and applications along with scalability-durability-sustainability considerations pivotal for facilitating laboratory to industry translation are presented. © 2018 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

Regioselective Reactions for Programmable Resveratrol Oligomer Synthesis

PubMed Central

Snyder, Scott A.; Gollner, Andreas; Chiriac, Maria I.

2011-01-01

Although much attention has been devoted to resveratrol, a unique polyphenol produced by plants throughout the world and credited as potentially being responsible for the so-called “French paradox” given its broad spectrum activity, the hundreds of oligomeric materials derived from it have been largely ignored despite their similarly high biochemical potential. Challenges in achieving their isolation in quantity from natural sources, coupled with an inability to rationally prepare them in the laboratory, are the main culprits. Here we show that a programmable, controlled, and potentially scaleable synthesis of the resveratrol family is possible through a unique three-stage design. These efforts required novel tactics coupled with strategy- and reagent-guided functionalizations to differentiate two distinct cores possessing multiple sites with the same and/or similar reactivity, ultimately leading to five higher-order natural products. We anticipate that this work 1) demonstrates that challenging, positionally-selective functionalizations of complex materials are possible where biosynthetic studies have indicated otherwise, 2) provides materials and tools to finally unlock the full biochemical potential of the family, particularly from the standpoint of activity and drug-property optimization, and 3) affords an intellectual framework to potentially access other oligomeric families controllably. PMID:21697944

Bridging the Gap Between Research and Practice: Implementation Science.

PubMed

Olswang, Lesley B; Prelock, Patricia A

2015-12-01

This article introduces implementation science, which focuses on research methods that promote the systematic application of research findings to practice. The narrative defines implementation science and highlights the importance of moving research along the pipeline from basic science to practice as one way to facilitate evidence-based service delivery. This review identifies challenges in developing and testing interventions in order to achieve widespread adoption in practice settings. A framework for conceptualizing implementation research is provided, including an example to illustrate the application of principles in speech-language pathology. Last, the authors reflect on the status of implementation research in the discipline of communication sciences and disorders. The extant literature highlights the value of implementation science for reducing the gap between research and practice in our discipline. While having unique principles guiding implementation research, many of the challenges and questions are similar to those facing any investigators who are attempting to design valid and reliable studies. This article is intended to invigorate interest in the uniqueness of implementation science among those pursuing both basic and applied research. In this way, it should help ensure the discipline's knowledge base is realized in practice and policy that affects the lives of individuals with communication disorders.

Innovative pharmaceutical development based on unique properties of nanoscale delivery formulation

PubMed Central

Mozhi, Anbu; Zhang, Xu; Zhao, Yuanyuan; Xue, Xiangdong; Hao, Yanli; Zhang, Xiaoning; Wang, Paul C.; Liang, Xing-Jie

2014-01-01

The advent of nanotechnology has reignited interest in the field of pharmaceutical science for the development of nanomedicine. Nanomedicinal formulations are nanometer-sized carrier materials designed for increasing the drug tissue bioavailability, thereby improving the treatment of systemically applied chemotherapeutic drugs. Nanomedicine is a new approach to deliver the pharmaceuticals through different routes of administration with safer and more effective therapies compared to conventional methods. To date, various kinds of nanomaterials have been developed over the years to make delivery systems more effective for the treatment of various diseases. Even though nanomaterials have significant advantages due to their unique nanoscale properties, there are still significant challenges in the improvement and development of nanoformulations with composites and other materials. Here in this review, we highlight the nanomedicinal formulations aiming to improve the balance between the efficacy and the toxicity of therapeutic interventions through different routes of administration and how to design nanomedicine for safer and more effective ways to improve the treatment quality. We also emphasize the environmental and health prospects of nanomaterials for human health care. PMID:23860639

Unique Chernobyl Cranes for Deconstruction Activities in the New Safe Confinement - 13542

DOE Office of Scientific and Technical Information (OSTI.GOV)

Parameswaran, N.A. Vijay; Chornyy, Igor; Owen, Rob

2013-07-01

The devastation left behind from the Chernobyl nuclear power plant (ChNPP) Unit 4 accident which occurred on April 26, 1986 presented unparalleled technical challenges to the world engineering and scientific community. One of the largest tasks that are in progress is the design and construction of the New Safe Confinement (NSC). The NSC is an engineered enclosure for the entire object shelter (OS) that includes a suite of process equipment. The process equipment will be used for the dismantling of the destroyed Chernobyl Nuclear Power Plant (ChNPP) Unit. One of the major mechanical handling systems to be installed in themore » NSC is the Main Cranes System (MCS). The planned decontamination and decommissioning or dismantling (D and D) activities will require the handling of heavily shielded waste disposal casks containing nuclear fuel as well as lifting and transporting extremely large structural elements. These activities, to be performed within the NSC, will require large and sophisticated cranes. The article will focus on the unique design features of the MCS for the D and D activities. (authors)« less

Innovative pharmaceutical development based on unique properties of nanoscale delivery formulation

NASA Astrophysics Data System (ADS)

Kumar, Anil; Chen, Fei; Mozhi, Anbu; Zhang, Xu; Zhao, Yuanyuan; Xue, Xiangdong; Hao, Yanli; Zhang, Xiaoning; Wang, Paul C.; Liang, Xing-Jie

2013-08-01

The advent of nanotechnology has reignited interest in the field of pharmaceutical science for the development of nanomedicine. Nanomedicinal formulations are nanometer-sized carrier materials designed for increasing the drug tissue bioavailability, thereby improving the treatment of systemically applied chemotherapeutic drugs. Nanomedicine is a new approach to deliver the pharmaceuticals through different routes of administration with safer and more effective therapies compared to conventional methods. To date, various kinds of nanomaterials have been developed over the years to make delivery systems more effective for the treatment of various diseases. Even though nanomaterials have significant advantages due to their unique nanoscale properties, there are still significant challenges in the improvement and development of nanoformulations with composites and other materials. Here in this review, we highlight the nanomedicinal formulations aiming to improve the balance between the efficacy and the toxicity of therapeutic interventions through different routes of administration and how to design nanomedicine for safer and more effective ways to improve the treatment quality. We also emphasize the environmental and health prospects of nanomaterials for human health care.

Ketide Synthase (KS) Domain Prediction and Analysis of Iterative Type II PKS Gene in Marine Sponge-Associated Actinobacteria Producing Biosurfactants and Antimicrobial Agents

PubMed Central

Selvin, Joseph; Sathiyanarayanan, Ganesan; Lipton, Anuj N.; Al-Dhabi, Naif Abdullah; Valan Arasu, Mariadhas; Kiran, George S.

2016-01-01

The important biological macromolecules, such as lipopeptide and glycolipid biosurfactant producing marine actinobacteria were analyzed and their potential linkage between type II polyketide synthase (PKS) genes was explored. A unique feature of type II PKS genes is their high amino acid (AA) sequence homology and conserved gene organization. These enzymes mediate the biosynthesis of polyketide natural products with enormous structural complexity and chemical nature by combinatorial use of various domains. Therefore, deciphering the order of AA sequence encoded by PKS domains tailored the chemical structure of polyketide analogs still remains a great challenge. The present work deals with an in vitro and in silico analysis of PKS type II genes from five actinobacterial species to correlate KS domain architecture and structural features. Our present analysis reveals the unique protein domain organization of iterative type II PKS and KS domain of marine actinobacteria. The findings of this study would have implications in metabolic pathway reconstruction and design of semi-synthetic genomes to achieve rational design of novel natural products. PMID:26903957

Correlative Microscopy of Neutron-Irradiated Materials

DOE PAGES

Briggs, Samuel A.; Sridharan, Kumar; Field, Kevin G.

2016-12-31

A nuclear reactor core is a highly demanding environment that presents several unique challenges for materials performance. Materials in modern light water reactor (LWR) cores must survive several decades in high-temperature (300-350°C) aqueous corrosion conditions while being subject to large amounts of high-energy neutron irradiation. Next-generation reactor designs seek to use more corrosive coolants (e.g., molten salts) and even greater temperatures and neutron doses. The high amounts of disorder and unique crystallographic defects and microchemical segregation effects induced by radiation inevitably lead to property degradation of materials. Thus, maintaining structural integrity and safety margins over the course of the reactor'smore » service life thus necessitates the ability to understand and predict these degradation phenomena in order to develop new, radiation-tolerant materials that can maintain the required performance in these extreme conditions.« less

Applications of mixed-methods methodology in clinical pharmacy research.

PubMed

Hadi, Muhammad Abdul; Closs, S José

2016-06-01

Introduction Mixed-methods methodology, as the name suggests refers to mixing of elements of both qualitative and quantitative methodologies in a single study. In the past decade, mixed-methods methodology has gained popularity among healthcare researchers as it promises to bring together the strengths of both qualitative and quantitative approaches. Methodology A number of mixed-methods designs are available in the literature and the four most commonly used designs in healthcare research are: the convergent parallel design, the embedded design, the exploratory design, and the explanatory design. Each has its own unique advantages, challenges and procedures and selection of a particular design should be guided by the research question. Guidance on designing, conducting and reporting mixed-methods research is available in the literature, so it is advisable to adhere to this to ensure methodological rigour. When to use it is best suited when the research questions require: triangulating findings from different methodologies to explain a single phenomenon; clarifying the results of one method using another method; informing the design of one method based on the findings of another method, development of a scale/questionnaire and answering different research questions within a single study. Two case studies have been presented to illustrate possible applications of mixed-methods methodology. Limitations Possessing the necessary knowledge and skills to undertake qualitative and quantitative data collection, analysis, interpretation and integration remains the biggest challenge for researchers conducting mixed-methods studies. Sequential study designs are often time consuming, being in two (or more) phases whereas concurrent study designs may require more than one data collector to collect both qualitative and quantitative data at the same time.

Development of Design Rules for Reliable Antisense RNA Behavior in E. coli.

PubMed

Hoynes-O'Connor, Allison; Moon, Tae Seok

2016-12-16

A key driver of synthetic biology is the development of designable genetic parts with predictable behaviors that can be quickly implemented in complex genetic systems. However, the intrinsic complexity of gene regulation can make the rational design of genetic parts challenging. This challenge is apparent in the design of antisense RNA (asRNA) regulators. Though asRNAs are well-known regulators, the literature governing their design is conflicting and leaves the synthetic biology community without clear asRNA design rules. The goal of this study is to perform a comprehensive experimental characterization and statistical analysis of 121 unique asRNA regulators in order to resolve the conflicts that currently exist in the literature. asRNAs usually consist of two regions, the Hfq binding site and the target binding region (TBR). First, the behaviors of several high-performing Hfq binding sites were compared, in terms of their ability to improve repression efficiencies and their orthogonality. Next, a large-scale analysis of TBR design parameters identified asRNA length, the thermodynamics of asRNA-mRNA complex formation, and the percent of target mismatch as key parameters for TBR design. These parameters were used to develop simple asRNA design rules. Finally, these design rules were applied to construct both a simple and a complex genetic circuit containing different asRNAs, and predictable behavior was observed in both circuits. The results presented in this study will drive synthetic biology forward by providing useful design guidelines for the construction of asRNA regulators with predictable behaviors.

Overview of NASA's Thermal Control System Development for Exploration Project

NASA Technical Reports Server (NTRS)

Stephan, Ryan A.

2011-01-01

The now-cancelled Constellation Program included the Orion, Altair, and Lunar Surface Systems project offices. The first two elements, Orion and Altair, were planned to be manned space vehicles while the third element was much more diverse and included several sub-elements. Among other things, these sub-elements were Rovers and a Lunar Habitat. The planned missions involving these systems and vehicles included several risks and design challenges. Due to the unique thermal operating environment, many of these risks and challenges were associated with the vehicles thermal control system. NASA s Exploration Technology Development Program (ETDP) consisted of various technology development projects. The project chartered with mitigating the aforementioned thermal risks and design challenges was the Thermal Control System Development for Exploration Project. These risks and design challenges were being addressed through a rigorous technology development process that was planned to culminate with an integrated thermal control system test. Although the technologies being developed were originally aimed towards mitigating specific Constellation risks, the technology development process is being continued within a new program. This continued effort is justified by the fact that many of the technologies are generically applicable to future spacecraft thermal control systems. The current paper summarizes the development efforts being performed by the technology development project. The development efforts involve heat acquisition and heat rejection hardware including radiators, heat exchangers, and evaporators. The project has also been developing advanced phase change material heat sinks and performing a material compatibility assessment for a promising thermal control system working fluid. The to-date progress and lessons-learned from these development efforts will be discussed throughout the paper.

YogaHome: teaching and research challenges in a yoga program with homeless adults.

PubMed

Davis-Berman, Jennifer; Farkas, Jean

2012-01-01

YogaHome is a therapeutic yoga program for homeless women. Developing and refining YogaHome provided a unique opportunity to explore the process of teaching yoga to women faced with the physical and emotional stress of living in a homeless shelter. Unique teaching and research challenges are presented and recommendations for future programs are discussed.

Curation, Spacecraft Recovery and Preliminary Examination for the Stardust Mission: A Perspective from the Curatorial Facility

NASA Technical Reports Server (NTRS)

Zolensky, Michael; Nakamura-Messenger, Keiko; Fletcher, Lisa; See, Thomas

2008-01-01

We briefly describe some of the challenges to the Stardust mission, curation and sample preliminary analysis, from the perspective of the Curation Office at the Johnson Space Center. Our goal is to inform persons planning future sample returns, so that they may learn from both our successes and challenges (and avoid some of our mistakes). The Curation office played a role in the mission from its inception, most critically assisting in the design and implementation of the spacecraft contamination control plan, and in planning and documenting the recovery of the spacecraft reentry capsule in Utah. A unique class 100 cleanroom was built to maintain the returned comet and interstellar samples in clean comfort, and to permit dissection and allocation of samples for analysis.

Modular projects and 'mean questions': best practices for advising an International Genetically Engineered Machines team.

PubMed

Tsui, Jennifer; Meyer, Anne S

2016-07-01

In the yearly Internationally Genetically Engineered Machines (iGEM) competition, teams of Bachelor's and Master's students design and build an engineered biological system using DNA technologies. Advising an iGEM team poses unique challenges due to the inherent difficulties of mounting and completing a new biological project from scratch over the course of a single academic year; the challenges in obtaining financial and structural resources for a project that will likely not be fully realized; and conflicts between educational and competition-based goals. This article shares tips and best practices for iGEM team advisors, from two team advisors with very different experiences with the iGEM competition. © FEMS 2016. All rights reserved. For permissions, please e-mail: journals.permissions@oup.com.

Prospects of application of additive technologies for increasing the efficiency of impeller machines

NASA Astrophysics Data System (ADS)

Belova, O. V.; Borisov, Yu. A.

2017-08-01

Impeller machine is a device in which the flow path carries out the supply (or retraction) of mechanical energy to the flow of a working fluid passing through the machine. To increase the efficiency of impeller machines, it is necessary to use design modern technologies, namely the use of numerical methods for conducting research in the field of gas dynamics, as well as additive manufacturing (AM) for the of both prototypes and production model. AM technologies are deservedly rightly called revolutionary because they give unique possibility for manufacturing products, creating perfect forms, both light and durable. The designers face the challenge of developing a new design methodology, since AM allows the use of the concept of "Complexity For Free". The "Complexity For Free" conception is based on: complexity of the form; hierarchical complexity; complexity of the material; functional complexity. The new technical items design method according to a functional principle is also investigated.

Power system design of ESMO

NASA Astrophysics Data System (ADS)

Ulrich, Steve; Veilleux, Jean-François; Landry Corbin, François

2009-01-01

The European Student Moon Orbiter (ESMO) spacecraft is a student-built mini satellite being designed for a mission to the Moon. Designing and launching mini satellites are becoming a current trend in the space sector since they provide an economic way to perform innovative scientific experiments and in-flight demonstration of novel space technologies. The generation, storage, control, and distribution of the electrical power in a mini satellite represents unique challenges to the power engineer since the mass and volume restrictions are very stringent. Regardless of these problems, every subsystem and payload equipment must be operated within their specified voltage band whenever they required to be turned on. This paper presents the preliminary design of a lightweight, compact, and reliable power system for ESMO that can generate 720 W. Some of the key components of the EPS include ultra triple-junction (UTJ) GaAs solar cells controlled by maximum power point trackers, and high efficiency Li-ion secondary batteries recharged in parallel.

X-57 Power and Command System Design

NASA Technical Reports Server (NTRS)

Clarke, Sean; Redifer, Matthew; Papathakis, Kurt; Samuel, Aamod; Foster, Trevor

2017-01-01

This paper describes the power and command system architecture of the X-57 Maxwell flight demonstrator aircraft. The X-57 is an experimental aircraft designed to demonstrate radically improved aircraft efficiency with a 3.5 times aero-propulsive efficiency gain at a "high-speed cruise" flight condition for comparable general aviation aircraft. These gains are enabled by integrating the design of a new, optimized wing and a new electric propulsion system. As a result, the X-57 vehicle takes advantage of the new capabilities afforded by electric motors as primary propulsors. Integrating new technologies into critical systems in experimental aircraft poses unique challenges that require careful design considerations across the entire vehicle system, such as qualification of new propulsors (motors, in the case of the X-57 aircraft), compatibility of existing systems with a new electric power distribution bus, and instrumentation and monitoring of newly qualified propulsion system devices.

Yield enhancement of 3D flash devices through broadband brightfield inspection of the channel hole process module

NASA Astrophysics Data System (ADS)

Lee, Jung-Youl; Seo, Il-Seok; Ma, Seong-Min; Kim, Hyeon-Soo; Kim, Jin-Woong; Kim, DoOh; Cross, Andrew

2013-03-01

The migration to a 3D implementation for NAND flash devices is seen as the leading contender to replace traditional planar NAND architectures. However the strategy of replacing shrinking design rules with greater aspect ratios is not without its own set of challenges. The yield-limiting defect challenges for the planar NAND front end were primarily bridges, protrusions and residues at the bottom of the gates, while the primary challenges for front end 3D NAND is buried particles, voids and bridges in the top, middle and bottom of high aspect ratio structures. Of particular interest are the yield challenges in the channel hole process module and developing an understanding of the contribution of litho and etch defectivity for this challenging new integration scheme. The key defectivity and process challenges in this module are missing, misshapen channel holes or under-etched channel holes as well as reducing noise sources related to other none yield limiting defect types and noise related to the process integration scheme. These challenges are expected to amplify as the memory density increases. In this study we show that a broadband brightfield approach to defect monitoring can be uniquely effective for the channel hole module. This approach is correlated to end-of-line (EOL) Wafer Bin Map for verification of capability.

Brain Metastasis: Unique Challenges and Open Opportunities

PubMed Central

Lowery, Frank J.; Yu, Dihua

2016-01-01

The metastasis of cancer to the central nervous system (CNS) remains a devastating clinical reality, carrying an estimated survival time of less than one year in spite of recent therapeutic breakthroughs for other disease contexts. Advances in brain metastasis research are hindered by a number of reasons, including its complicated nature and the difficulty of modeling metastatic cancer growth in the unique brain microenvironment. In this review, we will discuss the clinical challenge, and compare the values and limitations of the available models for brain metastasis research. Additionally, we will specifically address current knowledge on how brain metastases take advantage of the unique brain environment to benefit their own growth. Finally, we will explore the distinctive metabolic and nutrient characteristics of the brain; how these paradoxically represent barriers to establishment of brain metastasis, but also provide ample supplies for metastatic cells’ growth in the brain. We envision that multi-disciplinary innovative approaches will open opportunities for the field to make breakthroughs in tackling unique challenges of brain metastasis. PMID:27939792

Nanostructured materials for advanced energy conversion and storage devices

NASA Astrophysics Data System (ADS)

Aricò, Antonino Salvatore; Bruce, Peter; Scrosati, Bruno; Tarascon, Jean-Marie; van Schalkwijk, Walter

2005-05-01

New materials hold the key to fundamental advances in energy conversion and storage, both of which are vital in order to meet the challenge of global warming and the finite nature of fossil fuels. Nanomaterials in particular offer unique properties or combinations of properties as electrodes and electrolytes in a range of energy devices. This review describes some recent developments in the discovery of nanoelectrolytes and nanoelectrodes for lithium batteries, fuel cells and supercapacitors. The advantages and disadvantages of the nanoscale in materials design for such devices are highlighted.

Managing residual limb hyperhidrosis in wounded warriors.

PubMed

Pace, Sarah; Kentosh, Joshua

2016-06-01

Residual limb dermatologic problems are a common concern among young active traumatic amputee patients who strive to maintain an active lifestyle. Hyperhidrosis of residual limbs is a recognized inciting factor that often contributes to residual limb dermatoses and is driven by the design of the prosthetic liner covering the residual limb. Treatment of hyperhidrosis in this population presents a unique challenge. Several accepted treatments of hyperhidrosis can offer some relief but have been limited by lack of results or side-effect profiles. Microwave thermal ablation has presented an enticing potential for residual limb hyperhidrosis.

Ethical issues in neonatal and pediatric clinical trials.

PubMed

Laventhal, Naomi; Tarini, Beth A; Lantos, John

2012-10-01

Children have been identified as uniquely vulnerable clinical research subjects since the early 1970s. This article reviews the historical underpinnings of this designation, the current regulatory framework for pediatric and neonatal research, and common problems in pediatric research oversight. It also presents 3 areas of pediatric and neonatal research (genomic screening, healthy children donating stem cells, and therapeutic hypothermia for neonates with hypoxic-ischemic encephalopathy) that highlight contemporary challenges in pediatric research ethics, including balancing risk and benefit, informed consent and assent, and clinical equipoise. Copyright © 2012 Elsevier Inc. All rights reserved.

But is it science?

PubMed Central

Watts, Mike; Salehjee, Saima; Essex, Jane

2017-01-01

ABSTRACT Early years science education is not science, but a curricular construction designed to induct young children into a range of ideas and practices related to the natural world. While inquiry-based learning is an important approach to this, it is not of itself unique to science and there are a range of logico-mathematical constructions that come closer to the essence of science. In this paper we discuss just three: empirical question-asking, transgressive play, and good thinking. The challenge, of course is to induct early years practitioners to a different way of shaping early science. PMID:28392619

Alpbach Summer School - a unique learning experience

NASA Astrophysics Data System (ADS)

Kern, K.; Aulinas, J.; Clifford, D.; Krejci, D.; Topham, R.

2011-12-01

The Alpbach Summer School is a ten-day program that provides a unique opportunity for young european science and engineering students, both undergraduate and graduate, to learn how to approach the entire design process of a space mission. The theme of the 2010 Summer School was "New Space Missions to Understand Climate Change", a current, challenging, very broad and complex topic. The program was established more than 35 years ago and is organised in two interrelated parts: a series of lectures held by renowned experts in the field (in the case of this specific year, climate change and space engineering experts) that provides a technical and scientific background for the workshops that follow, the core of the Summer School. For the workshops the students are split into four international, interdisciplinary teams of about 15 students. In 2010 every team had to complete a number of tasks, four in total: (1) identify climate change research gaps and design a space mission that has not yet been flown or proposed, (2) define the science objectives and requirements of the mission, (3) design a spacecraft that meets the mission requirements, which includes spacecraft design and construction, payload definition, orbit calculations, but also the satellite launch, operation and mission costs and (4) write up a short mission proposal and present the results to an expert review panel. Achieving these tasks in only a few days in a multicultural, interdisciplinary team represents a major challenge for all participants and provides an excellent practical learning experience. Over the course of the program, students do not just learn facts about climate change and space engineering, but scientists also learn from engineers and engineers from scientists. The participants have to deepen their knowledge in an often unfamiliar field, develop organisational and team-work skills and work under pressure. Moreover, teams are supported by team and roving tutors and get the opportunity to meet and learn from international experts. This presentation will provide an overview of the Alpbach Summer School program from a student's perspective. The different stages of this unique and enriching experience will be covered. Special attention will be paid to the workshops, which, as mentioned above, are the core of the Alpbach Summer School. During these intense workshops, participants work towards the proposed goals resulting in the design proposal of a space mission. The Alpbach Summer School is organised by FFG and co-sponsored by ESA, ISSI and the national space authorities of ESA member and cooperating states.

SVAS3: Strain Vector Aided Sensorization of Soft Structures

PubMed Central

Culha, Utku; Nurzaman, Surya G.; Clemens, Frank; Iida, Fumiya

2014-01-01

Soft material structures exhibit high deformability and conformability which can be useful for many engineering applications such as robots adapting to unstructured and dynamic environments. However, the fact that they have almost infinite degrees of freedom challenges conventional sensory systems and sensorization approaches due to the difficulties in adapting to soft structure deformations. In this paper, we address this challenge by proposing a novel method which designs flexible sensor morphologies to sense soft material deformations by using a functional material called conductive thermoplastic elastomer (CTPE). This model-based design method, called Strain Vector Aided Sensorization of Soft Structures (SVAS3), provides a simulation platform which analyzes soft body deformations and automatically finds suitable locations for CTPE-based strain gauge sensors to gather strain information which best characterizes the deformation. Our chosen sensor material CTPE exhibits a set of unique behaviors in terms of strain length electrical conductivity, elasticity, and shape adaptability, allowing us to flexibly design sensor morphology that can best capture strain distributions in a given soft structure. We evaluate the performance of our approach by both simulated and real-world experiments and discuss the potential and limitations. PMID:25036332

Development of bioengineering system for stem cell proliferation

NASA Astrophysics Data System (ADS)

Park, H. S.; Shah, R.; Shah, C.

2016-08-01

From last decades, intensive research in the field of stem cells proliferation had been promoted due to the unique property of stem cells to self-renew themselves into multiples and has potential to replicate into an organ or tissues and so it's highly demanding though challenging. Bioreactor, a mechanical device, works as a womb for stem cell proliferation by providing nutritious environment for the proper growth of stem cells. Various factors affecting stem cells growth are the bioreactor mechanism, feeding of continuous nutrients, healthy environment, etc., but it always remains a challenge for controlling biological parameters. The present paper unveils the design of mechanical device commonly known as bioreactor in tissues engineering and biotech field, use for proliferation of stem cells and imparts the proper growing condition for stem cells. This high functional bioreactor provides automation mixing of cell culture and stem cells. This design operates in conjunction with mechanism of reciprocating motion. Compare to commercial bioreactors, this proposed design is more convenient, easy to operate and less maintenance is required as bioreactor culture bag is made of polyethylene which is single use purpose. Development of this bioengineering system will be beneficial for better growth and expansion of stem cell

Strategies and Challenges in Clinical Trials Targeting Human Aging

PubMed Central

Newman, John C.; Milman, Sofiya; Hashmi, Shahrukh K.; Austad, Steve N.; Kirkland, James L.; Halter, Jeffrey B.

2016-01-01

Interventions that target fundamental aging processes have the potential to transform human health and health care. A variety of candidate drugs have emerged from basic and translational research that may target aging processes. Some of these drugs are already in clinical use for other purposes, such as metformin and rapamycin. However, designing clinical trials to test interventions that target the aging process poses a unique set of challenges. This paper summarizes the outcomes of an international meeting co-ordinated by the NIH-funded Geroscience Network to further the goal of developing a translational pipeline to move candidate compounds through clinical trials and ultimately into use. We review the evidence that some drugs already in clinical use may target fundamental aging processes. We discuss the design principles of clinical trials to test such interventions in humans, including study populations, interventions, and outcomes. As examples, we offer several scenarios for potential clinical trials centered on the concepts of health span (delayed multimorbidity and functional decline) and resilience (response to or recovery from an acute health stress). Finally, we describe how this discussion helped inform the design of the proposed Targeting Aging with Metformin study. PMID:27535968

Bringing nanomedicines to market: regulatory challenges, opportunities, and uncertainties.

PubMed

Nijhara, Ruchika; Balakrishnan, Krishna

2006-06-01

Scientists and entrepreneurs who contemplate developing nanomedicine products face several unique challenges in addition to many of the traditional hurdles of product development. In this review we analyze the major physicochemical, biologic and functional characteristics of several nanomedicine products on the market and explore the question of what made them unique. What made them successful? We also focus on the regulatory challenges faced by nanomedicine product developers. Based on these analyses, we propose the factors that are most likely to contribute to the success of nanomedicine products.

Gene therapy in rare diseases: the benefits and challenges of developing a patient-centric registry for Strimvelis in ADA-SCID.

PubMed

Stirnadel-Farrant, Heide; Kudari, Mahesh; Garman, Nadia; Imrie, Jessica; Chopra, Bikramjit; Giannelli, Stefania; Gabaldo, Michela; Corti, Ambra; Zancan, Stefano; Aiuti, Alessandro; Cicalese, Maria Pia; Batta, Rohit; Appleby, Jonathan; Davinelli, Mario; Ng, Pauline

2018-04-06

Strimvelis (autologous CD34+ cells transduced to express adenosine deaminase [ADA]) is the first ex vivo stem cell gene therapy approved by the European Medicines Agency (EMA), indicated as a single treatment for patients with ADA-severe combined immunodeficiency (ADA-SCID) who lack a suitable matched related bone marrow donor. Existing primary immunodeficiency registries are tailored to transplantation outcomes and do not capture the breadth of safety and efficacy endpoints required by the EMA for the long-term monitoring of gene therapies. Furthermore, for extended monitoring of Strimvelis, the young age of children treated, small patient numbers, and broad geographic distribution of patients all increase the risk of loss to follow-up before sufficient data have been collected. Establishing individual investigator sites would be impractical and uneconomical owing to the small number of patients from each location receiving Strimvelis. An observational registry has been established to monitor the safety and effectiveness of Strimvelis in up to 50 patients over a minimum of 15 years. To address the potential challenges highlighted above, data will be collected by a single investigator site at Ospedale San Raffaele (OSR), Milan, Italy, and entered into the registry via a central electronic platform. Patients/families and the patient's local physician will also be able to submit healthcare information directly to the registry using a uniquely designed electronic platform. Data entry will be monitored by a Gene Therapy Registry Centre (funded by GlaxoSmithKline) who will ensure that necessary information is collected and flows between OSR, the patient/family and the patient's local healthcare provider. The Strimvelis registry sets a precedent for the safety monitoring of future gene therapies. A unique, patient-focused design has been implemented to address the challenges of long-term follow-up of patients treated with gene therapy for a rare disease. Strategies to ensure data completeness and patient retention in the registry will help fulfil pharmacovigilance requirements. Collaboration with partners is being sought to expand from a treatment registry into a disease registry. Using practical and cost-efficient approaches, the Strimvelis registry is hoped to encourage further innovation in registry design within orphan drug development.

Self Managing Heart Failure in Remote Australia - Translating Concepts into Clinical Practice

PubMed Central

Iyngkaran, Pupalan; Toukhsati, Samia R.; Harris, Melanie; Connors, Christine; Kangaharan, Nadarajan; Ilton, Marcus; Nagel, Tricia; Moser, Debra K.; Battersby, Malcolm

2016-01-01

Congestive heart failure (CHF) is an ambulatory health care condition characterized by episodes of decompensation and is usually without cure. It is a leading cause for morbidity and mortality and the lead cause for hospital admissions in older patients in the developed world. The long-term requirement for medical care and pharmaceuticals contributes to significant health care costs. CHF management follows a hierarchy from physician prescription to allied health, predominately nurse-led, delivery of care. Health services are easier to access in urban compared to rural settings. The differentials for more specialized services could be even greater. Remote Australia is thus faced with unique challenges in delivering CHF best practice. Chronic disease self-management programs (CDSMP) were designed to increase patient participation in their health and alleviate stress on health systems. There have been CDSMP successes with some diseases, although challenges still exist for CHF. These challenges are amplified in remote Australia due to geographic and demographic factors, increased burden of disease, and higher incidence of comorbidities. In this review we explore CDSMP for CHF and the challenges for our region. PMID:27397492

Designing Epigenome Editors: Considerations of Biochemical and Locus Specificities.

PubMed

Sen, Dilara; Keung, Albert J

2018-01-01

The advent of locus-specific protein recruitment technologies has enabled a new class of studies in chromatin biology. Epigenome editors enable biochemical modifications of chromatin at almost any specific endogenous locus. Their locus specificity unlocks unique information including the functional roles of distinct modifications at specific genomic loci. Given the growing interest in using these tools for biological and translational studies, there are many specific design considerations depending on the scientific question or clinical need. Here we present and discuss important design considerations and challenges regarding the biochemical and locus specificities of epigenome editors. These include how to account for the complex biochemical diversity of chromatin; control for potential interdependency of epigenome editors and their resultant modifications; avoid sequestration effects; quantify the locus specificity of epigenome editors; and improve locus specificity by considering concentration, affinity, avidity, and sequestration effects.

The Penguin: a Low Reynolds Number Powered Glider for Station Keeping Missions

NASA Technical Reports Server (NTRS)

Costello, J. K.; Greene, D. W.; Lee, T. T.; Matier, P. T.; Mccarthy, T. R.; Mcguire, R. J.; Schuette, M. J.

1990-01-01

The Penguin is a low Reynolds number (approx. 100,000) remotely piloted vehicle (RPV). It was designed to fly three laps indoors around two pylons in a figure-eight course while maximizing loiter time. The Penguin's low Reynolds number mission is an important one currently being studied for possible future flights in the atmospheres of other planets and for specialized military missions. Although the Penguin's mission seemed quite simple at first, the challenges of such low Reynolds number flight have proven to be quite unique. In addition to the constraint of low Reynolds number flight, the aircraft had to be robust in its control, highly durable, and it had to carry a small instrument package. The Penguin's flight plan, concept, performance, aerodynamic design, weight estimation, structural design, propulsion, stability and control, and cost estimate is detailed.

Implementation Of Fuzzy Automated Brake Controller Using TSK Algorithm

NASA Astrophysics Data System (ADS)

Mittal, Ruchi; Kaur, Magandeep

2010-11-01

In this paper an application of Fuzzy Logic for Automatic Braking system is proposed. Anti-blocking system (ABS) brake controllers pose unique challenges to the designer: a) For optimal performance, the controller must operate at an unstable equilibrium point, b) Depending on road conditions, the maximum braking torque may vary over a wide range, c) The tire slippage measurement signal, crucial for controller performance, is both highly uncertain and noisy. A digital controller design was chosen which combines a fuzzy logic element and a decision logic network. The controller identifies the current road condition and generates a command braking pressure signal Depending upon the speed and distance of train. This paper describes design criteria, and the decision and rule structure of the control system. The simulation results present the system's performance depending upon the varying speed and distance of the train.

Making products available among community health workers: Evidence for improving community health supply chains from Ethiopia, Malawi, and Rwanda

PubMed Central

Chandani, Yasmin; Andersson, Sarah; Heaton, Alexis; Noel, Megan; Shieshia, Mildred; Mwirotsi, Amanda; Krudwig, Kirstin; Nsona, Humphreys; Felling, Barbara

2014-01-01

Background A UNICEF review of the challenges to scaling up integrated community case management (iCCM) found that drug shortages were a common bottleneck. In many settings, little thought has gone into the design of supply chains to the community level and limited evidence exists for how to address these unique challenges. SC4CCM’s purpose was to conduct intervention research to identify proven, simple, affordable solutions that address the unique supply chain challenges faced by CHWs and to demonstrate that supply chain constraints at the community level can be overcome. Methods SC4CCM selected three countries to implement supply chain innovations and developed a theory of change (TOC) framework for the learning phase, which identified the main drivers of product availability and was used for baseline assessments, design, implementation and evaluation of interventions in Ethiopia, Malawi, and Rwanda. Interventions were developed in each country and tested over 12–24 months. Mixed–method follow up assessments were conducted in each country in 2012–2013. The Supply Chain for Community Case Management (SC4CCM) Project then simplified the TOC into a Community Health Supply Chain (CHSC) framework to enable cross country analysis Results The findings from interventions in the three countries suggest that the greatest supply chain benefits are realized when all three CHSC framework elements (data flow, product flow, and effective people) are in place and working together. The synergistic effect of these three elements on supply chain performance was most effectively demonstrated by results from the Enhanced Management and Quality Collaborative interventions in Malawi and Rwanda, respectively, which were characterized by lower mean stockout rates and higher in stock rates on day of visit, when compared to other interventions. Conclusions Many conditions are necessary to ensure continuous product availability at the community level, however a supply chain works best when three key elements (product flow, data flow, and effective people) are deliberately included as an integral part of the system design. Although these elements may be designed differently in different settings, streamlining and synchronizing them while ensuring inclusion of all components for each element improves supply chain performance and promotes product availability at the community level. PMID:25520795

DOE Office of Scientific and Technical Information (OSTI.GOV)

Dondero, Rachel Elizabeth

The increased use of Field Programmable Gate Arrays (FPGAs) in critical systems brings new challenges in securing the diversely programmable fabric from cyber-attacks. FPGAs are an inexpensive, efficient, and flexible alternative to Application Specific Integrated Circuits (ASICs), which are becoming increasingly expensive and impractical for low volume manufacturing as technology nodes continue to shrink. Unfortunately, FPGAs are not designed for high security applications, and their high-flexibility lends itself to low security and vulnerability to malicious attacks. Similar to securing an ASIC’s functionality, FPGA programmers can exploit the inherent randomness introduced into hardware structures during fabrication for security applications. Physically Unclonablemore » Functions (PUFs) are one such solution that uses the die specific variability in hardware fabrication for both secret key generation and verification. PUFs strive to be random, unique, and reliable. Throughout recent years many PUF structures have been presented to try and maximize these three design constraints, reliability being the most difficult of the three to achieve. This thesis presents a new PUF structure that combines two elementary PUF concepts (a bi-stable SRAM PUF and a delay-based arbiter PUF) to create a PUF with increased reliability, while maintaining both random and unique qualities. Properties of the new PUF will be discussed as well as the various design modifications that can be made to tweak the desired performance and overhead.« less

Design and testing of a mesocosm-scale habitat for culturing the endangered Devils Hole Pupfish

USGS Publications Warehouse

Feuerbacher, Olin; Bonar, Scott A.; Barrett, Paul J.

2016-01-01

aptive propagation of desert spring fishes, whether for conservation or research, is often difficult, given the unique and often challenging environments these fish utilize in nature. High temperatures, low dissolved oxygen, minimal water flow, and highly variable lighting are some conditions a researcher might need to recreate to simulate their natural environments. Here we describe a mesocosm-scale habitat created to maintain hybrid Devils Hole × Ash Meadows Amargosa Pupfish (Cyprinodon diabolis × C. nevadensis mionectes) under conditions similar to those found in Devils Hole, Nevada. This 13,000-L system utilized flow control and natural processes to maintain these conditions rather than utilizing complex and expensive automation. We designed a rotating solar collector to control natural sunlight, a biological reactor to consume oxygen while buffering water quality, and a reverse-daylight photosynthesis sump system to stabilize nighttime pH and swings in dissolved oxygen levels. This system successfully controlled many desired parameters and helped inform development of a larger, more permanent desert fish conservation facility at the U.S. Fish and Wildlife Service’s Ash Meadows National Wildlife Refuge, Nevada. For others who need to raise fish from unique habitats, many components of the scalable and modular design of this system can be adapted at reasonable cost.

Multigenerational Independent Colony for Extraterrestrial Habitation, Autonomy, and Behavior Health (MICEHAB): An Investigation of a Long Duration, Partial Gravity, Autonomous Rodent Colony

NASA Technical Reports Server (NTRS)

Rodgers, Erica M.; Simon, Matthew A.; Antol, Jeffrey; Chai, Patrick R.; Jones, Christopher A.; Klovstad, Jordan J.; Neilan, James H.; Stillwagen, Frederic H.; Williams, Phillip A.; Bednara, Michael;

The James Webb Space Telescope RealWorld-InWorld Design Challenge: Involving Professionals in a Virtual Classroom

NASA Astrophysics Data System (ADS)

Masetti, Margaret; Bowers, S.

2011-01-01

Students around the country are becoming experts on the James Webb Space Telescope by designing solutions to two of the design challenges presented by this complex mission. RealWorld-InWorld has two parts; the first (the Real World portion) has high-school students working face to face in their classroom as engineers and scientists. The InWorld phase starts December 15, 2010 as interested teachers and their teams of high school students register to move their work into a 3D multi-user virtual world environment. At the start of this phase, college students from all over the country choose a registered team to lead InWorld. Each InWorld team is also assigned an engineer or scientist mentor. In this virtual world setting, each team refines their design solutions and creates a 3D model of the Webb telescope. InWorld teams will use 21st century tools to collaborate and build in the virtual world environment. Each team will learn, not only from their own team members, but will have the opportunity to interact with James Webb Space Telescope researchers through the virtual world setting, which allows for synchronous interactions. Halfway through the challenge, design solutions will be critiqued and a mystery problem will be introduced for each team. The top five teams will be invited to present their work during a synchronous Education Forum April 14, 2011. The top team will earn scholarships and technology. This is an excellent opportunity for professionals in both astronomy and associated engineering disciplines to become involved with a unique educational program. Besides the chance to mentor a group of interested students, there are many opportunities to interact with the students as a guest, via chats and presentations.

Natural photoreceptors and their application to synthetic biology.

PubMed

Schmidt, Daniel; Cho, Yong Ku

2015-02-01

The ability to perturb living systems is essential to understand how cells sense, integrate, and exchange information, to comprehend how pathologic changes in these processes relate to disease, and to provide insights into therapeutic points of intervention. Several molecular technologies based on natural photoreceptor systems have been pioneered that allow distinct cellular signaling pathways to be modulated with light in a temporally and spatially precise manner. In this review, we describe and discuss the underlying design principles of natural photoreceptors that have emerged as fundamental for the rational design and implementation of synthetic light-controlled signaling systems. Furthermore, we examine the unique challenges that synthetic protein technologies face when applied to the study of neural dynamics at the cellular and network level. Published by Elsevier Ltd.

Status of Solid State Lighting Product Development and Future Trends for General Illumination.

PubMed

Katona, Thomas M; Pattison, P Morgan; Paolini, Steve

2016-06-07

After decades of research and development on fabrication of efficient light-emitting diodes (LEDs) throughout the visible spectrum, LED-based lighting has reached unparalleled performance with respect to energy efficiency and has become the light source for virtually all new lighting products being designed today. The development of the core light sources and their subsequent integration into lighting systems continue to present unique challenges and opportunities for product designers. We review these systems and the current development status, as well as provide context for the trends in solid state lighting that are leading to the development of value-added lighting solutions that extend the domain of lighting beyond light generation, into fields as diverse as communications, healthcare, and agricultural production.

Informal physics learning from video games: a case study using gameplay videos

NASA Astrophysics Data System (ADS)

Croxton, DeVaughn; Kortemeyer, Gerd

2018-01-01

Researching informal gameplay can be challenging, since as soon as a formal study design is imposed, it becomes neither casual nor self-motivated. As a case study of a non-invasive design, we analyze publicly posted gameplay videos to assess the effectiveness of a physics educational video game on special relativity. These videos offer unique insights into informal learning through gaming, as players do not only describe the gameplay mechanics, but also explore physics concepts in a think-aloud fashion while they ponder the experience and effects. We find that while this methodology has substantial limitations, it is complementary when it comes to assessing motivations and attitudes, as well as to gathering data on conceptual hurdles.

Post-Closure Challenges of U.S. Department of Energy Sites in Desert Environments of the Southwestern United States - 12095

DOE Office of Scientific and Technical Information (OSTI.GOV)

Gil, April; Steckley, Deborah; Gauthier, Cassie

2012-07-01

U.S. Department of Energy (DOE) sites located in harsh desert environments of the Four Corners region of the southwestern United States require diligence and continual maintenance to ensure the remediation systems function as designed to protect human health and the environment. The geology and climate of this area create issues that are unique to these sites. Geologic formations contain naturally occurring constituents that are often the same as the residual contaminants remaining from historical milling activities at the sites. Although annual precipitation is low, when precipitation events occur they can be of extreme intensity, resulting in erosion and flooding thatmore » can quickly destroy infrastructure and rapidly change site conditions. Winds can cause sand storms and sand mounding that effect site features. These challenging environmental conditions, along with the remote locations of the sites, require active management beyond what was originally envisioned for uranium disposal sites to address concerns in a safe and cost-effective manner. The unique environment of the Four Corners region creates many challenges to the LTSM of LM sites in southwestern United States. The remediation efforts and approaches to infrastructure have to be specifically structured to work in this environment. Often, the systems and structures have to be modified based on lessons learned on how to best adapt to these difficult conditions and remote locations. These sites require continual maintenance and additional efforts compared to many other LM sites. (authors)« less

Measurement and Instrumentation Challenges at X-ray Free Electron Lasers

NASA Astrophysics Data System (ADS)

Feng, Yiping

2015-03-01

X-ray Free Electron Laser sources based on the Self Amplified Spontaneous Emission process are intrinsically chaotic, giving rise to pulse-to-pulse fluctuations in all physical properties, including intensity, position and pointing, spatial and temporal profiles, spectral content, timing, and coherence. These fluctuations represents special challenges to users whose experiments are designed to reveal small changes in the underlying physical quantities, which would otherwise be completely washed out without using the proper diagnostics tools. Due to the X-ray FEL's unique characteristics such as the unprecedented peak power and nearly full spatial coherence, there are many technical challenges in conceiving and implementing these devices that are highly transmissive, provide sufficient signal-to-noise ratio, and most importantly work in the single-shot mode. Portions of this research were carried out at the Linac Coherent Light Source (LCLS) at the SLAC National Accelerator Laboratory. LCLS is an Office of Science User Facility operated for the U.S. Department of Energy Office of Science by Stanford Univ.

Developing design principles for a Virtual Hospice: improving access to care.

PubMed

Taylor, Andrea; French, Tara; Raman, Sneha

2018-03-01

Providing access to hospice services will become increasingly difficult due to the pressures of an ageing population and limited resources. To help address this challenge, a small number of services called Virtual Hospice have been established. This paper presents early-stage design work on a Virtual Hospice to improve access to services provided by a hospice (Highland Hospice) serving a largely remote and rural population in Scotland, UK. The study was structured as a series of Experience Labs with Highland Hospice staff, healthcare professionals and patients. Experience Labs employ a participatory design approach where participants are placed at the centre of the design process, helping to ensure that the resultant service meets their needs. Data from the Experience Labs were analysed using qualitative thematic analysis and design analysis. A number of themes and barriers to accessing Highland Hospice services were identified. In response, an initial set of seven design principles was developed. Design principles are high-level guidelines that are used to improve prioritisation and decision making during the design process by ensuring alignment with research insights. The design principles were piloted with a group of stakeholders and gained positive feedback. The design principles are intended to guide the ongoing development of the Highland Hospice Virtual Hospice. However, the challenges faced by Highland Hospice in delivering services in a largely remote and rural setting are not unique. The design principles, encompassing digital and non-digital guidelines, or the design approach could be applied by other hospices in the UK or overseas. © Article author(s) (or their employer(s) unless otherwise stated in the text of the article) 2018. All rights reserved. No commercial use is permitted unless otherwise expressly granted.

Critical Design Issues of Tokamak Cooling Water System of ITER's Fusion Reactor

DOE Office of Scientific and Technical Information (OSTI.GOV)

Kim, Seokho H; Berry, Jan

U.S. ITER is responsible for the design, engineering, and procurement of the Tokamak Cooling Water System (TCWS). The TCWS transfers heat generated in the Tokamak to cooling water during nominal pulsed operation 850 MW at up to 150 C and 4.2 MPa water pressure. This water contains radionuclides because impurities (e.g., tritium) diffuse from in-vessel components and the vacuum vessel by water baking at 200 240 C at up to 4.4MPa, and corrosion products become activated by neutron bombardment. The system is designated as safety important class (SIC) and will be fabricated to comply with the French Order concerning nuclearmore » pressure equipment (December 2005) and the EU Pressure Equipment Directive using ASME Section VIII, Div 2 design codes. The complexity of the TCWS design and fabrication presents unique challenges. Conceptual design of this one-of-a-kind cooling system has been completed with several issues that need to be resolved to move to next stage of the design. Those issues include flow balancing between over hundreds of branch pipelines in parallel to supply cooling water to blankets, determination of optimum flow velocity while minimizing the potential for cavitation damage, design for freezing protection for cooling water flowing through cryostat (freezing) environment, requirements for high-energy piping design, and electromagnetic impact to piping and components. Although the TCWS consists of standard commercial components such as piping with valves and fittings, heat exchangers, and pumps, complex requirements present interesting design challenges. This paper presents a brief description of TCWS conceptual design and critical design issues that need to be resolved.« less

The Challenges of Career and Technical Education Concurrent Enrollment: An Administrative Perspective

ERIC Educational Resources Information Center

Haag, Patricia W.

2015-01-01

Career and technical education concurrent enrollment may pose unique challenges in programming and enrollment for program administrators, and this chapter describes the experiences and challenges of a CTE concurrent enrollment administrator.

Voluntary switching between identities in dissociative identity disorder: A functional MRI case study.

PubMed

Savoy, R L; Frederick, B B; Keuroghlian, A S; Wolk, P C

2012-01-01

Patients who suffer from dissociative identity disorder present unique scientific and clinical challenges for psychology and psychiatry. We have been fortunate in working with a patient who-while undergoing functional MRI-can switch rapidly and voluntarily between her main personality (a middle-aged, high-functioning woman) and an alternate personality (a 4-6-year-old girl). A unique task was designed to isolate the processes occurring during the switches between these personalities. Data are from two imaging sessions, conducted months apart, each showing the same activated areas during switches between these personalities. The activated areas include the following: the primary sensory and motor cortex, likely associated with characteristic facial movements made during switching; the nucleus accumbens bilaterally, possibly associated with aspects of reward connected with switching; and prefrontal sites, presumably associated with the executive control involved in the switching of personalities.

Synthetic Immunology: Hacking Immune Cells to Expand Their Therapeutic Capabilities.

PubMed

Roybal, Kole T; Lim, Wendell A

2017-04-26

The ability of immune cells to survey tissues and sense pathologic insults and deviations makes them a unique platform for interfacing with the body and disease. With the rapid advancement of synthetic biology, we can now engineer and equip immune cells with new sensors and controllable therapeutic response programs to sense and treat diseases that our natural immune system cannot normally handle. Here we review the current state of engineered immune cell therapeutics and their unique capabilities compared to small molecules and biologics. We then discuss how engineered immune cells are being designed to combat cancer, focusing on how new synthetic biology tools are providing potential ways to overcome the major roadblocks for treatment. Finally, we give a long-term vision for the use of synthetic biology to engineer immune cells as a general sensor-response platform to precisely detect disease, to remodel disease microenvironments, and to treat a potentially wide range of challenging diseases.

Oman's coral reefs: A unique ecosystem challenged by natural and man-related stresses and in need of conservation.

PubMed

Burt, J A; Coles, S; van Lavieren, H; Taylor, O; Looker, E; Samimi-Namin, K

2016-04-30

Oman contains diverse and abundant reef coral communities that extend along a coast that borders three environmentally distinct water bodies, with corals existing under unique and often stressful environmental conditions. In recent years Oman's reefs have undergone considerable change due to recurrent predatory starfish outbreaks, cyclone damage, harmful algal blooms, and other stressors. In this review we summarize current knowledge of the biology and status of corals in Oman, particularly in light of recent stressors and projected future threats, and examine current reef management practices. Oman's coral communities occur in marginal environmental conditions for reefs, and hence are quite vulnerable to anthropogenic effects. We recommend a focus on developing conservation-oriented coral research to guide proactive management and expansion of the number and size of designated protected areas in Oman, particularly those associated with critical coral habitat. Copyright © 2015 The Authors. Published by Elsevier Ltd.. All rights reserved.

Ethical Issues in Research Involving Participants With Opioid Use Disorder.

PubMed

Anderson, Emily; McNair, Lindsay

2018-05-01

In the current epidemic of opioid use disorders, there is both a scientific and ethical imperative to develop effective medical and behavioral treatments for opioid addiction. Research in subject populations with active and ongoing drug addictions bring unique ethical considerations and challenges. Sponsors, researchers, and institutional review board (IRB) members should be familiar with these unique ethical and medical issues as they design, review, and conduct research planned for this population. Issues include those of informed consent and decision-making capacity of research participants, compensation for participation and concerns about undue inducement, forces that threaten the voluntary nature of research participation including the scarcity of available drug treatment programs, and ensuring that participants are aware of and understand risks that may continue after research participation such as increased risk of overdose after research-mandated drug abstinence. This manuscript discusses the current thinking on these issues.

Synthetic Immunology: Hacking Immune Cells to Expand Their Therapeutic Capabilities

PubMed Central

Roybal, Kole T.; Lim, Wendell A.

2017-01-01

The ability of immune cells to survey tissues and sense pathologic insults and deviations makes them a unique platform for interfacing with the body and disease. With the rapid advancement of synthetic biology, we can now engineer and equip immune cells with new sensors and controllable therapeutic response programs to sense and treat diseases that our natural immune system cannot normally handle. Here we review the current state of engineered immune cell therapeutics and their unique capabilities compared to small molecules and biologics. We then discuss how engineered immune cells are being designed to combat cancer, focusing on how new synthetic biology tools are providing potential ways to overcome the major roadblocks for treatment. Finally, we give a long-term vision for the use of synthetic biology to engineer immune cells as a general sensor-response platform to precisely detect disease, to remodel disease microenvironments, and to treat a potentially wide range of challenging diseases. PMID:28446063

Conceptual Drivers for an Exploration Medical System

NASA Technical Reports Server (NTRS)

Antonsen, E.; Canga, M.

2016-01-01

Interplanetary spaceflight provides unique challenges that have not been encountered in prior spaceflight experience. Extended distance and timeframes introduce new challenges such as an inability to resupply medications and consumables, inability to evacuate injured or ill crew, and communication delays that introduce a requirement for some level of autonomous medical capability. Because of these challenges the approaches used in prior programs have limited application to a proposed three year Mars mission. This paper proposes a paradigm shift in the approach to medical risk mitigation for crew health and mission objectives threatened by inadequate medical capabilities in the setting of severely limited resources. A conceptual approach is outlined to derive medical system and vehicle needs from an integrated vision of how medical care will be provided within this new paradigm. Using NASA Design Reference Missions this process assesses each mission phase to deconstruct medical needs at any point during a mission. Two operational categories are proposed, nominal operations (pre-planned activities) and contingency operations (medical conditions requiring evaluation) that meld clinical needs and research needs into a single system. These definitions are used to derive a task level analysis to support quantifiable studies into a medical capabilities trade. This trade allows system design to proceed from both a mission centric and ethics-based approach to medical limitations in an exploration class mission.

Theoretical modelling and optimization of bubble column dehumidifier for a solar driven humidification-dehumidification system

NASA Astrophysics Data System (ADS)

Ranjitha, P. Raj; Ratheesh, R.; Jayakumar, J. S.; Balakrishnan, Shankar

2018-02-01

Availability and utilization of energy and water are the top most global challenges being faced by the new millennium. At the present state water scarcity has become a global as well as a regional challenge. 40 % of world population faces water shortage. Challenge of water scarcity can be tackled only with increase in water supply beyond what is obtained from hydrological cycle. This can be achieved either by desalinating the sea water or by reusing the waste water. High energy requirement need to be overcome for either of the two processes. Of many desalination technologies, humidification dehumidification (HDH) technology powered by solar energy is widely accepted for small scale production. Detailed optimization studies on system have the potential to effectively utilize the solar energy for brackish water desalination. Dehumidification technology, specifically, require further study because the dehumidifier effectiveness control the energetic performance of the entire HDH system. The reason attributes to the high resistance involved to diffuse dilute vapor through air in a dehumidifier. The present work intends to optimize the design of a bubble column dehumidifier for a solar energy driven desalination process. Optimization is carried out using Matlab simulation. Design process will identify the unique needs of a bubble column dehumidifier in HDH system.

Challenges to Laser-Based Imaging Techniques in Gas Turbine Combustor Systems for Aerospace Applications

NASA Technical Reports Server (NTRS)

Locke, Randy J.; Anderson, Robert C.; Zaller, Michelle M.; Hicks, Yolanda R.

1998-01-01

Increasingly severe constraints on emissions, noise and fuel efficiency must be met by the next generation of commercial aircraft powerplants. At NASA Lewis Research Center (LeRC) a cooperative research effort with industry is underway to design and test combustors that will meet these requirements. To accomplish these tasks, it is necessary to gain both a detailed understanding of the combustion processes and a precise knowledge of combustor and combustor sub-component performance at close to actual conditions. To that end, researchers at LeRC are engaged in a comprehensive diagnostic investigation of high pressure reacting flowfields that duplicate conditions expected within the actual engine combustors. Unique, optically accessible flame-tubes and sector rig combustors, designed especially for these tests. afford the opportunity to probe these flowfields with the most advanced, laser-based optical diagnostic techniques. However, these same techniques, tested and proven on comparatively simple bench-top gaseous flame burners, encounter numerous restrictions and challenges when applied in these facilities. These include high pressures and temperatures, large flow rates, liquid fuels, remote testing, and carbon or other material deposits on combustor windows. Results are shown that document the success and versatility of these nonintrusive optical diagnostics despite the challenges to their implementation in realistic systems.

Outdoor physical activity for older people-the senior exercise park: Current research, challenges and future directions.

PubMed

Levinger, Pazit; Sales, Myrla; Polman, Remco; Haines, Terry; Dow, Briony; Biddle, Stuart J H; Duque, Gustavo; Hill, Keith D

2018-03-14

Exercising outdoors provide beneficial effect on mental and physical health for all ages. However, few older people exercise outdoors other than walking. While outdoor gyms have become increasingly common in Australia, limited outdoor exercise equipment specifically designed for older people is available in public spaces. We have set up and evaluated a unique purpose-built outdoor exercise park for older people in the community setting and demonstrated positive physical and well-being outcomes associated with the provision of this unique exercise mode and social programme. This study is a reflective narrative describing this innovative exercise approach and reports challenges associated with establishment of the exercise park, conducting the randomised trial, strategies adopted to address these challenges and recommendations for future implementation of this approach in the community. Many challenges were encountered, including securing appropriate land to locate the exercise park, control of environmental factors for safety (non-slippery ground and equipment) as well as logistics in running the exercise programme itself. Several adjustments in the equipment were also required to ensure safe use by older people. The inclusion of outdoor equipment for older people in public spaces or urban parks is important and careful consideration needs to be taken by local/public authorities to provide access, amenities and safety for all as well as activities to suit all ages. SO WHAT?: Seniors' exercise parks can be installed in public places and may provide an enjoyable and effective approach to engage older individuals in a more active and healthier lifestyle. © 2018 The Authors. Health Promotion Journal of Australia published by John Wiley & Sons Australia, Ltd on behalf of Australian Health Promotion Association.

MSAT-X: A technical introduction and status report

NASA Technical Reports Server (NTRS)

Dessouky, Khaled; Sue, Miles

1988-01-01

A technical introduction and status report for the Mobile Satellite Experiment (MSAT-X) program is presented. The concepts of a Mobile Satellite System (MSS) and its unique challenges are introduced. MSAT-X's role and objectives are delineated with focus on its achievements. An outline of MSS design philosophy is followed by a presentation and analysis of the MSAT-X results, which are cast in a broader context of an MSS. The current phase of MSAT-X has focused notably on the ground segment of MSS. The accomplishments in the four critical technology areas of vehicle antennas, modem and mobile terminal design, speech coding, and networking are presented. A concise evolutionary trace is incorporated in each area to elucidate the rationale leading to the current design choices. The findings in the area of propagation channel modeling are also summarized and their impact on system design discussed. To facilitate the assessment of the MSAT-X results, technology and subsystem recommendations are also included and integrated with a quantitative first-generation MSS design.

Mechanical Design of Carbon Ion Optics

NASA Technical Reports Server (NTRS)

Haag, Thomas

2005-01-01

Carbon Ion Optics are expected to provide much longer thruster life due to their resistance to sputter erosion. There are a number of different forms of carbon that have been used for fabricating ion thruster optics. The mechanical behavior of carbon is much different than that of most metals, and poses unique design challenges. In order to minimize mission risk, the behavior of carbon must be well understood, and components designed within material limitations. Thermal expansion of the thruster structure must be compatible with thermal expansion of the carbon ion optics. Specially designed interfaces may be needed so that grid gap and aperture alignment are not adversely affected by dissimilar material properties within the thruster. The assembled thruster must be robust and tolerant of launch vibration. The following paper lists some of the characteristics of various carbon materials. Several past ion optics designs are discussed, identifying strengths and weaknesses. Electrostatics and material science are not emphasized so much as the mechanical behavior and integration of grid electrodes into an ion thruster.

Propulsion Design With Freeform Fabrication (PDFF)

NASA Technical Reports Server (NTRS)

Barnes, Daudi; McKinnon, James; Priem, Richard

2010-01-01

The nation is challenged to decrease the cost and schedule to develop new space transportation propulsion systems for commercial, scientific, and military purposes. Better design criteria and manufacturing techniques for small thrusters are needed to meet current applications in missile defense, space, and satellite propulsion. The requirements of these systems present size, performance, and environmental demands on these thrusters that have posed significant challenges to the current designers and manufacturers. Designers are limited by manufacturing processes, which are complex, costly, and time consuming, and ultimately limited in their capabilities. The PDFF innovation vastly extends the design opportunities of rocket engine components and systems by making use of the unique manufacturing freedom of solid freeform rapid prototype manufacturing technology combined with the benefits of ceramic materials. The unique features of PDFF are developing and implementing a design methodology that uses solid freeform fabrication (SFF) techniques to make propulsion components with significantly improved performance, thermal management, power density, and stability, while reducing development and production costs. PDFF extends the design process envelope beyond conventional constraints by leveraging the key feature of the SFF technique with the capability to form objects with nearly any geometric complexity without the need for elaborate machine setup. The marriage of SFF technology to propulsion components allows an evolution of design practice to harmonize material properties with functional design efficiency. Reduced density of materials when coupled with the capability to honeycomb structure used in the injector will have significant impact on overall mass reduction. Typical thrusters in use for attitude control have 60 90 percent of its mass in the valve and injector, which is typically made from titanium. The combination of material and structure envisioned for use in an SFF thruster design could reduce thruster weight by a factor of two or more. The thrust-to-weight ratios for such designs can achieve 1,000:1 or more, depending on chamber pressure. The potential exists for continued development in materials, size, speed, accuracy of SFF techniques, which can lead to speculative developments of PDFF processes such as fabrication of custom human interface devices like masks, chairs, and clothing, and advanced biomedical application to human organ reconstruction. Other potential applications are: higher fidelity lower cost test fixtures for probes and inspection, disposable thrusters, and ISRU (in situ resource utilization) for component production in space or on Lunar and Martian missions, and application for embedding MEMS (microelectromechanical systems) during construction process of form changing aerostructure/dynamic structures.

Operation Protective Edge - A Unique Challenge for a Civilian EMS Agency.

PubMed

Jaffe, Eli; Strugo, Refael; Wacht, Oren

2015-10-01

During July through August 2014, Operation Protective Edge, a military conflict between Israel and the Hamas regime in Gaza, dramatically affected both populations. Magen David Adom (MDA), the Israeli national Emergency Medical Service (EMS) and a member of the Red Cross, faced a unique challenge during the conflict: to continue providing crucial service to the entire civilian population of Israel, which was under constant missile threat. This challenge included not only providing immediate care for routine EMS calls under missile threat, but also preparing and delivering immediate care to civilians injured in attacks on major cities, as well as small communities, in Israel. This task is a challenge for a civilian EMS agency that normally operates in a non-military environment, yet, in an instant, must enhance its capability to respond to a considerable threat to its population. During Operation Protective Edge, MDA provided care for 842 wounded civilians and utilized a significant amount of its resources. Providing EMS services for a civilian population in a mixed civilian/military scenario is a challenging task on a national level for an EMS system, especially when the threat lasts for weeks. This report describes MDA's preparedness and operations during Operation Protective Edge, and the unique EMS challenges and dilemmas the agency faced.

How to design a single-cell RNA-sequencing experiment: pitfalls, challenges and perspectives.

PubMed

Dal Molin, Alessandra; Di Camillo, Barbara

2018-01-31

The sequencing of the transcriptome of single cells, or single-cell RNA-sequencing, has now become the dominant technology for the identification of novel cell types in heterogeneous cell populations or for the study of stochastic gene expression. In recent years, various experimental methods and computational tools for analysing single-cell RNA-sequencing data have been proposed. However, most of them are tailored to different experimental designs or biological questions, and in many cases, their performance has not been benchmarked yet, thus increasing the difficulty for a researcher to choose the optimal single-cell transcriptome sequencing (scRNA-seq) experiment and analysis workflow. In this review, we aim to provide an overview of the current available experimental and computational methods developed to handle single-cell RNA-sequencing data and, based on their peculiarities, we suggest possible analysis frameworks depending on specific experimental designs. Together, we propose an evaluation of challenges and open questions and future perspectives in the field. In particular, we go through the different steps of scRNA-seq experimental protocols such as cell isolation, messenger RNA capture, reverse transcription, amplification and use of quantitative standards such as spike-ins and Unique Molecular Identifiers (UMIs). We then analyse the current methodological challenges related to preprocessing, alignment, quantification, normalization, batch effect correction and methods to control for confounding effects. © The Author(s) 2018. Published by Oxford University Press. All rights reserved. For Permissions, please email: journals.permissions@oup.com.

Financial stability in biobanking: unique challenges for disease-focused foundations and patient advocacy organizations.

PubMed

Bromley, Russell L

2014-10-01

In the last decade, many disease-focused foundations and patient advocacy organizations that support biomedical research have created patient registries and biobanks. This article reviews the motivations behind the creation of those biobanks and how they are different from biobanks sponsored by government or industry. It also discusses some of the different funding models being employed by these organizations. Finally, it highlights some of the unique challenges faced by disease-focused foundations and advocacy organizations that sponsor biobanks, and how they are overcoming those challenges to achieve both financial and operational sustainability.

Rural Asthma: Current Understanding of Prevalence, Patterns, and Interventions for Children and Adolescents.

PubMed

Estrada, Robin Dawson; Ownby, Dennis R

2017-06-01

Asthma is the most common chronic illness of children and adolescents in the USA. While asthma has been understood to disproportionately affect urban dwellers, recent investigations have revealed rural pediatric asthma prevalence to be very similar to urban and to be more closely correlated with socioeconomic and environmental factors than geographic location or population density. Rural children experience factors unique to location that impact asthma development and outcomes, including housing quality, cigarette smoke exposure, and small/large-scale farming. Additionally, there are challenging barriers to appropriate asthma care that frequently are more severe for those living in rural areas, including insurance status, lack of primary care providers and pulmonary specialists, knowledge deficits (both patient and provider), and a lack of culturally tailored asthma interventions. Interventions designed to address rural pediatric asthma disparities are more likely to be successful when targeted to specific challenges, such as the use of school-based services or telemedicine to mitigate asthma care access issues. Continued research on understanding the complex interaction of specific rural environmental factors with host factors can inform future interventions designed to mitigate asthma disparities.

Challenges with Operating a Water Recovery System (WRS) in the Microgravity Environment of the International Space Station (ISS)

NASA Technical Reports Server (NTRS)

Carter, Donald Layne

2017-01-01

The ISS WRS produces potable water from crew urine, crew latent, and Sabatier product water. This system has been operational on ISS since November 2008, producing over 30,000 L of water during that time. The WRS includes a Urine Processor Assembly (UPA) to produce a distillate from the crew urine. This distillate is combined with the crew latent and Sabatier product water and further processed by the Water Processor Assembly (WPA) to the potable water. The UPA and WPA use technologies commonly used on ISS for water purification, including filtration, distillation, adsorption, ion exchange, and catalytic oxidation. The primary challenge with the design and operation of the WRS has been with implementing these technologies in microgravity. The absence of gravity has created unique issues that impact the constituency of the waste streams, alter two-phase fluid dynamics, and increases the impact of particulates on system performance. NASA personnel continue to pursue upgrades to the existing design to improve reliability while also addressing their viability for missions beyond ISS.

Nanofluidics in two-dimensional layered materials: inspirations from nature.

PubMed

Gao, Jun; Feng, Yaping; Guo, Wei; Jiang, Lei

2017-08-29

With the advance of chemistry, materials science, and nanotechnology, significant progress has been achieved in the design and application of synthetic nanofluidic devices and materials, mimicking the gating, rectifying, and adaptive functions of biological ion channels. Fundamental physics and chemistry behind these novel transport phenomena on the nanoscale have been explored in depth on single-pore platforms. However, toward real-world applications, one major challenge is to extrapolate these single-pore devices into macroscopic materials. Recently, inspired partially by the layered microstructure of nacre, the material design and large-scale integration of artificial nanofluidic devices have stepped into a completely new stage, termed 2D nanofluidics. Unique advantages of the 2D layered materials have been found, such as facile and scalable fabrication, high flux, efficient chemical modification, tunable channel size, etc. These features enable wide applications in, for example, biomimetic ion transport manipulation, molecular sieving, water treatment, and nanofluidic energy conversion and storage. This review highlights the recent progress, current challenges, and future perspectives in this emerging research field of "2D nanofluidics", with emphasis on the thought of bio-inspiration.

Designing health care risk management on-line:meeting regulators' concerns for fixed-hour curriculum.

PubMed

Hyer, Kathryn; Taylor, Heidi H; Nanni, Kennith

2004-01-01

This paper describes the experience of creating a continuing professional education on-line risk management program that is designed to meet Florida's educational requirements for licensure as a risk manager in health-care settings and details the challenges faced when the in-class didactic program of 15 eight-hour sessions is reformatted as an on-line program. Structuring instructor/learner interactivity remains a challenge, especially if the program allows learner control and is a key feature in marketing the program. The article presents the dilemmas for state regulators as they work to determine if the on-line program meets legislative intent and statutory requirements because the learning platform does not have a clock function that accumulates time for each learner. While some details reflect the uniqueness of the 120-hour educational requirements for risk managers in Florida, the experience of the authors provides insight into the development of continuing professional education distance learning programs that are multidisciplinary and move primarily from a time-based format into a curriculum that uses time as only one dimension of the evaluation of learning.

Assemby, test, and launch operations for the Mars Exploration Rovers

NASA Technical Reports Server (NTRS)

Wallace, Matthew T.; Hardy, Paul V.; Romero, Raul A.; Salvo, Christopher G.; Shain, Thomas W.; Thompson, Arthur D.; Wirth, John W.

2005-01-01

In January of 2004, NASA's twin Mars rovers, Spirit and Opportunity, successfully landed on opposite sides of the Red Planet after a seven month Earth to Mars cruise period. Both vehicles have operated well beyond their 90 day primary mission design life requirements. The Assembly, Test, and Launch Operations (ATLO) program for these missions presented unique technical and schedule challenges to the team at the Jet Propulsion Laboratory (JPL). Among these challenges were a highly compressed schedule and late deliveries leading to extended double shift staffing, dual spacecraft operations requiring test program diversification and resource arbitration, multiple atypical test configurations for airbag/rocket landings and surface mobility testing, and verification of an exceptionally large number of separations, deployments, and mechanisms. This paper discusses the flight system test philosophies and approach, and presents lessons learned.

The Electric Power System of the International Space Station: A Platform for Power Technology Development

NASA Technical Reports Server (NTRS)

Gietl, Eric B.; Gholdston, Edward W.; Manners, Bruce A.; Delventhal, Rex A.

2000-01-01

The electrical power system developed for the International Space Station represents the largest space-based power system ever designed and, consequently, has driven some key technology aspects and operational challenges. The full U.S.-built system consists of a 160-Volt dc primary network, and a more tightly regulated 120-Volt dc secondary network. Additionally, the U.S. system interfaces with the 28-Volt system in the Russian segment. The international nature of the Station has resulted in modular converters, switchgear, outlet panels, and other components being built by different countries, with the associated interface challenges. This paper provides details of the architecture and unique hardware developed for the Space Station, and examines the opportunities it provides for further long-term space power technology development, such as concentrating solar arrays and flywheel energy storage systems.

Evaluating Sensory Processing in Fragile X Syndrome: Psychometric Analysis of the Brain Body Center Sensory Scales (BBCSS).

PubMed

Kolacz, Jacek; Raspa, Melissa; Heilman, Keri J; Porges, Stephen W

2018-06-01

Individuals with fragile X syndrome (FXS), especially those co-diagnosed with autism spectrum disorder (ASD), face many sensory processing challenges. However, sensory processing measures informed by neurophysiology are lacking. This paper describes the development and psychometric properties of a parent/caregiver report, the Brain-Body Center Sensory Scales (BBCSS), based on Polyvagal Theory. Parents/guardians reported on 333 individuals with FXS, 41% with ASD features. Factor structure using a split-sample exploratory-confirmatory design conformed to neurophysiological predictions. Internal consistency, test-retest, and inter-rater reliability were good to excellent. BBCSS subscales converged with the Sensory Profile and Sensory Experiences Questionnaire. However, data also suggest that BBCSS subscales reflect unique features related to sensory processing. Individuals with FXS and ASD features displayed more sensory challenges on most subscales.

Spleen transcriptome response to infection with avian pathogenic Escherichia coli in broiler chickens

PubMed Central

2011-01-01

Background Avian pathogenic Escherichia coli (APEC) is detrimental to poultry health and its zoonotic potential is a food safety concern. Regulation of antimicrobials in food-production animals has put greater focus on enhancing host resistance to bacterial infections through genetics. To better define effective mechanism of host resistance, global gene expression in the spleen of chickens, harvested at two times post-infection (PI) with APEC, was measured using microarray technology, in a design that will enable investigation of effects of vaccination, challenge, and pathology level. Results There were 1,101 genes significantly differentially expressed between severely infected and non-infected groups on day 1 PI and 1,723 on day 5 PI. Very little difference was seen between mildly infected and non-infected groups on either time point. Between birds exhibiting mild and severe pathology, there were 2 significantly differentially expressed genes on day 1 PI and 799 on day 5 PI. Groups with greater pathology had more genes with increased expression than decreased expression levels. Several predominate immune pathways, Toll-like receptor, Jak-STAT, and cytokine signaling, were represented between challenged and non-challenged groups. Vaccination had, surprisingly, no detectible effect on gene expression, although it significantly protected the birds from observable gross lesions. Functional characterization of significantly expressed genes revealed unique gene ontology classifications during each time point, with many unique to a particular treatment or class contrast. Conclusions More severe pathology caused by APEC infection was associated with a high level of gene expression differences and increase in gene expression levels. Many of the significantly differentially expressed genes were unique to a particular treatment, pathology level or time point. The present study not only investigates the transcriptomic regulations of APEC infection, but also the degree of pathology associated with that infection. This study will allow for greater discovery into host mechanisms for disease resistance, providing targets for marker assisted selection and advanced drug development. PMID:21951686

Spleen transcriptome response to infection with avian pathogenic Escherichia coli in broiler chickens.

PubMed

Sandford, Erin E; Orr, Megan; Balfanz, Emma; Bowerman, Nate; Li, Xianyao; Zhou, Huaijun; Johnson, Timothy J; Kariyawasam, Subhashinie; Liu, Peng; Nolan, Lisa K; Lamont, Susan J

2011-09-27

Avian pathogenic Escherichia coli (APEC) is detrimental to poultry health and its zoonotic potential is a food safety concern. Regulation of antimicrobials in food-production animals has put greater focus on enhancing host resistance to bacterial infections through genetics. To better define effective mechanism of host resistance, global gene expression in the spleen of chickens, harvested at two times post-infection (PI) with APEC, was measured using microarray technology, in a design that will enable investigation of effects of vaccination, challenge, and pathology level. There were 1,101 genes significantly differentially expressed between severely infected and non-infected groups on day 1 PI and 1,723 on day 5 PI. Very little difference was seen between mildly infected and non-infected groups on either time point. Between birds exhibiting mild and severe pathology, there were 2 significantly differentially expressed genes on day 1 PI and 799 on day 5 PI. Groups with greater pathology had more genes with increased expression than decreased expression levels. Several predominate immune pathways, Toll-like receptor, Jak-STAT, and cytokine signaling, were represented between challenged and non-challenged groups. Vaccination had, surprisingly, no detectible effect on gene expression, although it significantly protected the birds from observable gross lesions. Functional characterization of significantly expressed genes revealed unique gene ontology classifications during each time point, with many unique to a particular treatment or class contrast. More severe pathology caused by APEC infection was associated with a high level of gene expression differences and increase in gene expression levels. Many of the significantly differentially expressed genes were unique to a particular treatment, pathology level or time point. The present study not only investigates the transcriptomic regulations of APEC infection, but also the degree of pathology associated with that infection. This study will allow for greater discovery into host mechanisms for disease resistance, providing targets for marker assisted selection and advanced drug development.

Trace chemical contaminant generation rates for spacecraft contamination control system design

NASA Technical Reports Server (NTRS)

Perry, J. L.

1995-01-01

A spacecraft presents a unique design challenge with respect to providing a comfortable environment in which people can live and work. All aspects of the spacecraft environmental design including the size of the habitable volume, its temperature, relative humidity, and composition must be considered to ensure the comfort and health of the occupants. The crew members and the materials selected for outfitting the spacecraft play an integral part in designing a habitable spacecraft because material offgassing and human metabolism are the primary sources for continuous trace chemical contaminant generation onboard a spacecraft. Since these contamination sources cannot be completely eliminated, active control processes must be designed and deployed onboard the spacecraft to ensure an acceptably clean cabin atmosphere. Knowledge of the expected rates at which contaminants are generated is very important to the design of these processes. Data from past spacecraft missions and human contaminant production studies have been analyzed to provide this knowledge. The resulting compilation of contaminants and generation rates serve as a firm basis for past, present, and future contamination control system designs for space and aeronautics applications.

A biopolymer-like metal enabled hybrid material with exceptional mechanical prowess

DOE PAGES

Zhang, Junsong; Cui, Lishan; Jiang, Daqiang; ...

2015-02-10

In this study, the design principles for naturally occurring biological materials have inspired us to develop next-generation engineering materials with remarkable performance. Nacre, commonly referred to as nature's armor, is renowned for its unusual combination of strength and toughness. Nature's wisdom in nacre resides in its elaborate structural design and the judicious placement of a unique organic biopolymer with intelligent deformation features. However, up to now, it is still a challenge to transcribe the biopolymer's deformation attributes into a stronger substitute in the design of new materials. In this study, we propose a new design strategy that employs shape memorymore » alloy to transcribe the "J-curve'' mechanical response and uniform molecular/atomic level deformation of the organic biopolymer in the design of high-performance hybrid materials. This design strategy is verified in a TiNi-Ti 3Sn model material system. The model material demonstrates an exceptional combination of mechanical properties that are superior to other high-performance metal-based lamellar composites known to date. Our design strategy creates new opportunities for the development of high-performance bio-inspired materials.« less

A biopolymer-like metal enabled hybrid material with exceptional mechanical prowess

PubMed Central

Zhang, Junsong; Cui, Lishan; Jiang, Daqiang; Liu, Yinong; Hao, Shijie; Ren, Yang; Han, Xiaodong; Liu, Zhenyang; Wang, Yunzhi; Yu, Cun; Huan, Yong; Zhao, Xinqing; Zheng, Yanjun; Xu, Huibin; Ren, Xiaobing; Li, Xiaodong

2015-01-01

The design principles for naturally occurring biological materials have inspired us to develop next-generation engineering materials with remarkable performance. Nacre, commonly referred to as nature's armor, is renowned for its unusual combination of strength and toughness. Nature's wisdom in nacre resides in its elaborate structural design and the judicious placement of a unique organic biopolymer with intelligent deformation features. However, up to now, it is still a challenge to transcribe the biopolymer's deformation attributes into a stronger substitute in the design of new materials. In this study, we propose a new design strategy that employs shape memory alloy to transcribe the “J-curve” mechanical response and uniform molecular/atomic level deformation of the organic biopolymer in the design of high-performance hybrid materials. This design strategy is verified in a TiNi-Ti3Sn model material system. The model material demonstrates an exceptional combination of mechanical properties that are superior to other high-performance metal-based lamellar composites known to date. Our design strategy creates new opportunities for the development of high-performance bio-inspired materials. PMID:25665501

A biopolymer-like metal enabled hybrid material with exceptional mechanical prowess.

PubMed

Zhang, Junsong; Cui, Lishan; Jiang, Daqiang; Liu, Yinong; Hao, Shijie; Ren, Yang; Han, Xiaodong; Liu, Zhenyang; Wang, Yunzhi; Yu, Cun; Huan, Yong; Zhao, Xinqing; Zheng, Yanjun; Xu, Huibin; Ren, Xiaobing; Li, Xiaodong

2015-02-10

The design principles for naturally occurring biological materials have inspired us to develop next-generation engineering materials with remarkable performance. Nacre, commonly referred to as nature's armor, is renowned for its unusual combination of strength and toughness. Nature's wisdom in nacre resides in its elaborate structural design and the judicious placement of a unique organic biopolymer with intelligent deformation features. However, up to now, it is still a challenge to transcribe the biopolymer's deformation attributes into a stronger substitute in the design of new materials. In this study, we propose a new design strategy that employs shape memory alloy to transcribe the "J-curve" mechanical response and uniform molecular/atomic level deformation of the organic biopolymer in the design of high-performance hybrid materials. This design strategy is verified in a TiNi-Ti3Sn model material system. The model material demonstrates an exceptional combination of mechanical properties that are superior to other high-performance metal-based lamellar composites known to date. Our design strategy creates new opportunities for the development of high-performance bio-inspired materials.

Vagal Reactivity and Affective Adjustment in Infants during Interaction Challenges.

ERIC Educational Resources Information Center

Bazhenova, Olga V.; Plonskaia, Oxana; Porges, Stephen W.

2001-01-01

Evaluated respiratory sinus arrhythmia (RSA) and heart period in 5-month-olds during interaction challenges. Found that during object-mediated challenge, RSA increases were uniquely related to positive engagement. During person-mediated challenge, subjects showed more complex integration of autonomic and behavioral responses such that only infants…

Restaurant challenge offers healthful meal options and builds diabetes awareness.

PubMed

Blair, Angela M; Drass, Janice A; Stone, Marylou; Rhoades, Deborah; Baldwin, Susan A; Russ, Kelsey M

2011-01-01

The Frederick Restaurant Challenge is an innovative project based on a collaborative effort among community organizations and partners designed to offer delicious healthful meal options at local restaurants during the month of November for American Diabetes Month. Local restaurants were challenged to participate and submitted recipes for healthful meals to the Frederick County Diabetes Coalition for review by registered dietitians. Diners voted on meals to determine the challenge winner(s), and were eligible to win prizes as well. Publicity prior to and during the month was effective in creating positive news about healthful meals when eating out, raised awareness about diabetes, and provided restaurants with desirable advertising opportunities. Feedback from restaurants and diners was overwhelmingly positive. The purpose of this article is to describe this successful low-budget project to encourage its replication in local communities. The Frederick Restaurant Challenge proved to be a very successful, innovative, low-budget project that met its intended goals: to develop healthful meal options for people with diabetes (or for anyone wishing to eat healthier); to demonstrate that healthful food can taste delicious; and to encourage restaurants to continue offering healthful options on their menus beyond the challenge month. Community interventions such as the Frederick Restaurant Challenge offer unique and important strategies for affecting change and raising awareness not only for people with diabetes but also for the entire community.

Finite element analysis of wirelessly interrogated implantable bio-MEMS

NASA Astrophysics Data System (ADS)

Dissanayake, Don W.; Al-Sarawi, Said F.; Lu, Tien-Fu; Abbott, Derek

2008-12-01

Wirelessly interrogated bio-MEMS devices are becoming more popular due to many challenges, such as improving the diagnosis, monitoring, and patient wellbeing. The authors present here a passive, low power and small area device, which can be interrogated wirelessly using a uniquely coded signal for a secure and reliable operation. The proposed new approach relies on converting the interrogating coded signal to surface acoustic wave that is then correlated with an embedded code. The suggested method is implemented to operate a micropump, which consist of a specially designed corrugated microdiaphragm to modulate the fluid flow in microchannels. Finite Element Analysis of the micropump operation is presented and a performance was analysed. Design parameters of the diaphragm design were finetuned for optimal performance and different polymer based materials were used in various parts of the micropump to allow for better flexibility and high reliability.

Modernizing sports facilities

DOE Office of Scientific and Technical Information (OSTI.GOV)

Dustin, R.

Modernization and renovation of sports facilities challenge the design team to balance a number of requirements: spectator and owner expectations, existing building and site conditions, architectural layouts, code and legislation issues, time constraints and budget issues. System alternatives are evaluated and selected based on the relative priorities of these requirements. These priorities are unique to each project. At Alexander Memorial Coliseum, project schedules, construction funds and facility usage became the priorities. The ACC basketball schedule and arrival of the Centennial Olympics dictated the construction schedule. Initiation and success of the project depended on the commitment of the design team tomore » meet coliseum funding levels established three years ago. Analysis of facility usage and system alternative capabilities drove the design team to select a system that met the project requirements and will maximize the benefits to the owner and spectators for many years to come.« less

Orion Exploration Flight Test-l (EFT -1) Absolute Navigation Design

NASA Technical Reports Server (NTRS)

Sud, Jastesh; Gay, Robert; Holt, Greg; Zanetti, Renato

2014-01-01

Scheduled to launch in September 2014 atop a Delta IV Heavy from the Kennedy Space Center, the Orion Multi-Purpose-Crew-Vehicle (MPCV's) maiden flight dubbed "Exploration Flight Test -1" (EFT-1) intends to stress the system by placing the uncrewed vehicle on a high-energy parabolic trajectory replicating conditions similar to those that would be experienced when returning from an asteroid or a lunar mission. Unique challenges associated with designing the navigation system for EFT-1 are presented in the narrative with an emphasis on how redundancy and robustness influenced the architecture. Two Inertial Measurement Units (IMUs), one GPS receiver and three barometric altimeters (BALTs) comprise the navigation sensor suite. The sensor data is multiplexed using conventional integration techniques and the state estimate is refined by the GPS pseudorange and deltarange measurements in an Extended Kalman Filter (EKF) that employs the UDUT decomposition approach. The design is substantiated by simulation results to show the expected performance.

Major design issues of molten carbonate fuel cell power generation unit

DOE Office of Scientific and Technical Information (OSTI.GOV)

Chen, T.P.

1996-04-01

In addition to the stack, a fuel cell power generation unit requires fuel desulfurization and reforming, fuel and oxidant preheating, process heat removal, waste heat recovery, steam generation, oxidant supply, power conditioning, water supply and treatment, purge gas supply, instrument air supply, and system control. These support facilities add considerable cost and system complexity. Bechtel, as a system integrator of M-C Power`s molten carbonate fuel cell development team, has spent substantial effort to simplify and minimize these supporting facilities to meet cost and reliability goals for commercialization. Similiar to other fuels cells, MCFC faces design challenge of how to complymore » with codes and standards, achieve high efficiency and part load performance, and meanwhile minimize utility requirements, weight, plot area, and cost. However, MCFC has several unique design issues due to its high operating temperature, use of molten electrolyte, and the requirement of CO2 recycle.« less

Coproduction of healthcare service

PubMed Central

Batalden, Maren; Batalden, Paul; Margolis, Peter; Seid, Michael; Armstrong, Gail; Opipari-Arrigan, Lisa; Hartung, Hans

2016-01-01

Efforts to ensure effective participation of patients in healthcare are called by many names—patient centredness, patient engagement, patient experience. Improvement initiatives in this domain often resemble the efforts of manufacturers to engage consumers in designing and marketing products. Services, however, are fundamentally different than products; unlike goods, services are always ‘coproduced’. Failure to recognise this unique character of a service and its implications may limit our success in partnering with patients to improve health care. We trace a partial history of the coproduction concept, present a model of healthcare service coproduction and explore its application as a design principle in three healthcare service delivery innovations. We use the principle to examine the roles, relationships and aims of this interdependent work. We explore the principle's implications and challenges for health professional development, for service delivery system design and for understanding and measuring benefit in healthcare services. PMID:26376674

Reuse and Interoperability of Avionics for Space Systems

NASA Technical Reports Server (NTRS)

Hodson, Robert F.

2007-01-01

The space environment presents unique challenges for avionics. Launch survivability, thermal management, radiation protection, and other factors are important for successful space designs. Many existing avionics designs use custom hardware and software to meet the requirements of space systems. Although some space vendors have moved more towards a standard product line approach to avionics, the space industry still lacks similar standards and common practices for avionics development. This lack of commonality manifests itself in limited reuse and a lack of interoperability. To address NASA s need for interoperable avionics that facilitate reuse, several hardware and software approaches are discussed. Experiences with existing space boards and the application of terrestrial standards is outlined. Enhancements and extensions to these standards are considered. A modular stack-based approach to space avionics is presented. Software and reconfigurable logic cores are considered for extending interoperability and reuse. Finally, some of the issues associated with the design of reusable interoperable avionics are discussed.

Rational Design of Pathogen-Mimicking Amphiphilic Materials as Nanoadjuvants

NASA Astrophysics Data System (ADS)

Ulery, Bret D.; Petersen, Latrisha K.; Phanse, Yashdeep; Kong, Chang Sun; Broderick, Scott R.; Kumar, Devender; Ramer-Tait, Amanda E.; Carrillo-Conde, Brenda; Rajan, Krishna; Wannemuehler, Michael J.; Bellaire, Bryan H.; Metzger, Dennis W.; Narasimhan, Balaji

2011-12-01

An opportunity exists today for cross-cutting research utilizing advances in materials science, immunology, microbial pathogenesis, and computational analysis to effectively design the next generation of adjuvants and vaccines. This study integrates these advances into a bottom-up approach for the molecular design of nanoadjuvants capable of mimicking the immune response induced by a natural infection but without the toxic side effects. Biodegradable amphiphilic polyanhydrides possess the unique ability to mimic pathogens and pathogen associated molecular patterns with respect to persisting within and activating immune cells, respectively. The molecular properties responsible for the pathogen-mimicking abilities of these materials have been identified. The value of using polyanhydride nanovaccines was demonstrated by the induction of long-lived protection against a lethal challenge of Yersinia pestis following a single administration ten months earlier. This approach has the tantalizing potential to catalyze the development of next generation vaccines against diseases caused by emerging and re-emerging pathogens.

Design of a home-based adaptive mixed reality rehabilitation system for stroke survivors.

PubMed

Baran, Michael; Lehrer, Nicole; Siwiak, Diana; Chen, Yinpeng; Duff, Margaret; Ingalls, Todd; Rikakis, Thanassis

2011-01-01

This paper presents the design of a home-based adaptive mixed reality system (HAMRR) for upper extremity stroke rehabilitation. The goal of HAMRR is to help restore motor function to chronic stroke survivors by providing an engaging long-term reaching task therapy at home. The system uses an intelligent adaptation scheme to create a continuously challenging and unique multi-year therapy experience. The therapy is overseen by a physical therapist, but day-to-day use of the system can be independently set up and completed by a stroke survivor. The HAMMR system tracks movement of the wrist and torso and provides real-time, post-trial, and post-set feedback to encourage the stroke survivor to self-assess his or her movement and engage in active learning of new movement strategies. The HAMRR system consists of a custom table, chair, and media center, and is designed to easily integrate into any home.

Need for geriatric dentistry training programs in Iran.

PubMed

Mir, Arash Poorsattar Bejeh

2013-01-01

A shifting pattern from communicable diseases to the chronic noncommunicable diseases and increased life expectancy are being sensed throughout the world. Aged populations with multiple chronic diseases come up with their unique needs and require specific attention to be challenged by the health systems. Neglected orodental facts among the elders and the dearth of specific designated undergraduate and postgraduate courses of geriatric dentistry in Iran inevitably adversely affect the delivery of appropriate dental care service to elders by untrained dentists. In this article, a proposal for academic geriatric dentistry courses in Iran is introduced and highlighted with regards to elders' special needs.

Charge storage mechanism in nanoporous carbons and its consequence for electrical double layer capacitors.

PubMed

Simon, Patrice; Gogotsi, Yury

2010-07-28

Electrochemical capacitors, also known as supercapacitors, are energy storage devices that fill the gap between batteries and dielectric capacitors. Thanks to their unique features, they have a key role to play in energy storage and harvesting, acting as a complement to or even a replacement of batteries which has already been achieved in various applications. One of the challenges in the supercapacitor area is to increase their energy density. Some recent discoveries regarding ion adsorption in microporous carbon exhibiting pores in the nanometre range can help in designing the next generation of high-energy-density supercapacitors.

SBML and CellML translation in antimony and JSim.

PubMed

Smith, Lucian P; Butterworth, Erik; Bassingthwaighte, James B; Sauro, Herbert M

2014-04-01

The creation and exchange of biologically relevant models is of great interest to many researchers. When multiple standards are in use, models are more readily used and re-used if there exist robust translators between the various accepted formats. Antimony 2.4 and JSim 2.10 provide translation capabilities from their own formats to SBML and CellML. All provided unique challenges, stemming from differences in each format's inherent design, in addition to differences in functionality. Both programs are available under BSD licenses; Antimony from http://antimony.sourceforge.net/and JSim from http://physiome.org/jsim/. lpsmith@u.washington.edu.

Development of a Dynamically Scaled Generic Transport Model Testbed for Flight Research Experiments

NASA Technical Reports Server (NTRS)

Jordan, Thomas; Langford, William; Belcastro, Christine; Foster, John; Shah, Gautam; Howland, Gregory; Kidd, Reggie

2004-01-01

This paper details the design and development of the Airborne Subscale Transport Aircraft Research (AirSTAR) test-bed at NASA Langley Research Center (LaRC). The aircraft is a 5.5% dynamically scaled, remotely piloted, twin-turbine, swept wing, Generic Transport Model (GTM) which will be used to provide an experimental flight test capability for research experiments pertaining to dynamics modeling and control beyond the normal flight envelope. The unique design challenges arising from the dimensional, weight, dynamic (inertial), and actuator scaling requirements necessitated by the research community are described along with the specific telemetry and control issues associated with a remotely piloted subscale research aircraft. Development of the necessary operational infrastructure, including operational and safety procedures, test site identification, and research pilots is also discussed. The GTM is a unique vehicle that provides significant research capacity due to its scaling, data gathering, and control characteristics. By combining data from this testbed with full-scale flight and accident data, wind tunnel data, and simulation results, NASA will advance and validate control upset prevention and recovery technologies for transport aircraft, thereby reducing vehicle loss-of-control accidents resulting from adverse and upset conditions.

Rational Design of Au@Pt Multibranched Nanostructures as Bifunctional Nanozymes.

PubMed

Wu, Jiangjiexing; Qin, Kang; Yuan, Dan; Tan, Jun; Qin, Li; Zhang, Xuejin; Wei, Hui

2018-04-18

One of the current challenges in nanozyme-based nanotechnology is the utilization of multifunctionalities in one material. In this regard, Au@Pt nanoparticles (NPs) with excellent enzyme-mimicking activities due to the Pt shell and unique surface plasmon resonance features from the Au core have attracted enormous research interest. However, the unique surface plasmon resonance features from the Au core have not been widely utilized. The practical problem of the optical-damping nature of Pt hinders the research into the combination of Au@Pt NPs' enzyme-mimicking properties with their surface-enhanced Raman scattering (SERS) activities. Herein, we rationally tuned the Pt amount to achieve Au@Pt NPs with simultaneous plasmonic and enzyme-mimicking activities. The results showed that Au@Pt NPs with 2.5% Pt produced the highest Raman signal in 2 min, which benefited from the remarkably accelerated catalytic oxidation of 3,3',5,5'-tetramethylbenzidine with the decorated Pt and strong electric field retained from the Au core for SERS. This study not only demonstrates the great promise of combining bimetallic nanomaterials' multiple functionalities but also provides rational guidelines to design high-performance nanozymes for potential biomedical applications.

Optimization of NTP System Truss to Reduce Radiation Shield Mass

NASA Technical Reports Server (NTRS)

Scharber, Luke L.; Kharofa, Adam; Caffrey, Jarvis A.

2016-01-01

The benefits of nuclear thermal propulsion are numerous and relevant to the current NASA mission goals involving but not limited to the crewed missions to mars and the moon. They do however also present new and unique challenges to the design and logistics of launching/operating spacecraft. One of these challenges, relevant to this discussion, is the significant mass of the shielding which is required to ensure an acceptable radiation environment for the spacecraft and crew. Efforts to reduce shielding mass are difficult to accomplish from material and geometric design points of the shield itself, however by increasing the distance between the nuclear engines and the main body of the spacecraft the required mass of the shielding is lessened considerably. The mass can be reduced significantly per unit length, though any additional mass added by the structure to create this distance serves to offset those savings, thus the design of a lightweight structure is ideal. The challenges of designing the truss are bounded by several limiting factors including; the loading conditions, the capabilities of the launch vehicle, and achieving the ideal truss length when factoring for the overall mass reduced. Determining the overall set of mass values for a truss of varying length is difficult since to maintain an optimally designed truss the geometry of the truss or its members must change. Thus the relation between truss mass and length for these loading scenarios is not linear, and instead has relation determined by the truss design. In order to establish a mass versus length trend for various truss designs to compare with the mass saved from the shield versus length, optimization software was used to find optimal geometric properties that still met the design requirements at established lengths. By solving for optimal designs at various lengths, mass trends could be determined. The initial design findings show a clear benefit to extending the engines as far from the main structure of the spacecraft as the launch vehicle's payload volume would allow when comparing mass savings verse the additional structure.

Preliminary design of nine high speed civil transports

NASA Technical Reports Server (NTRS)

Sandlin, Doral; Vantriet, Robert; Soban, Dani; Hoang, TY

1992-01-01

Sixty senior design students at Cal Poly, SLO have completed a year-long project to design the next generation of High Speed Civil Transports (HSCT). The design process was divided up into three distinct phases. The first third of the project was devoted entirely to research into the special problems associated with an HSCT. These included economic viability, airport compatibility, high speed aerodynamics, sonic boom minimization, environmental impact, and structures and materials. The result of this research was the development of nine separate Requests for Proposal (RFP) that outlined reasonable yet challenging design criteria for the aircraft. All were designed to be technically feasible in the year 2015. The next phase of the project divided the sixty students into nine design groups. Each group, with its own RFP, completed a Class 1 preliminary design of an HSCT. The nine configurations varied from conventional double deltas to variable geometry wings to a pivoting oblique wing design. The final phase of the project included a more detailed Class 2 sizing as well as performance and stability and control analysis. Cal Poly, San Luis Obispo presents nine unique solutions to the same problem: that of designing an economically viable, environmentally acceptable, safe and comfortable supersonic transport.

Design, development and deployment of a Diabetes Research Registry to facilitate recruitment in clinical research.

PubMed

Tan, Meng H; Bernstein, Steven J; Gendler, Stephen; Hanauer, David; Herman, William H

2016-03-01

A major challenge in conducting clinical trials/studies is the timely recruitment of eligible subjects. Our aim is to develop a Diabetes Research Registry (DRR) to facilitate recruitment by matching potential subjects interested in research with approved clinical studies using study entry criteria abstracted from their electronic health records (EHR). A committee with expertise in diabetes, quality improvement, information technology, and informatics designed and developed the DRR. Using a hybrid approach, we identified and consented patients interested in research, abstracted their EHRs to assess common eligibility criteria, and contacted them about their interest in participating in specific studies. Investigators submit their requests with study entry criteria to the DRR which then provides a list of potential subjects who may be directly contacted for their study. The DRR meets all local, regional and federal regulatory requirements. After 5 years, the DRR has over 5000 registrants. About 30% have type 1 diabetes and 70% have type 2 diabetes. There are almost equal proportions of men and women. During this period, 31 unique clinical studies from 19 unique investigators requested lists of potential subjects for their studies. Eleven grant applications from 10 unique investigators used aggregated counts of potentially eligible subjects in their applications. The DRR matches potential subjects interested in research with approved clinical studies using study entry criteria abstracted from their EHR. By providing large lists of potentially eligible study subjects quickly, the DRR facilitated recruitment in 31 clinical studies. Copyright © 2016 Elsevier Inc. All rights reserved.

Reusable Solid Rocket Motor - Accomplishments, Lessons, and a Culture of Success

NASA Technical Reports Server (NTRS)

Moore, Dennis R.; Phelps, Willie J.

2011-01-01

The Reusable Solid Rocket Motor represents the largest solid rocket motor ever flown and the only human rated solid motor. Each Reusable Solid Rocket Motor (RSRM) provides approximately 3-million lb of thrust to lift the integrated Space Shuttle vehicle from the launch pad. The motors burn out approximately 2 minutes later, separate from the vehicle and are recovered and refurbished. The size of the motor and the need for high reliability were challenges. Thrust shaping, via shaping of the propellant grain, was needed to limit structural loads during ascent. The motor design evolved through several block upgrades to increase performance and to increase safety and reliability. A major redesign occurred after STS-51L with the Redesigned Solid Rocket Motor. Significant improvements in the joint sealing systems were added. Design improvements continued throughout the Program via block changes with a number of innovations including development of low temperature o-ring materials and incorporation of a unique carbon fiber rope thermal barrier material. Recovery of the motors and post flight inspection improved understanding of hardware performance, and led to key design improvements. Because of the multidecade program duration material obsolescence was addressed, and requalification of materials and vendors was sometimes needed. Thermal protection systems and ablatives were used to protect the motor cases and nozzle structures. Significant understanding of design and manufacturing features of the ablatives was developed during the program resulting in optimization of design features and processing parameters. The project advanced technology in eliminating ozone-depleting materials in manufacturing processes and the development of an asbestos-free case insulation. Manufacturing processes for the large motor components were unique and safety in the manufacturing environment was a special concern. Transportation and handling approaches were also needed for the large hardware segments. The reusable solid rocket motor achieved significant reliability via process control, ground test programs, and postflight assessment. Process control is mandatory for a solid rocket motor as an acceptance test of the delivered product is not feasible. Process control included process failure modes and effects analysis, statistical process control, witness panels, and process product integrity audits. Material controls and inspections were maintained throughout the sub tier vendors. Material fingerprinting was employed to assess any drift in delivered material properties. The RSRM maintained both full scale and sub-scale test articles. These enabled continuous improvement of design and evaluation of process control and material behavior. Additionally RSRM reliability was achieved through attention to detail in post flight assessment to observe any shift in performance. The postflight analysis and inspections provided invaluable reliability data as it enables observation of actual flight performance, most of which would not be available if the motors were not recovered. These unique challenges, features of the reusable solid rocket motor, materials and manufacturing issues, and design improvements will be discussed in the paper.

Applying health education theory to patient safety programs: three case studies.

PubMed

Gilkey, Melissa B; Earp, Jo Anne L; French, Elizabeth A

2008-04-01

Program planning for patient safety is challenging because intervention-oriented surveillance data are not yet widely available to those working in this nascent field. Even so, health educators are uniquely positioned to contribute to patient safety intervention efforts because their theoretical training provides them with a guide for designing and implementing prevention programs. This article demonstrates the utility of applying health education concepts from three prominent patient safety campaigns, including the concepts of risk perception, community participation, and social marketing. The application of these theoretical concepts to patient safety programs suggests that health educators possess a knowledge base and skill set highly relevant to patient safety and that their perspective should be increasingly brought to bear on the design and evaluation of interventions that aim to protect patients from preventable medical error.

Historical Perspectives and Guidelines for Botulinum Neurotoxin Subtype Nomenclature

PubMed Central

Peck, Michael W.; Smith, Theresa J.; Anniballi, Fabrizio; Austin, John W.; Bano, Luca; Bradshaw, Marite; Cuervo, Paula; Cheng, Luisa W.; Derman, Yagmur; Dorner, Brigitte G.; Fisher, Audrey; Hill, Karen K.; Kalb, Suzanne R.; Korkeala, Hannu; Lindström, Miia; Lista, Florigio; Lúquez, Carolina; Mazuet, Christelle; Pirazzini, Marco; Popoff, Michel R.; Rossetto, Ornella; Rummel, Andreas; Sesardic, Dorothea; Singh, Bal Ram; Stringer, Sandra C.

2017-01-01

Botulinum neurotoxins are diverse proteins. They are currently represented by at least seven serotypes and more than 40 subtypes. New clostridial strains that produce novel neurotoxin variants are being identified with increasing frequency, which presents challenges when organizing the nomenclature surrounding these neurotoxins. Worldwide, researchers are faced with the possibility that toxins having identical sequences may be given different designations or novel toxins having unique sequences may be given the same designations on publication. In order to minimize these problems, an ad hoc committee consisting of over 20 researchers in the field of botulinum neurotoxin research was convened to discuss the clarification of the issues involved in botulinum neurotoxin nomenclature. This publication presents a historical overview of the issues and provides guidelines for botulinum neurotoxin subtype nomenclature in the future. PMID:28106761

Rendezvous and Proximity Operations of the Space Shuttle

NASA Technical Reports Server (NTRS)

Goodman, John L.

2005-01-01

Space Shuttle rendezous missions presented unique challenges that were not fully recognized when the Shuttle was designed. Rendezvous targets could be passive (i.e., no lights or transponders), and not designed to facilitate Shuttle rendezvous, proximity operations and retrieval. Shuttle reaction control system jet plume impingement on target spacecraft presented induced dynamics, structural loading and contamination concerns. These issues, along with limited forward reaction control system propellant, drove a change from the Gemimi/Apollo coelliptic profile heritage to a stable orbit profile, and the development of new proximity operations techniques. Multiple scientific and on-orbit servicing missions and crew exchange, assembly and replinishment flights to Mir and to the International Space Station drove further profile and piloting technique changes, including new relative navigation sensors and new computer generated piloting cues.

Application of computational methods to the design and characterisation of porous molecular materials.

PubMed

Evans, Jack D; Jelfs, Kim E; Day, Graeme M; Doonan, Christian J

2017-06-06

Composed from discrete units, porous molecular materials (PMMs) possess unique properties not observed for conventional, extended, solids, such as solution processibility and permanent porosity in the liquid phase. However, identifying the origin of porosity is not a trivial process, especially for amorphous or liquid phases. Furthermore, the assembly of molecular components is typically governed by a subtle balance of weak intermolecular forces that makes structure prediction challenging. Accordingly, in this review we canvass the crucial role of molecular simulations in the characterisation and design of PMMs. We will outline strategies for modelling porosity in crystalline, amorphous and liquid phases and also describe the state-of-the-art methods used for high-throughput screening of large datasets to identify materials that exhibit novel performance characteristics.

Historical Perspectives and Guidelines for Botulinum Neurotoxin Subtype Nomenclature.

PubMed

Peck, Michael W; Smith, Theresa J; Anniballi, Fabrizio; Austin, John W; Bano, Luca; Bradshaw, Marite; Cuervo, Paula; Cheng, Luisa W; Derman, Yagmur; Dorner, Brigitte G; Fisher, Audrey; Hill, Karen K; Kalb, Suzanne R; Korkeala, Hannu; Lindström, Miia; Lista, Florigio; Lúquez, Carolina; Mazuet, Christelle; Pirazzini, Marco; Popoff, Michel R; Rossetto, Ornella; Rummel, Andreas; Sesardic, Dorothea; Singh, Bal Ram; Stringer, Sandra C

2017-01-18

Botulinum neurotoxins are diverse proteins. They are currently represented by at least seven serotypes and more than 40 subtypes. New clostridial strains that produce novel neurotoxin variants are being identified with increasing frequency, which presents challenges when organizing the nomenclature surrounding these neurotoxins. Worldwide, researchers are faced with the possibility that toxins having identical sequences may be given different designations or novel toxins having unique sequences may be given the same designations on publication. In order to minimize these problems, an ad hoc committee consisting of over 20 researchers in the field of botulinum neurotoxin research was convened to discuss the clarification of the issues involved in botulinum neurotoxin nomenclature. This publication presents a historical overview of the issues and provides guidelines for botulinum neurotoxin subtype nomenclature in the future.

Multiscale Poly-(ϵ-caprolactone) Scaffold Mimicking Nonlinearity in Tendon Tissue Mechanics

PubMed Central

Banik, Brittany L.; Lewis, Gregory S.; Brown, Justin L.

2016-01-01

Regenerative medicine plays a critical role in the future of medicine. However, challenges remain to balance stem cells, biomaterial scaffolds, and biochemical factors to create successful and effective scaffold designs. This project analyzes scaffold architecture with respect to mechanical capability and preliminary mesenchymal stem cell response for tendon regeneration. An electrospun fiber scaffold with tailorable properties based on a “Chinese-fingertrap” design is presented. The unique criss-crossed fiber structures demonstrate non-linear mechanical response similar to that observed in native tendon. Mechanical testing revealed that optimizing the fiber orientation resulted in the characteristic “S”-shaped curve, demonstrating a toe region and linear elastic region. This project has promising research potential across various disciplines: vascular engineering, nerve regeneration, and ligament and tendon tissue engineering. PMID:27141530

Oregon Sustainability Center: Weighing Approaches to Net Zero

DOE Office of Scientific and Technical Information (OSTI.GOV)

Regnier, Cindy; Robinson, Alastair; Settlemyre, Kevin

2013-10-01

The Oregon Sustainability Center (OSC) was to represent a unique public/private partnership between the city of Portland, Oregon, state government, higher education, non-profit organizations, and the business community. A unique group of stakeholders partnered with the U.S. Department of Energy (DOE) technical expert team (TET) to collaboratively identify, analyze, and evaluate solutions to enable the OSC to become a high-performance sustainability landmark in downtown Portland. The goal was to build a new, low-energy mixed-use urban high-rise that consumes at least 50 percent less energy than requirements set by Energy Standard 90.1-2007 of the American Society of Heating, Refrigerating, and Air-Conditioningmore » Engineers (ASHRAE), the American National Standards Institute (ANSI), and the Illuminating Engineering Society of America (IESNA) as part of DOE’s Commercial Building Partnerships (CBP) program.1 In addition, the building design was to incorporate renewable energy sources that would account for the remaining energy consumption, resulting in a net zero building. The challenge for the CBP DOE technical team was to evaluate factors of risk and components of resiliency in the current net zero energy design and analyze that design to see if the same high performance could be achieved by alternative measures at lower costs. In addition, the team was to use a “lens of scalability” to assess whether or not the strategies could be applied to more projects. However, a key component of the required project funding did not pass, and therefore this innovative building design was discontinued while it was in the design development stage.« less

Challenges and Opportunities for Small-Molecule Fluorescent Probes in Redox Biology Applications.

PubMed

Jiang, Xiqian; Wang, Lingfei; Carroll, Shaina L; Chen, Jianwei; Wang, Meng C; Wang, Jin

2018-02-16

The concentrations of reactive oxygen/nitrogen species (ROS/RNS) are critical to various biochemical processes. Small-molecule fluorescent probes have been widely used to detect and/or quantify ROS/RNS in many redox biology studies and serve as an important complementary to protein-based sensors with unique applications. Recent Advances: New sensing reactions have emerged in probe development, allowing more selective and quantitative detection of ROS/RNS, especially in live cells. Improvements have been made in sensing reactions, fluorophores, and bioavailability of probe molecules. In this review, we will not only summarize redox-related small-molecule fluorescent probes but also lay out the challenges of designing probes to help redox biologists independently evaluate the quality of reported small-molecule fluorescent probes, especially in the chemistry literature. We specifically highlight the advantages of reversibility in sensing reactions and its applications in ratiometric probe design for quantitative measurements in living cells. In addition, we compare the advantages and disadvantages of small-molecule probes and protein-based probes. The low physiological relevant concentrations of most ROS/RNS call for new sensing reactions with better selectivity, kinetics, and reversibility; fluorophores with high quantum yield, wide wavelength coverage, and Stokes shifts; and structural design with good aqueous solubility, membrane permeability, low protein interference, and organelle specificity. Antioxid. Redox Signal. 00, 000-000.

Observation management challenges of the Square Kilometre Array

NASA Astrophysics Data System (ADS)

Bridger, Alan; Williams, Stewart J.; Nicol, Mark; Klaassen, Pamela; Thompson, Roger S.; Knapic, Cristina; Jerse, Giovanna; Orlati, Andrea; Messina, Marco; Valame, Snehal

2016-07-01

The Square Kilometre Array (SKA) will be the world's most advanced radio telescope, designed to explore some of the biggest questions in astronomy today, such as the epoch of re-ionization, the nature of gravity and the origins of cosmic magnetism. SKA1, the first phase of SKA construction, is currently being designed by a large team of experts world-wide. SKA1 comprises two telescopes: a 200-element dish interferometer in South Africa and a 130000-element dipole antenna aperture array in Australia. To enable the ground-breaking science of the SKA an advanced Observation Management system is required to support both the needs of the astronomical community users and the SKA Observatory staff. This system will ensure that the SKA realises its scientiffc aims and achieves optimal scientific throughput. This paper provides an overview of the design of the system that will accept proposals from SKA users, and result in the execution of the scripts that will obtain science data, taking in the stages of detailed preparation, planning and scheduling of the observations and onwards tracking. It describes the unique challenges of the differing requirements of two telescopes, one of which is very much a software telescope, including the need to schedule the data processing as well as the acquisition, and to react to both internally and externally discovered transient events. The scheduling of multiple parallel sub-array use is covered, along with the need to handle commensal observing - using the same data stream to satisfy the science goals of more than one project simultaneously. An international team from academia and industry, drawing on expertise and experience from previous telescope projects, the virtual observatory and comparable problems in industry, has been assembled to design the solution to this challenging but exciting problem.

Overview of the Altair Lunar Lander Thermal Control System Design and the Impacts of Global Access

NASA Technical Reports Server (NTRS)

Stephan, Ryan A.

2011-01-01

NASA's Constellation Program (CxP) was developed to successfully return humans to the Lunar surface prior to 2020. The CxP included several different project offices including Altair, which was planned to be the next generation Lunar Lander. The Altair missions were architected to be quite different than the Lunar missions accomplished during the Apollo era. These differences resulted in a significantly dissimilar Thermal Control System (TCS) design. The current paper will summarize the Altair mission architecture and the various operational phases associated with the planned mission. In addition, the derived thermal requirements and the TCS designed to meet these unique and challenging thermal requirements will be presented. During the past year, the design team has focused on developing a vehicle architecture capable of accessing the entire Lunar surface. Due to the widely varying Lunar thermal environment, this global access requirement resulted in major changes to the thermal control system architecture. These changes, and the rationale behind the changes, will be detailed throughout the current paper.

Shuttle Radar Topography Mission (SRTM) Flight System Design and Operations Overview

NASA Technical Reports Server (NTRS)

Shen, Yuhsyen; Shaffer, Scott J.; Jordan, Rolando L.

2000-01-01

This paper provides an overview of the Shuttle Radar Topography Mission (SRTM), with emphasis on flight system implementation and mission operations from systems engineering perspective. Successfully flown in February, 2000, the SRTM's primary payload consists of several subsystems to form the first spaceborne dual-frequency (C-band and X-band) fixed baseline interferometric synthetic aperture radar (InSAR) system, with the mission objective to acquire data sets over 80% of Earth's landmass for height reconstruction. The paper provides system architecture, unique design features, engineering budgets, design verification, in-flight checkout and data acquisition of the SRTM payload, in particular for the C-band system. Mission operation and post-mission data processing activities are also presented. The complexity of the SRTM as a system, the ambitious mission objective, the demanding requirements and the high interdependency between multi-disciplined subsystems posed many challenges. The engineering experience and the insight thus gained have important implications for future spaceborne interferometric SAR mission design and implementation.

Closed Loop System Identification with Genetic Algorithms

NASA Technical Reports Server (NTRS)

Whorton, Mark S.

2004-01-01

High performance control design for a flexible space structure is challenging since high fidelity plant models are di.cult to obtain a priori. Uncertainty in the control design models typically require a very robust, low performance control design which must be tuned on-orbit to achieve the required performance. Closed loop system identi.cation is often required to obtain a multivariable open loop plant model based on closed-loop response data. In order to provide an accurate initial plant model to guarantee convergence for standard local optimization methods, this paper presents a global parameter optimization method using genetic algorithms. A minimal representation of the state space dynamics is employed to mitigate the non-uniqueness and over-parameterization of general state space realizations. This control-relevant system identi.cation procedure stresses the joint nature of the system identi.cation and control design problem by seeking to obtain a model that minimizes the di.erence between the predicted and actual closed-loop performance.

Solid-phase synthesis and screening of N-acylated polyamine (NAPA) combinatorial libraries for protein binding.

PubMed

Iera, Jaclyn A; Jenkins, Lisa M Miller; Kajiyama, Hiroshi; Kopp, Jeffrey B; Appella, Daniel H

2010-11-15

Inhibitors for protein-protein interactions are challenging to design, in part due to the unique and complex architectures of each protein's interaction domain. Most approaches to develop inhibitors for these interactions rely on rational design, which requires prior structural knowledge of the target and its ligands. In the absence of structural information, a combinatorial approach may be the best alternative to finding inhibitors of a protein-protein interaction. Current chemical libraries, however, consist mostly of molecules designed to inhibit enzymes. In this manuscript, we report the synthesis and screening of a library based on an N-acylated polyamine (NAPA) scaffold that we designed to have specific molecular features necessary to inhibit protein-protein interactions. Screens of the library identified a member with favorable binding properties to the HIV viral protein R (Vpr), a regulatory protein from HIV, that is involved in numerous interactions with other proteins critical for viral replication. Published by Elsevier Ltd.

Challenges in conducting psychiatry studies in India

PubMed Central

Kharawala, Saifuddin; Dalal, Jeroze

2011-01-01

A large number of psychiatry studies are conducted in India. Psychiatry studies are complex and present unique challenges in the Indian setting. Ethical issues pertaining to the risk of worsening of illness, use of placebo and validity of informed consents are commonly faced. Site selection can be difficult due to the relative paucity of ICH-GCP (International Conference on Harmonisation - Good Clinical Practice) trained psychiatry investigators in India. Recruitment can be challenging due to issues such as strict eligibility criteria, (lack of) availability of caregiver, illness-related considerations, etc. Assessment of the consent capacity of patients is not simple, while structured assessments are not commonly employed. As the illness fluctuates, the consent capacity may change, thus requiring continued assessment of consent capacity. Study patients run the risk of worsening of illness and suicide due to exposure to inactive treatments; this risk is counterbalanced by use of appropriate study designs, as well as the indirect psychotherapeutic support received. Psychiatry studies are associated with a high placebo response. This necessitates conduct of placebo-controlled studies despite the attendant difficulties. Also, the high placebo response is often the cause of failed trials. Rating scales are essential for assessment of drug response. Some rating instruments as well as some rater training procedures may not be suitable for the Indian setting. Technological advancements may increase the procedural complexity but improve the quality of ratings. Psychiatry studies present monitors and auditors with unique scenarios too. Utilization of psychiatry specific training and expertise is recommended to ensure successful conduct of these studies in India. PMID:21584176

Motivational techniques to improve self-care in hemophilia: the need to support autonomy in children.

PubMed

Bérubé, Sarah; Mouillard, Florine; Amesse, Claudine; Sultan, Serge

2016-01-11

In pediatric hemophilia, caregivers are facing unique challenges to adherence and self-care in children and adolescents with hemophilia. Hemophilia treatment requires adequate prophylaxis and on-demand treatment, as well as a clear behavioral strategy to limit risk-taking in terms of physical exercise and diet. Medication adherence rates of hemophilia patients have been reported to decrease during late childhood and adolescence. In the developing child, moving safely from parent-care to self-care is one of the greatest challenges of integrative care within this domain. There is a clear need for initiatives designed to increase an individual's motivation for treatment and self-care activities. Among motivational approaches, the self-determination perspective offers a useful framework to explain how the transition to self-care can be facilitated. We discuss how motivation regarding hemophilia treatment may be increased through parental autonomy support and we offer examples of applied communication techniques to facilitate autonomy-supportive caregiving. Although it has not yet been tested in the context of hemophilia, these communication techniques could potentially help caregivers promote adherence and self-care in children. Confronted by unique challenges to adherence and self-care, caregivers of children with hemophilia should move from an exclusive focus on illness-management education to an integrative strategy, including motivation-enhancing communication. The self-determination perspective provides important proximal objectives (e.g. autonomy support) to maintain optimal adherence in adolescents as they move from parent-care to self-care. Future research initiatives should address the practice of these communication techniques and evaluate them in the context of hemophilia.

Planning strategies for the avoidance of pitfalls in intervention research.

PubMed

Pruitt, R H; Privette, A B

2001-08-01

With the exception of large clinical trials, few studies in nursing and other social sciences test interventions. The discipline of nursing needs to maintain a full range of research designs for continued knowledge development. Intervention research presents unique opportunities and challenges for the novice as well as the seasoned researcher. Some of these methodological challenges include the complex nature of human subjects and interventions, including many factors that interfere with the study variables. Preliminary studies often reveal challenges that may not always be predicted or reflected in research texts. These challenges may be as important as the study results for success in future research efforts. Difficulties encountered in intervention research and suggested strategies for maintaining the integrity of the study are addressed. These challenges include maintaining an adequate sample size, intervention demands, measuring variables, timing issues, and experiencing unexpected events. Strategies presented include the importance of extensive planning, minimizing subject expectations and rewarding efforts, attention to control group members, incorporating retention strategies, expanding knowledge of variables and the study population, preliminary studies as well as anticipating unexpected events. The need for enhanced communication among nurse researchers, educators and clinicians is addressed. In the current health care arena, nurse researchers must understand organizational dynamics and marketing strategies. Collaborative research efforts can increase the visibility of nursing research as well as funding opportunities.

Implementation of the Integrated Management of Childhood Illnesses strategy: challenges and recommendations in Botswana

PubMed Central

Mupara, Lucia U.; Lubbe, Johanna C.

2016-01-01

Background Under-five mortality has been a major public health challenge from time immemorial. In response to this challenge, the World Health Organization and the United Nations Children's Fund developed the Integrated Management of Childhood Illnesses (IMCI) strategy and presented it to the whole world as a key approach to reduce child morbidity and mortality. Botswana started to implement the IMCI strategy in 1998. Reductions in the under-five mortality rate (U5MR) have been documented, although the reduction is not on par with the expected Millennium Development Goal 4 predictions. Design A quantitative study was done to identify the problems IMCI implementers face when tending children under 5 years in the Gaborone Health District of Botswana. The study population was made up of all the IMCI-trained and registered nurses, and systematic sampling was used to randomly select study participants. Questionnaires were used to collect data. Results The study findings indicated challenges related to low training coverage, health systems, and the unique features of the IMCI strategy. Conclusions The comprehensive implementation of the IMCI strategy has the potential to significantly influence the U5MR in Botswana. PMID:26899774

Life Support Requirements and Challenges for NASA's Constellation Program

NASA Technical Reports Server (NTRS)

Carasquillo, Robyn

2007-01-01

NASA's Constellation Program, which includes the mission objectives of establishing a permanently-manned lunar Outpost, and the exploration of Mars, poses new and unique challenges for human life support systems that will require solutions beyond the Shuttle and International Space Station state of the art systems. In particular, the requirement to support crews for 210 days duration at the lunar outpost with limited resource resupply capability wilt require closed-loop regenerative life support systems with minimal expendables. Planetary environmental conditions such as lunar dust and extreme temperatures, as well as the capability to support frequent and extended-duration EVA's will be particularly challenging. This presentation will summarize the key program and mission life support requirements for the Constellation Program and the unique challenges they present for technology and architecture development.

Effective, clinically feasible and sustainable: Key design features of psycho-educational and supportive care interventions to promote individualised self-management in cancer care.

PubMed

Schofield, Penelope; Chambers, Suzanne

2015-05-01

As the global burden of cancer increases healthcare services will face increasing challenges in meet the complex needs of these patients, their families and the communities in which they live. This raises the question of how to meet patient need where direct clinical contact may be constrained or not readily available. Patients and families require resources and skills to manage their illness outside of the hospital setting within their own communities. To propose a framework for the development and delivery of psycho-educational and supportive care interventions drawing on theoretical principles of behaviour change and evidence-based interventions, and based on extensive experience in developing and testing complex interventions in oncology. At the core of this intervention framework are considerations of efficiency: interventions are designed to cater for individuals' unique needs; to place minimal demands on the health system infrastructure and to be rapidly disseminated into usual care if successful. There are seven key features: 1) Targeting cancer type and stage; 2) Tailoring to unique individual needs; 3) Promotion of patient self-management of their disease and treatment side effects; 4) Efficient delivery of the intervention; 5) Training and adherence to protocol; 6) Ensuring the intervention is evidence-based; 7) Confirming stakeholder acceptability of the intervention. A case study of a randomised controlled trial which tested psycho-educational oncology interventions using this framework is presented. These interventions were designed to cater for individuals' unique needs and promote self-management while placing minimal demands on the acute health care setting. Innovative ways to realise the potentially major impact that psycho-educational and supportive care interventions can have on psychological morbidity, coping, symptoms and quality of life in serious and chronic illness are needed. This framework, which is driven by theory, evidence, and experience, is designed to ensure that interventions are effective, clinically feasible and sustainable.

New Strategies and Challenges in Lung Proteomics and Metabolomics. An Official American Thoracic Society Workshop Report.

PubMed

Bowler, Russell P; Wendt, Chris H; Fessler, Michael B; Foster, Matthew W; Kelly, Rachel S; Lasky-Su, Jessica; Rogers, Angela J; Stringer, Kathleen A; Winston, Brent W

2017-12-01

This document presents the proceedings from the workshop entitled, "New Strategies and Challenges in Lung Proteomics and Metabolomics" held February 4th-5th, 2016, in Denver, Colorado. It was sponsored by the National Heart Lung Blood Institute, the American Thoracic Society, the Colorado Biological Mass Spectrometry Society, and National Jewish Health. The goal of this workshop was to convene, for the first time, relevant experts in lung proteomics and metabolomics to discuss and overcome specific challenges in these fields that are unique to the lung. The main objectives of this workshop were to identify, review, and/or understand: (1) emerging technologies in metabolomics and proteomics as applied to the study of the lung; (2) the unique composition and challenges of lung-specific biological specimens for metabolomic and proteomic analysis; (3) the diverse informatics approaches and databases unique to metabolomics and proteomics, with special emphasis on the lung; (4) integrative platforms across genetic and genomic databases that can be applied to lung-related metabolomic and proteomic studies; and (5) the clinical applications of proteomics and metabolomics. The major findings and conclusions of this workshop are summarized at the end of the report, and outline the progress and challenges that face these rapidly advancing fields.

Biodegradable nanoparticles for intracellular delivery of antimicrobial agents.

PubMed

Xie, Shuyu; Tao, Yanfei; Pan, Yuanhu; Qu, Wei; Cheng, Guyue; Huang, Lingli; Chen, Dongmei; Wang, Xu; Liu, Zhenli; Yuan, Zonghui

2014-08-10

Biodegradable nanoparticles have emerged as a promising strategy for ferrying antimicrobial agents into specific cells due to their unique properties. This review discusses the current progress and challenges of biodegradable nanoparticles for intracellular antimicrobial delivery to understand design principles for the development of ideal nanocarriers. The intracellular delivery performances of biodegradable nanoparticles for diverse antimicrobial agents are first summarized. Second, the cellular internalization and intracellular trafficking, degradation and release kinetics of nanoparticles as well as their relation with intracellular delivery of encapsulated antimicrobial agents are provided. Third, the influences of nanoparticle properties on the cellular internalization and intracellular fate of nanoparticles and their payload antimicrobial agents are discussed. Finally, the challenges and perspectives of nanoparticles for intracellular delivery of antimicrobial agents are addressed. The review will be helpful to the scientists who are interested in searching for more efficient nanosystem strategies for intracellular delivery of antimicrobial agents. Copyright © 2014 Elsevier B.V. All rights reserved.

Composites of Polymer Hydrogels and Nanoparticulate Systems for Biomedical and Pharmaceutical Applications

PubMed Central

Zhao, Fuli; Yao, Dan; Guo, Ruiwei; Deng, Liandong; Dong, Anjie; Zhang, Jianhua

2015-01-01

Due to their unique structures and properties, three-dimensional hydrogels and nanostructured particles have been widely studied and shown a very high potential for medical, therapeutic and diagnostic applications. However, hydrogels and nanoparticulate systems have respective disadvantages that limit their widespread applications. Recently, the incorporation of nanostructured fillers into hydrogels has been developed as an innovative means for the creation of novel materials with diverse functionality in order to meet new challenges. In this review, the fundamentals of hydrogels and nanoparticles (NPs) were briefly discussed, and then we comprehensively summarized recent advances in the design, synthesis, functionalization and application of nanocomposite hydrogels with enhanced mechanical, biological and physicochemical properties. Moreover, the current challenges and future opportunities for the use of these promising materials in the biomedical sector, especially the nanocomposite hydrogels produced from hydrogels and polymeric NPs, are discussed. PMID:28347111

Electronic cigarette explosions involving the oral cavity.

PubMed

Harrison, Rebecca; Hicklin, David

2016-11-01

The use of electronic cigarettes (e-cigarettes) is a rapidly growing trend throughout the United States. E-cigarettes have been linked to the risk of causing explosion and fire. Data are limited on the associated health hazards of e-cigarette use, particularly long-term effects, and available information often presents conflicting conclusions. In addition, an e-cigarette explosion and fire can pose a unique treatment challenge to the dental care provider because the oral cavity may be affected heavily. In this particular case, the patient's injuries included intraoral burns, luxation injuries, and alveolar fractures. This case report aims to help clinicians gain an increased knowledge about e-cigarette design, use, and risks; discuss the risk of spontaneous failure and explosion of e-cigarettes with patients; and understand the treatment challenges posed by an e-cigarette explosion. Copyright © 2016 American Dental Association. Published by Elsevier Inc. All rights reserved.

Changing roles of universities in the era of SDGs: rising up to the global challenge through institutionalising partnerships with governments and communities.

PubMed

El-Jardali, Fadi; Ataya, Nour; Fadlallah, Racha

2018-05-09

The 2030 Agenda for Sustainable Development covers a wide range of interrelated goals, including poverty eradication and economic growth, social inclusion, environmental sustainability and peace for all people by 2030. Policy decisions to meet the Sustainable Development Goals (SDGs) need to be informed by policy-relevant evidence co-designed and co-produced with the pertinent stakeholders, taking into consideration local and political contexts. Universities are uniquely placed to lead the cross-sectoral implementation of the SDGs and advance the 2030 agenda. This commentary provides the case for building, strengthening and institutionalising university partnerships with governments and communities to achieve the SDGs. The authors call for a change in mindsets and culture in both academia and government, and invite both parties to start the dialogue if we are to rise up to the global challenge.

Material Innovation in Advancing Organometal Halide Perovskite Functionality.

PubMed

Zheng, Fan; Saldana-Greco, Diomedes; Liu, Shi; Rappe, Andrew M

2015-12-03

Organometal halide perovskites (OMHPs) have garnered much attention recently for their unprecedented rate of increasing power conversion efficiency (PCE), positioning them as a promising basis for the next-generation photovoltaic devices. However, the gap between the rapid increasing PCE and the incomplete understanding of the structure-property-performance relationship prevents the realization of the true potential of OMHPs. This Perspective aims to provide a concise overview of the current status of OMHP research, highlighting the unique properties of OMHPs that are critical for solar applications but still not adequately explained. Stability and performance challenges of OMHP solar cells are discussed, calling upon combined experimental and theoretical efforts to address these challenges for pioneering commercialization of OMHP solar cells. Various material innovation strategies for improving the performance and stability of OMHPs are surveyed, showing that the OMHP architecture can serve as a promising and robust platform for the design and optimization of materials with desired functionalities.

Landscape and climate science and scenarios for Florida

USGS Publications Warehouse

Terando, Adam; Traxler, Steve; Collazo, Jaime

2014-01-01

The Peninsular Florida Landscape Conservation Cooperative (PFLCC) is part of a network of 22 Landscape Conservation Cooperatives (LCCs) that extend from Alaska to the Caribbean. LCCs are regional-applied conservation-science partnerships among Federal agencies, regional organizations, States, tribes, nongovernmental organizations (NGOs), private stakeholders, universities, and other entities within a geographic area. The goal of these conservation-science partnerships is to help inform managers and decision makers at a landscape scale to further the principles of adaptive management and strategic habitat conservation. A major focus for LCCs is to help conservation managers and decision makers respond to large-scale ecosystem and habitat stressors, such as climate change, habitat fragmentation, invasive species, and water scarcity. The purpose of the PFLCC is to facilitate planning, design, and implementation of conservation strategies for fish and wildlife species at the landscape level using the adaptive management framework of strategic habitat conservation—integrating planning, design, delivery, and evaluation. Florida faces a set of unique challenges when responding to regional and global stressors because of its unique ecosystems and assemblages of species, its geographic location at the crossroads of temperate and tropical climates, and its exposure to both rapid urbanization and rising sea levels as the climate warms. In response to these challenges, several landscape-scale science projects were initiated with the goal of informing decision makers about how potential changes in climate and the built environment could impact habitats and ecosystems of concern in Florida and the Southeast United States. In June 2012, the PFLCC, North Carolina State University, convened a workshop at the U.S. Geological Survey (USGS) Coastal and Marine Science Center in St. Petersburg to assess the results of these integrated assessments and to foster an open dialogue about science gaps and future research needs.

Conceptual Drivers for an Exploration Medical System

NASA Technical Reports Server (NTRS)

Antonsen, Erik; Hanson, Andrea; Shah, Ronak; Reed, Rebekah; Canga, Michael

2016-01-01

Interplanetary spaceflight, such as NASA's proposed three-year mission to Mars, provides unique and novel challenges when compared with human spaceflight to date. Extended distance and multi-year missions introduce new elements of operational complexity and additional risk. These elements include: inability to resupply medications and consumables, inability to evacuate injured or ill crew, uncharted psychosocial conditions, and communication delays that create a requirement for some level of autonomous medical capability. Because of these unique challenges, the approaches used in prior programs have limited application to a Mars mission. On a Mars mission, resource limitations will significantly constrain available medical capabilities, and require a paradigm shift in the approach to medical system design and risk mitigation for crew health. To respond to this need for a new paradigm, the Exploration Medical Capability (ExMC) Element is assessing each Mars mission phase-transit, surface stay, rendezvous, extravehicular activity, and return-to identify and prioritize medical needs for the journey beyond low Earth orbit (LEO). ExMC is addressing both planned medical operations, and unplanned contingency medical operations that meld clinical needs and research needs into a single system. This assessment is being used to derive a gap analysis and studies to support meaningful medical capabilities trades. These trades, in turn, allow the exploration medical system design to proceed from both a mission centric and ethics-based approach, and to manage the risks associated with the medical limitations inherent in an exploration class mission. This paper outlines the conceptual drivers used to derive medical system and vehicle needs from an integrated vision of how medical care will be provided within this paradigm. Keywords: (Max 6 keywords: exploration, medicine, spaceflight, Mars, research, NASA)

D-amino acid-containing supramolecular nanofibers for potential cancer therapeutics.

PubMed

Wang, Huaimin; Feng, Zhaoqianqi; Xu, Bing

2017-02-01

Nanostructures formed by peptides that self-assemble in water through non-covalent interactions have attracted considerable attention because peptides possess several unique advantages, such as modular design and easiness of synthesis, convenient modification with known functional motifs, good biocompatibility, low immunogenicity and toxicity, inherent biodegradability, and fast responses to a wide range of external stimuli. After about two decades of development, peptide-based supramolecular nanostructures have already shown great potentials in the fields of biomedicine. Among a range of biomedical applications, using such nanostructures for cancer therapy has attracted increased interests since cancer remains the major threat for human health. Comparing with L-peptides, nanostructures containing peptides made of D-amino acid (i.e., D-peptides) bear a unique advantage, biostability (i.e., resistance towards most of endogenous enzymes). The exploration of nanostructures containing D-amino acids, especially their biomedical applications, is still in its infancy. Herein we review the recent progress of D-amino acid-containing supramolecular nanofibers as an emerging class of biomaterials that exhibit unique features for the development of cancer therapeutics. In addition, we give a brief perspective about the challenges and promises in this research direction. Copyright © 2016 Elsevier B.V. All rights reserved.

Social Interaction Needs and Entertainment Approaches to Pregnancy Well-Being in mHealth Technology Design for Low-Income Transmigrant Women: Qualitative Codesign Study

PubMed Central

2018-01-01

Background Low-income Caribbean transmigrant women face unique health challenges during pregnancy that set forth multidimensional implications for the design of mobile health (mHealth). Acknowledgment of the unique health needs of low-income Caribbean immigrant women in the United States and what that entails regarding technology design remains rarely examined in the literature of mHealth technologies. Objective The goal of this study was to reveal the needs and gaps in mHealth interventions for pregnant immigrant women not yet realized in this field. These understandings reveal design opportunities for mHealth. Methods The use of the qualitative participatory action research approach of codesign workshops in this study resulted in design solutions by the participants after reflecting on their earlier focus group discussions. The highlights are not the resulting designs per se but rather the inferences derived from the researcher reflecting on these designs. Results The designs exposed two themes relevant to this paper. First, the participants desired the inclusion and rebuilding of social and organizational relationships in mHealth. The resulting designs formulate an understanding of the women’s health-related social support needs and how technology can facilitate them. Second, the participants wanted entertainment with an element of social participation incorporated in mHealth pregnancy management interventions. This brings attention to the role entertainment can add to the impact mHealth can deliver for pregnancy well-being. Conclusions The study concluded with an examination of social and entertainment design implications that reveal pregnant immigrant women’s virtual health-related sharing habits, choice of sharing interaction scenarios during pregnancy (eg, local, long distance, one-way, two-way, and many-many), and choice of sharing media (eg, text, voice, and video). Additionally, the study revealed exclusions to social sharing capabilities in health technologies for these women. PMID:29653919

Social Interaction Needs and Entertainment Approaches to Pregnancy Well-Being in mHealth Technology Design for Low-Income Transmigrant Women: Qualitative Codesign Study.

PubMed

AlJaberi, Hana

2018-04-13

Low-income Caribbean transmigrant women face unique health challenges during pregnancy that set forth multidimensional implications for the design of mobile health (mHealth). Acknowledgment of the unique health needs of low-income Caribbean immigrant women in the United States and what that entails regarding technology design remains rarely examined in the literature of mHealth technologies. The goal of this study was to reveal the needs and gaps in mHealth interventions for pregnant immigrant women not yet realized in this field. These understandings reveal design opportunities for mHealth. The use of the qualitative participatory action research approach of codesign workshops in this study resulted in design solutions by the participants after reflecting on their earlier focus group discussions. The highlights are not the resulting designs per se but rather the inferences derived from the researcher reflecting on these designs. The designs exposed two themes relevant to this paper. First, the participants desired the inclusion and rebuilding of social and organizational relationships in mHealth. The resulting designs formulate an understanding of the women's health-related social support needs and how technology can facilitate them. Second, the participants wanted entertainment with an element of social participation incorporated in mHealth pregnancy management interventions. This brings attention to the role entertainment can add to the impact mHealth can deliver for pregnancy well-being. The study concluded with an examination of social and entertainment design implications that reveal pregnant immigrant women's virtual health-related sharing habits, choice of sharing interaction scenarios during pregnancy (eg, local, long distance, one-way, two-way, and many-many), and choice of sharing media (eg, text, voice, and video). Additionally, the study revealed exclusions to social sharing capabilities in health technologies for these women. ©Hana AlJaberi. Originally published in JMIR Mhealth and Uhealth (http://mhealth.jmir.org), 13.04.2018.

Cultural and Family Challenges to Managing Type 2 Diabetes in Immigrant Chinese Americans

PubMed Central

Chesla, Catherine A.; Chun, Kevin M.; Kwan, Christine M.L.

2009-01-01

OBJECTIVE Although Asians demonstrate elevated levels of type 2 diabetes, little attention has been directed to their unique cultural beliefs and practices regarding diabetes. We describe cultural and family challenges to illness management in foreign-born Chinese American patients with type 2 diabetes and their spouses. RESEARCH DESIGN AND METHODS This was an interpretive comparative interview study with 20 foreign-born Chinese American couples (n = 40) living with type 2 diabetes. Multiple (six to seven) semistructured interviews with each couple in individual, group, and couple settings elicited beliefs about diabetes and narratives of care within the family and community. Interpretive narrative and thematic analysis were completed. A separate respondent group of 19 patients and spouses who met the inclusion criteria reviewed and confirmed the themes developed from the initial couples. RESULTS Cultural and family challenges to diabetes management within foreign-born Chinese American families included how 1) diabetes symptoms challenged family harmony, 2) dietary prescriptions challenged food beliefs and practices, and 3) disease management requirements challenged established family role responsibilities. CONCLUSIONS Culturally nuanced care with immigrant Chinese Americans requires attentiveness to the social context of disease management. Patients' and families' disease management decisions are seldom made independent of their concerns for family well-being, family face, and the reciprocal responsibilities required by varied family roles. Framing disease recommendations to include cultural concerns for balance and significant food rituals are warranted. PMID:19628812

Pharmacokinetic studies in children: recommendations for practice and research.

PubMed

Barker, Charlotte I S; Standing, Joseph F; Kelly, Lauren E; Hanly Faught, Lauren; Needham, Allison C; Rieder, Michael J; de Wildt, Saskia N; Offringa, Martin

2018-04-19

Optimising the dosing of medicines for neonates and children remains a challenge. The importance of pharmacokinetic (PK) and pharmacodynamic (PD) research is recognised both in medicines regulation and paediatric clinical pharmacology, yet there remain barriers to undertaking high-quality PK and PD studies. While these studies are essential in understanding the dose-concentration-effect relationship and should underpin dosing recommendations, this review examines how challenges affecting the design and conduct of paediatric pharmacological studies can be overcome using targeted pharmacometric strategies. Model-based approaches confer benefits at all stages of the drug life-cycle, from identifying the first dose to be used in children, to clinical trial design, and optimising the dosing regimens of older, off-patent medications. To benefit patients, strategies to ensure that new PK, PD and trial data are incorporated into evidence-based dosing recommendations are needed. This review summarises practical strategies to address current challenges, particularly the use of model-based (pharmacometric) approaches in study design and analysis. Recommendations for practice and directions for future paediatric pharmacological research are given, based on current literature and our joint international experience. Success of PK research in children requires a robust infrastructure, with sustainable funding mechanisms at its core, supported by political and regulatory initiatives, and international collaborations. There is a unique opportunity to advance paediatric medicines research at an unprecedented pace, bringing the age of evidence-based paediatric pharmacotherapy into sight. © Article author(s) (or their employer(s) unless otherwise stated in the text of the article) 2018. All rights reserved. No commercial use is permitted unless otherwise expressly granted.

DOE Office of Scientific and Technical Information (OSTI.GOV)

Sanz Rodrigo, Javier; Chávez Arroyo, Roberto Aurelio; Moriarty, Patrick

The increasing size of wind turbines, with rotors already spanning more than 150 m diameter and hub heights above 100 m, requires proper modeling of the atmospheric boundary layer (ABL) from the surface to the free atmosphere. Furthermore, large wind farm arrays create their own boundary layer structure with unique physics. This poses significant challenges to traditional wind engineering models that rely on surface-layer theories and engineering wind farm models to simulate the flow in and around wind farms. However, adopting an ABL approach offers the opportunity to better integrate wind farm design tools and meteorological models. The challenge ismore » how to build the bridge between atmospheric and wind engineering model communities and how to establish a comprehensive evaluation process that identifies relevant physical phenomena for wind energy applications with modeling and experimental requirements. A framework for model verification, validation, and uncertainty quantification is established to guide this process by a systematic evaluation of the modeling system at increasing levels of complexity. In terms of atmospheric physics, 'building the bridge' means developing models for the so-called 'terra incognita,' a term used to designate the turbulent scales that transition from mesoscale to microscale. This range of scales within atmospheric research deals with the transition from parameterized to resolved turbulence and the improvement of surface boundary-layer parameterizations. The coupling of meteorological and wind engineering flow models and the definition of a formal model evaluation methodology, is a strong area of research for the next generation of wind conditions assessment and wind farm and wind turbine design tools. Some fundamental challenges are identified in order to guide future research in this area.« less

International Student Mental Health

ERIC Educational Resources Information Center

Prieto-Welch, Susan L.

2016-01-01

This chapter describes the mental health status of international students in institutions of higher education, unique challenges these students face and their impact on mental health, and suggestions for ways to address these challenges.

Sustainable Approaches for Materials Management in Remote, Economically Challenged Areas of the Pacific

EPA Science Inventory

Remote, economically challenged areas in the Commonwealth of the Northern Marianas Islands (CNMI) and American Samoa in the US Pacific island territories face unique challenges with respect to solid waste management. These islands are remote and isolated, with some islands suppo...

Solar Probe Plus: Mission design challenges and trades

NASA Astrophysics Data System (ADS)

Guo, Yanping

2010-11-01

NASA plans to launch the first mission to the Sun, named Solar Probe Plus, as early as 2015, after a comprehensive feasibility study that significantly changed the original Solar Probe mission concept. The original Solar Probe mission concept, based on a Jupiter gravity assist trajectory, was no longer feasible under the new guidelines given to the mission. A complete redesign of the mission was required, which called for developing alternative trajectories that excluded a flyby of Jupiter. Without the very powerful gravity assist from Jupiter it was extremely difficult to get to the Sun, so designing a trajectory to reach the Sun that is technically feasible under the new mission guidelines became a key enabler to this highly challenging mission. Mission design requirements and challenges unique to this mission are reviewed and discussed, including various mission scenarios and six different trajectory designs utilizing various planetary gravity assists that were considered. The V 5GA trajectory design using five Venus gravity assists achieves a perihelion of 11.8 solar radii ( RS) in 3.3 years without any deep space maneuver (DSM). The V 7GA trajectory design reaches a perihelion of 9.5 RS using seven Venus gravity assists in 6.39 years without any DSM. With nine Venus gravity assists, the V 9GA trajectory design shows a solar orbit at inclination as high as 37.9° from the ecliptic plane can be achieved with the time of flight of 5.8 years. Using combined Earth and Venus gravity assists, as close as 9 RS from the Sun can be achieved in less than 10 years of flight time at moderate launch C3. Ultimately the V 7GA trajectory was chosen as the new baseline mission trajectory. Its design allowing for science investigation right after launch and continuing for nearly 7 years is unprecedented for interplanetary missions. The redesigned Solar Probe Plus mission is not only feasible under the new guidelines but also significantly outperforms the original mission concept in both technical implementation and scientific returns.

The ability of environmental healthcare design strategies To impact event related anxiety in paediatric patients: A comprehensive systematic review.

PubMed

Norton-Westwood, Deborah; Pearson, Alan; Robertson-Malt, Suzanne

Background Children's' hospitals are by definition hospitals specialized in all aspects of children's care, but are they and if so, how is that achieved? Are healthcare facilities more than a 'space' in which to ask medical questions, seek answers and obtain treatment? Some suggest that the very design of a space can positively or negatively impact healing, hence the term referred to by those in the architectural community as 'healing spaces'. To date empirical studies to provide evidence to this effect, although growing in number, are still few. What is known is that hospitals, doctor's offices and dental offices alike unintentionally create an atmosphere, particularly for children, that add to an already heightened level of anxiety and fear. Designing a children's hospital, unlike a generalist facility, presents a unique and significant challenge. Those involved in designing such hospitals are faced with the opportunity and responsibility to care for and respond to the needs of children across the age spectrum; infants to toddlers, school aged children to adolescents. As healthcare professionals and architects, it is our responsibility to create healthcare facilities that are of purposeful design; anticipating and alleviating children's anxiety and fear wherever possible.Objectives The objective of this systematic review is to evaluate the effects of environmental design strategies in healthcare institutions such as hospitals and dental offices on event-related anxiety in the paediatric population.Inclusion Criteria This comprehensive systematic review involved children from the age of 1 to 18 years of age admitted to a healthcare facility with the primary outcomes of interest being four key design strategies: positive distraction; elimination of environmental stressors; access to social support and choice (control); and connection to nature.Search Strategy Using the Joanna Briggs defined three step search strategy, both published and unpublished studies were sought from the period of 1980 to 2010.Methods of the Review Data for each study was extracted and assessed by two independent reviewers for methodological validity prior to inclusion in the review using the Joanna Briggs Institute standardised critical appraisal instruments for Qualitative data (JBI-QARI) and for the Meta Analysis of Statistics Assessment (JBI-MAStARI).Results Twenty studies were reviewed, seven of a descriptive experimental design, three of mixed methodologies and thirteen of various qualitative research design methodologies inclusive of Observational, Grounded Theory, Ethnography and Phenomenology.Conclusions The design of the built environment does have the ability to impact either positively or negatively the level of anxiety and fear that children experience when exposed to a healthcare setting. The coping strategies engaged by and unique to each paediatric age group need to not only be understood but supported and reflected in the built environment.Implications for research Architects and healthcare researchers need to collaborate to establish a solid base of evidence related to this important area of interest. Irrespective of the challenges that researchers face in attempting to randomise, manipulate and control the numerous environmental variables that impact a question such as this, such challenges need not, nor should not, prevent or discourage future research. An innovative solution to the challenges faced by researchers in this field is the use of computer modelling and/ or simulation of the hospital environment. Through the use of simulated environments researchers can directly observe user preferences and/ physiological responses.Implication for practice This review highlights an insightful look into the preferences of children as consumers. Although sample sizes were small and results were not quantified in measurable outcomes, the ability for such studies to inform design should not be underestimated. Design strategies both from a practical perspective of minimal cost to construction projects warranting extensive resources are discussed.

Coupling of Large Amplitude Inversion with Other States

NASA Astrophysics Data System (ADS)

Pearson, John; Yu, Shanshan

2016-06-01

The coupling of a large amplitude motion with a small amplitude vibration remains one of the least well characterized problems in molecular physics. Molecular inversion poses a few unique and not intuitively obvious challenges to the large amplitude motion problem. In spite of several decades of theoretical work numerous challenges in calculation of transition frequencies and more importantly intensities persist. The most challenging aspect of this problem is that the inversion coordinate is a unique function of the overall vibrational state including both the large and small amplitude modes. As a result, the r-axis system and the meaning of the K-quantum number in the rotational basis set are unique to each vibrational state of large or small amplitude motion. This unfortunate reality has profound consequences to calculation of intensities and the coupling of nearly degenerate vibrational states. The case of NH3 inversion and inversion through a plane of symmetry in alcohols will be examined to find a general path forward.

The 1991-1992 walking robot design

NASA Technical Reports Server (NTRS)

Azarm, Shapour; Dayawansa, Wijesurija; Tsai, Lung-Wen; Peritt, Jon

1992-01-01

The University of Maryland Walking Machine team designed and constructed a robot. This robot was completed in two phases with supervision and suggestions from three professors and one graduate teaching assistant. Bob was designed during the Fall Semester 1991, then machined, assembled, and debugged in the Spring Semester 1992. The project required a total of 4,300 student hours and cost under $8,000. Mechanically, Bob was an exercise in optimization. The robot was designed to test several diverse aspects of robotic potential, including speed, agility, and stability, with simplicity and reliability holding equal importance. For speed and smooth walking motion, the footpath contained a long horizontal component; a vertical aspect was included to allow clearance of obstacles. These challenges were met with a leg design that utilized a unique multi-link mechanism which traveled a modified tear-drop footpath. The electrical requirements included motor, encoder, and voice control circuitry selection, manual controller manufacture, and creation of sensors for guidance. Further, there was also a need for selection of the computer, completion of a preliminary program, and testing of the robot.

Unique Approach to Dental Management of Children with Hearing Impairment.

PubMed

Renahan, Navanith; Varma, R Balagopal; Kumaran, Parvathy; Xavier, Arun M

2017-01-01

The number of deaf children has dramatically increased in the past few decades. These children present to the pediatric dentist a unique set of challenges mostly pertaining to the establishment of communication with them. There have been very few attempts in the past to break down these challenges and formulate a strategy on how to manage them effectively. This is a case report of a child who was successfully managed using two different modes of communication. Finally, the advantages and disadvantages are mentioned, and a common strategy incorporating the positives of both the methods has been devised. Renahan N, Varma RB, Kumaran P, Xavier AM. Unique Approach to Dental Management of Children with Hearing Impairment. Int J Clin Pediatr Dent 2017;10(1):107-110.

Rotorcraft Health Management Issues and Challenges

NASA Technical Reports Server (NTRS)

Zakrajsek, James J.; Dempsey, Paula J.; Huff, Edward M.; Augustin, Michael; Safa-Bakhsh, Robab; Ephraim, Piet; Grabil, Paul; Decker, Harry J.

2006-01-01

This paper presents an overview of health management issues and challenges that are specific to rotorcraft. Rotorcraft form a unique subset of air vehicles in that their propulsion system is used not only for propulsion, but also serves as the primary source of lift and maneuvering of the vehicle. No other air vehicle relies on the propulsion system to provide these functions through a transmission system with single critical load paths without duplication or redundancy. As such, health management of the power train is a critical and unique part of any rotorcraft health management system. This paper focuses specifically on the issues and challenges related to the dynamic mechanical components in the main power train. This includes the transmission and main rotor mechanisms. This paper will review standard practices used for rotorcraft health management, lessons learned from fielded trials, and future challenges.

Medical Operational Challenges in the Expedition 16 Landing and Recovery

NASA Technical Reports Server (NTRS)

Moynihan, S.; Johnston, S. L.; Ilcus, L. S.; Shevchenko, V.

2009-01-01

On April 19, 2008 the crew of Expedition 16 left the International Space Station and returned to earth via their Soyuz TMA-11 capsule after 192 days on orbit. Their capsule experienced the second consecutive and third ballistic reentry in the last 10 TMA recoveries and landed approximately 260 miles (420 km) from the prime landing site. Issues: The purpose of this presentation will be to describe, not only the typical medical operational challenges faced by Flight Surgeons recovering a long duration crew from space, but also address the unique challenges that existed with the Expedition 16 landing and crew recovery. Nominal Soyuz recovery challenges include remote recovery sites with crew exposures to sleep shifting and fatigue, dehydration, hypothermia and hyperthermia, and rotational, sustained, and impact g-forces. These environmental factors coupled with the patho-physiologic neuro-vestibular and orthostatic intolerance changes that occur secondary to the crews reintroduction into the earth s gravity field will be detailed. Additional challenges that were unique to this expedition included a ballistic reentry with higher g-loads, the presence of fire outside of the capsule on landing, a contingency medical event of a ground support personnel, and loss of communications with the crew just prior to landing and during recovery operations. Conclusions: In spite of these unique challenges the Russian Search and Rescue Forces and Medical Support personnel along with U.S. Medical Support performed well together. Possible improvements in training and coordination will be discussed.

Supporting Middle School Students Whose Parents Are Deployed: Challenges and Strategies for Schools

ERIC Educational Resources Information Center

Williams, Brenda

2013-01-01

Middle school students from military families face unique challenges, especially when their parents are deployed. Among the challenges they experience are frequent relocations; issues that affect academic achievement; uncertainty; and changes in roles, responsibilities, and relationships at home. Reunification involves issues of the returning…

Essential Tensions in Interdisciplinary Scholarship: Navigating Challenges in Affect, Epistemologies, and Structure in Environment-Society Research Centers

ERIC Educational Resources Information Center

Turner, V. Kelly; Benessaiah, Karina; Warren, Scott; Iwaniec, David

2015-01-01

Scholars have enumerated unique challenges to collaborative interdisciplinary research, many of which evade prescriptive solutions. Some of these challenges can be understood as "essential tensions," necessary and persistent contradictory imperatives in the scientific process. Drawing from interviews with internationally renowned…

Student Media Production to Meet Challenges in Climate Change Science Education

ERIC Educational Resources Information Center

Rooney-Varga, Juliette N.; Brisk, Angelica Allende; Adams, Elizabeth; Shuldman, Elizabeth; Rath, Kenneth

2014-01-01

While the need for effective climate change education is growing, this area of geoscience also poses unique educational challenges. These challenges include the politicization of climate change, the psychological and affective responses it elicits, and common misconceptions, which can all create barriers to learning. Here, we present an…

The art and science of integrating Undoing Racism with CBPR: challenges of pursuing NIH funding to investigate cancer care and racial equity.

PubMed

Yonas, Michael A; Jones, Nora; Eng, Eugenia; Vines, Anissa I; Aronson, Robert; Griffith, Derek M; White, Brandolyn; DuBose, Melvin

2006-11-01

In this nation, the unequal burden of disease among People of Color has been well documented. One starting point to eliminating health disparities is recognizing the existence of inequities in health care delivery and identifying the complexities of how institutional racism may operate within the health care system. In this paper, we explore the integration of community-based participatory research (CBPR) principles with an Undoing Racism process to conceptualize, design, apply for, and secure National Institutes of Health (NIH) funding to investigate the complexities of racial equity in the system of breast cancer care. Additionally, we describe the sequence of activities and "necessary conflicts" managed by our Health Disparities Collaborative to design and submit an application for NIH funding. This process of integrating CBPR principles with anti-racist community organizing presented unique challenges that were negotiated only by creating a strong foundation of trusting relationships that viewed conflict as being necessary. The process of developing a successful NIH grant proposal illustrated a variety of important lessons associated with the concepts of cultural humility and cultural safety. For successfully conducting CBPR, major challenges have included: assembling and mobilizing a partnership; the difficulty of establishing a shared vision and purpose for the group; the problem of maintaining trust; and the willingness to address differences in institutional cultures. Expectation, acceptance and negotiation of conflict were essential in the process of developing, preparing and submitting our NIH application. Central to negotiating these and other challenges has been the utilization of a CBPR approach.

Surrogate assisted multidisciplinary design optimization for an all-electric GEO satellite

NASA Astrophysics Data System (ADS)

Shi, Renhe; Liu, Li; Long, Teng; Liu, Jian; Yuan, Bin

2017-09-01

State-of-the-art all-electric geostationary earth orbit (GEO) satellites use electric thrusters to execute all propulsive duties, which significantly differ from the traditional all-chemical ones in orbit-raising, station-keeping, radiation damage protection, and power budget, etc. Design optimization task of an all-electric GEO satellite is therefore a complex multidisciplinary design optimization (MDO) problem involving unique design considerations. However, solving the all-electric GEO satellite MDO problem faces big challenges in disciplinary modeling techniques and efficient optimization strategy. To address these challenges, we presents a surrogate assisted MDO framework consisting of several modules, i.e., MDO problem definition, multidisciplinary modeling, multidisciplinary analysis (MDA), and surrogate assisted optimizer. Based on the proposed framework, the all-electric GEO satellite MDO problem is formulated to minimize the total mass of the satellite system under a number of practical constraints. Then considerable efforts are spent on multidisciplinary modeling involving geosynchronous transfer, GEO station-keeping, power, thermal control, attitude control, and structure disciplines. Since orbit dynamics models and finite element structural model are computationally expensive, an adaptive response surface surrogate based optimizer is incorporated in the proposed framework to solve the satellite MDO problem with moderate computational cost, where a response surface surrogate is gradually refined to represent the computationally expensive MDA process. After optimization, the total mass of the studied GEO satellite is decreased by 185.3 kg (i.e., 7.3% of the total mass). Finally, the optimal design is further discussed to demonstrate the effectiveness of our proposed framework to cope with the all-electric GEO satellite system design optimization problems. This proposed surrogate assisted MDO framework can also provide valuable references for other all-electric spacecraft system design.

NASA Space Rocket Logistics Challenges

NASA Technical Reports Server (NTRS)

Bramon, Chris; Neeley, James R.; Jones, James V.; Watson, Michael D.; Inman, Sharon K.; Tuttle, Loraine

2014-01-01

The Space Launch System (SLS) is the new NASA heavy lift launch vehicle in development and is scheduled for its first mission in 2017. SLS has many of the same logistics challenges as any other large scale program. However, SLS also faces unique challenges. This presentation will address the SLS challenges, along with the analysis and decisions to mitigate the threats posed by each.

Catalytic asymmetric trifluoromethylthiolation via enantioselective [2,3]-sigmatropic rearrangement of sulfonium ylides

NASA Astrophysics Data System (ADS)

Zhang, Zhikun; Sheng, Zhe; Yu, Weizhi; Wu, Guojiao; Zhang, Rui; Chu, Wen-Dao; Zhang, Yan; Wang, Jianbo

2017-10-01

The trifluoromethylthio (SCF3) functional group has been of increasing importance in drug design and development as a consequence of its unique electronic properties and high stability coupled with its high lipophilicity. As a result, methods to introduce this highly electronegative functional group have attracted considerable attention in recent years. Although significant progress has been made in the introduction of SCF3 functionality into a variety of molecules, there remain significant challenges regarding the enantioselective synthesis of SCF3-containing compounds. Here, an asymmetric trifluoromethylthiolation that proceeds through the enantioselective [2,3]-sigmatropic rearrangement of a sulfonium ylide generated from a metal carbene and sulfide (Doyle-Kirmse reaction) has been developed using chiral Rh(II) and Cu(I) catalysts. This transformation features mild reaction conditions and excellent enantioselectivities (up to 98% yield and 98% e.e.), thus providing a unique, highly efficient and enantioselective method for the construction of C(sp3)-SCF3 bonds bearing chiral centres.

Advanced nanocarriers based on heparin and its derivatives for cancer management.

PubMed

Yang, Xiaoye; Du, Hongliang; Liu, Jiyong; Zhai, Guangxi

2015-02-09

To obtain a satisfying anticancer effect, rationally designed nanocarriers are intensively studied. In this field, heparin and its derivatives have been widely attempted recently as potential component of nanocarriers due to their unique biological and physiochemical features, especially the anticancer activity. This review focuses on state-of-the-art nanocarriers with heparin/heparin derivatives as backbone or coating material. At the beginning, the unique advantages of heparin used in cancer nanotechnology are discussed. After that, different strategies of heparin chemical modification are reviewed, laying the foundation of developing various nanocarriers. Then a systematic summary of diverse nanoparticles with heparin as component is exhibited, involving heparin-drug conjugate, polymeric nanoparticles, nanogels, polyelectrolyte complex nanoparticles, and heparin-coated organic and inorganic nanoparticles. The application of these nanoparticles in various novel cancer therapy (containing targeted therapy, magnetic therapy, photodynamic therapy, and gene therapy) will be highlighted. Finally, future challenges and opportunities of heparin-based biomaterials in cancer nanotechnology are discussed.

Experimental Investigation and Fundamental Understanding of a Slowed UH-60A Rotor at High Advance Ratios

NASA Technical Reports Server (NTRS)

Datta, Anubhav; Yeo, Hyeonsoo; Norman, Thomas R.

2011-01-01

This paper describes and analyzes the measurements from a full-scale, slowed RPM, UH-60A rotor tested at the National Full-Scale Aerodynamics Complex 40- by 80- ft wind tunnel up to an advance ratio of 1.0. A comprehensive set of measurements, that includes performance, blade loads, hub loads and pressures/airloads makes this data set unique. The measurements reveal new and rich aeromechanical phenomena that are special to this exotic regime. These include reverse chord dynamic stall, retreating side impulse in pitch-link load, large inboard-outboard elastic twist differential, supersonic flow at low subsonic advancing tip Mach numbers, diminishing rotor forces yet dramatic build up of blade loads, and dramatic blade loads yet benign levels of vibratory hub loads. The objective of this research is the fundamental understanding of these unique aeromechanical phenomena. The intent is to provide useful knowledge for the design of high speed, high efficiency, slowed RPM rotors of the future and a challenging database for advanced analyses validation.

Sequence, Structural Analysis and Metrics to Define the Unique Dynamic Features of the Flap Regions Among Aspartic Proteases.

PubMed

McGillewie, Lara; Ramesh, Muthusamy; Soliman, Mahmoud E

2017-10-01

Aspartic proteases are a class of hydrolytic enzymes that have been implicated in a number of diseases such as HIV, malaria, cancer and Alzheimer's. The flap region of aspartic proteases is a characteristic unique structural feature of these enzymes; and found to have a profound impact on protein overall structure, function and dynamics. Flap dynamics also plays a crucial role in drug binding and drug resistance. Therefore, understanding the structure and dynamic behavior of this flap regions is crucial in the design of potent and selective inhibitors against aspartic proteases. Defining metrics that can describe the flap motion/dynamics has been a challenging topic in literature. This review is the first attempt to compile comprehensive information on sequence, structure, motion and metrics used to assess the dynamics of the flap region of different aspartic proteases in "one pot". We believe that this review would be of critical importance to the researchers from different scientific domains.

Characterization of an array of honeys of different types and botanical origins through fluorescence emission based on LEDs.

PubMed

Lastra-Mejías, Miguel; Torreblanca-Zanca, Albertina; Aroca-Santos, Regina; Cancilla, John C; Izquierdo, Jesús G; Torrecilla, José S

2018-08-01

A set of 10 honeys comprising a diverse range of botanical origins have been successfully characterized through fluorescence spectroscopy using inexpensive light-emitting diodes (LEDs) as light sources. It has been proven that each LED-honey combination tested originates a unique emission spectrum, which enables the authentication of every honey, being able to correctly label it with its botanical origin. Furthermore, the analysis was backed up by a mathematical analysis based on partial least square models which led to a correct classification rate of each type of honey of over 95%. Finally, the same approach was followed to analyze rice syrup, which is a common honey adulterant that is challenging to identify when mixed with honey. A LED-dependent and unique fluorescence spectrum was found for the syrup, which presumably qualifies this approach for the design of uncomplicated, fast, and cost-effective quality control and adulteration assessing tools for different types of honey. Copyright © 2018 Elsevier B.V. All rights reserved.

The space shuttle program from challenge to achievement: Space exploration rolling on tires

NASA Technical Reports Server (NTRS)

Felder, G. L.

1985-01-01

The Space Shuttle Transportation System is the first space program to employ the pneumatic tire as a part of space exploration. For aircraft tires, this program establishes new expectations as to what constitutes acceptable performance within a set of tough environmental and operational conditions. Tire design, stresses the usual low weight, high load, high speed, and excellent air retention features but at extremes well outside industry standards. Tires will continue to be an integral part of the Shuttle's landing phase in the immediate future since they afford a unique combination of directional control, braking traction, flotation and shock absorption not available by other systems.

Rapid Construction of a Benzo-Fused Indoxamycin Core Enabled by Site-Selective C-H Functionalizations.

PubMed

Bedell, T Aaron; Hone, Graham A B; Valette, Damien; Yu, Jin-Quan; Davies, Huw M L; Sorensen, Erik J

2016-07-11

Methods for functionalizing carbon-hydrogen bonds are featured in a new synthesis of the tricyclic core architecture that characterizes the indoxamycin family of secondary metabolites. A unique collaboration between three laboratories has engendered a design for synthesis featuring two sequential C-H functionalization reactions, namely a diastereoselective dirhodium carbene insertion followed by an ester-directed oxidative Heck cyclization, to rapidly assemble the congested tricyclic core of the indoxamycins. This project exemplifies how multi-laboratory collaborations can foster conceptually novel approaches to challenging problems in chemical synthesis. © 2016 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

A Multidisciplinary Investigation of a Polycythemia Vera Cancer Cluster of Unknown Origin

PubMed Central

Seaman, Vincent; Dearwent, Steve M; Gable, Debra; Lewis, Brian; Metcalf, Susan; Orloff, Ken; Tierney, Bruce; Zhu, Jane; Logue, James; Marchetto, David; Ostroff, Stephen; Hoffman, Ronald; Xu, Mingjiang; Carey, David; Erlich, Porat; Gerhard, Glenn; Roda, Paul; Iannuzzo, Joseph; Lewis, Robert; Mellow, John; Mulvihill, Linda; Myles, Zachary; Wu, Manxia; Frank, Arthur; Gross-Davis, Carol Ann; Klotz, Judith; Lynch, Adam; Weissfeld, Joel; Weinberg, Rona; Cole, Henry

2010-01-01

Cancer cluster investigations rarely receive significant public health resource allocations due to numerous inherent challenges and the limited success of past efforts. In 2008, a cluster of polycythemia vera, a rare blood cancer with unknown etiology, was identified in northeast Pennsylvania. A multidisciplinary group of federal and state agencies, academic institutions, and local healthcare providers subsequently developed a multifaceted research portfolio designed to better understand the cause of the cluster. This research agenda represents a unique and important opportunity to demonstrate that cancer cluster investigations can produce desirable public health and scientific outcomes when necessary resources are available. PMID:20617023

Landing Site and Traverse Plan Development for Resource Prospector

NASA Technical Reports Server (NTRS)

Elphic, R. C.; Colaprete, A.; Shirley, M.; McGovern, A.; Beyer, R.; Siegler, M. A.

2017-01-01

Resource Prospector (RP) will be the first lunar surface robotic expedition to explore the character and feasibility of in situ resource utilization at the lunar poles. It is aimed at determining where, and how much, hydrogen-bearing and other volatiles are sequestered in polar cold traps. To meet its goals, the mission should land where the likelihood of finding polar volatiles is high [1,2,3]. The operational environment is challenging: very low sun elevations, long shadows cast by even moderate relief, cryogenic subsurface temperatures, unknown regolith properties, and very dynamic sun and Earth communications geometries force a unique approach to landing, traverse design and mission operations.

Resource Prospector Landing Site and Traverse Plan Development

NASA Technical Reports Server (NTRS)

Elphic, R. C.; Colaprete, A.; Shirley, M.; McGovern, A.; Beyer, R.

2016-01-01

Resource Prospector (RP) will be the first lunar surface robotic expedition to explore the character and feasibility of in situ resource utilization at the lunar poles. It is aimed at determining where, and how much, hydrogen-bearing and other volatiles are sequestered in polar cold traps. To meet its goals, the mission should land where the likelihood of finding polar volatiles is high. The operational environment is challenging: very low sun elevations, long shadows cast by even moderate relief, cryogenic subsurface temperatures, unknown regolith properties, and very dynamic sun and Earth communications geometries force a unique approach to landing, traverse design and mission operations.

Landing Site and Traverse Plan Development for Resource Prospector

NASA Technical Reports Server (NTRS)

Elphic, R. C.; Colaprete, A.; Shirley, M.; A.McGovern; Beyer, R.; Siegler, M. A.

2017-01-01

Resource Prospector (RP) will be the first lunar surface robotic expedition to explore the character and feasibility of in situ resource utilization at the lunar poles. It is aimed at determining where, and how much, hydrogen-bearing and other volatiles are sequestered in polar cold traps. To meet its goals, the mission should land where the likelihood of finding polar volatiles is high. The operational environment is challenging: very low sun elevations, long shadows cast by even moderate relief, cryogenic subsurface temperatures, unknown regolith properties, and very dynamic sun and Earth communications geometries force a unique approach to landing, traverse design and mission operations.

Eclipse of the Floating Orbs: Controlling Robots on the International Space Station

NASA Technical Reports Server (NTRS)

Wheeler, D. W.

2017-01-01

I will describe the Control Station for a free-flying robot called Astrobee. Astrobee will serve as a mobile camera, sensor platform, and research testbed when it is launched to the International Space Station (ISS)in 2017. Astronauts on the ISS as well as ground-based users will control Astrobee using the Eclipse-based Astrobee Control Station. Designing theControl Station for use in space presented unique challenges, such as allowing the intuitive input of 3D information without a mouse or trackpad. Come to this talk to learn how Eclipse is used in an environment few humans have the chance to visit.

Oncology disease management.

PubMed

Fetterolf, Donald E; Terry, Rachel

2007-02-01

Oncologic conditions are ubiquitous medical illnesses that present a particular challenge for medical management programs designed to address quality and cost issues in patient populations. Disease management strategies represent a reasonable and effective approach for employers and health plans in their arsenal of health management strategies. Multiple reasons exist for the development of specialized disease management programs that deal with cancer patients, some unique to this group of individuals. Health plans and/or employers have solid justification for addressing these issues directly through programs developed specifically to work with cancer patients. Whether developed within a health plan, or "carved out" to an external vendor, proper evaluation of outcomes is essential.

Accelerating Pediatric Cancer Drug Development: Challenges and Opportunities for Pediatric Master Protocols.

PubMed

Khan, Tahira; Stewart, Mark; Blackman, Samuel; Rousseau, Raphaël; Donoghue, Martha; Cohen, Kenneth; Seibel, Nita; Fleury, Mark; Benettaib, Bouchra; Malik, Raleigh; Vassal, Gilles; Reaman, Gregory

2018-01-01

Although outcomes for children with cancer have significantly improved over the past 40 years, there has been little progress in the treatment of some pediatric cancers, particularly when advanced. Additionally, clinical trial options and availability are often insufficient. Improved genomic and immunologic understanding of pediatric cancers, combined with innovative clinical trial designs, may provide an enhanced opportunity to study childhood cancers. Master protocols, which incorporate the use of precision medicine approaches, coupled with the ability to quickly assess the safety and effectiveness of new therapies, have the potential to accelerate early-phase clinical testing of novel therapeutics and which may result in more rapid approval of new drugs for children with cancer. Designing and conducting master protocols for children requires addressing similar principles and requirements as traditional adult oncology trials, but there are also unique considerations for master protocols conducted in children with cancer. The purpose of this paper is to define the key challenges and opportunities associated with this approach in order to ensure that master protocols can be adapted to benefit children and adolescents and ensure that adequate data are captured to advance, in parallel, the clinical development of investigational agents for children with cancer.

Advances in Orion's On-Orbit Guidance and Targeting System Architecture

NASA Technical Reports Server (NTRS)

Scarritt, Sara K.; Fill, Thomas; Robinson, Shane

2015-01-01

NASA's manned spaceflight programs have a rich history of advancing onboard guidance and targeting technology. In order to support future missions, the guidance and targeting architecture for the Orion Multi-Purpose Crew Vehicle must be able to operate in complete autonomy, without any support from the ground. Orion's guidance and targeting system must be sufficiently flexible to easily adapt to a wide array of undecided future missions, yet also not cause an undue computational burden on the flight computer. This presents a unique design challenge from the perspective of both algorithm development and system architecture construction. The present work shows how Orion's guidance and targeting system addresses these challenges. On the algorithm side, the system advances the state-of-the-art by: (1) steering burns with a simple closed-loop guidance strategy based on Shuttle heritage, and (2) planning maneuvers with a cutting-edge two-level targeting routine. These algorithms are then placed into an architecture designed to leverage the advantages of each and ensure that they function in concert with one another. The resulting system is characterized by modularity and simplicity. As such, it is adaptable to the on-orbit phases of any future mission that Orion may attempt.

How Do Lessons Learned on the International Space Station (ISS) Help Plan Life Support for Mars?

NASA Technical Reports Server (NTRS)

Jones, Harry W.; Hodgson, Edward W.; Gentry, Gregory J.; Kliss, Mark H.

2016-01-01

How can our experience in developing and operating the International Space Station (ISS) guide the design, development, and operation of life support for the journey to Mars? The Mars deep space Environmental Control and Life Support System (ECLSS) must incorporate the knowledge and experience gained in developing ECLSS for low Earth orbit, but it must also meet the challenging new requirements of operation in deep space where there is no possibility of emergency resupply or quick crew return. The understanding gained by developing ISS flight hardware and successfully supporting a crew in orbit for many years is uniquely instructive. Different requirements for Mars life support suggest that different decisions may be made in design, testing, and operations planning, but the lessons learned developing the ECLSS for ISS provide valuable guidance.

Millimeter-scale MEMS enabled autonomous systems: system feasibility and mobility

NASA Astrophysics Data System (ADS)

Pulskamp, Jeffrey S.

2012-06-01

Millimeter-scale robotic systems based on highly integrated microelectronics and micro-electromechanical systems (MEMS) could offer unique benefits and attributes for small-scale autonomous systems. This extreme scale for robotics will naturally constrain the realizable system capabilities significantly. This paper assesses the feasibility of developing such systems by defining the fundamental design trade spaces between component design variables and system level performance parameters. This permits the development of mobility enabling component technologies within a system relevant context. Feasible ranges of system mass, required aerodynamic power, available battery power, load supported power, flight endurance, and required leg load bearing capability are presented for millimeter-scale platforms. The analysis illustrates the feasibility of developing both flight capable and ground mobile millimeter-scale autonomous systems while highlighting the significant challenges that must be overcome to realize their potential.

Facility design consideration for continuous mix production of class 1.3 propellant

NASA Technical Reports Server (NTRS)

Williamson, K. L.; Schirk, P. G.

1994-01-01

In November of 1989, NASA awarded the Advanced Solid Rocket Motor (ASRM) contract to Lockheed Missiles and Space Company (LMSC) for production of advanced solid rocket motors using the continuous mix process. Aerojet ASRM division (AAD) was selected as the facility operator and RUST International Corporation provided the engineering, procurement, and construction management services. The continuous mix process mandates that the mix and cast facilities be 'close-coupled' along with the premix facilities, creating unique and challenging requirements for the facility designer. The classical approach to handling energetic materials-division into manageable quantities, segregation, and isolation-was not available due to these process requirements and quantities involved. This paper provides a description of the physical facilities, the continuous mix process, and discusses the monitoring and detection techniques used to mitigate hazards and prevent an incident.

Capsule physics comparison of National Ignition Facility implosion designs using plastic, high density carbon, and beryllium ablators

NASA Astrophysics Data System (ADS)

Clark, D. S.; Kritcher, A. L.; Yi, S. A.; Zylstra, A. B.; Haan, S. W.; Weber, C. R.

2018-03-01

Indirect drive implosion experiments on the National Ignition Facility (NIF) [E. I. Moses et al., Phys. Plasmas 16, 041006 (2009)] have now tested three different ablator materials: glow discharge polymer plastic, high density carbon, and beryllium. How do these different ablators compare in current and proposed implosion experiments on NIF? What are the relative advantages and disadvantages of each? This paper compares these different ablator options in capsule-only simulations of current NIF experiments and potential future designs. The simulations compare the impact of the capsule fill tube, support tent, and interface surface roughness for each case, as well as all perturbations in combination. According to the simulations, each ablator is impacted by the various perturbation sources differently, and each material poses unique challenges in the pursuit of ignition on NIF.

Using Petri nets for experimental design in a multi-organ elimination pathway.

PubMed

Reshetova, Polina; Smilde, Age K; Westerhuis, Johan A; van Kampen, Antoine H C

2015-08-01

Genistein is a soy metabolite with estrogenic activity that may result in (un)favorable effects on human health. Elucidation of the mechanisms through which food additives such as genistein exert their beneficiary effects is a major challenge for the food industry. A better understanding of the genistein elimination pathway could shed light on such mechanisms. We developed a Petri net model that represents this multi-organ elimination pathway and which assists in the design of future experiments. Using this model we show that metabolic profiles solely measured in venous blood are not sufficient to uniquely parameterize the model. Based on simulations we suggest two solutions that provide better results: parameterize the model using gut epithelium profiles or add additional biological constrains in the model. Copyright © 2015 Elsevier Ltd. All rights reserved.

Low-Cost Approach to the Design and Fabrication of a LOX/RP-1 Injector

NASA Technical Reports Server (NTRS)

Shadoan, Michael D.; Sparks, Dave L.; Turner, James E. (Technical Monitor)

2000-01-01

NASA Marshall Space Flight Center (MSFC) has designed, built, and is currently testing Fastrac, a liquid oxygen (LOX)/RP-1 fueled 60K-lb thrust class rocket engine. One facet of Fastrac, which makes it unique is that it is the first large-scale engine designed and developed in accordance with the Agency's mandated "faster, better, cheaper" (FBC) program policy. The engine was developed under the auspices of MSFC's Low Cost Boost Technology office. Development work for the main injector actually began in 1993 in subscale form. In 1996, work began on the full-scale unit approximately 1 year prior to initiation of the engine development program. In order to achieve the value goals established by the FBC policy, a review of traditional design practices was necessary. This internal reevaluation would ultimately challenge more conventional methods of material selection. design process, and fabrication techniques. The effort was highly successful. This "new way" of thinking has resulted in an innovative injector design, one with reduced complexity and significantly lower cost. Application of lessons learned during this effort to new or existing designs can have a similar effect on costs and future program successes.

Towards Requirements in Systems Engineering for Aerospace IVHM Design

NASA Technical Reports Server (NTRS)

Saxena, Abhinav; Roychoudhury, Indranil; Lin, Wei; Goebel, Kai

2013-01-01

Health management (HM) technologies have been employed for safety critical system for decades, but a coherent systematic process to integrate HM into the system design is not yet clear. Consequently, in most cases, health management resorts to be an after-thought or 'band-aid' solution. Moreover, limited guidance exists for carrying out systems engineering (SE) on the subject of writing requirements for designs with integrated vehicle health management (IVHM). It is well accepted that requirements are key to developing a successful IVHM system right from the concept stage to development, verification, utilization, and support. However, writing requirements for systems with IVHM capability have unique challenges that require the designers to look beyond their own domains and consider the constraints and specifications of other interlinked systems. In this paper we look at various stages in the SE process and identify activities specific to IVHM design and development. More importantly, several relevant questions are posed that system engineers must address at various design and development stages. Addressing these questions should provide some guidance to systems engineers towards writing IVHM related requirements to ensure that appropriate IVHM functions are built into the system design.

Immuno-oncology Clinical Trial Design: Limitations, Challenges, and Opportunities

PubMed Central

Baik, Christina S.; Rubin, Eric H.; Forde, Patrick M.; Mehnert, Janice M.; Collyar, Deborah; Butler, Marcus O.; Dixon, Erica L.; Chow, Laura Q.M.

2017-01-01

Recent advances in immuno-oncology and regulatory approvals have been rapid and paradigm shifting in many difficult-to-treat malignancies. Despite immune checkpoint inhibitor therapy becoming the standard of care across multiple tumor types, there are many unanswered questions that need to be addressed before this therapeutic modality can be fully harnessed. Areas of limitations include treatment of patients not sufficiently represented in clinical trials, uncertainty of the optimal treatment dosing and duration, and lack of understanding regarding long-term immune related toxicities and atypical tumor responses. Patients such as those with autoimmune disease, chronic viral infections, limited performance status, and brain metastases were often excluded from initial trials due to concerns of safety. However, limited data suggest that some of these patients can benefit from therapy with manageable toxicities; thus, future studies should incorporate these patients to clearly define safety and efficacy. There are still controversies regarding the optimal dosing strategy that can vary from weight-based to flat dosing, with undefined treatment duration. Further elucidation of the optimal dosing approach and evaluation of predictive biomarkers should be incorporated in the design of future trials. Finally, there are long-term immune-mediated toxicities, atypical tumor responses such as pseudoprogression and endpoints unique to immuno-oncology that are not adequately captured by traditional trial designs; thus, novel study designs are needed. In this article, we discuss in detail the above challenges and propose needed areas of research for exploration and incorporation in the next generation of immuno-oncology clinical trials. PMID:28864727

Replay of Episodic Memories in the Rat.

PubMed

Panoz-Brown, Danielle; Iyer, Vishakh; Carey, Lawrence M; Sluka, Christina M; Rajic, Gabriela; Kestenman, Jesse; Gentry, Meredith; Brotheridge, Sydney; Somekh, Isaac; Corbin, Hannah E; Tucker, Kjersten G; Almeida, Bianca; Hex, Severine B; Garcia, Krysten D; Hohmann, Andrea G; Crystal, Jonathon D

2018-05-21

Vivid episodic memories in people have been characterized as the replay of multiple unique events in sequential order [1-3]. The hippocampus plays a critical role in episodic memories in both people and rodents [2, 4-6]. Although rats remember multiple unique episodes [7, 8], it is currently unknown if animals "replay" episodic memories. Therefore, we developed an animal model of episodic memory replay. Here, we show that rats can remember a trial-unique stream of multiple episodes and the order in which these events occurred by engaging hippocampal-dependent episodic memory replay. We document that rats rely on episodic memory replay to remember the order of events rather than relying on non-episodic memories. Replay of episodic memories survives a long retention-interval challenge and interference from the memory of other events, which documents that replay is part of long-term episodic memory. The chemogenetic activating drug clozapine N-oxide (CNO), but not vehicle, reversibly impairs episodic memory replay in rats previously injected bilaterally in the hippocampus with a recombinant viral vector containing an inhibitory designer receptor exclusively activated by a designer drug (DREADD; AAV8-hSyn-hM4Di-mCherry). By contrast, two non-episodic memory assessments are unaffected by CNO, showing selectivity of this hippocampal-dependent impairment. Our approach provides an animal model of episodic memory replay, a process by which the rat searches its representations in episodic memory in sequential order to find information. Our findings using rats suggest that the ability to replay a stream of episodic memories is quite old in the evolutionary timescale. Copyright © 2018 Elsevier Ltd. All rights reserved.

Global analysis of protein folding using massively parallel design, synthesis and testing

PubMed Central

Rocklin, Gabriel J.; Chidyausiku, Tamuka M.; Goreshnik, Inna; Ford, Alex; Houliston, Scott; Lemak, Alexander; Carter, Lauren; Ravichandran, Rashmi; Mulligan, Vikram K.; Chevalier, Aaron; Arrowsmith, Cheryl H.; Baker, David

2017-01-01

Proteins fold into unique native structures stabilized by thousands of weak interactions that collectively overcome the entropic cost of folding. Though these forces are “encoded” in the thousands of known protein structures, “decoding” them is challenging due to the complexity of natural proteins that have evolved for function, not stability. Here we combine computational protein design, next-generation gene synthesis, and a high-throughput protease susceptibility assay to measure folding and stability for over 15,000 de novo designed miniproteins, 1,000 natural proteins, 10,000 point-mutants, and 30,000 negative control sequences, identifying over 2,500 new stable designed proteins in four basic folds. This scale—three orders of magnitude greater than that of previous studies of design or folding—enabled us to systematically examine how sequence determines folding and stability in uncharted protein space. Iteration between design and experiment increased the design success rate from 6% to 47%, produced stable proteins unlike those found in nature for topologies where design was initially unsuccessful, and revealed subtle contributions to stability as designs became increasingly optimized. Our approach achieves the long-standing goal of a tight feedback cycle between computation and experiment, and promises to transform computational protein design into a data-driven science. PMID:28706065

Models of interinstitutional partnerships between research intensive universities and minority serving institutions (MSI) across the Clinical Translational Science Award (CTSA) consortium.

PubMed

Ofili, Elizabeth O; Fair, Alecia; Norris, Keith; Verbalis, Joseph G; Poland, Russell; Bernard, Gordon; Stephens, David S; Dubinett, Steven M; Imperato-McGinley, Julianne; Dottin, Robert P; Pulley, Jill; West, Andrew; Brown, Arleen; Mellman, Thomas A

2013-12-01

Health disparities are an immense challenge to American society. Clinical and Translational Science Awards (CTSAs) housed within the National Center for Advancing Translational Science (NCATS) are designed to accelerate the translation of experimental findings into clinically meaningful practices and bring new therapies to the doorsteps of all patients. Research Centers at Minority Institutions (RCMI) program at the National Institute on Minority Health and Health Disparities (NIMHD) are designed to build capacity for biomedical research and training at minority serving institutions. The CTSA created a mechanism fostering formal collaborations between research intensive universities and minority serving institutions (MSI) supported by the RCMI program. These consortium-level collaborations activate unique translational research approaches to reduce health disparities with credence to each academic institutions history and unique characteristics. Five formal partnerships between research intensive universities and MSI have formed as a result of the CTSA and RCMI programs. These partnerships present a multifocal approach; shifting cultural change and consciousness toward addressing health disparities, and training the next generation of minority scientists. This collaborative model is based on the respective strengths and contributions of the partnering institutions, allowing bidirectional interchange and leveraging NIH and institutional investments providing measurable benchmarks toward the elimination of health disparities. © 2013 Wiley Periodicals, Inc.

Models of Interinstitutional Partnerships between Research Intensive Universities and Minority Serving Institutions (MSI) across the Clinical Translational Science Award (CTSA) Consortium

PubMed Central

Fair, Alecia; Norris, Keith; Verbalis, Joseph G.; Poland, Russell; Bernard, Gordon; Stephens, David S.; Dubinett, Steven M.; Imperato‐McGinley, Julianne; Dottin, Robert P.; Pulley, Jill; West, Andrew; Brown, Arleen; Mellman, Thomas A.

2013-01-01

Abstract Health disparities are an immense challenge to American society. Clinical and Translational Science Awards (CTSAs) housed within the National Center for Advancing Translational Science (NCATS) are designed to accelerate the translation of experimental findings into clinically meaningful practices and bring new therapies to the doorsteps of all patients. Research Centers at Minority Institutions (RCMI) program at the National Institute on Minority Health and Health Disparities (NIMHD) are designed to build capacity for biomedical research and training at minority serving institutions. The CTSA created a mechanism fostering formal collaborations between research intensive universities and minority serving institutions (MSI) supported by the RCMI program. These consortium‐level collaborations activate unique translational research approaches to reduce health disparities with credence to each academic institutions history and unique characteristics. Five formal partnerships between research intensive universities and MSI have formed as a result of the CTSA and RCMI programs. These partnerships present a multifocal approach; shifting cultural change and consciousness toward addressing health disparities, and training the next generation of minority scientists. This collaborative model is based on the respective strengths and contributions of the partnering institutions, allowing bidirectional interchange and leveraging NIH and institutional investments providing measurable benchmarks toward the elimination of health disparities. PMID:24119157

Deep-Ultraviolet Hyperbolic Metacavity Laser.

PubMed

Shen, Kun-Ching; Ku, Chen-Ta; Hsieh, Chiieh; Kuo, Hao-Chung; Cheng, Yuh-Jen; Tsai, Din Ping

2018-05-01

Given the high demand for miniaturized optoelectronic circuits, plasmonic devices with the capability of generating coherent radiation at deep subwavelength scales have attracted great interest for diverse applications such as nanoantennas, single photon sources, and nanosensors. However, the design of such lasing devices remains a challenging issue because of the long structure requirements for producing strong radiation feedback. Here, a plasmonic laser made by using a nanoscale hyperbolic metamaterial cube, called hyperbolic metacavity, on a multiple quantum-well (MQW), deep-ultraviolet emitter is presented. The specifically designed metacavity merges plasmon resonant modes within the cube and provides a unique resonant radiation feedback to the MQW. This unique plasmon field allows the dipoles of the MQW with various orientations into radiative emission, achieving enhancement of spontaneous emission rate by a factor of 33 and of quantum efficiency by a factor of 2.5, which is beneficial for coherent laser action. The hyperbolic metacavity laser shows a clear clamping of spontaneous emission above the threshold, which demonstrates a near complete radiation coupling of the MQW with the metacavity. This approach shown here can greatly simplify the requirements of plasmonic nanolaser with a long plasmonic structure, and the metacavity effect can be extended to many other material systems. © 2018 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

Building and strengthening infrastructure for data exchange: lessons from the beacon communities.

PubMed

Torres, Gretchen W; Swietek, Karen; Ubri, Petry S; Singer, Rachel F; Lowell, Kristina H; Miller, Wilhelmine

2014-01-01

The Beacon Community Cooperative Agreement Program supports interventions, including care-delivery innovations, provider performance measurement and feedback initiatives, and tools for providers and consumers to enhance care. Using a learning health system framework, we examine the Beacon Communities' processes in building and strengthening health IT (HIT) infrastructures, specifically successes and challenges in sharing patient information to improve clinical care. In 2010, the Office of the National Coordinator for Health Information Technology (ONC) launched the three-year program, which provided $250 million to 17 Beacon Communities to invest in HIT and health information exchange (HIE) infrastructure. Beacon Communities used this funding to develop and disseminate HIT-enabled quality improvement practices found effective in particular community and practice environments. NORC conducted 7 site visits, November 2012-March 2013, selecting Communities to represent diverse program features. From August-October 2013, NORC held discussions with the remaining 10 Communities. Following each visit or discussion, NORC summarized the information gathered, including transcripts, team observations, and other documents the Community provided, to facilitate a within-Community analysis of context and stakeholders, intervention strategies, enabling factors, and challenges. Although each Community designed and implemented data-sharing strategies in a unique environment, similar challenges and enabling factors emerged across the Beacons. From a learning health system perspective, their strategies to build and strengthen data-sharing infrastructures address the following crosscutting priorities: promoting technical advances and innovations by helping providers adapt EHRs for data exchange and performance measurement with customizable IT and offering technical support to smaller, independent providers; engaging key stakeholders; and fostering transparent governance and stewardship of the infrastructure with neutral conveners. While all the Communities developed or strengthened data-exchange infrastructure, each did this in a unique environment of existing health care market and legal factors. The Communities, however, encountered similar challenges and enabling factors. Organizations undertaking collaborative data sharing, performance measurement and clinical transformation can learn from the Beacon Communities' experience.

Building and Strengthening Infrastructure for Data Exchange: Lessons from the Beacon Communities

PubMed Central

Torres, Gretchen W.; Swietek, Karen; Ubri, Petry S.; Singer, Rachel F.; Lowell, Kristina H.; Miller, Wilhelmine

2014-01-01

Introduction: The Beacon Community Cooperative Agreement Program supports interventions, including care-delivery innovations, provider performance measurement and feedback initiatives, and tools for providers and consumers to enhance care. Using a learning health system framework, we examine the Beacon Communities’ processes in building and strengthening health IT (HIT) infrastructures, specifically successes and challenges in sharing patient information to improve clinical care. Background: In 2010, the Office of the National Coordinator for Health Information Technology (ONC) launched the three-year program, which provided $250 million to 17 Beacon Communities to invest in HIT and health information exchange (HIE) infrastructure. Beacon Communities used this funding to develop and disseminate HIT-enabled quality improvement practices found effective in particular community and practice environments. Methods: NORC conducted 7 site visits, November 2012–March 2013, selecting Communities to represent diverse program features. From August–October 2013, NORC held discussions with the remaining 10 Communities. Following each visit or discussion, NORC summarized the information gathered, including transcripts, team observations, and other documents the Community provided, to facilitate a within-Community analysis of context and stakeholders, intervention strategies, enabling factors, and challenges. Results: Although each Community designed and implemented data-sharing strategies in a unique environment, similar challenges and enabling factors emerged across the Beacons. From a learning health system perspective, their strategies to build and strengthen data-sharing infrastructures address the following crosscutting priorities: promoting technical advances and innovations by helping providers adapt EHRs for data exchange and performance measurement with customizable IT and offering technical support to smaller, independent providers; engaging key stakeholders; and fostering transparent governance and stewardship of the infrastructure with neutral conveners. Conclusion: While all the Communities developed or strengthened data-exchange infrastructure, each did this in a unique environment of existing health care market and legal factors. The Communities, however, encountered similar challenges and enabling factors. Organizations undertaking collaborative data sharing, performance measurement and clinical transformation can learn from the Beacon Communities’ experience. PMID:25848619

Challenges for Novice School Leaders: Facing Today's Issues in School Administration

ERIC Educational Resources Information Center

Beam, Andrea P.; Claxton, Russell L.; Smith, Samuel J.

2016-01-01

Challenges for novice school leaders evolve as information is managed differently and as societal and regulatory expectations change. This study addresses unique challenges faced by practicing school administrators (n = 159) during their first three years in a school leadership position. It focuses on their perceptions, how perceptions of present…

Showing Your Students You Care: Seeing the Individual Trees in the Classroom Forest

ERIC Educational Resources Information Center

Philipp, Randolph A.; Thanheiser, Eva

2010-01-01

Teaching is a complex profession, and although every context is unique, teachers face common challenges. The authors have identified two challenges that nearly every teacher encounters: (1) managing a classroom of students; and (2) addressing the needs of individual students. Although these are not teachers' only challenges, the authors highlight…

Postsecondary Strengths, Challenges, and Supports Experienced by Foster Care Alumni College Graduates

ERIC Educational Resources Information Center

Salazar, Amy M.; Jones, Kevin R.; Emerson, John C.; Mucha, Lauren

2016-01-01

Young people transitioning from foster care to college experience unique identities and circumstances that make being successful in college especially challenging. We used qualitative survey data from 248 college graduates who were formerly in foster care to explore the strengths, challenges, and supports they experienced while in college that…

Understanding Diversity of English Language Learners: Identification of ELLs and ELLs with Disabilities

ERIC Educational Resources Information Center

Wang, Charity

2014-01-01

English Language Learners (ELLs) are one of the fastest growing student populations throughout the country. With ELLs come unique challenges schools must navigate to best serve these students. One challenge is the identification of these students and proper placement and service within ELL programs offered by schools. Another challenge is…

Ethical Challenges of Military Social Workers Serving in a Combat Zone

ERIC Educational Resources Information Center

Simmons, Catherine A.; Rycraft, Joan R.

2010-01-01

Often faced with ethical challenges that may appear extraordinary, military social workers comprise a distinctive subgroup of the social work profession. From the unique paradigms in which they practice their craft, obvious questions about how military social workers address the ethical challenges inherent to their wartime mission arise. Using a…

NASA Space Flight Vehicle Fault Isolation Challenges

NASA Technical Reports Server (NTRS)

Neeley, James R.; Jones, James V.; Bramon, Christopher J.; Inman, Sharon K.; Tuttle, Loraine

2016-01-01

The Space Launch System (SLS) is the new NASA heavy lift launch vehicle in development and is scheduled for its first mission in 2018.SLS has many of the same logistics challenges as any other large scale program. However, SLS also faces unique challenges related to testability. This presentation will address the SLS challenges for diagnostics and fault isolation, along with the analyses and decisions to mitigate risk..

Design and Evaluation in eHealth: Challenges and Implications for an Interdisciplinary Field

PubMed Central

2007-01-01

Much has been written about insufficient user involvement in the design of eHealth applications, the lack of evidence demonstrating impact, and the difficulties these bring for adoption. Part of the problem lies in the differing languages, cultures, motives, and operational constraints of producers and evaluators of eHealth systems and services. This paper reflects on the benefits of and barriers to interdisciplinary collaboration in eHealth, focusing particularly on the relationship between software developers and health services researchers. It argues that the common pattern of silo or parallel working may be ameliorated by developing mutual awareness and respect for each others’ methods, epistemologies, and contextual drivers and by recognizing and harnessing potential synergies. Similarities and differences between models and techniques used in both communities are highlighted in order to illustrate the potential for integrated approaches and the strengths of unique paradigms. By sharing information about our research approaches and seeking to actively collaborate in the process of design and evaluation, the aim of achieving technologies that are truly user-informed, fit for context, high quality, and of demonstrated value is more likely to be realized. This may involve embracing new ways of working jointly that are unfamiliar to the stakeholders involved and that challenge disciplinary conventions. It also has policy implications for agencies commissioning research and development in this area. PMID:17537718

mIoT Slice for 5G Systems: Design and Performance Evaluation

PubMed Central

Condoluci, Massimo; An, Xueli

2018-01-01

Network slicing is a key feature of the upcoming 5G networks allowing the design and deployment of customized communication systems to integrate services provided by vertical industries. In this context, massive Internet of Things (mIoT) is regarded as a compelling use case, both for its relevance from business perspective, and for the technical challenges it poses to network design. With their envisaged massive deployment of devices requiring sporadic connectivity and small data transmission, yet Quality of Service (QoS) constrained, mIoT services will need an ad-hoc end-to-end (E2E) slice, i.e., both access and core network with enhanced Control and User planes (CP/UP). After revising the key requirements of mIoT and identifying major shortcomings of previous generation networks, this paper presents and evaluates an E2E mIoT network slicing solution, featuring a new connectivity model overcoming the load limitations of legacy systems. Unique in its kind, this paper addresses mIoT requirements from an end-to-end perspective highlighting and solving, unlike most prior related work, the connectivity challenges posed to the core network. Results demonstrate that the proposed solution, reducing CP signaling and optimizing UP resource utilization, is a suitable candidate for next generation network standards to efficiently handle massive device deployment. PMID:29466311

mIoT Slice for 5G Systems: Design and Performance Evaluation.

PubMed

Trivisonno, Riccardo; Condoluci, Massimo; An, Xueli; Mahmoodi, Toktam

2018-02-21

Network slicing is a key feature of the upcoming 5G networks allowing the design and deployment of customized communication systems to integrate services provided by vertical industries. In this context, massive Internet of Things (mIoT) is regarded as a compelling use case, both for its relevance from business perspective, and for the technical challenges it poses to network design. With their envisaged massive deployment of devices requiring sporadic connectivity and small data transmission, yet Quality of Service (QoS) constrained, mIoT services will need an ad-hoc end-to-end (E2E) slice, i.e., both access and core network with enhanced Control and User planes (CP/UP). After revising the key requirements of mIoT and identifying major shortcomings of previous generation networks, this paper presents and evaluates an E2E mIoT network slicing solution, featuring a new connectivity model overcoming the load limitations of legacy systems. Unique in its kind, this paper addresses mIoT requirements from an end-to-end perspective highlighting and solving, unlike most prior related work, the connectivity challenges posed to the core network. Results demonstrate that the proposed solution, reducing CP signaling and optimizing UP resource utilization, is a suitable candidate for next generation network standards to efficiently handle massive device deployment.

Unique research challenges for high-speed civil transports

NASA Technical Reports Server (NTRS)

Jackson, Charlie M., Jr.; Morris, E. K., Jr.

1988-01-01

Market growth and technological advances are expected to lead to a generation of long-range transports that cruise at supersonic or even hypersonic speeds. Current NASA/industry studies will define the market windows in terms of time frame, Mach number, and technology requirements for these aircraft. Initial results indicate that, for the years 2000 to 2020, economically attractive vehicles could have a cruise speed up to Mach 6. The resulting research challenges are unique. They must be met with technologies that will produce commercially successful and environmentally compatible vehicles where none have existed. Several important areas of research were identified for the high-speed civil transports. Among these are sonic boom, takeoff noise, thermal management, lightweight structures with long life, unique propulsion concepts, unconventional fuels, and supersonic laminar flow.

Unique research challenges for high-speed civil transports

NASA Technical Reports Server (NTRS)

Jackson, Charlie M., Jr.; Morris, Charles E. K., Jr.

1987-01-01

Market growth and technological advances are expected to lead to a generation of long-range transports that cruise at supersonic or even hypersonic speeds. Current NASA/industry studies will define the market windows in terms of time frame, Mach number, and technology requirements for these aircraft. Initial results indicate that, for the years 2000 to 2020, economically attractive vehicles could have a cruise speed up to Mach 6. The resulting research challenges are unique. They must be met with technologies that will produce commercially successful and environmentally compatible vehicles where none have existed. Several important areas of research were identified for the high-speed civil transports. Among these are sonic boom, takeoff noise, thermal management, lightweight structures with long life, unique propulsion concepts, unconventional fuels, and supersonic laminar flow.

Resilient and Corrosion-proof Rolling Element Bearings Made from Ni-ti Alloys for Aerospace Mechanism Applications and the Ultimate Space Technology Development Platform

NASA Technical Reports Server (NTRS)

Dellacorte, Christopher

2014-01-01

The International Space Station provides a unique microgravity laboratory environment for research. The ISS also serves as an effective platform for the development of technologies and engineered solutions related to living and working in space. The space environment also challenges our capabilities related to lubrication and tribology. In this seminar, Dr. DellaCorte will review the basics of space mechanism tribology and the challenges of providing good lubrication and long-life in the harsh space environment. He will also discuss recent tribological challenges associated with the Solar Alpha Rotary Joint (SARJ) bearings and life support hardware that must operate under severe conditions that are literally out of this world. Each tribology challenge is unique and their solutions often result in new technologies that benefit the tribology community everywhere, even back on Earth

Promises and challenges in solid-state lighting

NASA Astrophysics Data System (ADS)

Schubert, Fred

2010-03-01

Lighting technologies based on semiconductor light-emitting diodes (LEDs) offer unprecedented promises that include three major benefits: (i) Gigantic energy savings enabled by efficient conversion of electrical energy to optical energy; (ii) Substantial positive contributions to sustainability through reduced emissions of global-warming gases, acid-rain gases, and toxic substances such as mercury; and (iii) The creation of new paradigms in lighting driven by the unique controllability of solid-state lighting sources. Due to the powerful nature of these benefits, the transition from conventional lighting sources to solid-state lighting is virtually assured. This presentation will illustrate the new world of lighting and illustrate the pervasive changes to be expected in lighting, displays, communications, and biotechnology. The presentation will also address the formidable challenges that must be addressed to continue the further advancement of solid-state lighting technology. These challenges offer opportunities for research and innovation. Specific challenges include light management, carrier transport, and optical design. We will present some innovative approaches in order to solve known technical challenges faced by solid-state lighting. These approaches include the demonstration and use of new optical thin-film materials with a continuously tunable refractive index. These approaches also include the use of polarization-matched structures that reduce the polarization fields in GaInN LEDs and the hotly debated efficiency droop, that is, the decreasing LED efficiency at high currents.

The art of spacecraft design: A multidisciplinary challenge

NASA Technical Reports Server (NTRS)

Abdi, F.; Ide, H.; Levine, M.; Austel, L.

1989-01-01

Actual design turn-around time has become shorter due to the use of optimization techniques which have been introduced into the design process. It seems that what, how and when to use these optimization techniques may be the key factor for future aircraft engineering operations. Another important aspect of this technique is that complex physical phenomena can be modeled by a simple mathematical equation. The new powerful multilevel methodology reduces time-consuming analysis significantly while maintaining the coupling effects. This simultaneous analysis method stems from the implicit function theorem and system sensitivity derivatives of input variables. Use of the Taylor's series expansion and finite differencing technique for sensitivity derivatives in each discipline makes this approach unique for screening dominant variables from nondominant variables. In this study, the current Computational Fluid Dynamics (CFD) aerodynamic and sensitivity derivative/optimization techniques are applied for a simple cone-type forebody of a high-speed vehicle configuration to understand basic aerodynamic/structure interaction in a hypersonic flight condition.

Validation of Autoclave Protocols for Successful Decontamination of Category A Medical Waste Generated from Care of Patients with Serious Communicable Diseases

PubMed Central

Reimers, Mallory; Ernst, Neysa; Bova, Gregory; Nowakowski, Elaine; Bukowski, James; Ellis, Brandon C.; Smith, Chris; Sauer, Lauren; Dionne, Kim; Carroll, Karen C.; Maragakis, Lisa L.; Parrish, Nicole M.

2016-01-01

ABSTRACT In response to the Ebola outbreak in 2014, many hospitals designated specific areas to care for patients with Ebola and other highly infectious diseases. The safe handling of category A infectious substances is a unique challenge in this environment. One solution is on-site waste treatment with a steam sterilizer or autoclave. The Johns Hopkins Hospital (JHH) installed two pass-through autoclaves in its biocontainment unit (BCU). The JHH BCU and The Johns Hopkins biosafety level 3 (BSL-3) clinical microbiology laboratory designed and validated waste-handling protocols with simulated patient trash to ensure adequate sterilization. The results of the validation process revealed that autoclave factory default settings are potentially ineffective for certain types of medical waste and highlighted the critical role of waste packaging in successful sterilization. The lessons learned from the JHH validation process can inform the design of waste management protocols to ensure effective treatment of highly infectious medical waste. PMID:27927920

Assessing college-level learning difficulties and "at riskness" for learning disabilities and ADHD: development and validation of the learning difficulties assessment.

PubMed

Kane, Steven T; Walker, John H; Schmidt, George R

2011-01-01

This article describes the development and validation of the Learning Difficulties Assessment (LDA), a normed and web-based survey that assesses perceived difficulties with reading, writing, spelling, mathematics, listening, concentration, memory, organizational skills, sense of control, and anxiety in college students. The LDA is designed to (a) map individual learning strengths and weaknesses, (b) provide users with a comparative sense of their academic skills, (c) integrate research in user-interface design to assist those with reading and learning challenges, and (d) identify individuals who may be at risk for learning disabilities and attention-deficit/hyperactivity disorder (ADHD) and who should thus be further assessed. Data from a large-scale 5-year study describing the instrument's validity as a screening tool for learning disabilities and ADHD are presented. This article also describes unique characteristics of the LDA including its user-interface design, normative characteristics, and use as a no-cost screening tool for identifying college students at risk for learning disorders and ADHD.

Designing multifunctional quantum dots for bioimaging, detection, and drug delivery

PubMed Central

Zrazhevskiy, Pavel; Sena, Mark; Gao, Xiaohu

2011-01-01

The emerging field of bionanotechnology aims at revolutionizing biomedical research and clinical practice via introduction of nanoparticle-based tools, expanding capabilities of existing investigative, diagnostic, and therapeutic techniques as well as creating novel instruments and approaches for addressing challenges faced by medicine. Quantum dots (QDs), semiconductor nanoparticles with unique photo-physical properties, have become one of the dominant classes of imaging probes as well as universal platforms for engineering of multifunctional nanodevices. Possessing versatile surface chemistry and superior optical features, QDs have found initial use in a variety of in vitro and in vivo applications. However, careful engineering of QD probes guided by application-specific design criteria is becoming increasingly important for successful transition of this technology from proof-of-concept studies towards real-life clinical applications. This review outlines the major design principles and criteria, from general ones to application-specific, governing the engineering of novel QD probes satisfying the increasing demands and requirements of nanomedicine and discusses the future directions of QD-focused bionanotechnology research (critical review, 201 references). PMID:20697629

Design of pressure-driven microfluidic networks using electric circuit analogy.

PubMed

Oh, Kwang W; Lee, Kangsun; Ahn, Byungwook; Furlani, Edward P

2012-02-07

This article reviews the application of electric circuit methods for the analysis of pressure-driven microfluidic networks with an emphasis on concentration- and flow-dependent systems. The application of circuit methods to microfluidics is based on the analogous behaviour of hydraulic and electric circuits with correlations of pressure to voltage, volumetric flow rate to current, and hydraulic to electric resistance. Circuit analysis enables rapid predictions of pressure-driven laminar flow in microchannels and is very useful for designing complex microfluidic networks in advance of fabrication. This article provides a comprehensive overview of the physics of pressure-driven laminar flow, the formal analogy between electric and hydraulic circuits, applications of circuit theory to microfluidic network-based devices, recent development and applications of concentration- and flow-dependent microfluidic networks, and promising future applications. The lab-on-a-chip (LOC) and microfluidics community will gain insightful ideas and practical design strategies for developing unique microfluidic network-based devices to address a broad range of biological, chemical, pharmaceutical, and other scientific and technical challenges.

Fluid dynamic characteristics of the VentrAssist rotary blood pump.

PubMed

Tansley, G; Vidakovic, S; Reizes, J

2000-06-01

The VentrAssist pump has no shaft or seal, and the device is unique in design because the rotor is suspended passively by hydrodynamic forces, and urging is accomplished by an integrated direct current motor rotor that also acts as the pump impeller. This device has led to many challenges in its fluidic design, namely large flow-blockage from impeller blades, low stiffness of bearings with concomitant impeller displacement under pulsatile load conditions, and very small running clearances. Low specific speed and radial blade off-flow were selected in order to minimize the hemolysis. Pulsatile and steady-flow tests show the impeller is stable under normal operating conditions. Computational fluid dynamics (CFD) has been used to optimize flow paths and reduce net axial force imbalance to acceptably small values. The latest design of the pump achieved a system efficiency of 18% (in 30% hematocrit of red blood cells suspended in phosphate-buffered saline), and efficiency was optimized over the range of operating conditions. Parameters critical to improving pump efficiency were investigated.

Coproduction of healthcare service.

PubMed

Batalden, Maren; Batalden, Paul; Margolis, Peter; Seid, Michael; Armstrong, Gail; Opipari-Arrigan, Lisa; Hartung, Hans

2016-07-01

Efforts to ensure effective participation of patients in healthcare are called by many names-patient centredness, patient engagement, patient experience. Improvement initiatives in this domain often resemble the efforts of manufacturers to engage consumers in designing and marketing products. Services, however, are fundamentally different than products; unlike goods, services are always 'coproduced'. Failure to recognise this unique character of a service and its implications may limit our success in partnering with patients to improve health care. We trace a partial history of the coproduction concept, present a model of healthcare service coproduction and explore its application as a design principle in three healthcare service delivery innovations. We use the principle to examine the roles, relationships and aims of this interdependent work. We explore the principle's implications and challenges for health professional development, for service delivery system design and for understanding and measuring benefit in healthcare services. Published by the BMJ Publishing Group Limited. For permission to use (where not already granted under a licence) please go to http://www.bmj.com/company/products-services/rights-and-licensing/

Innovative ventilation system for animal anatomy laboratory

DOE Office of Scientific and Technical Information (OSTI.GOV)

Lacey, D.R.; Smith, D.C.

1997-04-01

A unique ventilation system was designed and built to reduce formaldehyde fumes in the large animal anatomy lab at the Vet Medical Center at Cornell University. The laboratory includes four rooms totaling 5,500 ft{sup 2}. The main room has 2,300 ft{sup 2} and houses the laboratory where up to 60 students dissect as many as 12 horses at a time. Other rooms are a cold storage locker, an animal preparation room and a smaller lab for specialized instruction. The large animal anatomy laboratory has a history of air quality complaints despite a fairly high ventilation rate of over 10 airmore » changes/hour. The horses are embalmed, creating a voluminous source of formaldehyde and phenol vapors. Budget constraints and increasingly stringent exposure limits for formaldehyde presented a great challenge to design a ventilation system that yields acceptable air quality. The design solution included two innovative elements: air-to-air heat recovery, and focused ventilation.« less

Whirl Flutter Studies for a SSTOL Transport Demonstrator

NASA Technical Reports Server (NTRS)

Acree, C. W., Jr.; Hoffman, Krishna

2004-01-01

A proposed new class of aircraft - the Advanced Theater Transport (ATT) will combine strategic range and high payload with 'Super-STOL' (short take-off and landing) capability. It is also proposed to modify a YC-15 into a technology demonstrator with a 20-deg tilt wing; four, eight-bladed propellers; cross-shafted gearboxes and V-22 engines. These constitute a unique combination of design features that potentially affect performance, loads and whirl-mode stability (whirl flutter). NASA Ames Research Center is working with Boeing and Hamilton Sundstrand on technology challenges presented by the concept; the purpose of NASA involvement is to establish requirements for the demonstrator and for early design guidance, with emphasis on whirl flutter. CAMRAD II is being used to study the effects of various design features on whirl flutter, with special attention to areas where such features differ from existing aircraft, notably tiltrotors. Although the stability margins appear to be more than adequate, the concept requires significantly different analytical methods, principally including far more blade modes, than typically used for tiltrotors.

Design of Architectures and Materials in In-Plane Micro-supercapacitors: Current Status and Future Challenges.

PubMed

Qi, Dianpeng; Liu, Yan; Liu, Zhiyuan; Zhang, Li; Chen, Xiaodong

2017-02-01

The rapid development of integrated electronics and the boom in miniaturized and portable devices have increased the demand for miniaturized and on-chip energy storage units. Currently thin-film batteries or microsized batteries are commercially available for miniaturized devices. However, they still suffer from several limitations, such as short lifetime, low power density, and complex architecture, which limit their integration. Supercapacitors can surmount all these limitations. Particularly for micro-supercapacitors with planar architectures, due to their unique design of the in-plane electrode finger arrays, they possess the merits of easy fabrication and integration into on-chip miniaturized electronics. Here, the focus is on the different strategies to design electrode finger arrays and the material engineering of in-plane micro-supercapacitors. It is expected that the advances in micro-supercapacitors with in-plane architectures will offer new opportunities for the miniaturization and integration of energy-storage units for portable devices and on-chip electronics. © 2016 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.