Strategies to improve learning of all students in a class
NASA Astrophysics Data System (ADS)
Suraishkumar, G. K.
2018-05-01
The statistical distribution of the student learning abilities in a typical undergraduate engineering class poses a significant challenge to simultaneously improve the learning of all the students in the class. With traditional instruction styles, the students with significantly high learning abilities are not satisfied due to a feeling of unfulfilled potential, and the students with significantly low learning abilities feel lost. To address the challenge in an undergraduate core/required course on 'transport phenomena in biological systems', a combination of learning strategies such as active learning including co-operative group learning, challenge exercises, and others were employed in a pro-advising context. The short-term and long-term impacts were evaluated through student course performances and input, respectively. The results show that it is possible to effectively address the challenge posed by the distribution of student learning abilities in a class.
Combining in silico and in cerebro approaches for virtual screening and pose prediction in SAMPL4.
Voet, Arnout R D; Kumar, Ashutosh; Berenger, Francois; Zhang, Kam Y J
2014-04-01
The SAMPL challenges provide an ideal opportunity for unbiased evaluation and comparison of different approaches used in computational drug design. During the fourth round of this SAMPL challenge, we participated in the virtual screening and binding pose prediction on inhibitors targeting the HIV-1 integrase enzyme. For virtual screening, we used well known and widely used in silico methods combined with personal in cerebro insights and experience. Regular docking only performed slightly better than random selection, but the performance was significantly improved upon incorporation of additional filters based on pharmacophore queries and electrostatic similarities. The best performance was achieved when logical selection was added. For the pose prediction, we utilized a similar consensus approach that amalgamated the results of the Glide-XP docking with structural knowledge and rescoring. The pose prediction results revealed that docking displayed reasonable performance in predicting the binding poses. However, prediction performance can be improved utilizing scientific experience and rescoring approaches. In both the virtual screening and pose prediction challenges, the top performance was achieved by our approaches. Here we describe the methods and strategies used in our approaches and discuss the rationale of their performances.
Combining in silico and in cerebro approaches for virtual screening and pose prediction in SAMPL4
NASA Astrophysics Data System (ADS)
Voet, Arnout R. D.; Kumar, Ashutosh; Berenger, Francois; Zhang, Kam Y. J.
2014-04-01
The SAMPL challenges provide an ideal opportunity for unbiased evaluation and comparison of different approaches used in computational drug design. During the fourth round of this SAMPL challenge, we participated in the virtual screening and binding pose prediction on inhibitors targeting the HIV-1 integrase enzyme. For virtual screening, we used well known and widely used in silico methods combined with personal in cerebro insights and experience. Regular docking only performed slightly better than random selection, but the performance was significantly improved upon incorporation of additional filters based on pharmacophore queries and electrostatic similarities. The best performance was achieved when logical selection was added. For the pose prediction, we utilized a similar consensus approach that amalgamated the results of the Glide-XP docking with structural knowledge and rescoring. The pose prediction results revealed that docking displayed reasonable performance in predicting the binding poses. However, prediction performance can be improved utilizing scientific experience and rescoring approaches. In both the virtual screening and pose prediction challenges, the top performance was achieved by our approaches. Here we describe the methods and strategies used in our approaches and discuss the rationale of their performances.
NASA Astrophysics Data System (ADS)
Baumgartner, Matthew P.; Evans, David A.
2018-01-01
Two of the major ongoing challenges in computational drug discovery are predicting the binding pose and affinity of a compound to a protein. The Drug Design Data Resource Grand Challenge 2 was developed to address these problems and to drive development of new methods. The challenge provided the 2D structures of compounds for which the organizers help blinded data in the form of 35 X-ray crystal structures and 102 binding affinity measurements and challenged participants to predict the binding pose and affinity of the compounds. We tested a number of pose prediction methods as part of the challenge; we found that docking methods that incorporate protein flexibility (Induced Fit Docking) outperformed methods that treated the protein as rigid. We also found that using binding pose metadynamics, a molecular dynamics based method, to score docked poses provided the best predictions of our methods with an average RMSD of 2.01 Å. We tested both structure-based (e.g. docking) and ligand-based methods (e.g. QSAR) in the affinity prediction portion of the competition. We found that our structure-based methods based on docking with Smina (Spearman ρ = 0.614), performed slightly better than our ligand-based methods (ρ = 0.543), and had equivalent performance with the other top methods in the competition. Despite the overall good performance of our methods in comparison to other participants in the challenge, there exists significant room for improvement especially in cases such as these where protein flexibility plays such a large role.
THE DNAPL REMEDIATION CHALLENGE: IS THERE A CASE FOR SOURCE DEPLETION?
Releases of Dense Non-Aqueous Phase Liquids (DNAPLs) at a large number of public and private sector sites in the United States pose significant challenges in site remediation and long-term site management. Extensive contamination of groundwater occurs as a result of significant ...
Challenges of Conducting Research With Young Offenders With Traumatic Brain Injury.
OʼRourke, Conall; Templeton, Michelle; Cohen, Miriam H; Linden, Mark A
2018-05-31
The purpose of this commentary is to highlight the challenges encountered when conducting research with young offenders. This is drawn from the first-hand experience of 3 researchers working on separate projects within this environment. Young offenders present as a complex clinical population with high levels of illiteracy, substance abuse, and mental health issues. Significant planning is therefore required before working with this group. Consideration must be given to the heterogeneity of prison populations alongside the potential limitations of datacollection methods, in particular, reliance on self-report. The capacity of young offenders to comprehend and effectively engage with research is also of concern, posing issues of both a practical and ethical nature. The absence of a consistent "research culture" within prison environments poses further practical challenges, potentially also placing significant burden on both researchers and prison resources. The challenges discussed in this article may help inform future studies in the area and emphasize the need for greater critical reflection among researchers conducting work of this type.
ERIC Educational Resources Information Center
Novis-Deutsch, Nurit; Lifshitz, Chen
2016-01-01
The integration of highly religious minority students into institutions of higher education poses significant pedagogical and value challenges for students and teachers alike. We offer a framework for analyzing such challenges, distinguishing between practical concerns, identity issues and value conflicts. By contrasting a deficit perspective to…
Bisphenol A and Risk Management Ethics
Resnik, David B.; Elliot, Kevin C.
2013-01-01
It is widely recognized that endocrine disrupting compounds, such as Bisphenol A, pose challenges for traditional paradigms in toxicology, insofar as these substances appear to have a wider range of low-dose effects than previously recognized. These compounds also pose challenges for ethics and policymaking. When a chemical does not have significant low-dose effects, regulators can allow it to be introduced into commerce or the environment, provided that procedures and rules are in place to keep exposures below an acceptable level. This option allows society to maximize the benefits from the use of the chemical while minimizing risks to human health or the environment, and it represents a compromise between competing values. When it is not possible to establish acceptable exposure levels for chemicals that pose significant health or environmental risks, the most reasonable options for risk management may be to enact either partial or complete bans on their use. These options create greater moral conflict than other risk management strategies, leaving policymakers difficult choices between competing values. PMID:24471646
Bisphenol A and risk management ethics.
Resnik, David B; Elliott, Kevin C
2015-03-01
It is widely recognized that endocrine disrupting compounds, such as Bisphenol A, pose challenges for traditional paradigms in toxicology, insofar as these substances appear to have a wider range of low-dose effects than previously recognized. These compounds also pose challenges for ethics and policymaking. When a chemical does not have significant low-dose effects, regulators can allow it to be introduced into commerce or the environment, provided that procedures and rules are in place to keep exposures below an acceptable level. This option allows society to maximize the benefits from the use of the chemical while minimizing risks to human health or the environment, and it represents a compromise between competing values. When it is not possible to establish acceptable exposure levels for chemicals that pose significant health or environmental risks, the most reasonable options for risk management may be to enact either partial or complete bans on their use. These options create greater moral conflict than other risk management strategies, leaving policymakers difficult choices between competing values. © 2014 John Wiley & Sons Ltd.
NASA Astrophysics Data System (ADS)
Fradera, Xavier; Verras, Andreas; Hu, Yuan; Wang, Deping; Wang, Hongwu; Fells, James I.; Armacost, Kira A.; Crespo, Alejandro; Sherborne, Brad; Wang, Huijun; Peng, Zhengwei; Gao, Ying-Duo
2018-01-01
We describe the performance of multiple pose prediction methods for the D3R 2016 Grand Challenge. The pose prediction challenge includes 36 ligands, which represent 4 chemotypes and some miscellaneous structures against the FXR ligand binding domain. In this study we use a mix of fully automated methods as well as human-guided methods with considerations of both the challenge data and publicly available data. The methods include ensemble docking, colony entropy pose prediction, target selection by molecular similarity, molecular dynamics guided pose refinement, and pose selection by visual inspection. We evaluated the success of our predictions by method, chemotype, and relevance of publicly available data. For the overall data set, ensemble docking, visual inspection, and molecular dynamics guided pose prediction performed the best with overall mean RMSDs of 2.4, 2.2, and 2.2 Å respectively. For several individual challenge molecules, the best performing method is evaluated in light of that particular ligand. We also describe the protein, ligand, and public information data preparations that are typical of our binding mode prediction workflow.
Intelligent Tutoring Systems for Literacy: Existing Technologies and Continuing Challenges
ERIC Educational Resources Information Center
Jacovina, Matthew E.; McNamara, Danielle S.
2017-01-01
In this chapter, we describe several intelligent tutoring systems (ITSs) designed to support student literacy through reading comprehension and writing instruction and practice. Although adaptive instruction can be a powerful tool in the literacy domain, developing these technologies poses significant challenges. For example, evaluating the…
Single leg balancing in ballet: effects of shoe conditions and poses.
Lobo da Costa, Paula H; Azevedo Nora, Fernanda G S; Vieira, Marcus Fraga; Bosch, Kerstin; Rosenbaum, Dieter
2013-03-01
The purpose of this study was to describe the effects of lower limb positioning and shoe conditions on stability levels of selected single leg ballet poses performed in demi-pointe position. Fourteen female non-professional ballet dancers (mean age of 18.4±2.8 years and mean body mass index of 21.5±2.8kg/m(2)) who had practiced ballet for at least seven years, without any musculoskeletal impairment volunteered to participate in this study. A capacitive pressure platform allowed for the assessment of center of pressure variables related to the execution of three single leg ballet poses in demi pointé position: attitude devant, attitude derriére, and attitude a la second. Peak pressures, contact areas, COP oscillation areas, anterior-posterior and medio-lateral COP oscillations and velocities were compared between two shoe conditions (barefoot versus slippers) and among the different poses. Barefoot performances produced more stable poses with significantly higher plantar contact areas, smaller COP oscillation areas and smaller anterior-posterior COP oscillations. COP oscillation areas, anterior-posterior COP oscillations and medio-lateral COP velocities indicated that attitude a la second is the least challenging and attitude derriére the most challenging pose. Copyright © 2012 Elsevier B.V. All rights reserved.
Obstacles facing Africa's young climate scientists
NASA Astrophysics Data System (ADS)
Dike, Victor Nnamdi; Addi, Martin; Andang'o, Hezron Awiti; Attig, Bahar Faten; Barimalala, Rondrotiana; Diasso, Ulrich Jacques; Du Plessis, Marcel; Lamine, Salim; Mongwe, Precious N.; Zaroug, Modathir; Ochanda, Valentine Khasenye
2018-06-01
Current and future climate change poses a substantial threat to the African continent. Young scientists are needed to advance Earth systems science on the continent, but they face significant challenges.
Calibrated Methodology for Assessing Adaptation Costs for Urban Drainage Systems
Changes in precipitation patterns associated with climate change may pose significant challenges for storm water management systems across much of the U.S. In particular, adapting these systems to more intense rainfall events will require significant investment. The assessment ...
A study on facial expressions recognition
NASA Astrophysics Data System (ADS)
Xu, Jingjing
2017-09-01
In terms of communication, postures and facial expressions of such feelings like happiness, anger and sadness play important roles in conveying information. With the development of the technology, recently a number of algorithms dealing with face alignment, face landmark detection, classification, facial landmark localization and pose estimation have been put forward. However, there are a lot of challenges and problems need to be fixed. In this paper, a few technologies have been concluded and analyzed, and they all relate to handling facial expressions recognition and poses like pose-indexed based multi-view method for face alignment, robust facial landmark detection under significant head pose and occlusion, partitioning the input domain for classification, robust statistics face formalization.
Experimental Evidence for Diagramming Benefits in Science Writing
ERIC Educational Resources Information Center
Barstow, Brendan; Fazio, Lisa; Schunn, Christian; Ashley, Kevin
2017-01-01
Arguing for the need for a scientific research study (i.e. writing an introduction to a research paper) poses significant challenges for students. When faced with these challenges, students often generate overly safe replications (i.e. fail to find and include opposition to their hypothesis) or in contrast include no strong support for their…
Investigating Factors Affecting Group Processes in Virtual Learning Environments
ERIC Educational Resources Information Center
Hazari, Sunil; Thompson, Sandra
2015-01-01
With the widespread popularity of distance learning, there is a need to investigate elements of online courses that continue to pose significant challenges for educators. One of the challenges relates to creating and managing group projects. This study investigated business students' perceptions of group work in online classes. The constructs of…
Planning the future's forests with assisted migration
Mary I. Williams; R. Kasten Dumroese
2014-01-01
Studies show that changes in climate may exceed plant adaptation and migration. The mismatch in rates between climate change and plant adaptation and migration will pose significant challenges for practitioners that select, grow, and outplant native tree species. Native tree species and populations that are planted today must meet the climatic challenges that they will...
Muslim Learners in English Schools: A Challenge for School Leaders
ERIC Educational Resources Information Center
Shah, Saeeda
2009-01-01
Faith identity is emerging as significant for Muslim students in the post 9/11 scenario, with implications for their education and wider social cohesion. This poses challenges to school leaders, raising issues not only linked to student achievement and performance, but also with regard to students' identity constructions and their educational…
NASA Astrophysics Data System (ADS)
Athanasiou, Christina; Vasilakaki, Sofia; Dellis, Dimitris; Cournia, Zoe
2018-01-01
Computer-aided drug design has become an integral part of drug discovery and development in the pharmaceutical and biotechnology industry, and is nowadays extensively used in the lead identification and lead optimization phases. The drug design data resource (D3R) organizes challenges against blinded experimental data to prospectively test computational methodologies as an opportunity for improved methods and algorithms to emerge. We participated in Grand Challenge 2 to predict the crystallographic poses of 36 Farnesoid X Receptor (FXR)-bound ligands and the relative binding affinities for two designated subsets of 18 and 15 FXR-bound ligands. Here, we present our methodology for pose and affinity predictions and its evaluation after the release of the experimental data. For predicting the crystallographic poses, we used docking and physics-based pose prediction methods guided by the binding poses of native ligands. For FXR ligands with known chemotypes in the PDB, we accurately predicted their binding modes, while for those with unknown chemotypes the predictions were more challenging. Our group ranked #1st (based on the median RMSD) out of 46 groups, which submitted complete entries for the binding pose prediction challenge. For the relative binding affinity prediction challenge, we performed free energy perturbation (FEP) calculations coupled with molecular dynamics (MD) simulations. FEP/MD calculations displayed a high success rate in identifying compounds with better or worse binding affinity than the reference (parent) compound. Our studies suggest that when ligands with chemical precedent are available in the literature, binding pose predictions using docking and physics-based methods are reliable; however, predictions are challenging for ligands with completely unknown chemotypes. We also show that FEP/MD calculations hold predictive value and can nowadays be used in a high throughput mode in a lead optimization project provided that crystal structures of sufficiently high quality are available.
Nutrient removal of agricultural drainage water using algal turf scrubbers and solar power
USDA-ARS?s Scientific Manuscript database
Restoration of the Chesapeake Bay poses significant challenges because of increasing population pressure, conversion of farmland to urban/suburban development, and the expense of infrastructure needed to achieve significant and sustained nutrient reductions from agricultural and urban sources. One ...
Addressing elderly mobility issues in Wisconsin.
DOT National Transportation Integrated Search
2011-09-01
The aging of baby boomers poses significant challenges to Wisconsins existing transportation infrastructure and specialized transit : programs. From 2010 to 2035, the number of elderly Wisconsinites is projected to grow by 90 percent, an increase ...
Addressing elderly mobility issues in Wisconsin.
DOT National Transportation Integrated Search
2011-09-01
"The aging of baby boomers poses significant challenges to Wisconsins existing transportation infrastructure and specialized transit : programs. From 2010 to 2035, the number of elderly Wisconsinites is projected to grow by 90 percent, an increase...
Assisted migration: What it means to nursery managers and tree planters
Mary I. Williams; R. Kasten Dumroese
2014-01-01
Projections indicate that natural plant adaptation and migration may not keep pace with climate changes. This mismatch in rates will pose significant challenges for practitioners that select, grow, and outplant native tree species. Populations of native tree species planted today must be able to meet the climatic challenges they will face during this century. One...
ERIC Educational Resources Information Center
Jackson, Denise; Rowbottom, David; Ferns, Sonia; McLaren, Diane
2017-01-01
This study examines employer understanding of Work-Integrated Learning (WIL), reasons for participation and the challenges and barriers posed during the WIL process. This is important given the drive to grow WIL, augmented by the National Strategy for WIL, and the significant benefits it holds in preparing students for their transition to…
Separating the Wheat from the Chaff: Identifying Key Elements in the NLA .AU Domain Harvest
ERIC Educational Resources Information Center
Fellows, Geoff; Harvey, Ross; Lloyd, Annemaree; Pymm, Bob; Wallis, Jake
2008-01-01
In 2005 and 2006 the National Library of Australia (NLA) carried out two whole-domain web harvests which complement the selective web archiving approach taken by PANDORA. Web harvests of this size pose significant challenges to their use. Despite these challenges, such harvests present fascinating research opportunities. The NLA has provided…
Challenges and Induction Needs of Novice English as a Foreign Language Teachers in Saudi Arabia
ERIC Educational Resources Information Center
Alhamad, Rufaida
2018-01-01
The first year of teaching poses massive challenges that lead to attrition among novice teachers. School communities often fail to provide adequate support to novice teachers to help them adapt to their new professional environments. In Saudi Arabia, attrition among novice teachers is a significant problem that hinders the development of the…
NASA Astrophysics Data System (ADS)
Opromolla, Roberto; Fasano, Giancarmine; Rufino, Giancarlo; Grassi, Michele
2017-08-01
The capability of an active spacecraft to accurately estimate its relative position and attitude (pose) with respect to an active/inactive, artificial/natural space object (target) orbiting in close-proximity is required to carry out various activities like formation flying, on-orbit servicing, active debris removal, and space exploration. According to the specific mission scenario, the pose determination task involves both theoretical and technological challenges related to the search for the most suitable algorithmic solution and sensor architecture, respectively. As regards the latter aspect, electro-optical sensors represent the best option as their use is compatible with mass and power limitation of micro and small satellites, and their measurements can be processed to estimate all the pose parameters. Overall, the degree of complexity of the challenges related to pose determination largely varies depending on the nature of the targets, which may be actively/passively cooperative, uncooperative but known, or uncooperative and unknown space objects. In this respect, while cooperative pose determination has been successfully demonstrated in orbit, the uncooperative case is still under study by universities, research centers, space agencies and private companies. However, in both the cases, the demand for space applications involving relative navigation maneuvers, also in close-proximity, for which pose determination capabilities are mandatory, is significantly increasing. In this framework, a review of state-of-the-art techniques and algorithms developed in the last decades for cooperative and uncooperative pose determination by processing data provided by electro-optical sensors is herein presented. Specifically, their main advantages and drawbacks in terms of achieved performance, computational complexity, and sensitivity to variability of pose and target geometry, are highlighted.
Predictive Models and Computational Toxicology
Understanding the potential health risks posed by environmental chemicals is a significant challenge elevated by the large number of diverse chemicals with generally uncharacterized exposures, mechanisms, and toxicities. The ToxCast computational toxicology research program was l...
NASA Astrophysics Data System (ADS)
Slynko, Inna; Da Silva, Franck; Bret, Guillaume; Rognan, Didier
2016-09-01
High affinity ligands for a given target tend to share key molecular interactions with important anchoring amino acids and therefore often present quite conserved interaction patterns. This simple concept was formalized in a topological knowledge-based scoring function (GRIM) for selecting the most appropriate docking poses from previously X-rayed interaction patterns. GRIM first converts protein-ligand atomic coordinates (docking poses) into a simple 3D graph describing the corresponding interaction pattern. In a second step, proposed graphs are compared to that found from template structures in the Protein Data Bank. Last, all docking poses are rescored according to an empirical score (GRIMscore) accounting for overlap of maximum common subgraphs. Taking the opportunity of the public D3R Grand Challenge 2015, GRIM was used to rescore docking poses for 36 ligands (6 HSP90α inhibitors, 30 MAP4K4 inhibitors) prior to the release of the corresponding protein-ligand X-ray structures. When applied to the HSP90α dataset, for which many protein-ligand X-ray structures are already available, GRIM provided very high quality solutions (mean rmsd = 1.06 Å, n = 6) as top-ranked poses, and significantly outperformed a state-of-the-art scoring function. In the case of MAP4K4 inhibitors, for which preexisting 3D knowledge is scarce and chemical diversity is much larger, the accuracy of GRIM poses decays (mean rmsd = 3.18 Å, n = 30) although GRIM still outperforms an energy-based scoring function. GRIM rescoring appears to be quite robust with comparison to the other approaches competing for the same challenge (42 submissions for the HSP90 dataset, 27 for the MAP4K4 dataset) as it ranked 3rd and 2nd respectively, for the two investigated datasets. The rescoring method is quite simple to implement, independent on a docking engine, and applicable to any target for which at least one holo X-ray structure is available.
Strategies to Improve Learning of All Students in a Class
ERIC Educational Resources Information Center
Suraishkumar, G. K.
2018-01-01
The statistical distribution of the student learning abilities in a typical undergraduate engineering class poses a significant challenge to simultaneously improve the learning of all the students in the class. With traditional instruction styles, the students with significantly high learning abilities are not satisfied due to a feeling of…
Diplomatic Solutions to Additive Challenges
Additive manufacturing (AM) technology, colloquially known as 3D printing , will bring significant benefits to society, but also poses great risks...regimes, are not sufficient to address the challenges presented by 3D printing technology. The DOS should evaluate and promote unconventional strategies...from printed weapons proliferation. Working with other nations to resolve the appropriate balance between development and security, and to promote norms
ERIC Educational Resources Information Center
Mazzocco, Michele M. M.; Myers, Gwen F.; Lewis, Katherine E.; Hanich, Laurie B.; Murphy, Melissa M.
2013-01-01
Fractions pose significant challenges for many children, but for some children those challenges persist into high school. Here we administered a fractions magnitude comparison test to 122 children, from Grades 4 to 8, to test whether their knowledge of fractions typically learned early in the sequence of formal math instruction (e.g., fractions…
Fang, Hua; Zhang, Zhaoyang; Wang, Chanpaul Jin; Daneshmand, Mahmoud; Wang, Chonggang; Wang, Honggang
2015-01-01
Big data create values for business and research, but pose significant challenges in terms of networking, storage, management, analytics and ethics. Multidisciplinary collaborations from engineers, computer scientists, statisticians and social scientists are needed to tackle, discover and understand big data. This survey presents an overview of big data initiatives, technologies and research in industries and academia, and discusses challenges and potential solutions. PMID:26504265
Complete identification and eventual prevention of urban/suburban water quality problems pose significant monitoring challenges. Uncontrolled growth of impervious surfaces (roads, buildings and parking) causes detrimental hydrologic changes, stream channel erosion, habitat degra...
TRANSPORT OF TRICHLOROETHYLENE (TCE) IN NATURAL SOIL BY ELECTROOSMOSIS
Contamination in low permeability soils poses a significant technical challenge to in-situ remediation, primarily due to low mobilization of the contaminants and difficulty in uniform delivery of treatment reagents. An alternative approach using electroosmosis (EO) is used to mob...
Activity profiles of 309 ToxCast™ chemicals evaluated across 292 biochemical targets
Understanding the potential health risks posed by environmental chemicals is a significant challenge elevated by the large number of diverse chemicals with generally uncharacterized exposures, mechanisms, and toxicities. The present study is a performance evaluation and critical ...
Complete identification and eventual prevention of urban water quality problems pose significant monitoring, "smart growth" and water quality management challenges. Uncontrolled increase of impervious surface area (roads, buildings, and parking lots) causes detrimental hydrologi...
Hepatitis B Virus Infection in Tanzania: Current Status and Challenges
Bakshi, Fatma A.; Jaka, Hyasinta
2018-01-01
Hepatitis B is one of the most common infectious diseases in the world with high prevalence in most of sub-Saharan Africa countries. The complexity in its diagnosis and treatment poses a significant management challenge in the resource-limited settings including Tanzania, where most of the tests and drugs are either unavailable or unaffordable. This mini review aims at demonstrating the current status of the disease in the country and discussing the concomitant challenges in diagnosis, treatment, and prevention. PMID:29666656
Binding pose and affinity prediction in the 2016 D3R Grand Challenge 2 using the Wilma-SIE method
NASA Astrophysics Data System (ADS)
Hogues, Hervé; Sulea, Traian; Gaudreault, Francis; Corbeil, Christopher R.; Purisima, Enrico O.
2018-01-01
The Farnesoid X receptor (FXR) exhibits significant backbone movement in response to the binding of various ligands and can be a challenge for pose prediction algorithms. As part of the D3R Grand Challenge 2, we tested Wilma-SIE, a rigid-protein docking method, on a set of 36 FXR ligands for which the crystal structures had originally been blinded. These ligands covered several classes of compounds. To overcome the rigid protein limitations of the method, we used an ensemble of publicly available structures for FXR from the PDB. The use of the ensemble allowed Wilma-SIE to predict poses with average and median RMSDs of 2.3 and 1.4 Å, respectively. It was quite clear, however, that had we used a single structure for the receptor the success rate would have been much lower. The most successful predictions were obtained on chemical classes for which one or more crystal structures of the receptor bound to a molecule of the same class was available. In the absence of a crystal structure for the class, observing a consensus binding mode for the ligands of the class using one or more receptor structures of other classes seemed to be indicative of a reasonable pose prediction. Affinity prediction proved to be more challenging with generally poor correlation with experimental IC50s (Kendall tau 0.3). Even when the 36 crystal structures were used the accuracy of the predicted affinities was not appreciably improved. A possible cause of difficulty is the internal energy strain arising from conformational differences in the receptor across complexes, which may need to be properly estimated and incorporated into the SIE scoring function.
USDA-ARS?s Scientific Manuscript database
Lignocellulosic biomass conversion inhibitors furfural and HMF inhibit microbial growth and interfere with subsequent fermentation of ethanol, posing significant challenges for a sustainable cellulosic ethanol conversion industry. Numerous yeast genes were found to be associated with the inhibitor ...
NASA Technical Reports Server (NTRS)
LaRocco, Mark T.; Pierson, Duane L.
1999-01-01
In contemplating space travel beyond earth orbits, we humans face significant barriers and major challenges. Although researchers involved in several scientific subdisciplines, including space medicine and space life sciences, may provide insights to help overcome those barriers, their efforts are at an early stage of development, leaving open many questions of potentially major consequence.
Slynko, Inna; Da Silva, Franck; Bret, Guillaume; Rognan, Didier
2016-09-01
High affinity ligands for a given target tend to share key molecular interactions with important anchoring amino acids and therefore often present quite conserved interaction patterns. This simple concept was formalized in a topological knowledge-based scoring function (GRIM) for selecting the most appropriate docking poses from previously X-rayed interaction patterns. GRIM first converts protein-ligand atomic coordinates (docking poses) into a simple 3D graph describing the corresponding interaction pattern. In a second step, proposed graphs are compared to that found from template structures in the Protein Data Bank. Last, all docking poses are rescored according to an empirical score (GRIMscore) accounting for overlap of maximum common subgraphs. Taking the opportunity of the public D3R Grand Challenge 2015, GRIM was used to rescore docking poses for 36 ligands (6 HSP90α inhibitors, 30 MAP4K4 inhibitors) prior to the release of the corresponding protein-ligand X-ray structures. When applied to the HSP90α dataset, for which many protein-ligand X-ray structures are already available, GRIM provided very high quality solutions (mean rmsd = 1.06 Å, n = 6) as top-ranked poses, and significantly outperformed a state-of-the-art scoring function. In the case of MAP4K4 inhibitors, for which preexisting 3D knowledge is scarce and chemical diversity is much larger, the accuracy of GRIM poses decays (mean rmsd = 3.18 Å, n = 30) although GRIM still outperforms an energy-based scoring function. GRIM rescoring appears to be quite robust with comparison to the other approaches competing for the same challenge (42 submissions for the HSP90 dataset, 27 for the MAP4K4 dataset) as it ranked 3rd and 2nd respectively, for the two investigated datasets. The rescoring method is quite simple to implement, independent on a docking engine, and applicable to any target for which at least one holo X-ray structure is available.
Treatment of Bipolar Disorder in the University Student Population
ERIC Educational Resources Information Center
Federman, Russ
2011-01-01
University counseling centers are faced with the challenge of effectively treating bipolar students while also utilizing brief treatment frameworks and managing high patient volumes. Potential destabilization, particularly within the elevated mood phase, poses significant behavioral management issues for university clinicians and administrators,…
UNDERSTANDING THE FATE OF PETROLEUM HYDROCARBONS IN THE SUBSURFACE ENVIRONMENT
Sinca a significant number of the two or more million underground storage tank (UST) systems used for petroleum products leak, their cleanup poses a major environmental challenge. Our understnading of the fate of petroleum hydrocarbons in the subsurface environment is critical t...
Understanding potential health risks posed by environmental chemicals is a significant challenge elevated by large numbers of diverse chemicals with generally uncharacterized exposures, mechanisms and toxicities. The present study is a performance evaluation and critical analysis...
Challenges in Infective Endocarditis.
Cahill, Thomas J; Baddour, Larry M; Habib, Gilbert; Hoen, Bruno; Salaun, Erwan; Pettersson, Gosta B; Schäfers, Hans Joachim; Prendergast, Bernard D
2017-01-24
Infective endocarditis is defined by a focus of infection within the heart and is a feared disease across the field of cardiology. It is frequently acquired in the health care setting, and more than one-half of cases now occur in patients without known heart disease. Despite optimal care, mortality approaches 30% at 1 year. The challenges posed by infective endocarditis are significant. It is heterogeneous in etiology, clinical manifestations, and course. Staphylococcus aureus, which has become the predominant causative organism in the developed world, leads to an aggressive form of the disease, often in vulnerable or elderly patient populations. There is a lack of research infrastructure and funding, with few randomized controlled trials to guide practice. Longstanding controversies such as the timing of surgery or the role of antibiotic prophylaxis have not been resolved. The present article reviews the challenges posed by infective endocarditis and outlines current and future strategies to limit its impact. Copyright © 2017 American College of Cardiology Foundation. Published by Elsevier Inc. All rights reserved.
ERIC Educational Resources Information Center
Parres, Laura
2017-01-01
English language learners (ELLs) are a significant and growing subset of the school age population across the United States. The projected growth of ELL students is significant and poses unique challenges for school districts when assessing bilingual students for special education. The state of California has the most ELL students in the nation…
ERIC Educational Resources Information Center
Espinoza Gonzalez, Ricardo Andres
2017-01-01
Higher education has changed dramatically in the last 40 years. What was the privilege of rich nations or poor countries' elites is now an integral part of international competition and development strategies. However, the rapid expansion in enrollment has posed significant challenges in terms of providing adequate financing, access and securing…
USDA-ARS?s Scientific Manuscript database
Numerous toxic chemical compounds liberated from lignocellulosic biomass pretreatment inhibit subsequent microbial fermentation that pose a significant challenge to a sustainable and renewable bio-based fermentation industry. Toxin removal procedures by physical or chemical means are essentially imp...
Marasas' et al. (1984) “Toxigenic Fusarium species: Identity and mycotoxicology” revisited
USDA-ARS?s Scientific Manuscript database
Fusarium ranks as one of the world's most economically destructive and taxonomically challenging genera of mycotoxigenic plant pathogens. Due to the significant threat that fusarial toxins pose to agricultural biosecurity, food safety, and plant and animal health, several compendia have attempted to...
Meta-Assessment in a Project-Based Systems Engineering Course
ERIC Educational Resources Information Center
Wengrowicz, Niva; Dori, Yehudit Judy; Dori, Dov
2017-01-01
Project-based learning (PBL) facilitates significant learning, but it poses a major assessment challenge for assessing individual content knowledge. We developed and implemented an assessment approach and tool for a mandatory undergraduate systems engineering PBL-based course. We call this type of assessment "student-oriented"…
Teaching Determinants Using Rook Arrangements
ERIC Educational Resources Information Center
Hendrickson, Anders O. F.
2018-01-01
Teaching determinants poses significant challenges to the instructor of a proof-based undergraduate linear algebra course. The standard definition by cofactor expansion is ugly, lacks symmetry, and is hard for students to use in proofs. We introduce a visual definition of the determinant that interprets permutations as arrangements of…
Attracting Preservice Teachers to Remote Locations
ERIC Educational Resources Information Center
Young, Kenneth D.; Grainger, Peter; James, Dennis
2018-01-01
Teaching in rural/remote regions poses many challenges to teachers and is identified as a priority research area by the state government. Despite initiatives by the Queensland state government and university providers to solve the issue through various incentives designed to attract teachers, the problem remains significant. This research…
Understanding the potential health risks posed by environmental chemicals is a significant challenge driven by the large number of diverse chemicals with generally uncharacterized exposures, mechanisms and toxicities. The U.S. EPA’s ToxCast chemical prioritization research projec...
Security Planning and Policies to Meet the Challenges of Climate Change
2010-07-01
Security Climate change poses challenges to societies and governments that go far beyond the alteration of our environment. The physical impacts of...capacity of governments to respond. In this sense, the growing likelihood of events such as mass migrations, crop failures, economic shocks, public...riots and violence, floods and other natural disasters, widespread epidemics, and competition for resources pose serious challenges for governments and
Prospective evaluation of shape similarity based pose prediction method in D3R Grand Challenge 2015
NASA Astrophysics Data System (ADS)
Kumar, Ashutosh; Zhang, Kam Y. J.
2016-09-01
Evaluation of ligand three-dimensional (3D) shape similarity is one of the commonly used approaches to identify ligands similar to one or more known active compounds from a library of small molecules. Apart from using ligand shape similarity as a virtual screening tool, its role in pose prediction and pose scoring has also been reported. We have recently developed a method that utilizes ligand 3D shape similarity with known crystallographic ligands to predict binding poses of query ligands. Here, we report the prospective evaluation of our pose prediction method through the participation in drug design data resource (D3R) Grand Challenge 2015. Our pose prediction method was used to predict binding poses of heat shock protein 90 (HSP90) and mitogen activated protein kinase kinase kinase kinase (MAP4K4) ligands and it was able to predict the pose within 2 Å root mean square deviation (RMSD) either as the top pose or among the best of five poses in a majority of cases. Specifically for HSP90 protein, a median RMSD of 0.73 and 0.68 Å was obtained for the top and the best of five predictions respectively. For MAP4K4 target, although the median RMSD for our top prediction was only 2.87 Å but the median RMSD of 1.67 Å for the best of five predictions was well within the limit for successful prediction. Furthermore, the performance of our pose prediction method for HSP90 and MAP4K4 ligands was always among the top five groups. Particularly, for MAP4K4 protein our pose prediction method was ranked number one both in terms of mean and median RMSD when the best of five predictions were considered. Overall, our D3R Grand Challenge 2015 results demonstrated that ligand 3D shape similarity with the crystal ligand is sufficient to predict binding poses of new ligands with acceptable accuracy.
USDA-ARS?s Scientific Manuscript database
The contrast between the point-scale nature of current ground-based soil moisture instrumentation and the footprint resolution (typically >100 square kilometers) of satellites used to retrieve soil moisture poses a significant challenge for the validation of data products from satellite missions suc...
On Higher Education in China and Canada from the Perspective of Humanity-Orientation
ERIC Educational Resources Information Center
Liang, Xiao; Han, Xuefen
2013-01-01
With the rapid development of the social economy, the ideologies, ways of thinking, psychological qualities, and values of contemporary university students have changed significantly. This poses new challenges for traditional teaching administration. Importance has been attached to the humanity issue in university teaching, which attracts wide…
Translating in vitro data and biological information into a predictive model for human toxicity poses a significant challenge. This is especially true for complex adaptive systems such as the embryo where cellular dynamics are precisely orchestrated in space and time. Computer ce...
Taking Stock: Existing Resources for Assessing a New Vision of Science Learning
ERIC Educational Resources Information Center
Alonzo, Alicia C.; Ke, Li
2016-01-01
A new vision of science learning described in the "Next Generation Science Standards"--particularly the science and engineering practices and their integration with content--pose significant challenges for large-scale assessment. This article explores what might be learned from advances in large-scale science assessment and…
Rap and Orality in a Post-NCLB/ALEC World
ERIC Educational Resources Information Center
Paul, Dierdre Glenn
2013-01-01
Rigid foci on accountability, accreditation, and customer service pose significant challenges for literacy educators today. The most consequential identified as the snuffing out of scholastic innovation and erosion of academic freedom. This article recounts a recent experience that occurred while the author prepared a lesson for an undergraduate…
Uncovering Discovery Layer Services
ERIC Educational Resources Information Center
Kennedy, Sean P.
2014-01-01
Today's electronic information landscape is growing exponentially with no signs of slowing. This poses a significant challenge for academic libraries. Librarians must continually learn and adapt to harness this explosion of resources. To fulfill their claim as the leaders in the information field they must be effective in providing access and…
USDA-ARS?s Scientific Manuscript database
Monitoring of rangelands poses significant challenges to land managers due to broad extent and many uses of rangelands. The Bureau of Land Management’s (BLM) Assessment, Inventory, and Monitoring (AIM) program seeks to efficiently collect standard, quantitative monitoring data which is collected onc...
Strengthening Rural Schools: Training Paraprofessionals in Crisis Prevention and Intervention.
ERIC Educational Resources Information Center
Allen, Melissa; Ashbaker, Betty Y.; Stott, Kathryn A.
The long-term effects of crisis and tragedy can be improved significantly by immediate intervention and emergency mental health services. Providing crisis intervention in rural schools poses challenges related to lack of financial resources, community resources, and trained personnel; isolation of rural schools; and long distances between school…
Management of contaminated sediments poses significant challenges due to varied contaminants and volumes of sediments to
manage. Dredging, capping, and monitored natural recovery (MNR) are the primary approaches for managing the contaminated sediment risks.
Understanding ho...
Management of contaminated sediments poses significant challenges due to varied contaminants and volumes of sediments to manage. Dredging, capping, and monitored natural recovery (MNR) are the primary approaches for managing the contaminated sediment risks. Understanding how eff...
A Research Analytics Framework-Supported Recommendation Approach for Supervisor Selection
ERIC Educational Resources Information Center
Zhang, Mingyu; Ma, Jian; Liu, Zhiying; Sun, Jianshan; Silva, Thushari
2016-01-01
Identifying a suitable supervisor for a new research student is vitally important for his or her academic career. Current information overload and information disorientation have posed significant challenges for new students. Existing research for supervisor identification focuses on quality assessment of candidates, but ignores indirect relevance…
This is a webinar page for the Sustainable Management of Materials (SMM) Web Academy webinar titled, An Introduction to Lithium Batteries and the Challenges that they Pose to the Waste and Recycling Industry.
Career Counseling and the Information Highway: Heeding the Road Signs.
ERIC Educational Resources Information Center
O'Halloran, Theresa M.; Fahr, Alicia V.; Keller, Jenny R.
2002-01-01
Traveling the "information highway" in the process of career counseling or providing career counseling services via the Internet pose additional challenges for counselors. The authors use current ethical guidelines to guide discussion of, and possible resolutions to, challenges posed by incorporating the Internet into career counseling. (Contains…
ERIC Educational Resources Information Center
Joy, Javed A.; Julius, Rose J.; Akter, Rashida; Baron, David A.
2010-01-01
Purpose: Every year increasing numbers of candidates request special accommodations for high-stakes medical licensing examinations, due to ADHD, on the basis of the Americans with Disabilities Act (ADA). This poses significant challenges for both the applicant and the medical boards and has significant financial, legal, and ethical implications.…
Michelle C. Kondo; Danya Keene; Bernadette C. Hohl; John M. MacDonald; Charles C. Branas
2015-01-01
Vacant and abandoned buildings pose significant challenges to the health and safety of communities. In 2011 the City of Philadelphia began enforcing a Doors and Windows Ordinance that required property owners of abandoned buildings to install working doors and windows in all structural openings or face significant fines. We tested the effects of the new ordinance on...
Bed Bug Epidemic: A Challenge to Public Health
ERIC Educational Resources Information Center
Ratnapradipa, Dhitinut; Ritzel, Dale O.; Haramis, Linn D.; Bliss, Kadi R.
2011-01-01
In recent years, reported cases of bed bug infestations in the U.S. and throughout the world have escalated dramatically, posing a global public health problem. Although bed bugs are not known to transmit disease to humans, they pose both direct and indirect public health challenges in terms of health effects, treatment, cost, and resource…
Henriques, C; Garnett, K; Weatherhead, E K; Lickorish, F A; Forrow, D; Delgado, J
2015-04-15
Society gets numerous benefits from the water environment. It is crucial to ensure that water management practices deliver these benefits over the long-term in a sustainable and cost-effective way. Currently, hydromorphological alterations and nutrient enrichment pose the greatest challenges in European water bodies. The rapidly changing climatic and socio-economic boundary conditions pose further challenges to water management decisions and the achievement of policy goals. Scenarios are a strategic tool useful in conducting systematic investigations of future uncertainties pertaining to water management. In this study, the use of scenarios revealed water management challenges for England and Wales to 2050. A set of existing scenarios relevant to river basin management were elaborated through stakeholder workshops and interviews, relying on expert knowledge to identify drivers of change, their interdependencies, and influence on system dynamics. In a set of four plausible alternative futures, the causal chain from driving forces through pressures to states, impacts and responses (DPSIR framework) was explored. The findings suggest that scenarios driven by short-term economic growth and competitiveness undermine current environmental legislative requirements and exacerbate the negative impacts of climate change, producing a general deterioration of water quality and physical habitats, as well as reduced water availability with adverse implications for the environment, society and economy. Conversely, there are substantial environmental improvements under the scenarios characterised by long-term sustainability, though achieving currently desired environmental outcomes still poses challenges. The impacts vary across contrasting generic catchment types that exhibit distinct future water management challenges. The findings suggest the need to address hydromorphological alterations, nutrient enrichment and nitrates in drinking water, which are all likely to be exacerbated in the future. Future-proofing river basin management measures that deal with these challenges is crucial moving forward. The use of scenarios to future-proof strategy, policy and delivery mechanisms is discussed to inform next steps. Copyright © 2014 Elsevier B.V. All rights reserved.
Soft-rigid interaction mechanism towards a lobster-inspired hybrid actuator
NASA Astrophysics Data System (ADS)
Chen, Yaohui; Wan, Fang; Wu, Tong; Song, Chaoyang
2018-01-01
Soft pneumatic actuators (SPAs) are intrinsically light-weight, compliant and therefore ideal to directly interact with humans and be implemented into wearable robotic devices. However, they also pose new challenges in describing and sensing their continuous deformation. In this paper, we propose a hybrid actuator design with bio-inspirations from the lobsters, which can generate reconfigurable bending movements through the internal soft chamber interacting with the external rigid shells. This design with joint and link structures enables us to exactly track its bending configurations that previously posed a significant challenge to soft robots. Analytic models are developed to illustrate the soft-rigid interaction mechanism with experimental validation. A robotic glove using hybrid actuators to assist grasping is assembled to illustrate their potentials in safe human-robot interactions. Considering all the design merits, our work presents a practical approach to the design of next-generation robots capable of achieving both good accuracy and compliance.
Neutron Imaging Control Report: FY 2016
DOE Office of Scientific and Technical Information (OSTI.GOV)
Gibson, D. J.
2016-11-30
During the 2016 fiscal year, work began on the supervision and control systems for the neutron source currently under construction in the B194 accelerator caves. This source relies on a deuteron beam colliding with a high-speed stream of deuterium gas to create neutrons, which poses significant technical challenges. To help overcome those challenges, an integrated, operator-focused control architecture is required to collect and assimilate disparate data from a variety of measurement points, as well as provide the means to remotely control the system hardware.
Teacher Education to Meet the Challenges Posed by Child Sexual Abuse
ERIC Educational Resources Information Center
Mathews, Ben
2011-01-01
The phenomenon of child sexual abuse has significant implications for teachers' pre-service training and professional development. Teachers have a pedagogical role in dealing with abused children, and a legal and professional duty to report suspected child sexual abuse. Teachers require support and training to develop the specialised knowledge and…
A Faculty-Based Mentorship Circle: Positioning New Faculty for Success
ERIC Educational Resources Information Center
Waddell, Janice; Martin, Jennifer; Schwind, Jasna K.; Lapum, Jennifer L.
2016-01-01
Multiple and competing priorities within a dynamic and changing academic environment can pose significant challenges for new faculty. Mentorship has been identified as an important strategy to help socialize new faculty to their roles and the expectations of the academic environment. It also helps them learn new skills that will position them to…
An NMR Experiment Based on Off-the-Shelf Digital Data-Acquisition Equipment
ERIC Educational Resources Information Center
Hilty, Christian; Bowen, Sean
2010-01-01
Nuclear magnetic resonance (NMR) poses significant challenges for teaching in the context of an undergraduate laboratory, foremost because of high equipment cost. Current off-the-shelf data-acquisition hardware, however, is sufficiently powerful to constitute the core of a fully digital NMR spectrometer operating at the earth's field. We present…
Vocabulary Learning on the Internet: Using a Structured Think-Aloud Procedure
ERIC Educational Resources Information Center
Ebner, Rachel J.; Ehri, Linnea C.
2013-01-01
Using the Internet as a learning tool has great promise, but also poses significant challenges. Theories and research confirm the importance of students' engagement in self-regulated learning processes for effective Internet learning. In this article the Authors describe a structured think-aloud procedure intended to support students'…
ERIC Educational Resources Information Center
Maguire, Sue; Huddleston, Prue
2009-01-01
The current policy intention, that all young people remain in some form of accredited education or training to the age of 18 by 2015, poses significant challenges. The jobs without training (JWT) group includes young people who are in full-time work and not in receipt of training leading to National Vocational Qualification level 2 (or above);…
ERIC Educational Resources Information Center
Bogdaniak, Roman C.
Dually diagnosed adolescents suffering from both severe emotional disturbance and substance abuse/addiction constitute a special population which poses a challenge to health professionals in special education as well as clinical settings. The prevalence of substance use, abuse, and addiction has been shown to be significantly above the national…
Weather Worlding: Learning with the Elements in Early Childhood
ERIC Educational Resources Information Center
Rooney, Tonya
2018-01-01
In the context of challenges posed by climate change, this paper draws attention to the significance of children's relationship with weather. The paper contends that it is time to engage more closely with children's weather relations when developing and experimenting with new environmental pedagogies. Furthermore, it is argued that there is a need…
A Framework for the Governance of Information Security
ERIC Educational Resources Information Center
Edwards, Charles K.
2013-01-01
Information security is a complex issue, which is very critical for success of modern businesses. It can be implemented with the help of well-tested global standards and best practices. However, it has been studied that the human aspects of information security compliance pose significant challenge to its practitioners. There has been significant…
The database design and diverse application of NLCD 2001 pose significant challenges for accuracy assessment because numerous objectives are of interest, including accuracy of land cover, percent urban imperviousness, percent tree canopy, land-cover composition, and net change. ...
Domestic Violence and Poverty: Some Women's Experiences
ERIC Educational Resources Information Center
Slabbert, Ilze
2017-01-01
Purpose: Domestic violence poses a major challenge to social workers. Low-income families are significantly more likely to have to contend with domestic violence, as poverty can act as a fuelling factor in this type of conflict. The objective of this study was to explore and describe the experiences of low-income abused women. Method: A…
Building Systems for Evaluation of Teachers Poses Challenge
ERIC Educational Resources Information Center
Sawchuk, Stephen
2011-01-01
Rounding the corner on the design of new teacher-evaluation plans, states and districts are beginning to wrestle with the significant technical and logistical hurdles for transforming their blueprints into reality. In the coming months, more states--especially those that won grants through the $4 billion federal Race to the Top initiative--are…
ERIC Educational Resources Information Center
Duggan, James R.
2014-01-01
The article engages with the opportunities and constraints raised by embedded research during times of rapid and extensive organisational change. Embedded research is an increasingly common approach for funding PhD studentships. The rapid and extensive reforms of the English public sector pose significant and underexplored challenges for embedded…
A fragment-based approach to the SAMPL3 Challenge
NASA Astrophysics Data System (ADS)
Kulp, John L.; Blumenthal, Seth N.; Wang, Qiang; Bryan, Richard L.; Guarnieri, Frank
2012-05-01
The success of molecular fragment-based design depends critically on the ability to make predictions of binding poses and of affinity ranking for compounds assembled by linking fragments. The SAMPL3 Challenge provides a unique opportunity to evaluate the performance of a state-of-the-art fragment-based design methodology with respect to these requirements. In this article, we present results derived from linking fragments to predict affinity and pose in the SAMPL3 Challenge. The goal is to demonstrate how incorporating different aspects of modeling protein-ligand interactions impact the accuracy of the predictions, including protein dielectric models, charged versus neutral ligands, ΔΔGs solvation energies, and induced conformational stress. The core method is based on annealing of chemical potential in a Grand Canonical Monte Carlo (GC/MC) simulation. By imposing an initially very high chemical potential and then automatically running a sequence of simulations at successively decreasing chemical potentials, the GC/MC simulation efficiently discovers statistical distributions of bound fragment locations and orientations not found reliably without the annealing. This method accounts for configurational entropy, the role of bound water molecules, and results in a prediction of all the locations on the protein that have any affinity for the fragment. Disregarding any of these factors in affinity-rank prediction leads to significantly worse correlation with experimentally-determined free energies of binding. We relate three important conclusions from this challenge as applied to GC/MC: (1) modeling neutral ligands—regardless of the charged state in the active site—produced better affinity ranking than using charged ligands, although, in both cases, the poses were almost exactly overlaid; (2) simulating explicit water molecules in the GC/MC gave better affinity and pose predictions; and (3) applying a ΔΔGs solvation correction further improved the ranking of the neutral ligands. Using the GC/MC method under a variety of parameters in the blinded SAMPL3 Challenge provided important insights to the relevant parameters and boundaries in predicting binding affinities using simulated annealing of chemical potential calculations.
Lessons about Climate Change Pose Many Challenges for Science Teachers
ERIC Educational Resources Information Center
Cavanagh, Sean
2007-01-01
This article reports on lessons about climate change which pose many challenges for science teachers. The natural world today offers a broad--and dire--catalog of scientific phenomena for teachers wanting to craft classroom lessons on the topic of climate change. As public concern about global warming increases, teachers are carving out a larger…
NASA Astrophysics Data System (ADS)
da Silva Figueiredo Celestino Gomes, Priscila; Da Silva, Franck; Bret, Guillaume; Rognan, Didier
2018-01-01
A novel docking challenge has been set by the Drug Design Data Resource (D3R) in order to predict the pose and affinity ranking of a set of Farnesoid X receptor (FXR) agonists, prior to the public release of their bound X-ray structures and potencies. In a first phase, 36 agonists were docked to 26 Protein Data Bank (PDB) structures of the FXR receptor, and next rescored using the in-house developed GRIM method. GRIM aligns protein-ligand interaction patterns of docked poses to those of available PDB templates for the target protein, and rescore poses by a graph matching method. In agreement with results obtained during the previous 2015 docking challenge, we clearly show that GRIM rescoring improves the overall quality of top-ranked poses by prioritizing interaction patterns already visited in the PDB. Importantly, this challenge enables us to refine the applicability domain of the method by better defining the conditions of its success. We notably show that rescoring apolar ligands in hydrophobic pockets leads to frequent GRIM failures. In the second phase, 102 FXR agonists were ranked by decreasing affinity according to the Gibbs free energy of the corresponding GRIM-selected poses, computed by the HYDE scoring function. Interestingly, this fast and simple rescoring scheme provided the third most accurate ranking method among 57 contributions. Although the obtained ranking is still unsuitable for hit to lead optimization, the GRIM-HYDE scoring scheme is accurate and fast enough to post-process virtual screening data.
The ACO paradox impacting physicians.
Bansal, Gunjan; West, Daniel J
2012-01-01
Accountable care organizations (ACOs) would hold care providers jointly accountable for the quality and costs of care, allow consumers the freedom to choose their providers, and involve physicians and consumers in their shared decision-making. Even though the ACO model proposes physician empowerment, it also poses significant financial and change-management challenges for physicians. Furthermore, the "patient-centered" ACOs that have been established to safeguard consumer sovereignty pose the risks of concentrating healthcare markets further and exacerbating the existing disparities in healthcare. We conducted a survey study to understand physicians' perspectives of ACOs by seeking their first-hand feedback. The survey results suggest that there are significant communication gaps between physicians and healthcare administrators; and efficient communication can help improve physician-administrator alignment and help them identify opportunities that would be critical to the success of ACOs.
Optimizing care for the obese patient in interventional radiology
Aberle, Dwight; Charles, Hearns; Hodak, Steven; O’Neill, Daniel; Oklu, Rahmi; Deipolyi, Amy R.
2017-01-01
With the rising epidemic of obesity, interventional radiologists are treating increasing numbers of obese patients, as comorbidities associated with obesity preclude more invasive treatments. These patients are at heightened risk of vascular and oncologic disease, both of which often require interventional radiology care. Obese patients pose unique challenges in imaging, technical feasibility, and periprocedural monitoring. This review describes the technical and clinical challenges posed by this population, with proposed methods to mitigate these challenges and optimize care. PMID:28082253
ERIC Educational Resources Information Center
Gustafson, Joey; Keller, Eric; LaVallee, Robert E.; Stewart, Nichole H.
2010-01-01
A basic premise of charter school reform in public education is offering more autonomy in the use of funds and the design of curriculum in exchange for greater accountability in academic and financial outcomes. This premise poses a significant policy challenge for state policymakers to establish an appropriate level of regulation; charter schools…
Evaluation of seven drought tolerant tree species for central California
E.G. McPherson; S. Albers
2014-01-01
Climate change poses challenges for the Southwest, where an already parched region is expected to get hotter and, in its southern half, significantly drier (Garfin et al. 2013). Increased heat and sustained drought will stress water sources and redefine urban landscapes. As landscapes gradually evolve from lush to xeric, tolerance of trees to water-related stress...
Microbiome Data Science: Understanding Our Microbial Planet.
Kyrpides, Nikos C; Eloe-Fadrosh, Emiley A; Ivanova, Natalia N
2016-06-01
Microbiology is experiencing a revolution brought on by recent developments in sequencing technology. The unprecedented volume of microbiome data being generated poses significant challenges that are currently hindering progress in the field. Here, we outline the major bottlenecks and propose a vision to advance microbiome research as a data-driven science. Copyright © 2016 Elsevier Ltd. All rights reserved.
Joseph P. Flood; Leo H. McAvoy
2000-01-01
Wilderness campsites heavily damaged by recreational use pose a significant management challenge that threatens the integrity of the wilderness resource and the quality of the visitorsâ experience. This study, conducted in the Mission Mountains Wilderness of northwestern Montana, surveyed 293 visitors to determine what influence heavily damaged campsites and site...
Young Sexual Citizens: Reimagining Sex Education as an Essential Form of Civic Engagement
ERIC Educational Resources Information Center
Illes, Judit
2012-01-01
Sexually transmitted infections (STIs) pose a significant threat to the health and well-being of populations worldwide, and to young people in particular. Despite empirical evidence that comprehensive sex education is an important tool for prevention, the legitimacy and content of sex education in schools continue to be challenged by conservative…
ERIC Educational Resources Information Center
Spencer, Sarah; Clegg, Judy; Stackhouse, Joy
2010-01-01
Assessing adolescent language skills poses significant challenges due to the subtle nature of language proficiency at this age, along with the high linguistic demands both academically and socially. As with young children, the current range of language assessments designed specifically for adolescents mostly includes standardized tests. This…
Meeting Our Shared Aspirations: Supporting Economically and Socially Relevant Higher Education
ERIC Educational Resources Information Center
Smith, Steve
2010-01-01
This article represents a lecture given by Professor Steve Smith at the Association of University Administrators Annual Lecture on 20 October 2009. There has been considerable change in the sector since the lecture was delivered, however, the Editor and author felt that the issues still pose significant challenges to higher education (HE), and…
USDA-ARS?s Scientific Manuscript database
Like many agricultural crops, the cultivated cotton genome is large and polyploid (~2.5Gb), consisting of two very similar repeat-rich subgenomes, whose size and complexity pose significant challenges for accurate genome reconstruction using whole-genome shotgun approaches. A strategy for accurately...
The Lexico-Syntactic Marking of Chronological Order: Insights from Vietnamese Learners of ESL.
ERIC Educational Resources Information Center
Tickoo, Asha
1998-01-01
This study of the use of "then"/"after that" by Vietnamese English-as-a-Second-Language learners suggests that the temporal adverbial poses a significant learning challenge similar to morphological means of temporal reference. Learner usage is monitored by a looser notion of salience, which emerges from the transference of a salience-marking…
ERIC Educational Resources Information Center
Koch, Steven; Borg, Terry
2011-01-01
An Illinois district brings a local university into the district to craft advanced learning embedded in the needs of specific schools. Community High School District 155 in Crystal Lake, Ill., and Northern Illinois University (NIU) College of Education engaged in a partnership that has provided significant benefits, posed limited challenges, and…
Andrew Fall; B. Sturtevant; M.-J. Fortin; M. Papaik; F. Doyon; D. Morgan; K. Berninger; C. Messier
2010-01-01
The complexity and multi-scaled nature of forests poses significant challenges to understanding and management. Models can provide useful insights into process and their interactions, and implications of alternative management options. Most models, particularly scientific models, focus on a relatively small set of processes and are designed to operate within a...
User Interface Preferences in the Design of a Camera-Based Navigation and Wayfinding Aid
ERIC Educational Resources Information Center
Arditi, Aries; Tian, YingLi
2013-01-01
Introduction: Development of a sensing device that can provide a sufficient perceptual substrate for persons with visual impairments to orient themselves and travel confidently has been a persistent rehabilitation technology goal, with the user interface posing a significant challenge. In the study presented here, we enlist the advice and ideas of…
Conduct Problems in Young, School-Going Children in Ireland: Prevalence and Teacher Response
ERIC Educational Resources Information Center
Hyland, Lynda; Ní Mháille, Grainne; Lodge, Anne; McGilloway, Sinead
2014-01-01
Conduct problems in school settings can pose significant challenges for both children and teachers. This study examined the teacher-reported prevalence of conduct problems in a sample of young children (N?=?445) in the first two years of formal education. A secondary aim was to assess teachers' perceptions of child behaviour and their classroom…
Children of Immigrants in Trento: Educational Achievement through the Lens of Friendship
ERIC Educational Resources Information Center
Mantovani, Debora; Martini, Elisa
2008-01-01
During the past three decades, Italy has changed from a country of emigration to one of immigration. This has produced significant changes in the country's social, cultural and economic structures and poses major new challenges to the education system. An important indicator of the changing situation is the increasing number of immigrant children…
Learning Disabilities and Career Development. Practice Application Brief No. 20.
ERIC Educational Resources Information Center
Kerka, Sandra
The lifelong process of career development poses special challenges for people with learning disabilities (LD). Literature on employment issues for adults with LD frames on-the-job problems in terms of individual deficits or recasts the issues as a function of the significant societal barriers faced by those who do not fit the norm. Research on…
Non-native plants and adaptive collaborative approaches to ecosystem restoration [Chapter 8
John Schelhas; James H. Miller; Jeanne C. Chambers
2012-01-01
Non-native invasive plant species (NNIPS) pose a serious socio-ecological challenge due to their potential to replace and damage critical human-sustaining ecosystems (OTA 1993; Mack et al. 2000; Pimentel 2002). The impacts of non-native species are widespread and significant - altering ecosystem structure and function, threatening other species, and imposing human...
ERIC Educational Resources Information Center
Pouliot, Danielle M.; Müller, Eve; Frasché, Nancy F.; Kern, Ann S.; Resti, Israelle H.
2017-01-01
Speech and language impairments can pose significant challenges to the successful workplace inclusion of young adults with intellectual disabilities (IDs) and/or autism spectrum disorders (ASD). Breakdowns are most likely to occur when support staff, workplace supervisors, or co-workers are unsure how to support effective communication.…
Two case studies of highly insoluble plutonium inhalation with implications for bioassay.
Carbaugh, E H; La Bone, T R
2003-01-01
Two well characterised Pu inhalation cases show some remarkable similarities between substantially different types of Pu oxide. The circumstances of exposure, therapy, bioassay data, chemical solubility studies and dosimetry associated with these cases suggest that highly insoluble Pu may be more common than previously thought, and can pose significant challenges to bioassay programmes.
Two Case Studies of Highly Insoluble Plutonium Inhalation with Implications for Bioassay
DOE Office of Scientific and Technical Information (OSTI.GOV)
Carbaugh, Eugene H.; La Bone, Thomas R.
2003-01-01
Two well-characterized Pu inhalation cases show some remarkable similarities between substantially different types of Pu oxide. The circumstances of exposure, therapy, bioassay data, chemical solubility studies, and dosimetry associated with these cases suggests taht highly insoluble Pu may be more common than previously thought, and can pose significant challenges to bioassay programs.
ERIC Educational Resources Information Center
Kapatsinski, Vsevolod; Olejarczuk, Paul; Redford, Melissa A.
2017-01-01
We report on rapid perceptual learning of intonation contour categories in adults and 9- to 11-year-old children. Intonation contours are temporally extended patterns, whose perception requires temporal integration and therefore poses significant working memory challenges. Both children and adults form relatively abstract representations of…
The Role of Social Foundations in Preparing Teachers for Culturally Relevant Practice
ERIC Educational Resources Information Center
Ryan, Ann Marie
2006-01-01
Addressing the issue of teachers' low expectations of students of color and those in poverty poses significant challenges to teacher education. The growing body of research focused on this issue documents ways teachers can make a real difference in the educational lives of children. Ladson-Billings' (1992; 1994; 1995) and others demonstrate that…
Foundational literature for moving native plant materials in changing climates
Mary I. Williams; Kas Dumroese; Jeremy Pinto; Martin F. Jurgensen
2015-01-01
Seed transfer guidelines and zones are used to manage the movement of plant materials, but by the end of the century many landscapes across the globe will have climates that are incompatible with current vegetation. The mismatch in rates between climate change and plant migration and adaptation will pose significant challenges for natural resource managers, especially...
Deinstitutionalization: Its Impact on Community Mental Health Centers and the Seriously Mentally Ill
ERIC Educational Resources Information Center
Kliewer, Stephen P.; McNally Melissa; Trippany, Robyn L.
2009-01-01
Deinstitutionalization has had a significant impact on the mental health system, including the client, the agency, and the counselor. For clients with serious mental illness, learning to live in a community setting poses challenges that are often difficult to overcome. Community mental health agencies must respond to these specific needs, thus…
ERIC Educational Resources Information Center
Silloway, Torey
2010-01-01
Most nonprofit leaders understand the importance of building strong organizational capacity, but finding ways to support and strengthen this capacity often poses significant challenges. Nonprofit leaders may hesitate to divert money from direct services when funds are needed to support operations. Some experts in the field also note what they…
ERIC Educational Resources Information Center
Wong, Lung-Hsiang; Chai, Ching Sing; Zhang, Xujuan; King, Ronnel B.
2015-01-01
Integrating technologies into teaching and learning poses a significant challenge for many teachers who lack socio-techno-pedagogical know-how and time to design interventions. A possible solution is to design sound technology-enhanced learning (TEL) environments with relevant content and pedagogical tools to reduce teachers' design efforts.…
Changing the Face of the Academy: Innovative Approaches to Faculty Recruitment
ERIC Educational Resources Information Center
Brown, Ara C.; Greenwood, James J.
2010-01-01
With the ever-changing landscape of America, diversity, equity, and social justice issues continue to be of great importance in independent schools. Undeniably, diversity work holds benefits--which is why it has a place in so many mission statements--but it also poses significant challenges. In particular, the recruitment and retention of faculty…
The Universities of Russia: Areas and Prospects of Development
ERIC Educational Resources Information Center
Berdashkevich, A. P.
2011-01-01
The last two decades have seen a significant increase in university students in Russia, the growth of private and state-financed higher education, and the beginnings of a move to a national network of research institutions. The recent economic recession, however, poses a challenge to the continuance of current fee-based higher education in Russia.…
Jeremy Fried; Paul Meznarich
2014-01-01
Large wildfires in the United States pose significant challenges to fire management agencies charged with protecting lives, property, and natural resources. A vigorous initial response to a wildfire, a process referred to as "initial attack," can greatly reduce the likelihood of the fire becoming larger and causing substantial damage. Successful...
Significant Figures in Measurements with Uncertainty: A Working Criterion
NASA Astrophysics Data System (ADS)
Vilchis, Abraham
2017-03-01
Generally speaking, students have difficulty reporting out measurements and estimates of quantities used in the laboratory, and with handling the significant figures associated with them. When required to make calculation involving quantities with different numbers of significant figures, they have difficulty in assigning the corresponding digits to the final result. When in addition, the quantities have uncertainty, the operations entailed pose an even greater challenge. The article advocates for some working rules for students (and teachers) in an effort to combat this problem.
D3R grand challenge 2015: Evaluation of protein-ligand pose and affinity predictions
NASA Astrophysics Data System (ADS)
Gathiaka, Symon; Liu, Shuai; Chiu, Michael; Yang, Huanwang; Stuckey, Jeanne A.; Kang, You Na; Delproposto, Jim; Kubish, Ginger; Dunbar, James B.; Carlson, Heather A.; Burley, Stephen K.; Walters, W. Patrick; Amaro, Rommie E.; Feher, Victoria A.; Gilson, Michael K.
2016-09-01
The Drug Design Data Resource (D3R) ran Grand Challenge 2015 between September 2015 and February 2016. Two targets served as the framework to test community docking and scoring methods: (1) HSP90, donated by AbbVie and the Community Structure Activity Resource (CSAR), and (2) MAP4K4, donated by Genentech. The challenges for both target datasets were conducted in two stages, with the first stage testing pose predictions and the capacity to rank compounds by affinity with minimal structural data; and the second stage testing methods for ranking compounds with knowledge of at least a subset of the ligand-protein poses. An additional sub-challenge provided small groups of chemically similar HSP90 compounds amenable to alchemical calculations of relative binding free energy. Unlike previous blinded Challenges, we did not provide cognate receptors or receptors prepared with hydrogens and likewise did not require a specified crystal structure to be used for pose or affinity prediction in Stage 1. Given the freedom to select from over 200 crystal structures of HSP90 in the PDB, participants employed workflows that tested not only core docking and scoring technologies, but also methods for addressing water-mediated ligand-protein interactions, binding pocket flexibility, and the optimal selection of protein structures for use in docking calculations. Nearly 40 participating groups submitted over 350 prediction sets for Grand Challenge 2015. This overview describes the datasets and the organization of the challenge components, summarizes the results across all submitted predictions, and considers broad conclusions that may be drawn from this collaborative community endeavor.
D3R Grand Challenge 2015: Evaluation of Protein-Ligand Pose and Affinity Predictions
Gathiaka, Symon; Liu, Shuai; Chiu, Michael; Yang, Huanwang; Stuckey, Jeanne A; Kang, You Na; Delproposto, Jim; Kubish, Ginger; Dunbar, James B.; Carlson, Heather A.; Burley, Stephen K.; Walters, W. Patrick; Amaro, Rommie E.; Feher, Victoria A.; Gilson, Michael K.
2017-01-01
The Drug Design Data Resource (D3R) ran Grand Challenge 2015 between September 2015 and February 2016. Two targets served as the framework to test community docking and scoring methods: (i) HSP90, donated by AbbVie and the Community Structure Activity Resource (CSAR), and (ii) MAP4K4, donated by Genentech. The challenges for both target datasets were conducted in two stages, with the first stage testing pose predictions and the capacity to rank compounds by affinity with minimal structural data; and the second stage testing methods for ranking compounds with knowledge of at least a subset of the ligand-protein poses. An additional sub-challenge provided small groups of chemically similar HSP90 compounds amenable to alchemical calculations of relative binding free energy. Unlike previous blinded Challenges, we did not provide cognate receptors or receptors prepared with hydrogens and likewise did not require a specified crystal structure to be used for pose or affinity prediction in Stage 1. Given the freedom to select from over 200 crystal structures of HSP90 in the PDB, participants employed workflows that tested not only core docking and scoring technologies, but also methods for addressing water-mediated ligand-protein interactions, binding pocket flexibility, and the optimal selection of protein structures for use in docking calculations. Nearly 40 participating groups submitted over 350 prediction sets for Grand Challenge 2015. This overview describes the datasets and the organization of the challenge components, summarizes the results across all submitted predictions, and considers broad conclusions that may be drawn from this collaborative community endeavor. PMID:27696240
Pose-Invariant Face Recognition via RGB-D Images.
Sang, Gaoli; Li, Jing; Zhao, Qijun
2016-01-01
Three-dimensional (3D) face models can intrinsically handle large pose face recognition problem. In this paper, we propose a novel pose-invariant face recognition method via RGB-D images. By employing depth, our method is able to handle self-occlusion and deformation, both of which are challenging problems in two-dimensional (2D) face recognition. Texture images in the gallery can be rendered to the same view as the probe via depth. Meanwhile, depth is also used for similarity measure via frontalization and symmetric filling. Finally, both texture and depth contribute to the final identity estimation. Experiments on Bosphorus, CurtinFaces, Eurecom, and Kiwi databases demonstrate that the additional depth information has improved the performance of face recognition with large pose variations and under even more challenging conditions.
Vision Based SLAM in Dynamic Scenes
2012-12-20
the correct relative poses between cameras at frame F. For this purpose, we detect and match SURF features between cameras in dilierent groups, and...all cameras in s uch a challenging case. For a compa rison, we disabled the ’ inte r-camera pose estimation’ and applied the ’ intra-camera pose esti
Fast normal mode computations of capsid dynamics inspired by resonance
NASA Astrophysics Data System (ADS)
Na, Hyuntae; Song, Guang
2018-07-01
Increasingly more and larger structural complexes are being determined experimentally. The sizes of these systems pose a formidable computational challenge to the study of their vibrational dynamics by normal mode analysis. To overcome this challenge, this work presents a novel resonance-inspired approach. Tests on large shell structures of protein capsids demonstrate that there is a strong resonance between the vibrations of a whole capsid and those of individual capsomeres. We then show how this resonance can be taken advantage of to significantly speed up normal mode computations.
Neurological Disease in Lupus: Toward a Personalized Medicine Approach.
McGlasson, Sarah; Wiseman, Stewart; Wardlaw, Joanna; Dhaun, Neeraj; Hunt, David P J
2018-01-01
The brain and nervous system are important targets for immune-mediated damage in systemic lupus erythematosus (SLE), resulting in a complex spectrum of neurological syndromes. Defining nervous system disease in lupus poses significant challenges. Among the difficulties to be addressed are a diversity of clinical manifestations and a lack of understanding of their mechanistic basis. However, despite these challenges, progress has been made in the identification of pathways which contribute to neurological disease in SLE. Understanding the molecular pathogenesis of neurological disease in lupus will inform both classification and approaches to clinical trials.
Multi-object segmentation using coupled nonparametric shape and relative pose priors
NASA Astrophysics Data System (ADS)
Uzunbas, Mustafa Gökhan; Soldea, Octavian; Çetin, Müjdat; Ünal, Gözde; Erçil, Aytül; Unay, Devrim; Ekin, Ahmet; Firat, Zeynep
2009-02-01
We present a new method for multi-object segmentation in a maximum a posteriori estimation framework. Our method is motivated by the observation that neighboring or coupling objects in images generate configurations and co-dependencies which could potentially aid in segmentation if properly exploited. Our approach employs coupled shape and inter-shape pose priors that are computed using training images in a nonparametric multi-variate kernel density estimation framework. The coupled shape prior is obtained by estimating the joint shape distribution of multiple objects and the inter-shape pose priors are modeled via standard moments. Based on such statistical models, we formulate an optimization problem for segmentation, which we solve by an algorithm based on active contours. Our technique provides significant improvements in the segmentation of weakly contrasted objects in a number of applications. In particular for medical image analysis, we use our method to extract brain Basal Ganglia structures, which are members of a complex multi-object system posing a challenging segmentation problem. We also apply our technique to the problem of handwritten character segmentation. Finally, we use our method to segment cars in urban scenes.
ERIC Educational Resources Information Center
O'Brien, Maeve
2005-01-01
This paper investigates the phenomenon of mothers' emotional labour in relation to children's transfer from first- to second-level schooling: a time that has been shown to pose significant challenges for students and their families. It seeks to break the silence that surrounds the recognition and production of emotional labour in general, and…
Restoration of a fractured central incisor.
Olson, Bradley J
2012-03-01
The treatment of a traumatically damaged single central incisor poses significant challenges relative to function and esthetics to the restoring clinician. Providing a good long-term prognosis is paramount when determining whether to maintain or extract a structurally compromised tooth. Successful restoration demands timely and thorough risk assessment along with excellent communication with both the patient and the laboratory fabricating the restoration.
Small enterprises as important hardwood lumber consumers: Evidence from the current housing downturn
Urs Buehlmann; Matthew Bumgardner; Al Schuler; Jeff Crissey
2011-01-01
Housing fixtures (such as cabinets, flooring, moldings, and stairways) have become a major market for secondary wood products manufacturers in the United States and a major user of U.S. hardwood lumber. Thus, downturns in housing markets, with associated declines in the demand and price for fixtures, can pose significant challenges to the profitability of these...
ERIC Educational Resources Information Center
Shan, Hongxia; Guo, Shibao
2013-01-01
The last few decades have witnessed both an expansion and a transformation of immigration flows, which pose significant challenges with respect to how people work with differences across culture and space. Against this background, this paper explores how some Chinese immigrant engineers respond to differences in the Canadian labour market. It not…
NASA Technical Reports Server (NTRS)
Kurian, R.; Grifin, A.
2002-01-01
Developing production-quality software to process the large volumes of scientific data is the responsibility of the TES Ground Data System, which is being developed at the Jet Propulsion Laboratory together with support contractor Raytheon/ITSS. The large data volume and processing requirements of the TES pose significant challenges to the design.
Martin, Graeme; Beech, Nic; MacIntosh, Robert; Bushfield, Stacey
2015-01-01
The discourse of leaderism in health care has been a subject of much academic and practical debate. Recently, distributed leadership (DL) has been adopted as a key strand of policy in the UK National Health Service (NHS). However, there is some confusion over the meaning of DL and uncertainty over its application to clinical and non-clinical staff. This article examines the potential for DL in the NHS by drawing on qualitative data from three co-located health-care organisations that embraced DL as part of their organisational strategy. Recent theorising positions DL as a hybrid model combining focused and dispersed leadership; however, our data raise important challenges for policymakers and senior managers who are implementing such a leadership policy. We show that there are three distinct forms of disconnect and that these pose a significant problem for DL. However, we argue that instead of these disconnects posing a significant problem for the discourse of leaderism, they enable a fantasy of leadership that draws on and supports the discourse. © 2014 The Authors. Sociology of Health & Illness © 2014 Foundation for the Sociology of Health & Illness/John Wiley & Sons Ltd.
Cobo, Nicole H; Sankar, Raman; Murata, Kristina K; Sewak, Sarika L; Kezele, Michele A; Matsumoto, Joyce H
2015-02-01
Refractory status epilepticus carries significant morbidity and mortality. Recent reports have promoted the use of the ketogenic diet as an effective treatment for refractory status epilepticus. We describe our recent experience with instituting the ketogenic diet for 4 critically ill children in refractory status epilepticus, ranging in age from 9 weeks to 13.5 years after failure of traditional treatment. The ketogenic diet allowed these patients to be weaned off continuous infusions of anesthetics without recurrence of status epilepticus, though delayed ketosis and persistently elevated glucose measurements posed special challenges to effective initiation, and none experienced complete seizure cessation. The ease of sustaining myocardial function with fatty acid energy substrates compares favorably over the myocardial toxicity posed by anesthetic doses of barbiturates and contributes to the safety profile of the ketogenic diet. The ketogenic diet can be implemented successfully and safely for the treatment of refractory status epilepticus in pediatric patients. © The Author(s) 2014.
Teachers Implementing Mathematical Problem Posing in the Classroom: Challenges and Strategies
ERIC Educational Resources Information Center
Leung, Shuk-kwan S.
2013-01-01
This paper reports a study about how a teacher educator shared knowledge with teachers when they worked together to implement mathematical problem posing (MPP) in the classroom. It includes feasible methods for getting practitioners to use research-based tasks aligned to the curriculum in order to encourage children to pose mathematical problems.…
DOCKSCORE: a webserver for ranking protein-protein docked poses.
Malhotra, Sony; Mathew, Oommen K; Sowdhamini, Ramanathan
2015-04-24
Proteins interact with a variety of other molecules such as nucleic acids, small molecules and other proteins inside the cell. Structure-determination of protein-protein complexes is challenging due to several reasons such as the large molecular weights of these macromolecular complexes, their dynamic nature, difficulty in purification and sample preparation. Computational docking permits an early understanding of the feasibility and mode of protein-protein interactions. However, docking algorithms propose a number of solutions and it is a challenging task to select the native or near native pose(s) from this pool. DockScore is an objective scoring scheme that can be used to rank protein-protein docked poses. It considers several interface parameters, namely, surface area, evolutionary conservation, hydrophobicity, short contacts and spatial clustering at the interface for scoring. We have implemented DockScore in form of a webserver for its use by the scientific community. DockScore webserver can be employed, subsequent to docking, to perform scoring of the docked solutions, starting from multiple poses as inputs. The results, on scores and ranks for all the poses, can be downloaded as a csv file and graphical view of the interface of best ranking poses is possible. The webserver for DockScore is made freely available for the scientific community at: http://caps.ncbs.res.in/dockscore/ .
Photonic integrated circuits: new challenges for lithography
NASA Astrophysics Data System (ADS)
Bolten, Jens; Wahlbrink, Thorsten; Prinzen, Andreas; Porschatis, Caroline; Lerch, Holger; Giesecke, Anna Lena
2016-10-01
In this work routes towards the fabrication of photonic integrated circuits (PICs) and the challenges their fabrication poses on lithography, such as large differences in feature dimension of adjacent device features, non-Manhattan-type features, high aspect ratios and significant topographic steps as well as tight lithographic requirements with respect to critical dimension control, line edge roughness and other key figures of merit not only for very small but also for relatively large features, are highlighted. Several ways those challenges are faced in today's low-volume fabrication of PICs, including the concept multi project wafer runs and mix and match approaches, are presented and possible paths towards a real market uptake of PICs are discussed.
Wang, ShuQi; Lifson, Mark A.; Inci, Fatih; Liang, Li-Guo; Sheng, Ye-Feng; Demirci, Utkan
2016-01-01
The striking prevalence of HIV, TB and malaria, as well as outbreaks of emerging infectious diseases, such as influenza A (H7N9), Ebola and MERS, poses great challenges for patient care in resource-limited settings (RLS). However, advanced diagnostic technologies cannot be implemented in RLS largely due to economic constraints. Simple and inexpensive point-of-care (POC) diagnostics, which rely less on environmental context and operator training, have thus been extensively studied to achieve early diagnosis and treatment monitoring in non-laboratory settings. Despite great input from material science, biomedical engineering and nanotechnology for developing POC diagnostics, significant technical challenges are yet to be overcome. Summarized here are the technical challenges associated with POC diagnostics from a RLS perspective and the latest advances in addressing these challenges are reviewed. PMID:26777725
ERIC Educational Resources Information Center
Brown, Tom H.
2015-01-01
Barber, Donnelly & Rizvi (2013): "An avalanche is coming: Higher education and the revolution ahead" addresses some significant issues in higher education and poses some challenging questions to open and distance learning (ODL) administrators, policy makers, and of course to ODL faculty in general. Barber et al.'s paper does not…
Taking Up the Security Challenge of Climate Change
2009-08-01
depletion, anthropogenic pollution , and pandemic disease, among other phenomena, all of which pose significant environmental security risks in their...AUTHOR RYMN J. PARSONS is Assistant Counsel to and Environmental Practice Team Leader for Naval Facilities Engineering Command, Mid- Atlantic , located at...Naval Station, Norfolk, VA. Also a Navy Reservist, with the rank of captain, he is Staff Judge Advocate to Commander, Navy Region Mid- Atlantic
Surrogate endpoints and competing risk of death in cardiac arrest research.
McCredie, Victoria A; Scales, Damon C
2016-06-29
We urgently need new therapies to improve outcomes after cardiac arrest. Initial studies typically target surrogate endpoints, and these studies help to inform subsequent larger trials that are powered to measure more patient-orientated clinical outcomes such as survival. The competing risk of death and premature assessment of neurological prognosis pose significant challenges to measuring these surrogate endpoints after cardiac arrest.
Significance of cannabis use to dental practice.
Maloney, William James
2011-04-01
The illicit use of the three main forms of cannabis-marijuana, hash, hash oil-pose certain obstacles and challenges to the dental professional. There are a number of systemic, as well as oral/head and neck manifestations, associated with cannabis use. Dentists need to be aware of these manifestations in order to take whatever precautions and/or modifications to the proposed treatment that might be necessary.
ERIC Educational Resources Information Center
Brokaw, James J.; Byram, Jessica N.; Traser, Courtney J.; Arbor, Tafline C.
2016-01-01
Anatomy faculties are integral to basic science instruction in medical schools, particularly given the preponderance of anatomic instruction in the preclinical curriculum. Recent years have witnessed major curricular restructuring and other emerging national trends that pose significant challenges to anatomists. An examination of anatomy faculty…
The social aspects of landscape change: protecting open space under the pressure of development
Paul H. Gobster; Susan I. Stewart; David N. Bengston
2004-01-01
The extent of developed land in many parts of the world has increased rapidly in recent decades, posing significant challenges to the protection of forests, agricultural lands, and other natural and culturally modified green areas in urban and rural settings. Sustaining these open spaces has long been seen as a critical issue economically, and it is now increasingly...
Electro-textile garments for power and data distribution
NASA Astrophysics Data System (ADS)
Slade, Jeremiah R.; Winterhalter, Carole
2015-05-01
U.S. troops are increasingly being equipped with various electronic assets including flexible displays, computers, and communications systems. While these systems can significantly enhance operational capabilities, forming reliable connections between them poses a number of challenges in terms of comfort, weight, ergonomics, and operational security. IST has addressed these challenges by developing the technologies needed to integrate large-scale cross-seam electrical functionality into virtually any textile product, including the various garments and vests that comprise the warfighter's ensemble. Using this technology IST is able to develop textile products that do not simply support or accommodate a network but are the network.
Quantifying VOC emissions from polymers: A case study
DOE Office of Scientific and Technical Information (OSTI.GOV)
Schulze, J.K.; Qasem, J.S.; Snoddy, R.
1996-12-31
Evaluating residual volatile organic compound emissions emanating from low-density polyethylene can pose significant challenges. These challenges include quantifying emissions from: (a) multiple process lines with different operating conditions; (b) several different comonomers; (c) variations of comonomer content in each grade; and (d) over 120 grades of LDPE. This presentation is a Case Study outlining a project to develop grade-specific emission data for low-density polyethylene pellets. This study included extensive laboratory analyses and required the development of a relational database to compile analytical results, calculate the mean concentration and standard deviation, and generate emissions reports.
McGirr, Alexander; Davis, Lindsay; Vila-Rodriguez, Fidel
2014-04-30
Somatic symptom disorders are common causes of disability and suffering, and can pose significant management challenges. Idiopathic burning mouth syndrome is a challenging somatic symptom disorder with relatively high prevalence, particularly among post-menopausal women. Here, we present the case of a woman with severe treatment refractory idiopathic burning mouth syndrome and comorbid major depressive disorder, who was successfully treated with bitemporal electroconvulsive therapy. This case highlights the potential effectiveness of electroconvulsive therapy in idiopathic burning mouth syndrome when other treatment options have been exhausted. Copyright © 2014 Elsevier Ireland Ltd. All rights reserved.
Neurological Disease in Lupus: Toward a Personalized Medicine Approach
McGlasson, Sarah; Wiseman, Stewart; Wardlaw, Joanna; Dhaun, Neeraj; Hunt, David P. J.
2018-01-01
The brain and nervous system are important targets for immune-mediated damage in systemic lupus erythematosus (SLE), resulting in a complex spectrum of neurological syndromes. Defining nervous system disease in lupus poses significant challenges. Among the difficulties to be addressed are a diversity of clinical manifestations and a lack of understanding of their mechanistic basis. However, despite these challenges, progress has been made in the identification of pathways which contribute to neurological disease in SLE. Understanding the molecular pathogenesis of neurological disease in lupus will inform both classification and approaches to clinical trials. PMID:29928273
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.
NASA Astrophysics Data System (ADS)
Prathipati, Philip; Nagao, Chioko; Ahmad, Shandar; Mizuguchi, Kenji
2016-09-01
The D3R 2015 grand drug design challenge provided a set of blinded challenges for evaluating the applicability of our protocols for pose and affinity prediction. In the present study, we report the application of two different strategies for the two D3R protein targets HSP90 and MAP4K4. HSP90 is a well-studied target system with numerous co-crystal structures and SAR data. Furthermore the D3R HSP90 test compounds showed high structural similarity to existing HSP90 inhibitors in BindingDB. Thus, we adopted an integrated docking and scoring approach involving a combination of both pharmacophoric and heavy atom similarity alignments, local minimization and quantitative structure activity relationships modeling, resulting in the reasonable prediction of pose [with the root mean square deviation (RMSD) values of 1.75 Å for mean pose 1, 1.417 Å for the mean best pose and 1.85 Å for the mean all poses] and affinity (ROC AUC = 0.702 at 7.5 pIC50 cut-off and R = 0.45 for 180 compounds). The second protein, MAP4K4, represents a novel system with limited SAR and co-crystal structure data and little structural similarity of the D3R MAP4K4 test compounds to known MAP4K4 ligands. For this system, we implemented an exhaustive pose and affinity prediction protocol involving docking and scoring using the PLANTS software which considers side chain flexibility together with protein-ligand fingerprints analysis assisting in pose prioritization. This protocol through fares poorly in pose prediction (with the RMSD values of 4.346 Å for mean pose 1, 4.69 Å for mean best pose and 4.75 Å for mean all poses) and produced reasonable affinity prediction (AUC = 0.728 at 7.5 pIC50 cut-off and R = 0.67 for 18 compounds, ranked 1st among 80 submissions).
2009-12-01
Research, Ottawa , 1998 as issued jointly by the Canadian Institutes of Health Research, the Natural Sciences and Engineering Research Council of Canada...Flight Rules ) skills. Nine Bell 412CF helicopters were produced from existing CH-146 Griffons, which posed technical challenges. One such compromise was...IFR (Instrument Flight Rules ) skills. Nine Bell 412CF helicopters were produced from existing CH-146 Griffons, which posed technical challenges. One
Terrain, weather pose challenges in Minnesota project
DOE Office of Scientific and Technical Information (OSTI.GOV)
Trojack, L.
1994-12-01
This paper briefly reviews an innovative method used in installing a natural gas pipeline in Minnesota which traversed a marsh area. Because of the special problems associated with this wetland area, special equipment and techniques had to be used to minimize disturbance associated with the construction. It describes the equipment and the resulting performance the equipment had. It proved to significantly reduce disturbance and result in minimum site restoration work.
Effect of climate change and resource scarcity on health care.
Richardson, Janet; Grose, Jane; Jackson, Bethany; Gill, Jamie-Lee; Sadeghian, Hannah Becky; Hertel, Johannes; Kelsey, Janet
2014-07-15
Climate change and resource scarcity pose significant threats to healthcare delivery. Nurses should develop the skills to cope with these challenges in the future. Skills sessions using sustainability scenarios can help nursing students to understand the effect climate change and resource scarcity will have on health care. Involving design students in clinical skills sessions can encourage multidisciplinary working and help to find solutions to promote healthcare sustainability.
The challenge of treating conduct disorder in low-resourced settings: rap music to the rescue.
Evans, Dylan J
2010-12-01
Conduct disorder is one of the most frequent serious childhood problems that present for treatment in community clinic settings. Evidence-based treatments for conduct disorder are intensive and require considerable resources to implement. In low-resourced contexts it is often not feasible to implement evidence-based treatments in their current form, which poses significant challenges for clinicians attempting to treat children in these settings. This article explores these challenges using a case study of the treatment of a young adolescent boy with a short-term multisystem intervention where rap music was employed as a powerful tool to facilitate an empathic connection in therapy and as a projective technique to explore underlying emotional difficulties.
Global Climate Change and the Mitigation Challenge
Book edited by Frank Princiotta titled Global Climate Change--The Technology Challenge Transparent modeling tools and the most recent literature are used, to quantify the challenge posed by climate change and potential technological remedies. The chapter examines forces driving ...
Bumblebees minimize control challenges by combining active and passive modes in unsteady winds
NASA Astrophysics Data System (ADS)
Ravi, Sridhar; Kolomenskiy, Dmitry; Engels, Thomas; Schneider, Kai; Wang, Chun; Sesterhenn, Jörn; Liu, Hao
2016-10-01
The natural wind environment that volant insects encounter is unsteady and highly complex, posing significant flight-control and stability challenges. It is critical to understand the strategies insects employ to safely navigate in natural environments. We combined experiments on free flying bumblebees with high-fidelity numerical simulations and lower-order modeling to identify the mechanics that mediate insect flight in unsteady winds. We trained bumblebees to fly upwind towards an artificial flower in a wind tunnel under steady wind and in a von Kármán street formed in the wake of a cylinder. Analysis revealed that at lower frequencies in both steady and unsteady winds the bees mediated lateral movement with body roll - typical casting motion. Numerical simulations of a bumblebee in similar conditions permitted the separation of the passive and active components of the flight trajectories. Consequently, we derived simple mathematical models that describe these two motion components. Comparison between the free-flying live and modeled bees revealed a novel mechanism that enables bees to passively ride out high-frequency perturbations while performing active maneuvers at lower frequencies. The capacity of maintaining stability by combining passive and active modes at different timescales provides a viable means for animals and machines to tackle the challenges posed by complex airflows.
NASA Astrophysics Data System (ADS)
Réau, Manon; Langenfeld, Florent; Zagury, Jean-François; Montes, Matthieu
2018-01-01
The Drug Design Data Resource (D3R) Grand Challenges are blind contests organized to assess the state-of-the-art methods accuracy in predicting binding modes and relative binding free energies of experimentally validated ligands for a given target. The second stage of the D3R Grand Challenge 2 (GC2) was focused on ranking 102 compounds according to their predicted affinity for Farnesoid X Receptor. In this task, our workflow was ranked 5th out of the 77 submissions in the structure-based category. Our strategy consisted in (1) a combination of molecular docking using AutoDock 4.2 and manual edition of available structures for binding poses generation using SeeSAR, (2) the use of HYDE scoring for pose selection, and (3) a hierarchical ranking using HYDE and MM/GBSA. In this report, we detail our pose generation and ligands ranking protocols and provide guidelines to be used in a prospective computer aided drug design program.
Will learning to solve one-step equations pose a challenge to 8th grade students?
NASA Astrophysics Data System (ADS)
Ngu, Bing Hiong; Phan, Huy P.
2017-08-01
Assimilating multiple interactive elements simultaneously in working memory to allow understanding to occur, while solving an equation, would impose a high cognitive load. Element interactivity arises from the interaction between elements within and across operational and relational lines. Moreover, operating with special features (e.g. negative pronumeral) poses additional challenge to master equation solving skills. In an experiment, 41 8th grade students (girls = 16, boys = 25) sat for a pre-test, attended a session about equation solving, completed an acquisition phase which constituted the main intervention and were tested again in a post-test. The results showed that at post-test, students performed better on one-step equations tapping low rather than high element interactivity knowledge. In addition, students performed better on those one-step equations that contained no special features. Thus, both the degree of element interactivity and the operation with special features affect the challenge posed to 8th grade students on learning how to solve one-step equations.
NASA Astrophysics Data System (ADS)
Simpson, J. M.; Smail, Ian; Wang, Wei-Hao; Riechers, D.; Dunlop, J. S.; Ao, Y.; Bourne, N.; Bunker, A.; Chapman, S. C.; Chen, Chian-Chou; Dannerbauer, H.; Geach, J. E.; Goto, T.; Harrison, C. M.; Hwang, H. S.; Ivison, R. J.; Kodama, Tadayuki; Lee, C.-H.; Lee, H.-M.; Lee, M.; Lim, C.-F.; Michałowski, M. J.; Rosario, D. J.; Shim, H.; Shu, X. W.; Swinbank, A. M.; Tee, W.-L.; Toba, Y.; Valiante, E.; Wang, Junxian; Zheng, X. Z.
2017-07-01
The identification of high-redshift, massive galaxies with old stellar populations may pose challenges to some models of galaxy formation. However, to securely classify a galaxy as quiescent, it is necessary to exclude significant ongoing star formation, something that can be challenging to achieve at high redshifts. In this Letter, we analyze deep ALMA/870 μm and SCUBA-2/450 μm imaging of the claimed “post-starburst” galaxy ZF 20115 at z = 3.717 that exhibits a strong Balmer break and absorption lines. The rest-frame far-infrared imaging identifies a luminous starburst 0.″4 ± 0.″1 (˜3 kpc in projection) from the position of the ultraviolet/optical emission and is consistent with lying at the redshift of ZF 20115. The star-forming component, with an obscured star formation rate of {100}-70+15 {M}⊙ {{yr}}-1, is undetected in the rest-frame ultraviolet but contributes significantly to the lower angular resolution photometry at rest-frame wavelengths ≳3500 Å. This contribution from the obscured starburst, especially in the Spitzer/IRAC wavebands, significantly complicates the determination of a reliable stellar mass for the ZF 20015 system, and we conclude that this source does not pose a challenge to current models of galaxy formation. The multi-wavelength observations of ZF 20115 unveil a complex system with an intricate and spatially varying star formation history. ZF 20115 demonstrates that understanding high-redshift obscured starbursts will only be possible with multi-wavelength studies that include high-resolution observations, available with the James Webb Space Telescope, at mid-infrared wavelengths.
Saint-Pierre, Sylvain
2011-07-01
The climate change issue includes meeting the growing demand for electricity while reducing the impacts from energy sources. Applying carbon capture and storage technology to fossil fuel energy and increasing renewable energy pose greater challenges than increasing nuclear energy. International Energy Agency's (IEA) electricity demand of 30 000 TWh by 2030 can be met with 10 000 TWh each from renewable, nuclear and fossil fuel energy. However, the ill-imposed very strict control of tiny public exposure to ionising radiation from nuclear energy continues to pose a serious hindrance. Effort needs to be re-balanced to produce an even-handed control of public exposure with emphasis on the most significant sources (i.e. natural background radiation and medical use) and vice versa. The on-going revision of the International Atomic Energy Agency Basic Safety Standards (BSS) provides an opportunity to achieve this internationally so that national regulations can be subsequently remediated. There can be no urgency in a BSS revision that fails to encompass such perspective.
NASA Astrophysics Data System (ADS)
Bhakat, Soumendranath; Åberg, Emil; Söderhjelm, Pär
2018-01-01
Advanced molecular docking methods often aim at capturing the flexibility of the protein upon binding to the ligand. In this study, we investigate whether instead a simple rigid docking method can be applied, if combined with multiple target structures to model the backbone flexibility and molecular dynamics simulations to model the sidechain and ligand flexibility. The methods are tested for the binding of 35 ligands to FXR as part of the first stage of the Drug Design Data Resource (D3R) Grand Challenge 2 blind challenge. The results show that the multiple-target docking protocol performs surprisingly well, with correct poses found for 21 of the ligands. MD simulations started on the docked structures are remarkably stable, but show almost no tendency of refining the structure closer to the experimentally found binding pose. Reconnaissance metadynamics enhances the exploration of new binding poses, but additional collective variables involving the protein are needed to exploit the full potential of the method.
Bhakat, Soumendranath; Åberg, Emil; Söderhjelm, Pär
2018-01-01
Advanced molecular docking methods often aim at capturing the flexibility of the protein upon binding to the ligand. In this study, we investigate whether instead a simple rigid docking method can be applied, if combined with multiple target structures to model the backbone flexibility and molecular dynamics simulations to model the sidechain and ligand flexibility. The methods are tested for the binding of 35 ligands to FXR as part of the first stage of the Drug Design Data Resource (D3R) Grand Challenge 2 blind challenge. The results show that the multiple-target docking protocol performs surprisingly well, with correct poses found for 21 of the ligands. MD simulations started on the docked structures are remarkably stable, but show almost no tendency of refining the structure closer to the experimentally found binding pose. Reconnaissance metadynamics enhances the exploration of new binding poses, but additional collective variables involving the protein are needed to exploit the full potential of the method.
Halikiopoulou, Daphne
2018-01-01
Speed and Mannion make a good case that the rise of populism poses significant challenges for health policy. This commentary suggests that the link between populism and health policy should be further nuanced in four ways. First, a deconstruction of the term populism itself and a focus on the far right dimension of populist politics; second, a focus on the supply side and more specifically the question of nationalism and the ‘national preference’; third, the dynamics of party competition during economic crisis; and fourth the question of policy, and more specifically the extent to which certain labour market policies are able to mediate demand for the far right. PMID:29524946
The dumbest experiment in space. [problems in laboratory apparatus adaption to space environment
NASA Technical Reports Server (NTRS)
Prouty, C. R.
1981-01-01
A simple conceptual experiment is used to illustrate (1) the fundamentals of performing an experiment, including the theoretical concept, the experiment design, the performance of the experiment, and the recording of observations; (2) the increasing challenges posed by performance of the same experiment in a location remote from the experimenter, such as additional planning and equipment and their associated cost increases; and (3) the significant growth of difficulties to be overcome when the simple experiment is performed in a highly restrictive environment, such as a spacecraft in orbit, with someone else remotely operating the experiment. It is shown that performing an experiment in the remote, hostile environment of space will pose difficulties equaling or exceeding those of the experiment itself, entailing mastery of a widening range of disciplines.
Plant-based FRET biosensor discriminates enviornmental zinc levels
USDA-ARS?s Scientific Manuscript database
Heavy metal accumulation in the environment poses great risks to flora and fauna. However, monitoring sites prone to accumulation poses scale and economic challenges. In this study, we present and test a method for monitoring these sites using fluorescent resonance energy transfer (FRET) change in r...
Barrett, Damon
2010-03-01
This commentary addresses some of the challenges posed by the broader normative, legal and policy framework of the United Nations for the international drug control system. The 'purposes and principles' of the United Nations are presented and set against the threat based rhetoric of the drug control system and the negative consequences of that system. Some of the challenges posed by human rights law and norms to the international drug control system are also described, and the need for an impact assessment of the current system alongside alternative policy options is highlighted as a necessary consequence of these analyses. Copyright (c) 2010 Elsevier B.V. All rights reserved.
Software and the future of programming languages.
Aho, Alfred V
2004-02-27
Although software is the key enabler of the global information infrastructure, the amount and extent of software in use in the world today are not widely understood, nor are the programming languages and paradigms that have been used to create the software. The vast size of the embedded base of existing software and the increasing costs of software maintenance, poor security, and limited functionality are posing significant challenges for the software R&D community.
Strategic Impact of Cyber Warfare Rules for the United States
2010-03-01
Despite the growing complexities of cyberspace and the significant strategic challenge cyber warfare poses on the United States’ vital interests few...specific rules for cyber warfare exist. The United States should seek to develop and maintain cyber warfare rules in order to establish...exemplify the need for multilaterally prepared cyber warfare rules that will reduce the negative influence cyber warfare presently has on the United States’ national interests.
Developing a Viable Approach for Effective Tiered Systems
2007-01-17
TERMS 16. SECURITY CLASSIFICATION OF: a. REPORT 19a. NAME OF RESPONSIBLE PERSON 19b. TELEPHONE NUMBER (include area code ) b. ABSTRACT c. THIS PAGE 18...is changing the world. Now deal with it” (New Scientist 2006). If true, this significant message is one that would extend well beyond the realm of...system-of-systems poses formidable challenges for the acquisitions bureaucracy and the defense industries” (Dombrowski et al. 2002). “TRLs
Transient anosmia during acute phase electroconvulsive therapy: a report of 2 cases.
Upshaw, William N; Hubbard, Jacqueline D; Ali, Sadia; Fernandez, Jamie Winderbaum
2013-12-01
Treatment-resistant psychiatric illness poses a clinical challenge to psychiatrists in both inpatient and outpatient settings. Although electroconvulsive therapy is a relatively safe option for the treatment of these patients, initiation of this treatment requires a conscientious discussion of the risks and benefits of the procedure to obtain informed consent. The 2 cases presented here describe transient anosmia, a seldom reported but potentially significant adverse effect of electroconvulsive therapy.
Challenges in the Management of a Patient with Myxoedema Coma in Ghana: A Case Report.
Akpalu, Josephine; Atiase, Yacoba; Yorke, Ernest; Fiscian, Henrietta; Kootin-Sanwu, Cecilia; Akpalu, Albert
2017-03-01
Myxoedema coma is a rare life-threatening disease, and it is essential that it is managed appropriately to reduce the associated high mortality. However, in the setting where efficient healthcare delivery is hampered by inadequacies, the management of such cases may pose a significant challenge. We present the case of a middle-aged woman diagnosed with myxoedema coma and severe hyponatremia. The case report highlights some of the challenges that may be encountered during the management of myxoedema coma in similar settings and outlines the management strategies undertaken to overcome them in the absence of national guidelines. It also brings to the fore the need for clinicians to look out for clinical features suggestive of hypothyroidism particularly among high risk individuals for early diagnosis and treatment. None declared.
Professional conduct among registered nurses in the use of online social networking sites.
Levati, Sara
2014-10-01
To explore the use of Facebook by Registered Nurses (RNs) in Italy and the United Kingdom (UK), focusing on the disclosure of personal and professional information. The use of online social network sites among medical students and doctors is posing new ethical challenges to the profession. To date, little research has explored the use of online social networking sites among nurses. A cross-national survey. Data were assessed on 124 nurses' profile pages, readily available without viewing restrictions. Content analysis and inferential statistics were undertaken to describe usage and identify similarities and differences between the two country-groups of nurses. Data were collected between December 2011-January 2012. Overall, UK and Italian RNs showed a similar use of the online platform, tending to disclose personal pictures, home town and current home location, as well as updates and comments related to personal and work-related activities. A statistically significant higher proportion of nurses in Italy disclosed their sexual orientation. In both groups, a few cases were observed of potentially unprofessional content in relation to the use of alcohol, nudity and material of a salacious nature. Although most of the UK and Italy RNs appear to be aware of the risks posed by their online exposure, their online activity indicates the blurring of their personal and professional lives; this is posing new ethical, legal and professional challenges to members of the nursing profession. Further research and debate is encouraged at national and international level. © 2014 John Wiley & Sons Ltd.
Intercollegiate Athletics Today and Tomorrow: The President's Challenge
ERIC Educational Resources Information Center
Hanford, George H.
1977-01-01
Colleges and university presidents must come to terms with the challenges posed by intercollegiate athletics. The author offers concrete ideas and suggestions aimed at breaking through the confusion surrounding intercollegiate athletics. (Editor/LBH)
Progress and challenges associated with halal authentication of consumer packaged goods.
Premanandh, Jagadeesan; Bin Salem, Samara
2017-11-01
Abusive business practices are increasingly evident in consumer packaged goods. Although consumers have the right to protect themselves against such practices, rapid urbanization and industrialization result in greater distances between producers and consumers, raising serious concerns on the supply chain. The operational complexities surrounding halal authentication pose serious challenges on the integrity of consumer packaged goods. This article attempts to address the progress and challenges associated with halal authentication. Advancement and concerns on the application of new, rapid analytical methods for halal authentication are discussed. The significance of zero tolerance policy in consumer packaged foods and its impact on analytical testing are presented. The role of halal assurance systems and their challenges are also considered. In conclusion, consensus on the establishment of one standard approach coupled with a sound traceability system and constant monitoring would certainly improve and ensure halalness of consumer packaged goods. © 2017 Society of Chemical Industry. © 2017 Society of Chemical Industry.
NASA Astrophysics Data System (ADS)
Gaieb, Zied; Liu, Shuai; Gathiaka, Symon; Chiu, Michael; Yang, Huanwang; Shao, Chenghua; Feher, Victoria A.; Walters, W. Patrick; Kuhn, Bernd; Rudolph, Markus G.; Burley, Stephen K.; Gilson, Michael K.; Amaro, Rommie E.
2018-01-01
The Drug Design Data Resource (D3R) ran Grand Challenge 2 (GC2) from September 2016 through February 2017. This challenge was based on a dataset of structures and affinities for the nuclear receptor farnesoid X receptor (FXR), contributed by F. Hoffmann-La Roche. The dataset contained 102 IC50 values, spanning six orders of magnitude, and 36 high-resolution co-crystal structures with representatives of four major ligand classes. Strong global participation was evident, with 49 participants submitting 262 prediction submission packages in total. Procedurally, GC2 mimicked Grand Challenge 2015 (GC2015), with a Stage 1 subchallenge testing ligand pose prediction methods and ranking and scoring methods, and a Stage 2 subchallenge testing only ligand ranking and scoring methods after the release of all blinded co-crystal structures. Two smaller curated sets of 18 and 15 ligands were developed to test alchemical free energy methods. This overview summarizes all aspects of GC2, including the dataset details, challenge procedures, and participant results. We also consider implications for progress in the field, while highlighting methodological areas that merit continued development. Similar to GC2015, the outcome of GC2 underscores the pressing need for methods development in pose prediction, particularly for ligand scaffolds not currently represented in the Protein Data Bank (http://www.pdb.org), and in affinity ranking and scoring of bound ligands.
Manufacturing and Security Challenges in 3D Printing
NASA Astrophysics Data System (ADS)
Zeltmann, Steven Eric; Gupta, Nikhil; Tsoutsos, Nektarios Georgios; Maniatakos, Michail; Rajendran, Jeyavijayan; Karri, Ramesh
2016-07-01
As the manufacturing time, quality, and cost associated with additive manufacturing (AM) continue to improve, more and more businesses and consumers are adopting this technology. Some of the key benefits of AM include customizing products, localizing production and reducing logistics. Due to these and numerous other benefits, AM is enabling a globally distributed manufacturing process and supply chain spanning multiple parties, and hence raises concerns about the reliability of the manufactured product. In this work, we first present a brief overview of the potential risks that exist in the cyber-physical environment of additive manufacturing. We then evaluate the risks posed by two different classes of modifications to the AM process which are representative of the challenges that are unique to AM. The risks posed are examined through mechanical testing of objects with altered printing orientation and fine internal defects. Finite element analysis and ultrasonic inspection are also used to demonstrate the potential for decreased performance and for evading detection. The results highlight several scenarios, intentional or unintentional, that can affect the product quality and pose security challenges for the additive manufacturing supply chain.
Cell and Gene Therapies: European View on Challenges in Translation and How to Address Them
Rousseau, Cécile F.; Mačiulaitis, Romaldas; Śladowski, Dariusz; Narayanan, Gopalan
2018-01-01
Advanced therapy medicinal products (ATMPs), i.e., cell and gene therapy products, is a rapidly evolving field of therapeutic development. A significant proportion of the products are being developed by academia or small/medium-sized enterprises (SMEs). The many challenges in translation posed by this class of products include aspects covering: manufacturing, non-clinical development plan as relevant to clinical trial, marketing authorization, and reimbursement. In this context, the term translation refers to the relevance of non-clinical data in relation to how it impacts on appropriate and efficient clinical development. In order to successfully overcome these challenges, a clear understanding of the requirements and expectations of all the stakeholders is critical. This article aims to cover the potential challenges related to such translation and suggested approaches to find solutions based on experience and learnings from the perspective of European Union. While commercial challenges have a significant impact on the ATMPs in general, it is considered outside the scope of this article. However, by adopting a strong scientific basis for translation as suggested in this article, it is likely such an approach would help rather than harm successful real world clinical use of ATMPs.
Endoscopic Endonasal Management of Craniopharyngioma.
Zacharia, Brad E; Amine, Muhamad; Anand, Vijay; Schwartz, Theodore H
2016-02-01
Craniopharyngioma is a rare clinical entity that poses a significant management challenge given their location and propensity to recur. As part of a minimally disruptive treatment paradigm, the expanded endonasal approach has the potential to improve rates of resection, improve postoperative visual recovery, and minimize surgical morbidity. This article updates the otolaryngologic community on the basic principles and techniques regarding the incorporation of the endoscopic, endonasal approach in the management paradigm of craniopharyngioma. Copyright © 2016 Elsevier Inc. All rights reserved.
NASA Astrophysics Data System (ADS)
Lemons, John
1995-03-01
Problems of sustainable development and environmental protection pose a challenge to humanity unprecedented in scope and complexity. Whether and how the problems are resolved have significant implications for human and ecological well-being. In this paper, I discuss briefly recent international recommendations to promote sustainable development and environmental protection. I then offer a perspective on the roles and prospects of the university in promoting sustainable development and environmental protection.
Institutionalizing Blended Learning into Joint Training: A Case Study and Ten Recommendations
2014-12-01
mail.mil pbockelman@mesh.dsci.com ABSTRACT In 2011, the Joint Staff J7 (Joint Training) directorate initiated the Continuum of eLearning project in...Orlando, FL. 14. ABSTRACT In 2011, the Joint Staff J7 (Joint Training) directorate initiated the Continuum of eLearning project in order to integrate...dispersed organizations still poses significant challenges. The Joint Staff J7, Deputy Director for Joint Training initiated the Continuum of eLearning
Human safety in the lunar environment
NASA Technical Reports Server (NTRS)
Lewis, Robert H.
1992-01-01
Any attempt to establish a continuously staffed base or permanent settlement on the Moon must safely meet the challenges posed by the Moon's surface environment. This environment is drastically different from the Earth's, and radiation and meteoroids are significant hazards to human safety. These dangers may be mitigated through the use of underground habitats, the piling up of lunar materials as shielding, and the use of teleoperated devices for surface operations. The lunar environment is detailed along with concepts for survival.
2012-05-17
and the Northern Sea Route, extraction of potential oil and gas resources, and expanded fishing and tourism .‖ 6 The Arctic‘s vast natural resources...sudden and substantial increase in commercial shipping, marine tourism , and large passenger vessels in the Arctic poses significant challenges to the...security,‖ Huebert states that, ―Canada, Denmark, Norway, Russia and the United States have all either begun to rebuild their Arctic capabilities
SMEs and their E-Commerce: Implications for Training in Wellington, New Zealand
ERIC Educational Resources Information Center
Beal, Tim; Abdullah, Moha Asri
2005-01-01
One of the greatest challenges facing traditional small and medium-sized enterprises (SMEs) throughout the world is that posed by the Internet. While the Internet offers great potential to SMEs, from improving and cheapening production processes through to reaching global customers, it also poses great problems. SMEs' resources, human and…
Microbiological Quantitative Risk Assessment
NASA Astrophysics Data System (ADS)
Dominguez, Silvia; Schaffner, Donald W.
The meat and poultry industry faces ongoing challenges due to the natural association of pathogens of concern (e.g., Salmonella, Campylobacter jejuni, Escherichia coli O157:H7) with a variety of domesticated food animals. In addition, pathogens such as Listeria monocytogenes pose a significant cross-contamination risk during further meat and poultry processing, distribution, and storage. Furthermore, the meat and poultry industries are constantly changing with the addition of new products, use of new raw materials, and targeting of new consumer populations, each of which may give rise to potential new risks. National and international regulations are increasingly using a “risk-based” approach to food safety (where the regulatory focus is driven by the magnitude of the risk), so risk assessment is becoming a valuable tool to systematically organize and evaluate the potential public health risk posed by food processing operations.
Are Eimeria Genetically Diverse, and Does It Matter?
Clark, Emily L; Tomley, Fiona M; Blake, Damer P
2017-03-01
Eimeria pose a risk to all livestock species as a cause of coccidiosis, reducing productivity and compromising animal welfare. Pressure to reduce drug use in the food chain makes the development of cost-effective vaccines against Eimeria essential. For novel vaccines to be successful, understanding genetic and antigenic diversity in field populations is key. Eimeria species that infect chickens are most significant, with Eimeria tenella among the best studied and most economically important. Genome-wide single nucleotide polymorphism (SNP)-based haplotyping has been used to determine population structure, genotype distribution, and potential for cross-fertilization between E. tenella strains. Here, we discuss recent developments in our understanding of diversity for Eimeria in relation to its specialized life cycle, distribution across the globe, and the challenges posed to vaccine development. Copyright © 2016 Elsevier Ltd. All rights reserved.
The Marihuana Dilemma: Challenge to Commanders.
The marihuana dilemma poses a major challenge to commanders in the US Army today. The problem was analyzed as to the characteristics of the drug...available to commanders to meet the challenge. The essay concludes that marihuana should not be legalized; drug users or former drug users should not be
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…
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…
In-the-wild facial expression recognition in extreme poses
NASA Astrophysics Data System (ADS)
Yang, Fei; Zhang, Qian; Zheng, Chi; Qiu, Guoping
2018-04-01
In the computer research area, facial expression recognition is a hot research problem. Recent years, the research has moved from the lab environment to in-the-wild circumstances. It is challenging, especially under extreme poses. But current expression detection systems are trying to avoid the pose effects and gain the general applicable ability. In this work, we solve the problem in the opposite approach. We consider the head poses and detect the expressions within special head poses. Our work includes two parts: detect the head pose and group it into one pre-defined head pose class; do facial expression recognize within each pose class. Our experiments show that the recognition results with pose class grouping are much better than that of direct recognition without considering poses. We combine the hand-crafted features, SIFT, LBP and geometric feature, with deep learning feature as the representation of the expressions. The handcrafted features are added into the deep learning framework along with the high level deep learning features. As a comparison, we implement SVM and random forest to as the prediction models. To train and test our methodology, we labeled the face dataset with 6 basic expressions.
Challenges facing an understanding of the nature of low-energy excited states in photosynthesis.
Reimers, Jeffrey R; Biczysko, Malgorzata; Bruce, Douglas; Coker, David F; Frankcombe, Terry J; Hashimoto, Hideki; Hauer, Jürgen; Jankowiak, Ryszard; Kramer, Tobias; Linnanto, Juha; Mamedov, Fikret; Müh, Frank; Rätsep, Margus; Renger, Thomas; Styring, Stenbjörn; Wan, Jian; Wang, Zhuan; Wang-Otomo, Zheng-Yu; Weng, Yu-Xiang; Yang, Chunhong; Zhang, Jian-Ping; Freiberg, Arvi; Krausz, Elmars
2016-09-01
While the majority of the photochemical states and pathways related to the biological capture of solar energy are now well understood and provide paradigms for artificial device design, additional low-energy states have been discovered in many systems with obscure origins and significance. However, as low-energy states are naively expected to be critical to function, these observations pose important challenges. A review of known properties of low energy states covering eight photochemical systems, and options for their interpretation, are presented. A concerted experimental and theoretical research strategy is suggested and outlined, this being aimed at providing a fully comprehensive understanding. Copyright © 2016 Elsevier B.V. All rights reserved.
Weerasundera, Rajiv; Yogaratnam, Jegan
2013-01-01
Psychotic illness has a low incidence in the puerperal period. Peripartum cardiomyopathy as a complication of pregnancy is also rare. We report a case where the above two conditions occurred simultaneously in a patient and posed significant difficulties in the clinical management. She was diagnosed as having paranoid schizophrenia and peripartum cardiomyopathy. Many of the antipsychotics were contraindicated, and electroconvulsive therapy could not be administered due to the added risks involved with regard to anesthesia. She was therefore managed with clonazepam and olanzapine. This case highlights the challenges in a patient with a psychiatric illness presenting with comorbid physical illness. Copyright © 2013 Elsevier Inc. All rights reserved.
Extinction debt: a challenge for biodiversity conservation.
Kuussaari, Mikko; Bommarco, Riccardo; Heikkinen, Risto K; Helm, Aveliina; Krauss, Jochen; Lindborg, Regina; Ockinger, Erik; Pärtel, Meelis; Pino, Joan; Rodà, Ferran; Stefanescu, Constantí; Teder, Tiit; Zobel, Martin; Steffan-Dewenter, Ingolf
2009-10-01
Local extinction of species can occur with a substantial delay following habitat loss or degradation. Accumulating evidence suggests that such extinction debts pose a significant but often unrecognized challenge for biodiversity conservation across a wide range of taxa and ecosystems. Species with long generation times and populations near their extinction threshold are most likely to have an extinction debt. However, as long as a species that is predicted to become extinct still persists, there is time for conservation measures such as habitat restoration and landscape management. Standardized long-term monitoring, more high-quality empirical studies on different taxa and ecosystems and further development of analytical methods will help to better quantify extinction debt and protect biodiversity.
Efficient computation of hashes
NASA Astrophysics Data System (ADS)
Lopes, Raul H. C.; Franqueira, Virginia N. L.; Hobson, Peter R.
2014-06-01
The sequential computation of hashes at the core of many distributed storage systems and found, for example, in grid services can hinder efficiency in service quality and even pose security challenges that can only be addressed by the use of parallel hash tree modes. The main contributions of this paper are, first, the identification of several efficiency and security challenges posed by the use of sequential hash computation based on the Merkle-Damgard engine. In addition, alternatives for the parallel computation of hash trees are discussed, and a prototype for a new parallel implementation of the Keccak function, the SHA-3 winner, is introduced.
The European flood risk directive: challenges for research
NASA Astrophysics Data System (ADS)
Mostert, E.; Junier, S. J.
2009-07-01
In recent years, flood management has shifted from protection against floods to managing the risks of floods. In Europe, this shift is reflected in the Flood risk directive of October 2007 (2007/60/EC; FRD). The FRD requires EU Member States to undertake a preliminary assessment of flood risks and, for areas with a significant flood risk, to prepare flood hazard and flood risk maps and flood risk management plans. The purpose of this paper is to introduce the FRD and discuss the challenges that the FRD poses to research. These challenges include the issue how to define and measure ''flood risk'', the selection of alternatives to be assessed, coping with uncertainty, risk communication, nurturing trust and promoting collaboration. These research challenges cannot be addressed properly within any single discipline and without involving the flood risk managers and other stakeholders. The paper therefore concludes that there is a large need for interdisciplinary and participatory research. This constitutes in fact the biggest research challenge.
Head pose estimation in computer vision: a survey.
Murphy-Chutorian, Erik; Trivedi, Mohan Manubhai
2009-04-01
The capacity to estimate the head pose of another person is a common human ability that presents a unique challenge for computer vision systems. Compared to face detection and recognition, which have been the primary foci of face-related vision research, identity-invariant head pose estimation has fewer rigorously evaluated systems or generic solutions. In this paper, we discuss the inherent difficulties in head pose estimation and present an organized survey describing the evolution of the field. Our discussion focuses on the advantages and disadvantages of each approach and spans 90 of the most innovative and characteristic papers that have been published on this topic. We compare these systems by focusing on their ability to estimate coarse and fine head pose, highlighting approaches that are well suited for unconstrained environments.
Development of vaccines for bio-warfare agents.
Rosenthal, S R; Clifford, J C M
2002-01-01
There is a recognized need for the development of new vaccines (as well as other biologicals and drugs) to counteract the effects of a potential bio-terrorist or bio-warfare event in the U.S. domestic population and military forces. Regulation of products to protect against potential bio-warfare agents poses unique challenges since the usual measures of efficacy that require exposure to natural disease may not currently be possible, for epidemiological and ethical reasons. To help to address this issue, the FDA has published and requested comments on a proposed animal rule intended to address certain efficacy issues for new agents for use against lethal or permanently disabling toxic substances. Recent product development activity has focused on Bacillus anthracis (anthrax) and variola major (smallpox), agents that are regarded as highest priority in posing a risk to national security. FDA resources exist to assist vaccine developers with regard to the novel challenges posed in the dinical development of these products.
Exploring the stability of ligand binding modes to proteins by molecular dynamics simulations.
Liu, Kai; Watanabe, Etsurou; Kokubo, Hironori
2017-02-01
The binding mode prediction is of great importance to structure-based drug design. The discrimination of various binding poses of ligand generated by docking is a great challenge not only to docking score functions but also to the relatively expensive free energy calculation methods. Here we systematically analyzed the stability of various ligand poses under molecular dynamics (MD) simulation. First, a data set of 120 complexes was built based on the typical physicochemical properties of drug-like ligands. Three potential binding poses (one correct pose and two decoys) were selected for each ligand from self-docking in addition to the experimental pose. Then, five independent MD simulations for each pose were performed with different initial velocities for the statistical analysis. Finally, the stabilities of ligand poses under MD were evaluated and compared with the native one from crystal structure. We found that about 94% of the native poses were maintained stable during the simulations, which suggests that MD simulations are accurate enough to judge most experimental binding poses as stable properly. Interestingly, incorrect decoy poses were maintained much less and 38-44% of decoys could be excluded just by performing equilibrium MD simulations, though 56-62% of decoys were stable. The computationally-heavy binding free energy calculation can be performed only for these survived poses.
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.
Improving and Accelerating Drug Development for Nervous System Disorders
Pankevich, Diana E.; Altevogt, Bruce M.; Dunlop, John; Gage, Fred H.; Hyman, Steve E.
2014-01-01
Advances in the neurosciences have placed the field in the position where it is poised to significantly reduce the burden of nervous system disorders. However, drug discovery, development and translation for nervous system disorders still pose many unique challenges. The key scientific challenges can be summarized as follows: mechanisms of disease, target identification and validation, predictive models, biomarkers for patient stratification and as endpoints for clinical trials, clear regulatory pathways, reliability and reproducibility of published data, and data sharing and collaboration. To accelerate nervous system drug development the Institute of Medicine’s Forum on Neuroscience and Nervous System Disorders has hosted a series of public workshops that brought together representatives of industry, government (including both research funding and regulatory agencies), academia, and patient groups to discuss these challenges and offer potential strategies to improve the translational neuroscience. PMID:25442933
Communicating about smoke from wildland fire: challenges and ways to address them
Christine S. Olsen; Danielle K. Mazzotta; Eric Toman; A. Paige Fischer
2014-01-01
Wildland fire and associated management efforts are dominant topics in natural resource fields. Smoke from fires can be a nuisance and pose serious health risks and aggravate pre-existing health conditions. When it results in reduced visibility near roadways, smoke can also pose hazardous driving conditions and reduce the scenic value of vistas. Communicating about...
Tracking the Careers of Graduates: A New Agenda for Graduate Schools
ERIC Educational Resources Information Center
Stewart, Debra W.
2013-01-01
As candidates in the 2012 election debated issues raised by the state of the US economy, unemployment statistics and job creation took center stage. The problems under discussion posed (and continue to pose) a particularly clear and pressing challenge to the nation's graduate schools. While the US enjoys a reputation for having the most dynamic…
ERIC Educational Resources Information Center
Wang, Xiao-Ming; Hwang, Gwo-Jen
2017-01-01
Computer programming is a subject that requires problem-solving strategies and involves a great number of programming logic activities which pose challenges for learners. Therefore, providing learning support and guidance is important. Collaborative learning is widely believed to be an effective teaching approach; it can enhance learners' social…
Incorporating Qualitative Evidence in Systematic Reviews: Strategies and Challenges
ERIC Educational Resources Information Center
Caracelli, Valerie J.; Cooksy, Leslie J.
2013-01-01
The quality of mixed methods systematic reviews relies on the quality of primary-level studies. The synthesis of qualitative evidence and the recent development of synthesizing mixed methods studies hold promise, but also pose challenges to evidence synthesis.
Variation in Transpiration Efficiency in Sorghum
USDA-ARS?s Scientific Manuscript database
Declining freshwater resources, increasing population, and growing demand for biofuels pose new challenges for agriculture research. To meet these challenges, the concept "Blue Revolution" (more crop per drop) was proposed to improve water productivity in agriculture. We have identified several so...
Anaesthetic significance and management of a child with neonatal purpura fulminans
Tiwari, Akhilesh Kumar; Tomar, Gaurav Singh; Tayal, Swapnil; Chadha, Madhur; Kapoor, Mukul
2012-01-01
Protein C deficiency is a rare autosomal-dominant disorder of varying severity. Patients with homozygous and compound heterozygous protein C deficiency present with neonatal purpura fulminans (NPF). Other presentations usually include disseminated intravascular coagulation and venous thromboembolism. This disorder usually poses a unique anaesthetic challenge to the anaesthesiologist, requiring special precautions to prevent various intra- and post-operative complications. We hereby report the successful anaesthetic management of a 1-month-old infant who presented with NPF. PMID:22923829
Crohn's disease presenting as acute gastrointestinal hemorrhage
Podugu, Amareshwar; Tandon, Kanwarpreet; Castro, Fernando J
2016-01-01
Severe gastrointestinal (GI) hemorrhage is a rare complication of Crohn’s disease (CD). Although several surgical and non-surgical approaches have been described over the last 2 decades this complication still poses significant diagnostic and therapeutic challenges. Given the relative infrequency of severe bleeding in CD, available medical literature on this topic is mostly in the form of retrospective case series and reports. In this article we review the risk factors, diagnostic modalities and treatment options for the management of CD presenting as GI hemorrhage. PMID:27122659
NASA Astrophysics Data System (ADS)
Hoch, Jeffrey C.
2017-10-01
Non-Fourier methods of spectrum analysis are gaining traction in NMR spectroscopy, driven by their utility for processing nonuniformly sampled data. These methods afford new opportunities for optimizing experiment time, resolution, and sensitivity of multidimensional NMR experiments, but they also pose significant challenges not encountered with the discrete Fourier transform. A brief history of non-Fourier methods in NMR serves to place different approaches in context. Non-Fourier methods reflect broader trends in the growing importance of computation in NMR, and offer insights for future software development.
Memory management in genome-wide association studies
2009-01-01
Genome-wide association is a powerful tool for the identification of genes that underlie common diseases. Genome-wide association studies generate billions of genotypes and pose significant computational challenges for most users including limited computer memory. We applied a recently developed memory management tool to two analyses of North American Rheumatoid Arthritis Consortium studies and measured the performance in terms of central processing unit and memory usage. We conclude that our memory management approach is simple, efficient, and effective for genome-wide association studies. PMID:20018047
ERIC Educational Resources Information Center
Papay, John P.; Bacher-Hicks, Andrew; Page, Lindsay C.; Marinell, William H.
2017-01-01
Substantial teacher turnover poses a challenge to staffing public schools with effective teachers. The scope of the teacher retention challenge across school districts, however, remains poorly defined. Applying consistent data practices and analytical techniques to administrative data sets from 16 urban districts, we document substantial…
The Enduring Challenges in Public Management: Surviving and Excelling in a Changing World.
ERIC Educational Resources Information Center
Halachmi, Arie, Ed.; Bouckaert, Geert, Ed.
This book addresses in different ways the prospect of improving the performance of government and nonprofit organizations. The chapters are clustered around enduring management challenges that may influence productivity in the public sector. Fifteen chapters discuss the challenges to productivity posed by immediate and distant changes in the…
Influenza Vaccines: Challenges and Solutions
Houser, Katherine; Subbarao, Kanta
2015-01-01
Vaccination is the best method for the prevention and control of influenza. Vaccination can reduce illness and lessen severity of infection. This review focuses on how currently licensed influenza vaccines are generated in the U.S., why the biology of influenza poses vaccine challenges, and vaccine approaches on the horizon that address these challenges. PMID:25766291
Human pose tracking from monocular video by traversing an image motion mapped body pose manifold
NASA Astrophysics Data System (ADS)
Basu, Saurav; Poulin, Joshua; Acton, Scott T.
2010-01-01
Tracking human pose from monocular video sequences is a challenging problem due to the large number of independent parameters affecting image appearance and nonlinear relationships between generating parameters and the resultant images. Unlike the current practice of fitting interpolation functions to point correspondences between underlying pose parameters and image appearance, we exploit the relationship between pose parameters and image motion flow vectors in a physically meaningful way. Change in image appearance due to pose change is realized as navigating a low dimensional submanifold of the infinite dimensional Lie group of diffeomorphisms of the two dimensional sphere S2. For small changes in pose, image motion flow vectors lie on the tangent space of the submanifold. Any observed image motion flow vector field is decomposed into the basis motion vector flow fields on the tangent space and combination weights are used to update corresponding pose changes in the different dimensions of the pose parameter space. Image motion flow vectors are largely invariant to style changes in experiments with synthetic and real data where the subjects exhibit variation in appearance and clothing. The experiments demonstrate the robustness of our method (within +/-4° of ground truth) to style variance.
Ghosh, S; Smith, M H; Rap, A
2007-11-15
Aerosols are known to influence significantly the radiative budget of the Earth. Although the direct effect (whereby aerosols scatter and absorb solar and thermal infrared radiation) has a large perturbing influence on the radiation budget, the indirect effect (whereby aerosols modify the microphysical and hence the radiative properties and amounts of clouds) poses a greater challenge to climate modellers. This is because aerosols undergo chemical and physical changes while in the atmosphere, notably within clouds, and are removed largely by precipitation. The way in which aerosols are processed by clouds depends on the type, abundance and the mixing state of the aerosols concerned. A parametrization with sulphate and sea-salt aerosol has been successfully integrated within the Hadley Centre general circulation model (GCM). The results of this combined parametrization indicate a significantly reduced role, compared with previous estimates, for sulphate aerosol in cloud droplet nucleation and, consequently, in indirect radiative forcing. However, in this bicomponent system, the cloud droplet number concentration, N(d) (a crucial parameter that is used in GCMs for radiative transfer calculations), is a smoothly varying function of the sulphate aerosol loading. Apart from sea-salt and sulphate aerosol particles, biomass aerosol particles are also present widely in the troposphere. We find that biomass smoke can significantly perturb the activation and growth of both sulphate and sea-salt particles. For a fixed salt loading, N(d) increases linearly with modest increases in sulphate and smoke masses, but significant nonlinearities are observed at higher non-sea-salt mass loadings. This non-intuitive N(d) variation poses a fresh challenge to climate modellers.
RECRUITMENT STRATEGIES FOR AN EXPOSURE MEASUREMENT STUDY OF PRESCHOOL CHILDREN
Recruiting study participants is always a challenge for researchers. It poses an even bigger challenge for researchers to recruit participants for a study involving intrusive, burdensome data collection activities. A study of preschool children's exposure to persistent organic ...
This is a webinar page for the Sustainable Management of Materials (SMM) Web Academy webinar titled, An Introduction to Lithium Batteries and the Challenges that they Pose to the Waste and Recycling Industry.
De Santo, Elizabeth M
2013-07-30
International targets for marine protected areas (MPAs) and networks of MPAs set by the World Summit on Sustainable Development and United Nations Convention on Biological Diversity failed to meet their 2012 deadline and have been extended to 2020. Whilst targets play an important role in building momentum for conservation, they are also responsible for the recent designation of several extremely large no-take MPAs, which pose significant long-term monitoring and enforcement challenges. This paper critically examines the effectiveness of MPA targets, focusing on the underlying risks to achieving Millennium Development Goals posed by the global push for quantity versus quality of MPAs. The observations outlined in this paper have repercussions for international protected area politics with respect to (1) the science-policy interface in environmental decision-making, and (2) social justice concerns in global biodiversity conservation. Copyright © 2013 Elsevier Ltd. All rights reserved.
2013-01-01
Background Patients engage in medical tourism when they privately obtain a medical care abroad. Previous research shows that many medical tourists travel abroad with friends and family members who provide support and assistance. Meanwhile, very little is known about this important stakeholder group, referred to here as caregiver-companions. In this article we examine the challenges that can be posed by caregiver-companions and the overall practice of informal caregiving in medical tourism from an industry perspective. Specifically, we report on the findings of interviews conducted with international patient coordinators (IPCs) who work at destination facilities. IPCs come into regular contact with caregiver-companions in their professional positions and thus are ideally suited to comment on trends they have observed among this stakeholder group as well as the challenges they can pose to medical tourists, health workers, and facilities. Methods We conducted 20 semi-structured interviews with 21 IPCs from 16 different facilities across nine countries. Topics probed in the interviews included caregiver-companion roles, IPCs’ and others’ interaction with caregiver-companions, and potential health and safety risks posed to medical tourists and caregiver-companions. Thematic analysis of the verbatim transcripts was employed. Results Although most participants encouraged medical tourists to travel with a caregiver-companion, many challenges associated with caregiver-companions were identified. Three themes best characterize the challenges that emerged: (1) caregiver-companions require time, attention and resources; (2) caregiver-companions can disrupt the provision of quality care; and (3) caregiver-companions can be exposed to risks. IPCs pointed out that caregiver-companions may, for example, have a negative impact on the patient through cost of accompaniment or inadequate care provision. Caregiver-companions may also create unanticipated or extra work for IPCs, as additional clients and by ignoring established organizational rules, routines, and expectations. Furthermore, caregiver-companions may be susceptible to stresses and health and safety risks, which would further deteriorate their own abilities to offer the patient quality care. Conclusions Although caregiver-companions can pose challenges to medical tourists, health workers, and medical tourism facilities, they can also assist in enhancing best care and offering meaningful support to medical tourists. If caregiver-companions are open to collaboration with IPCs, and particularly in the form of information sharing, then their experience abroad can be safer and less stressful for themselves and, by extension, for the accompanied patients and facility staff. PMID:23889860
Casey, Victoria; Crooks, Valorie A; Snyder, Jeremy; Turner, Leigh
2013-07-26
Patients engage in medical tourism when they privately obtain a medical care abroad. Previous research shows that many medical tourists travel abroad with friends and family members who provide support and assistance. Meanwhile, very little is known about this important stakeholder group, referred to here as caregiver-companions. In this article we examine the challenges that can be posed by caregiver-companions and the overall practice of informal caregiving in medical tourism from an industry perspective. Specifically, we report on the findings of interviews conducted with international patient coordinators (IPCs) who work at destination facilities. IPCs come into regular contact with caregiver-companions in their professional positions and thus are ideally suited to comment on trends they have observed among this stakeholder group as well as the challenges they can pose to medical tourists, health workers, and facilities. We conducted 20 semi-structured interviews with 21 IPCs from 16 different facilities across nine countries. Topics probed in the interviews included caregiver-companion roles, IPCs' and others' interaction with caregiver-companions, and potential health and safety risks posed to medical tourists and caregiver-companions. Thematic analysis of the verbatim transcripts was employed. Although most participants encouraged medical tourists to travel with a caregiver-companion, many challenges associated with caregiver-companions were identified. Three themes best characterize the challenges that emerged: (1) caregiver-companions require time, attention and resources; (2) caregiver-companions can disrupt the provision of quality care; and (3) caregiver-companions can be exposed to risks. IPCs pointed out that caregiver-companions may, for example, have a negative impact on the patient through cost of accompaniment or inadequate care provision. Caregiver-companions may also create unanticipated or extra work for IPCs, as additional clients and by ignoring established organizational rules, routines, and expectations. Furthermore, caregiver-companions may be susceptible to stresses and health and safety risks, which would further deteriorate their own abilities to offer the patient quality care. Although caregiver-companions can pose challenges to medical tourists, health workers, and medical tourism facilities, they can also assist in enhancing best care and offering meaningful support to medical tourists. If caregiver-companions are open to collaboration with IPCs, and particularly in the form of information sharing, then their experience abroad can be safer and less stressful for themselves and, by extension, for the accompanied patients and facility staff.
Current challenges in organic photovoltaic solar energy conversion.
Schlenker, Cody W; Thompson, Mark E
2012-01-01
Over the last 10 years, significant interest in utilizing conjugated organic molecules for solid-state solar to electric conversion has produced rapid improvement in device efficiencies. Organic photovoltaic (OPV) devices are attractive for their compatibility with low-cost processing techniques and thin-film applicability to flexible and conformal applications. However, many of the processes that lead to power losses in these systems still remain poorly understood, posing a significant challenge for the future efficiency improvements required to make these devices an attractive solar technology. While semiconductor band models have been employed to describe OPV operation, a more appropriate molecular picture of the pertinent processes is beginning to emerge. This chapter presents mechanisms of OPV device operation, based on the bound molecular nature of the involved transient species. With the intention to underscore the importance of considering both thermodynamic and kinetic factors, recent progress in elucidating molecular characteristics that dictate photovoltage losses in heterojunction organic photovoltaics is also discussed.
Respiratory health in Latin America: number of specialists and human resources training.
Vázquez-García, Juan-Carlos; Salas-Hernández, Jorge; Pérez Padilla, Rogelio; Montes de Oca, María
2014-01-01
Latin America is made up of a number of developing countries. Demographic changes are occurring in the close to 600 million inhabitants, in whom a significant growth in population is combined with the progressive ageing of the population. This part of the world poses great challenges for general and respiratory health. Most of the countries have significant, or even greater, rates of chronic respiratory diseases or exposure to risk. Human resources in healthcare are not readily available, particularly in the area of respiratory disease specialists. Academic training centers are few and even non-existent in the majority of the countries. The detailed analysis of these conditions provides a basis for reflection on the main challenges and proposals for the management and training of better human resources in this specialist area. Copyright © 2013 SEPAR. Published by Elsevier Espana. All rights reserved.
ERIC Educational Resources Information Center
Park, Travis; Pearson, Donna; Richardson, George B.
2017-01-01
All students need to learn how to read, write, solve mathematics problems, and understand and apply scientific principles to succeed in college and/or careers. The challenges posed by entry-level career fields are no less daunting than those posed by college-level study. Thus, career and technical education students must learn effective math,…
National Security and Global Climate Change
2008-01-01
The uncertainty, confusion, and speculation about the causes, effects, and implications of global climate change (GCC) often paralyze serious...against scientific indications of global climate change , but to consider how it would pose challenges to national security, explore options for facing...generals and admirals, released a report concluding that projected climate change poses a serious threat to America’s national security. This article
The Development of Questioning as a Means of Framing Problems and Posing Challenges.
ERIC Educational Resources Information Center
Feigenbaum, Peter
When a person encounters a problem, the character, form, and content of his or her response provides psychologists with useful and interesting information about processes of challenge and their relationship to intellectual development. In essence, challenge is a developing relationship that is defined on the one hand by objective factors (a person…
Social Software: A Powerful Paradigm for Building Technology for Global Learning
ERIC Educational Resources Information Center
Wooding, Amy; Wooding, Kjell
2018-01-01
It is not difficult to imagine a world where internet-connected mobile devices are accessible to everyone. Can these technologies be used to help solve the challenges of global education? This was the challenge posed by the Global Learning XPRIZE--a $15 million grand challenge competition aimed at addressing this global teaching shortfall. In…
Current Developments and Challenges in the Search for a Naturally Selected Diels-Alderase
Kim, Hak Joong; Ruszczycky, Mark W.; Liu, Hung-wen
2012-01-01
Only a very few examples of enzymes known to catalyze pericyclic reactions have been reported, and presently no enzyme has been demonstrated unequivocally to catalyze a Diels-Alder reaction. Nevertheless, research into secondary metabolism has led to the discovery of numerous natural products exhibiting the structural hallmarks of [4+2] cycloadditions, prompting efforts to characterize the responsible enzymatic processes. These efforts have resulted in a growing collection of enzymes believed to catalyze pericyclic [4+2] cycloaddition reactions; however, in each case the complexity of the substrates and catalytic properties of these enzymes poses significant challenges in substantiating these hypotheses. Herein we consider the principles motivating these efforts and the enzymological systems currently under investigation. PMID:22260931
The Unifying Principle of Coordinated Measurements in Geospace Science
NASA Astrophysics Data System (ADS)
Lotko, William
2017-04-01
Space scientists recognize geospace as a coupled dynamical system extending from the Earth's upper atmosphere, ionosphere, and magnetosphere, through interplanetary space to the Sun. The weather in geospace describes variability in the electromagnetic fields, particle radiation, plasmas, and gases permeating it, usually in response to solar disturbances. Severe space weather poses a significant threat to human activities in space and to modern technological systems deployed both in space and at Earth. The challenge of characterizing and predicting space weather requires widely distributed, coordinated observations. Partnerships among government agencies, international consortia, and the private sector are developing creative solutions to address this challenge. This brief commentary highlights some of the coordinated measurements and data systems that are unifying knowledge of the geospace environment.
Myostatin and sarcopenia: opportunities and challenges - a mini-review.
White, Thomas A; LeBrasseur, Nathan K
2014-01-01
The progressive loss of skeletal muscle mass, strength and/or function with advancing age, termed sarcopenia, poses a major threat to independence and quality of life. Therefore, there is significant merit in better understanding the biology of sarcopenia and developing therapeutic interventions to prevent, slow or reverse its progression. Since the discovery of myostatin, a potent negative regulator of growth that is highly enriched in skeletal muscle, there has been great interest in it as a potential mediator of sarcopenia as well as a therapeutic target. The complex biology of myostatin, the promise of myostatin inhibition as an effective means to counter sarcopenia, and the challenges facing its clinical translation are reviewed herein. © 2014 S. Karger AG, Basel.
ERIC Educational Resources Information Center
Jackson, M. G.
2011-01-01
Between the Inter-governmental Conference on Environmental Education at Tbilisi in 1977 and the Fourth International Conference on Environmental Education at Ahmedabad in 2007, our conception of the challenge posed by the global crises of climate change, environmental destruction, social disintegration, poverty, natural resources exhaustion and…
DEVELOPMENT, DESIGN AND CONSUMER TESTING OF MARKETABLE RESIDENTIAL LED LIGHT LUMINAIRES
Developing marketable LED luminaires poses challenges, even though LEDs are energy-efficient and an ecological alternative to conventionally lighting. Challenges include: perceptions that the color rendition of LEDs is unacceptable to the public; numbers of LEDs must be grou...
Variation in transpiration efficiency in sorghum
USDA-ARS?s Scientific Manuscript database
Declining freshwater resources, increasing population, and growing demand for biofuels pose new challenges for agriculture research. To meet these challenges, the concept “Blue Revolution” was proposed to improve water productivity in agriculture--“More Crop per Drop”. Sorghum is the fifth most imp...
Variation of Transpiration Efficiency in Sorghum
USDA-ARS?s Scientific Manuscript database
Declining freshwater resources, increasing population, and growing demand for biofuels pose new challenges for agriculture research. To meet these challenges, the concept “Blue Revolution” was proposed to improve water productivity in agriculture--“More Crop per Drop”. Sorghum is the fifth most imp...
Irritable bowel syndrome in children: Current knowledge, challenges and opportunities
Devanarayana, Niranga Manjuri; Rajindrajith, Shaman
2018-01-01
Irritable bowel syndrome (IBS) is a common and troublesome disorder in children with an increasing prevalence noted during the past two decades. It has a significant effect on the lives of affected children and their families and poses a significant burden on healthcare systems. Standard symptom-based criteria for diagnosis of pediatric IBS have changed several times during the past two decades and there are some differences in interpreting symptoms between different cultures. This has posed a problem when using them to diagnose IBS in clinical practice. A number of potential patho-physiological mechanisms have been described, but so far the exact underlying etiology of IBS is unclear. A few potential therapeutic modalities have been tested in children and only a small number of them have shown some benefit. In addition, most of the described patho-physiological mechanisms and treatment options are based on adult studies. These have surfaced as challenges when dealing with pediatric IBS and they need to be overcome for effective management of children with IBS. Recently suggested top-down and bottom-up models help integrating reported patho-physiological mechanisms and will provide an opportunity for better understanding of the diseases process. Treatment trials targeting single treatment modalities are unlikely to have clinically meaningful therapeutic effects on IBS with multiple integrating patho-physiologies. Trials focusing on multiple combined pharmacological and non-pharmacological therapies are likely to yield more benefit. In addition to treatment, in the future, attention should be paid for possible prevention strategies for IBS. PMID:29881232
Comparative assessment of techniques for initial pose estimation using monocular vision
NASA Astrophysics Data System (ADS)
Sharma, Sumant; D`Amico, Simone
2016-06-01
This work addresses the comparative assessment of initial pose estimation techniques for monocular navigation to enable formation-flying and on-orbit servicing missions. Monocular navigation relies on finding an initial pose, i.e., a coarse estimate of the attitude and position of the space resident object with respect to the camera, based on a minimum number of features from a three dimensional computer model and a single two dimensional image. The initial pose is estimated without the use of fiducial markers, without any range measurements or any apriori relative motion information. Prior work has been done to compare different pose estimators for terrestrial applications, but there is a lack of functional and performance characterization of such algorithms in the context of missions involving rendezvous operations in the space environment. Use of state-of-the-art pose estimation algorithms designed for terrestrial applications is challenging in space due to factors such as limited on-board processing power, low carrier to noise ratio, and high image contrasts. This paper focuses on performance characterization of three initial pose estimation algorithms in the context of such missions and suggests improvements.
Robust head pose estimation via supervised manifold learning.
Wang, Chao; Song, Xubo
2014-05-01
Head poses can be automatically estimated using manifold learning algorithms, with the assumption that with the pose being the only variable, the face images should lie in a smooth and low-dimensional manifold. However, this estimation approach is challenging due to other appearance variations related to identity, head location in image, background clutter, facial expression, and illumination. To address the problem, we propose to incorporate supervised information (pose angles of training samples) into the process of manifold learning. The process has three stages: neighborhood construction, graph weight computation and projection learning. For the first two stages, we redefine inter-point distance for neighborhood construction as well as graph weight by constraining them with the pose angle information. For Stage 3, we present a supervised neighborhood-based linear feature transformation algorithm to keep the data points with similar pose angles close together but the data points with dissimilar pose angles far apart. The experimental results show that our method has higher estimation accuracy than the other state-of-art algorithms and is robust to identity and illumination variations. Copyright © 2014 Elsevier Ltd. All rights reserved.
Biomimetics and the Development of Humanlike Robots as the Ultimate Challenge
NASA Technical Reports Server (NTRS)
Bar-Cohen, Yoseph
2011-01-01
Evolution led to effective solutions to nature's challenges and they were improved over millions of years. Humans have always made efforts to use nature as a model for innovation and problems solving. These efforts became more intensive in recent years where systematic studies of nature are being made towards better understanding and applying more sophisticated capabilities. Making humanlike robots, including the appearance, functions and intelligence, poses the ultimate challenges to biomimetics. For many years, making such robots was considered science fiction, but as a result of significant advances in biologically inspired technologies, such robots are increasingly becoming an engineering reality. There are already humanlike robots that walk, talk, interpret speech, make eye-contact and facial expressions, as well as perform many other humanlike functions. In this paper, the state-of-the-art of humanlike robots, potential applications and issues of concern will be reviewed.
Self-deconstructing algae biomass as feedstock for transportation fuels
DOE Office of Scientific and Technical Information (OSTI.GOV)
Davis, Ryan Wesley
The potential for producing biofuels from algae has generated much excitement based on projections of large oil yields with relatively little land use. However, numerous technical challenges remain for achieving market parity with conventional non-renewable liquid fuel sources. Among these challenges, the energy intensive requirements of traditional cell rupture, lipid extraction, and residuals fractioning of microalgae biomass have posed significant challenges to the nascent field of algal biotechnology. Our novel approach to address these problems was to employ low cost solution-state methods and biochemical engineering to eliminate the need for extensive hardware and energy intensive methods for cell rupture, carbohydratemore » and protein solubilization and hydrolysis, and fuel product recovery using consolidated bioprocessing strategies. The outcome of the biochemical deconstruction and conversion process consists of an emulsion of algal lipids and mixed alcohol products from carbohydrate and protein fermentation for co-extraction or in situ transesterification.« less
The Critical Care Obesity Paradox and Implications for Nutrition Support.
Patel, Jayshil J; Rosenthal, Martin D; Miller, Keith R; Codner, Panna; Kiraly, Laszlo; Martindale, Robert G
2016-09-01
Obesity is a leading cause of preventable death worldwide. The prevalence of obesity has been increasing and is associated with an increased risk for other co-morbidities. In the critical care setting, nearly one third of patients are obese. Obese critically ill patients pose significant physical and on-physical challenges to providers, including optimization of nutrition therapy. Intuitively, obese patients would have worse critical care-related outcome. On the contrary, emerging data suggests that critically ill obese patients have improved outcomes, and this phenomenon has been coined "the obesity paradox." The purposes of this review will be to outline the historical views and pathophysiology of obesity and epidemiology of obesity, describe the challenges associated with obesity in the intensive care unit setting, review critical care outcomes in the obese, define the obesity-critical care paradox, and identify the challenges and role of nutrition support in the critically ill obese patient.
Ethics and Research with Undergraduates
ERIC Educational Resources Information Center
Richman, Kenneth A.; Alexander, Leslie B.
2006-01-01
Ethicists, researchers and policy makers have paid increasing attention to the ethical conduct of research, especially research involving human beings. Research performed with and by undergraduates poses a specific set of ethical challenges. These challenges are often overlooked by the research community because it is assumed that undergraduate…
Jesuit "Eloquentia Perfecta" and Theotropic Logology
ERIC Educational Resources Information Center
Mailloux, Steven
2015-01-01
This essay takes a rhetorical pragmatist perspective on current questions concerning educational goals and pedagogical practices. It begins by considering some challenges to rhetorical approaches to education, placing those challenges in the theoretical context of their posing. The essay then describes one current rhetorical approach--based on…
ERIC Educational Resources Information Center
Schleicher, Andreas
2016-01-01
The OECD Programme for International Student Assessment (PISA) provides a framework in which over 80 countries collaborate to build advanced global metrics to assess the knowledge, skills and character attributes of the students. The design of assessments poses major conceptual and technical challenges, as successful learning. Beyond a sound…
Emerging and Neglected Infectious Diseases: Insights, Advances, and Challenges
2017-01-01
Infectious diseases are a significant burden on public health and economic stability of societies all over the world. They have for centuries been among the leading causes of death and disability and presented growing challenges to health security and human progress. The threat posed by infectious diseases is further deepened by the continued emergence of new, unrecognized, and old infectious disease epidemics of global impact. Over the past three and half decades at least 30 new infectious agents affecting humans have emerged, most of which are zoonotic and their origins have been shown to correlate significantly with socioeconomic, environmental, and ecological factors. As these factors continue to increase, putting people in increased contact with the disease causing pathogens, there is concern that infectious diseases may continue to present a formidable challenge. Constant awareness and pursuance of effective strategies for controlling infectious diseases and disease emergence thus remain crucial. This review presents current updates on emerging and neglected infectious diseases and highlights the scope, dynamics, and advances in infectious disease management with particular focus on WHO top priority emerging infectious diseases (EIDs) and neglected tropical infectious diseases. PMID:28286767
Emerging and Neglected Infectious Diseases: Insights, Advances, and Challenges.
Nii-Trebi, Nicholas Israel
2017-01-01
Infectious diseases are a significant burden on public health and economic stability of societies all over the world. They have for centuries been among the leading causes of death and disability and presented growing challenges to health security and human progress. The threat posed by infectious diseases is further deepened by the continued emergence of new, unrecognized, and old infectious disease epidemics of global impact. Over the past three and half decades at least 30 new infectious agents affecting humans have emerged, most of which are zoonotic and their origins have been shown to correlate significantly with socioeconomic, environmental, and ecological factors. As these factors continue to increase, putting people in increased contact with the disease causing pathogens, there is concern that infectious diseases may continue to present a formidable challenge. Constant awareness and pursuance of effective strategies for controlling infectious diseases and disease emergence thus remain crucial. This review presents current updates on emerging and neglected infectious diseases and highlights the scope, dynamics, and advances in infectious disease management with particular focus on WHO top priority emerging infectious diseases (EIDs) and neglected tropical infectious diseases.
Rajão, Daniela S.; Pérez, Daniel R.
2018-01-01
Influenza virus infections pose a significant threat to public health due to annual seasonal epidemics and occasional pandemics. Influenza is also associated with significant economic losses in animal production. The most effective way to prevent influenza infections is through vaccination. Current vaccine programs rely heavily on the vaccine's ability to stimulate neutralizing antibody responses to the hemagglutinin (HA) protein. One of the biggest challenges to an effective vaccination program lies on the fact that influenza viruses are ever-changing, leading to antigenic drift that results in escape from earlier immune responses. Efforts toward overcoming these challenges aim at improving the strength and/or breadth of the immune response. Novel vaccine technologies, the so-called universal vaccines, focus on stimulating better cross-protection against many or all influenza strains. However, vaccine platforms or manufacturing technologies being tested to improve vaccine efficacy are heterogeneous between different species and/or either tailored for epidemic or pandemic influenza. Here, we discuss current vaccines to protect humans and animals against influenza, highlighting challenges faced to effective and uniform novel vaccination strategies and approaches. PMID:29467737
The challenges associated with developing science-based landscape scale management plans.
Robert C. Szaro; Douglas A. Jr. Boyce; Thomas Puchlerz
2005-01-01
Planning activities over large landscapes poses a complex of challenges when trying to balance the implementation of a conservation strategy while still allowing for a variety of consumptive and nonconsumptive uses. We examine a case in southeast Alaska to illustrate the breadth of these challenges and an approach to developing a science-based resource plan. Not only...
Social Risk Takers: Understanding Bilingualism in Mathematical Discussions
ERIC Educational Resources Information Center
Dominguez, Higinio
2017-01-01
The teaching and research communities in mathematics education agree that mathematical discussions pose challenges in elementary classrooms. These challenges continue to motivate research on mathematical discussions, with a focus on how students use talk in discussions. This study addresses the question, "What can teachers and researchers…
The challenges Concentrated Animal Feeding Operations (CAFOs) directly pose to sustainability include their impact on human health, receiving water bodies, groundwater, and air quality. These challenges result from the large quantities of macronutrients (carbon, nitrogen, and pho...
The Threat or Challenge of Accountability
ERIC Educational Resources Information Center
Rosenberg, Marvin L.; Brody, Ralph
1974-01-01
Social service agencies can improve accountability to their clients in specific ways. These techniques borrow some of the language and principles of management science and can be applied successfully only if social workers accept the challenge posed by accountability and view these concepts as compatible with professional values. (Author)
Exploration Design Challenge 2014
2014-04-25
Team Lore poses with NASA Administrator Charles Bolden and Lockheed Martin CEO, Marillyn Hewson. Team Lore was one of the semi-finalists in the Exploration Design Challenge. The goal of the Exploration Design Challenge is for students to research and design ways to protect astronauts from space radiation. The winner of the challenge was announced on April 25, 2014 at the USA Science and Engineering Festival at the Washington Convention Center in Washington, DC. Photo Credit: (NASA/Aubrey Gemignani)
Exploration Design Challenge 2014
2014-04-25
Team Aegis poses with NASA Administrator Charles Bolden and Lockheed Martin CEO, Marillyn Hewson. Team Aegis was one of the semi-finalists in the Exploration Design Challenge. The goal of the Exploration Design Challenge is for students to research and design ways to protect astronauts from space radiation. The winner of the challenge was announced on April 25, 2014 at the USA Science and Engineering Festival at the Washington Convention Center in Washington, DC. Photo Credit: (NASA/Aubrey Gemignani)
Berrue, Fabrice; Withers, Sydnor T; Haltli, Brad; Withers, Jo; Kerr, Russell G
2011-03-21
Marine invertebrates have proven to be a rich source of secondary metabolites. The growing recognition that marine microorganisms associated with invertebrate hosts are involved in the biosynthesis of secondary metabolites offers new alternatives for the discovery and development of marine natural products. However, the discovery of microorganisms producing secondary metabolites previously attributed to an invertebrate host poses a significant challenge. This study describes an efficient chemical screening method utilizing a 96-well plate-based bacterial cultivation strategy to identify and isolate microbial producers of marine invertebrate-associated metabolites.
Mathematical model for production of an industry focusing on worker status
NASA Astrophysics Data System (ADS)
Visalakshi, V.; kiran kumari, Sheshma
2018-04-01
Productivity improvement is posing a great challenge for industry everyday because of the difficulties in keeping track and priorising the variables that have significant impact on the productivity. The variation in production depends on the linguistic variables such as worker commitment, worker motivation and worker skills. Since the variables are linguistic we try to propose a model which gives an appropriate production of an industry. Fuzzy models aids the relationship between the factors and status. The model will support the industry to focus on the mentality of worker to increase the production.
Acquired pathology of the pediatric spine and spinal cord.
Palasis, Susan; Hayes, Laura L
2015-09-01
Pediatric spine pathology poses a diagnostic challenge for radiologists. Acquired spine pathology often yields nonspecific signs and symptoms in children, especially in the younger age groups, and diagnostic delay can carry significant morbidity. This review is focused on some of the more common diagnostic dilemmas we face when attempting to evaluate and diagnose acquired pediatric spine anomalies in daily practice. An understanding of some of the key differentiating features of these disease processes in conjunction with pertinent history, physical exam, and advanced imaging techniques can indicate the correct diagnosis.
Hoch, Jeffrey C
2017-10-01
Non-Fourier methods of spectrum analysis are gaining traction in NMR spectroscopy, driven by their utility for processing nonuniformly sampled data. These methods afford new opportunities for optimizing experiment time, resolution, and sensitivity of multidimensional NMR experiments, but they also pose significant challenges not encountered with the discrete Fourier transform. A brief history of non-Fourier methods in NMR serves to place different approaches in context. Non-Fourier methods reflect broader trends in the growing importance of computation in NMR, and offer insights for future software development. Copyright © 2017 Elsevier Inc. All rights reserved.
Femtosecond laser-assisted cataract surgery in pediatric patients.
Corredor-Ortega, Claudia; Gonzalez-Salinas, Roberto; Montero, María José; González-Flores, Rocío; Collura-Merlier, Allan; Cervantes-Coste, Guadalupe; Mendoza-Schuster, Erick; Velasco-Barona, Cecilio
2018-04-01
Pediatric cataract surgery poses a significant challenge for the cataract surgeon, in part because an elastic anterior capsule can make capsulorhexis difficult. With the use of femtosecond laser-assisted cataract surgery (FLACS), however, the continuous curvilinear capsulorhexis can be made with predictable size, circular shape, centration, and accuracy. In addition, topical anesthesia can be used for the FLACS docking procedure in cooperative children above 6 years of age, using transparent adhesive polyurethane film segments. Copyright © 2018 American Association for Pediatric Ophthalmology and Strabismus. Published by Elsevier Inc. All rights reserved.
Complex Nano-Scale Structures for Unprecedented Properties in Steels
Caballero, Francisca G.; Poplawsky, Jonathan D.; Yen, Hung Wei; ...
2016-11-01
Processing bulk nanoscrystalline materials for structural applications still poses a rather large challenge, particularly in achieving an industrially viable process. In this context, recent work has proved that complex nanoscale steel structures can be formed by solid reaction at low temperatures. These nanocrystalline bainitic steels present the highest strength ever recorded, unprecedented ductility, fatigue on par with commercial bearing steels and exceptional rolling-sliding wear performances. In this paper, a description of the characteristics and significance of these remarkable structures in the context of the atomic mechanism of transformation is provided.
Environment, Renewable Energy and Reduced Carbon Emissions
NASA Technical Reports Server (NTRS)
Sen, S.; Khazanov, G.; Kishimoto, Y.
2011-01-01
Increased energy security and reduced carbon emissions pose significant challenges for science and technology. However, they also create substantial opportunities for innovative research and development. In this review paper, we highlight some of the key opportunities and mention public policies that are needed to enable the efforts and to maximize the probability of their success. Climate is among the uttermost nonlinear behaviors found around us. As recent studies showed the possible effect of cosmic rays on the Earth's climate, we investigate how complex interactions between the planet and its environment can be responsible for climate anomalies.
Shah, Devendra H; Paul, Narayan C; Sischo, Willium C; Crespo, Rocio; Guard, Jean
2017-03-01
Salmonella spp. is the most predominant bacterial cause of foodborne gastroenteritis in humans. Due to the risk of human infection associated with poultry products and the prevalence of antimicrobial resistance, Salmonella also poses a significant challenge to commercial poultry production. During the last decade (2002 to 2012), the 12 most prevalent poultry-associated Salmonella serotypes (MPPSTs) were frequently and consistently isolated from poultry products in the United States. These MPPSTs and their percent prevalence in poultry products include Kentucky (4%), Enteritidis (2%) Heidelberg (2%), Typhimurium (2%), S. I 4,[5],12:i:- (0.31%), Montevideo (0.20%), Infantis (0.16%) Schwarzengrund (0.15%), Hadar (0.15%), Mbandaka (0.13%), Thompson (0.12%), and Senftenberg (0.04%). All MPPSTs except Kentucky are among the top 30 clinically significant serotypes that cause human illnesses in the United States. However with the exception of a few widely studied serotypes such as S. Enteritidis and Typhimurium, the ecology and epidemiology of the majority of MPPSTs still remain poorly investigated. Published data from the United States suggests that MPPSTs such as Heidelberg, Typhimurium, Kentucky, and Sentfenberg are more likely to be multi-drug resistant (MDR, ≥3 antimicobial classes) whereas Enteritidis, Montevideo, Schwarzengrund, Hadar, Infantis, Thompson, and Mbandaka are generally pan-susceptible or display resistance to fewer antimicobials. In contrast, the majority of MPPSTs isolated globally have been reported to display MDR phenotype. There also appears to be an international spread of a few MDR serotypes including Kentucky, Schwarzengrund, Hadar, Thomson, Sentfenberg, and Enteritidis, which may pose significant challenges to the public health. The current knowledge gaps on the ecology, epidemiology, and antimicrobial resistance of MPPSTs are discussed. © 2016 Poultry Science Association Inc.
Food Aversions and Cravings during Pregnancy on Yasawa Island, Fiji.
McKerracher, Luseadra; Collard, Mark; Henrich, Joseph
2016-09-01
Women often experience novel food aversions and cravings during pregnancy. These appetite changes have been hypothesized to work alongside cultural strategies as adaptive responses to the challenges posed by pregnancy (e.g., maternal immune suppression). Here, we report a study that assessed whether data from an indigenous population in Fiji are consistent with the predictions of this hypothesis. We found that aversions focus predominantly on foods expected to exacerbate the challenges of pregnancy. Cravings focus on foods that provide calories and micronutrients while posing few threats to mothers and fetuses. We also found that women who experience aversions to specific foods are more likely to crave foods that meet nutritional needs similar to those provided by the aversive foods. These findings are in line with the predictions of the hypothesis. This adds further weight to the argument that appetite changes may function in parallel with cultural mechanisms to solve pregnancy challenges.
Climate Change and Health in the Urban Context: The Experience of Barcelona.
Villalbí, Joan R; Ventayol, Irma
2016-07-01
Climate change poses huge challenges for public health, and cities are at the forefront of this process. The purpose of this paper is to present the issues climate change poses for public health in the city of Barcelona, how they are being addressed, and what are the current major challenges, trying to contribute to the development of a baseline understanding of the status of adaptation in cities from a public health perspective. The major issues related to climate change faced by the city are common to other urban centers in a Mediterranean climate: heat waves, water availability and quality, air quality, and diseases transmitted by vectors, and all are reviewed in detail with empirical data. They are not a potential threat for the future, but have actually challenged the city services and infrastructure over the last years, requiring sustainable responses and rigorous planning. © The Author(s) 2016.
Comparison of Student and Instructor Perceptions of Social Presence
ERIC Educational Resources Information Center
Mathieson, Kathleen; Leafman, Joan S.
2014-01-01
As enrollment in online courses continues to grow and online education is increasingly recognized as an established instructional mode, the unique challenges posed by this learning environment should be addressed. A primary challenge for virtual educators is developing social presence such that participants feel a sense of human connection with…
Prediction, Error, and Adaptation during Online Sentence Comprehension
ERIC Educational Resources Information Center
Fine, Alex Brabham
2013-01-01
A fundamental challenge for human cognition is perceiving and acting in a world in which the statistics that characterize available sensory data are non-stationary. This thesis focuses on this problem specifically in the domain of sentence comprehension, where linguistic variability poses computational challenges to the processes underlying…
Entrepreneurship Education Can Business Schools Meet the Challenge
ERIC Educational Resources Information Center
Kirby, David A.
2004-01-01
Examines the characteristics and role of the entrepreneur and the challenges for business schools posed by the need to develop more enterprising individuals. Argues that the traditional education system stultifies rather than develops the requisite attributes and skills to produce entrepreneurs, and proposes that if entrepreneurs are to be…
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…
Adoption of Internet2 in a Southwestern University: Human Resources Concerns
ERIC Educational Resources Information Center
Mendoza-Diaz, Noemi V.; Dooley, Larry M.; Dooley, Kim E.
2007-01-01
Human Resources are often times challenged by the integration of new technologies (Benson, Johnson, & Kichinke, 2002). Universities pose a unique challenge since they reluctantly adapt to changes (Torraco & Hoover, 2005; Watkins 2005). This is a dissertation study of the human resource concerns about adopting Internet2 in a…
A Perkins Challenge: Assessing Technical Skills in CTE
ERIC Educational Resources Information Center
Stone, James R., III
2009-01-01
Federal law requires state to develop performance measures and data-collection systems for secondary and postsecondary technical-skill attainment. This poses many challenges, such as defining a technical skills, measurement and when to assess students. In this article, the author outlines various assessment models and looks at the challenges…
Military Children and Families: Strengths and Challenges during Peace and War
ERIC Educational Resources Information Center
Park, Nansook
2011-01-01
Throughout history, military children and families have shown great capacity for adaptation and resilience. However, in recent years, unprecedented lengthy and multiple combat deployments of service members have posed multiple challenges for U.S. military children and families. Despite needs to better understand the impact of deployment on…
Intergenerational Challenges in Australian Jewish School Education
ERIC Educational Resources Information Center
Gross, Zehavit; Rutland, Suzanne D.
2014-01-01
The aim of this research is to investigate the intergenerational changes that have occurred in Australian Jewish day schools and the challenges these pose for religious and Jewish education. Using a grounded theory approach according to the constant comparative method (Strauss 1987), data from three sources (interviews [296], observations [27],…
USDA-ARS?s Scientific Manuscript database
The identification of host proteins that interact with virus proteins is a major challenge for the field of virology. Phloem-limited viruses pose extraordinary challenges for in vivo protein interaction experiments because these viruses are localized in very few and highly specialized host cells. ...
Evaluation Options for Family Resource Centers.
ERIC Educational Resources Information Center
Horsch, Karen, Ed.; Weiss, Heather B., Ed.
Family resource centers (FRC) are emerging as a promising program approach to solving urgent social problems. Evaluation plays an important role in learning how these programs work, what their impact is, and whether they should be expanded. However, FRCs pose unique challenges to evaluation. This report considers the challenges to evaluating FRCs,…
ERIC Educational Resources Information Center
Zilliox, Joseph T.; Lowery, Shannon G.
1997-01-01
Describes an extended investigation of polygons and polyhedra which was conducted in response to a challenge posed in Focus, a newsletter from the Mathematical Association of America (MAA). Students were challenged to construct a polyhedron with faces that measure more than 13 inches to a side. Outlines the process, including the questions posed…
ERIC Educational Resources Information Center
Yip, Virginia; Matthews, Stephen
2007-01-01
Findings from a longitudinal study of bilingual children acquiring Cantonese and English pose a challenge to the noun phrase accessibility hierarchy (NPAH; Keenan & Comrie, 1977), which predicts that object relatives should not be acquired before subject relatives. In the children's Cantonese, object relatives emerged earlier than or…
A Self-Adaptive Multi-Agent System Approach for Collaborative Mobile Learning
ERIC Educational Resources Information Center
de la Iglesia, Didac Gil; Calderon, Juan Felipe; Weyns, Danny; Milrad, Marcelo; Nussbaum, Miguel
2015-01-01
Mobile technologies have emerged as facilitators in the learning process, extending traditional classroom activities. However, engineering mobile learning applications for outdoor usage poses severe challenges. The requirements of these applications are challenging, as many different aspects need to be catered, such as resource access and sharing,…
Big Data Goes Personal: Privacy and Social Challenges
ERIC Educational Resources Information Center
Bonomi, Luca
2015-01-01
The Big Data phenomenon is posing new challenges in our modern society. In addition to requiring information systems to effectively manage high-dimensional and complex data, the privacy and social implications associated with the data collection, data analytics, and service requirements create new important research problems. First, the high…
Science, Sport and Technology--A Contribution to Educational Challenges
ERIC Educational Resources Information Center
O'Hara, Kelly; Reis, Paula; Esteves, Dulce; Bras, Rui; Branco, Luisa
2011-01-01
Improve students' ability to link knowledge with real life practice, through enhancing children or teenagers' ability to think critically by way of making observations, posing questions, drawing up hypotheses, planning and carrying out investigations, analysing data and therefore improve their decision making is an educational challenge. Learning…
Challenging Anti-Immigration Discourses in School and Community Contexts
ERIC Educational Resources Information Center
Allexsaht-Snider, Martha; Buxton, Cory A.; Harman, Ruth
2012-01-01
Rapid migration shifts, anti-immigrant discourses in the public sphere, and harsh immigration policies have posed daunting challenges for immigrant students, their families, their teachers, and their communities in the 21st century. Trends in public discourse and law enforcement in the United States mirror developments in European countries with…
Baldassarre, Gianluca; Santucci, Vieri Giuliano; Cartoni, Emilio; Caligiore, Daniele
2017-01-01
In this commentary, we highlight a crucial challenge posed by the proposal of Lake et al. to introduce key elements of human cognition into deep neural networks and future artificial-intelligence systems: the need to design effective sophisticated architectures. We propose that looking at the brain is an important means of facing this great challenge.
Iqbal, Corey W; Wall, James; Harrison, Michael R
2015-06-01
The incidence of pediatric disease conditions pales in comparison to adult disease. Consequently, many pediatric disorders are considered orphan diseases. Resources for the development of devices targeting orphan diseases are scarce and this poses a unique challenge to the development of pediatric devices. This article outlines these challenges and offers solutions. Copyright © 2015 Elsevier Inc. All rights reserved.
Thesis Writing Challenges for Non-Native MA Students
ERIC Educational Resources Information Center
Sadeghi, Karim; Shirzad Khajepasha, Arash
2015-01-01
Writing in a second (L2)/foreign language is generally a challenging activity, and writing an MA thesis, as an example of academic enterprise, can be daunting when done in a language in which the writer is not fully competent. The challenge such a genre of writing poses for L2 writers has not been properly addressed. To fill in the gap in this…
Comorbid Conditions in Neonates With Congenital Heart Disease.
Krishnamurthy, Ganga; Ratner, Veniamin; Bacha, Emile; Aspelund, Gudrun
2016-08-01
The objectives of this review are to discuss the pathophysiology, clinical impact and treatment of major noncardiac anomalies, and prematurity in infants with congenital heart disease. MEDLINE and PubMed. Mortality risk is significantly higher in patients with congenital heart disease and associated anomalies compared with those in whom the heart defect occurs in isolation. Although most noncardiac structural anomalies do not require surgery in the neonatal period, several require surgery for survival. Management of such infants poses multiple challenges. Premature infants with congenital heart disease face challenges imposed by their immature organ systems, which are susceptible to injury or altered function by congenital heart disease and abnormal circulatory physiology independent of congenital heart disease. For optimal outcomes in premature infants or in infants with multiple congenital anomalies, a collaborative interdisciplinary approach is necessary.
Getting educated: e-learning resources in the design and execution of surgical trials.
Bains, Simrit
2009-01-01
An evidence-based approach to research, which includes important aspects such as critical appraisal, is essential for the effective conduct of clinical trials. Researchers who are interested in educating themselves about its principles in order to incorporate them into their trials face challenges when attempting to acquire this information from traditional learning sources. E-learning resources offer an intriguing possibility of overcoming the challenges posed by traditional learning, and show promise as a way to expand accessibility to quality education about evidence-based principles. An assessment of existing e-learning resources reveals positive educational avenues for researchers, although significant flaws exist. The Global EducatorTM by Global Research Solutions addresses many of these flaws and is an e-learning resource that combines convenience with comprehensiveness.
International Myeloma Working Group recommendations for global myeloma care.
Ludwig, H; Miguel, J S; Dimopoulos, M A; Palumbo, A; Garcia Sanz, R; Powles, R; Lentzsch, S; Ming Chen, W; Hou, J; Jurczyszyn, A; Romeril, K; Hajek, R; Terpos, E; Shimizu, K; Joshua, D; Hungria, V; Rodriguez Morales, A; Ben-Yehuda, D; Sondergeld, P; Zamagni, E; Durie, B
2014-05-01
Recent developments have led to remarkable improvements in the assessment and treatment of patients with multiple myeloma (MM). New technologies have become available to precisely evaluate the biology and extent of the disease, including information about cytogenetics and genetic abnormalities, extramedullary manifestations and minimal residual disease. New, more effective drugs have been introduced into clinical practice, which enable clinicians to significantly improve the outcome of patients but also pose new challenges for the prevention and management of their specific side effects. Given these various new options and challenges, it is important to identify the minimal requirements for diagnosis and treatment of patients, as access to the most sophisticated advances may vary depending on local circumstances. Here, we propose the minimal requirements and possible options for diagnosis, monitoring and treatment of patients with multiple myeloma.
Soref, Erez
2007-01-01
This short article attempts to describe and review one of the most significant demographic phenomena in recent and upcoming decades namely the aging of the population, and discuss some of its implications for public health policies in Israel. The absolute and relative growth of the elderly proportion in the population poses a challenge in many respects, one aspect of which is in the field of mental health. The number one psychiatric problem in later life is late-life depression. Following a clinical and epidemiological review of late-life depression, a review of one specific treatment modality is presented - partial psychiatric hospitalization. This discussion is timely in light of the upcoming challenge of managed care in Israel's public mental health system.
Laser-based firing systems for prompt initiation of secondary explosives
NASA Technical Reports Server (NTRS)
Meeks, Kent D.; Setchell, Robert E.
1993-01-01
Motivated by issues of weapon safety and security, laser based firing systems for promptly initiating secondary explosives have been under active development at Sandia National Laboratories for more than four years. Such a firing system consists of miniaturized, Q-switched, solid-state laser, optical detonators, optical safety switches, and elements for splitting, coupling, and transmitting the laser output. Potential system applications pose significant challenges in terms of server mechanical and thermal environments and packaging constraints, while requiring clear demonstration of safety enhancements. The Direct Optical Initiation (DOI) Program at Sandia is addressing these challenges through progress development phases during which the design, fabrication, and testing of prototype hardware is aimed at more difficult application requirements. A brief history of the development program, and a summary of current and planned activities, will be presented.
Uncertainty Management in Remote Sensing of Climate Data. Summary of A Workshop
NASA Technical Reports Server (NTRS)
McConnell, M.; Weidman, S.
2009-01-01
Great advances have been made in our understanding of the climate system over the past few decades, and remotely sensed data have played a key role in supporting many of these advances. Improvements in satellites and in computational and data-handling techniques have yielded high quality, readily accessible data. However, rapid increases in data volume have also led to large and complex datasets that pose significant challenges in data analysis (NRC, 2007). Uncertainty characterization is needed for every satellite mission and scientists continue to be challenged by the need to reduce the uncertainty in remotely sensed climate records and projections. The approaches currently used to quantify the uncertainty in remotely sensed data, including statistical methods used to calibrate and validate satellite instruments, lack an overall mathematically based framework.
Exploration Design Challenge 2014
2014-04-25
Team Titan Shielding Systems poses with NASA Administrator Charles Bolden and Lockheed Martin CEO, Marillyn Hewson. Team Titan Shielding Systems was one of the semi-finalists in the Exploration Design Challenge. The goal of the Exploration Design Challenge is for students to research and design ways to protect astronauts from space radiation. The winner of the challenge was announced on April 25, 2014 at the USA Science and Engineering Festival at the Washington Convention Center in Washington, DC. Photo Credit: (NASA/Aubrey Gemignani)
Liu, Kai; Kokubo, Hironori
2017-10-23
Docking has become an indispensable approach in drug discovery research to predict the binding mode of a ligand. One great challenge in docking is to efficiently refine the correct pose from various putative docking poses through scoring functions. We recently examined the stability of self-docking poses under molecular dynamics (MD) simulations and showed that equilibrium MD simulations have some capability to discriminate between correct and decoy poses. Here, we have extended our previous work to cross-docking studies for practical applications. Three target proteins (thrombin, heat shock protein 90-alpha, and cyclin-dependent kinase 2) of pharmaceutical interest were selected. Three comparable poses (one correct pose and two decoys) for each ligand were then selected from the docking poses. To obtain the docking poses for the three target proteins, we used three different protocols, namely: normal docking, induced fit docking (IFD), and IFD against the homology model. Finally, five parallel MD equilibrium runs were performed on each pose for the statistical analysis. The results showed that the correct poses were generally more stable than the decoy poses under MD. The discrimination capability of MD depends on the strategy. The safest way was to judge a pose as being stable if any one run among five parallel runs was stable under MD. In this case, 95% of the correct poses were retained under MD, and about 25-44% of the decoys could be excluded by the simulations for all cases. On the other hand, if we judge a pose as being stable when any two or three runs were stable, with the risk of incorrectly excluding some correct poses, approximately 31-53% or 39-56% of the two decoys could be excluded by MD, respectively. Our results suggest that simple equilibrium simulations can serve as an effective filter to exclude decoy poses that cannot be distinguished by docking scores from the computationally expensive free-energy calculations.
DHS S&T First Responders Group and NATO Counter UAS Proposal Interest Response.
DOE Office of Scientific and Technical Information (OSTI.GOV)
Salton, Jonathan R.
The capability, speed, size, and widespread availability of small unmanned aerial systems (sUAS) makes them a serious security concern. The enabling technologies for sUAS are rapidly evolving and so too are the threats they pose to national security. Potential threat vehicles have a small cross-section, and are difficult to reliably detect using purely ground-based systems (e.g. radar or electro-optical) and challenging to target using conventional anti-aircraft defenses. Ground-based sensors are static and suffer from interference with the earth, vegetation and other man-made structures which obscure objects at low altitudes. Because of these challenges, sUAS pose a unique and rapidly evolvingmore » threat to national security.« less
An infant with chronic severe neutropenia
Bhat, Ramesh Y; Varma, Chaitanya P V; Bhatt, Sonia
2014-01-01
Neutropenia in infancy and childhood poses a diagnostic challenge as the aetiology ranges from acute life-threatening conditions to chronic benign diseases. Chronic benign neutropenia of infancy is a rare disorder occurring in 1:100 000. The neutrophil count continues to be low for a prolonged period until spontaneous resolution by the age of 3–4 years. Such infants are having higher incidences of minor infections requiring treatment with antibiotics and rare incidences of meningitis and sepsis. The authors describe an infant presenting with fever and cervical lymphadenitis, who was found to have isolated severe neutropenia and its persistence posing a diagnostic challenge. The prolonged course with minor infections and absence of serious underlying conditions finally confirmed chronic benign neutropenia of infancy. PMID:24711472
Wilson, Charlotte; Griffiths, Jane; Ewing, Gail; Connolly, Michael; Grande, Gunn
2014-01-01
In the United Kingdom, district nurses (DNs) support patients with advanced cancer in their homes. Although evidence suggests that DNs emphasize the distinctiveness of home rather than hospital settings, little is known about the specific challenges of delivering care in family-home settings. The objective of this study was to explore DNs' experiences of supporting patients within families. Focus groups were conducted with 40 DNs from 4 areas in the United Kingdom. The groups were digitally recorded and facilitated by researchers using a flexible topic guide. Verbatim transcripts were analyzed using thematic content analysis. Case-load complexity (household volatility) and family dynamics posed distinct challenges for nurses supporting patients. Many family members struggled with accepting the patients' prognosis and were complicit in withholding information. At times, this foreclosed a consideration of palliative options. Carers provide a great deal of positive supportive care within the home. However, for some, the home is characterized by conflict rather than consensus. Complexities surrounding family relationships pose a distinctive and challenging environment for DNs. Education and training of DNs should be designed to address the challenges of supporting patients within the family-home setting.
Dealing with femtorisks in international relations
Frank, Aaron Benjamin; Collins, Margaret Goud; Levin, Simon A.; Lo, Andrew W.; Ramo, Joshua; Dieckmann, Ulf; Kremenyuk, Victor; Kryazhimskiy, Arkady; Linnerooth-Bayer, JoAnne; Ramalingam, Ben; Roy, J. Stapleton; Saari, Donald G.; Thurner, Stefan; von Winterfeldt, Detlof
2014-01-01
The contemporary global community is increasingly interdependent and confronted with systemic risks posed by the actions and interactions of actors existing beneath the level of formal institutions, often operating outside effective governance structures. Frequently, these actors are human agents, such as rogue traders or aggressive financial innovators, terrorists, groups of dissidents, or unauthorized sources of sensitive or secret information about government or private sector activities. In other instances, influential “actors” take the form of climate change, communications technologies, or socioeconomic globalization. Although these individual forces may be small relative to state governments or international institutions, or may operate on long time scales, the changes they catalyze can pose significant challenges to the analysis and practice of international relations through the operation of complex feedbacks and interactions of individual agents and interconnected systems. We call these challenges “femtorisks,” and emphasize their importance for two reasons. First, in isolation, they may be inconsequential and semiautonomous; but when embedded in complex adaptive systems, characterized by individual agents able to change, learn from experience, and pursue their own agendas, the strategic interaction between actors can propel systems down paths of increasing, even global, instability. Second, because their influence stems from complex interactions at interfaces of multiple systems (e.g., social, financial, political, technological, ecological, etc.), femtorisks challenge standard approaches to risk assessment, as higher-order consequences cascade across the boundaries of socially constructed complex systems. We argue that new approaches to assessing and managing systemic risk in international relations are required, inspired by principles of evolutionary theory and development of resilient ecological systems. PMID:25404317
Tee, Augustine; Calzavacca, Paolo; Licari, Elisa; Goldsmith, Donna; Bellomo, Rinaldo
2008-01-01
Studies of hospital performance highlight the problem of 'failure to rescue' in acutely ill patients. This is a deficiency strongly associated with serious adverse events, cardiac arrest, or death. Rapid response systems (RRSs) and their efferent arm, the medical emergency team (MET), provide early specialist critical care to patients affected by the 'MET syndrome': unequivocal physiological instability or significant hospital staff concern for patients in a non-critical care environment. This intervention aims to prevent serious adverse events, cardiac arrests, and unexpected deaths. Though clinically logical and relatively simple, its adoption poses major challenges. Furthermore, research about the effectiveness of RRS is difficult to conduct. Sceptics argue that inadequate evidence exists to support its widespread application. Indeed, supportive evidence is based on before-and-after studies, observational investigations, and inductive reasoning. However, implementing a complex intervention like RRS poses enormous logistic, political, cultural, and financial challenges. In addition, double-blinded randomised controlled trials of RRS are simply not possible. Instead, as in the case of cardiac arrest and trauma teams, change in practice may be slow and progressive, even in the absence of level I evidence. It appears likely that the accumulation of evidence from different settings and situations, though methodologically imperfect, will increase the rationale and logic of RRS. A conclusive randomised controlled trial is unlikely to occur. All truth passes through three stages. First, it is ridiculed. Second, it is violently opposed. Third, it is accepted as being self-evident. Arthur Schopenhauer (1788–1860), German philosopher PMID:18254927
Dealing with femtorisks in international relations.
Frank, Aaron Benjamin; Collins, Margaret Goud; Levin, Simon A; Lo, Andrew W; Ramo, Joshua; Dieckmann, Ulf; Kremenyuk, Victor; Kryazhimskiy, Arkady; Linnerooth-Bayer, JoAnne; Ramalingam, Ben; Roy, J Stapleton; Saari, Donald G; Thurner, Stefan; von Winterfeldt, Detlof
2014-12-09
The contemporary global community is increasingly interdependent and confronted with systemic risks posed by the actions and interactions of actors existing beneath the level of formal institutions, often operating outside effective governance structures. Frequently, these actors are human agents, such as rogue traders or aggressive financial innovators, terrorists, groups of dissidents, or unauthorized sources of sensitive or secret information about government or private sector activities. In other instances, influential "actors" take the form of climate change, communications technologies, or socioeconomic globalization. Although these individual forces may be small relative to state governments or international institutions, or may operate on long time scales, the changes they catalyze can pose significant challenges to the analysis and practice of international relations through the operation of complex feedbacks and interactions of individual agents and interconnected systems. We call these challenges "femtorisks," and emphasize their importance for two reasons. First, in isolation, they may be inconsequential and semiautonomous; but when embedded in complex adaptive systems, characterized by individual agents able to change, learn from experience, and pursue their own agendas, the strategic interaction between actors can propel systems down paths of increasing, even global, instability. Second, because their influence stems from complex interactions at interfaces of multiple systems (e.g., social, financial, political, technological, ecological, etc.), femtorisks challenge standard approaches to risk assessment, as higher-order consequences cascade across the boundaries of socially constructed complex systems. We argue that new approaches to assessing and managing systemic risk in international relations are required, inspired by principles of evolutionary theory and development of resilient ecological systems.
Pose estimation of industrial objects towards robot operation
NASA Astrophysics Data System (ADS)
Niu, Jie; Zhou, Fuqiang; Tan, Haishu; Cao, Yu
2017-10-01
With the advantages of wide range, non-contact and high flexibility, the visual estimation technology of target pose has been widely applied in modern industry, robot guidance and other engineering practices. However, due to the influence of complicated industrial environment, outside interference factors, lack of object characteristics, restrictions of camera and other limitations, the visual estimation technology of target pose is still faced with many challenges. Focusing on the above problems, a pose estimation method of the industrial objects is developed based on 3D models of targets. By matching the extracted shape characteristics of objects with the priori 3D model database of targets, the method realizes the recognition of target. Thus a pose estimation of objects can be determined based on the monocular vision measuring model. The experimental results show that this method can be implemented to estimate the position of rigid objects based on poor images information, and provides guiding basis for the operation of the industrial robot.
Robust Head-Pose Estimation Based on Partially-Latent Mixture of Linear Regressions.
Drouard, Vincent; Horaud, Radu; Deleforge, Antoine; Ba, Sileye; Evangelidis, Georgios
2017-03-01
Head-pose estimation has many applications, such as social event analysis, human-robot and human-computer interaction, driving assistance, and so forth. Head-pose estimation is challenging, because it must cope with changing illumination conditions, variabilities in face orientation and in appearance, partial occlusions of facial landmarks, as well as bounding-box-to-face alignment errors. We propose to use a mixture of linear regressions with partially-latent output. This regression method learns to map high-dimensional feature vectors (extracted from bounding boxes of faces) onto the joint space of head-pose angles and bounding-box shifts, such that they are robustly predicted in the presence of unobservable phenomena. We describe in detail the mapping method that combines the merits of unsupervised manifold learning techniques and of mixtures of regressions. We validate our method with three publicly available data sets and we thoroughly benchmark four variants of the proposed algorithm with several state-of-the-art head-pose estimation methods.
3D ocular ultrasound using gaze tracking on the contralateral eye: a feasibility study.
Afsham, Narges; Najafi, Mohammad; Abolmaesumi, Purang; Rohling, Robert
2011-01-01
A gaze-deviated examination of the eye with a 2D ultrasound transducer is a common and informative ophthalmic test; however, the complex task of the pose estimation of the ultrasound images relative to the eye affects 3D interpretation. To tackle this challenge, a novel system for 3D image reconstruction based on gaze tracking of the contralateral eye has been proposed. The gaze fixates on several target points and, for each fixation, the pose of the examined eye is inferred from the gaze tracking. A single camera system has been developed for pose estimation combined with subject-specific parameter identification. The ultrasound images are then transformed to the coordinate system of the examined eye to create a 3D volume. Accuracy of the proposed gaze tracking system and the pose estimation of the eye have been validated in a set of experiments. Overall system error, including pose estimation and calibration, are 3.12 mm and 4.68 degrees.
NASA Astrophysics Data System (ADS)
Grudinin, Sergei; Kadukova, Maria; Eisenbarth, Andreas; Marillet, Simon; Cazals, Frédéric
2016-09-01
The 2015 D3R Grand Challenge provided an opportunity to test our new model for the binding free energy of small molecules, as well as to assess our protocol to predict binding poses for protein-ligand complexes. Our pose predictions were ranked 3-9 for the HSP90 dataset, depending on the assessment metric. For the MAP4K dataset the ranks are very dispersed and equal to 2-35, depending on the assessment metric, which does not provide any insight into the accuracy of the method. The main success of our pose prediction protocol was the re-scoring stage using the recently developed Convex-PL potential. We make a thorough analysis of our docking predictions made with AutoDock Vina and discuss the effect of the choice of rigid receptor templates, the number of flexible residues in the binding pocket, the binding pocket size, and the benefits of re-scoring. However, the main challenge was to predict experimentally determined binding affinities for two blind test sets. Our affinity prediction model consisted of two terms, a pairwise-additive enthalpy, and a non pairwise-additive entropy. We trained the free parameters of the model with a regularized regression using affinity and structural data from the PDBBind database. Our model performed very well on the training set, however, failed on the two test sets. We explain the drawback and pitfalls of our model, in particular in terms of relative coverage of the test set by the training set and missed dynamical properties from crystal structures, and discuss different routes to improve it.
Gravitational Wave Science: Challenges for Numerical Relativistic Astrophysics
NASA Technical Reports Server (NTRS)
Cenrella, Joan
2005-01-01
Gravitational wave detectors on earth and in space will open up a new observational window on the universe. The new information about astrophysics and fundamental physics these observations will bring is expected to pose exciting challenges. This talk will provide an overview of this emerging area of gravitational wave science, with a focus on the challenges it will bring for numerical relativistic astrophysics and a look at some recent results.
Exploration Design Challenge 2014
2014-04-25
Team ARES poses with NASA Administrator Charles Bolden and Lockheed Martin CEO, Marillyn Hewson. Team ARES was the winner of the Exploration Design Challenge. The goal of the Exploration Design Challenge is for students to research and design ways to protect astronauts from space radiation. The winning team was announced on April 25, 2014 at the USA Science and Engineering Festival at the Washington Convention Center in Washington, DC. Photo Credit: (NASA/Aubrey Gemignani)
Web-Scale Search-Based Data Extraction and Integration
2011-10-17
differently, posing challenges for aggregating this information. For example, for the task of finding population for cities in Benin, we were faced with...merged record. Our GeoMerging algorithm attempts to address various ambiguity challenges : • For name: The name of a hospital is not a unique...departments in the same building. For agent-extractor results from structured sources, our GeoMerging algorithm overcomes these challenges using a two
2011-09-28
e-Genius Aircraft Pilot Klaus Ohlmann poses for a photograph during the 2011 Green Flight Challenge, sponsored by Google, held at the Charles M. Schulz Sonoma County Airport in Santa Rosa, Calif. on Thursday, Sept. 29, 2011. NASA and the Comparative Aircraft Flight Efficiency (CAFE) Foundation are having the challenge with the goal to advance technologies in fuel efficiency and reduced emissions with cleaner renewable fuels and electric aircraft. Photo Credit: (NASA/Bill Ingalls)
2011-09-28
e-Genius Aircraft Pilot Eric Raymond poses for a photograph during the 2011 Green Flight Challenge, sponsored by Google, held at the Charles M. Schulz Sonoma County Airport in Santa Rosa, Calif. on Thursday, Sept. 29, 2011. NASA and the Comparative Aircraft Flight Efficiency (CAFE) Foundation are having the challenge with the goal to advance technologies in fuel efficiency and reduced emissions with cleaner renewable fuels and electric aircraft. Photo Credit: (NASA/Bill Ingalls)
2011-09-28
PhoEnix Aircraft Co-Pilot Jeff Shingleton poses for a photograph during the 2011 Green Flight Challenge, sponsored by Google, held at the Charles M. Schulz Sonoma County Airport in Santa Rosa, Calif. on Thursday, Sept. 29, 2011. NASA and the Comparative Aircraft Flight Efficiency (CAFE) Foundation are having the challenge with the goal to advance technologies in fuel efficiency and reduced emissions with cleaner renewable fuels and electric aircraft. Photo Credit: (NASA/Bill Ingalls)
2011-09-28
PhoEnix Aircraft Pilot Jim Lee poses for a photograph during the 2011 Green Flight Challenge, sponsored by Google, held at the Charles M. Schulz Sonoma County Airport in Santa Rosa, Calif. on Thursday, Sept. 29, 2011. NASA and the Comparative Aircraft Flight Efficiency (CAFE) Foundation are having the challenge with the goal to advance technologies in fuel efficiency and reduced emissions with cleaner renewable fuels and electric aircraft. Photo Credit: (NASA/Bill Ingalls)
2011-09-28
EcoEagle Aircraft Pilot Mikhael Ponso poses for a photograph during the 2011 Green Flight Challenge, sponsored by Google, held at the Charles M. Schulz Sonoma County Airport in Santa Rosa, Calif. on Thursday, Sept. 29, 2011. NASA and the Comparative Aircraft Flight Efficiency (CAFE) Foundation are having the challenge with the goal to advance technologies in fuel efficiency and reduced emissions with cleaner renewable fuels and electric aircraft. Photo Credit: (NASA/Bill Ingalls)
A Donor-Focused Fundraising Model: An Essential Tool in Community College Foundations' Toolkit
ERIC Educational Resources Information Center
Carter, Linnie S.
2011-01-01
The increased focus on private fundraising poses challenges for community colleges (Jackson & Glass, 2000). A challenge is a lack of fundraising experience within community colleges and their foundations. There now exists a donor-focused fundraising model for community colleges to use to enhance their fundraising initiatives and increase the…
"How Can I Help?": Practicing Familial Support through Simulation
ERIC Educational Resources Information Center
Coughlin, April B.; Dotger, Benjamin H.
2016-01-01
Teachers face numerous challenges in daily practice, including situations that involve the health, safety, and well-being of students and families. When harassment and physical abuse impact K-12 students, these situations pose unexpected challenges to novice teachers working to support their students. In this article, the authors report on a study…
A Strategy to Support Educational Leaders in Developing Countries to Manage Contextual Challenges
ERIC Educational Resources Information Center
Wolhuter, Charl; van der Walt, Hannes; Steyn, Hennie
2016-01-01
The central theoretical argument of this paper is that educational leadership and organisational development and change in educational institutions in developing countries will not be effective unless school leaders are aware of the challenges posed by contextual factors that might have an impact on their professional activities. The article…
Places to Go: Challenges to Multicultural Art Education in a Global Economy
ERIC Educational Resources Information Center
Desai, Dipti
2005-01-01
This article examines the relationship between globalization and postmodern multicultural art education. The questions that drive my investigation are: What is the role of postmodern multiculturalism in this current phase of globalization and what challenges does globalization pose for multiculturalism? I explore the shifts in the field of art…
A Systematic Approach to Faculty Development--Capability Improvement for Blended Learning
ERIC Educational Resources Information Center
Badawood, Ashraf; Steenkamp, Annette Lerine; Al-Werfalli, Daw
2013-01-01
Blended learning (BL) provides an efficient and effective instructional experience. However, adopting a BL approach poses some challenges to faculty; the most important obstacle found in this research is faculty's lack of knowledge regarding the use of technology in their teaching. This challenge prompted the research project focused on improving…
Governing during an Institutional Crisis: 10 Fundamental Principles
ERIC Educational Resources Information Center
White, Lawrence
2012-01-01
In today's world, managing a campus crisis poses special challenges for an institution's governing board, which may operate some distance removed from the immediate events giving rise to the crisis. In its most challenging form, a campus crisis--a shooting, a natural disaster, a fraternity hazing death, the arrest of a prominent campus…
Teaching Caribbean Students: Research on Social Issues in the Caribbean and Abroad.
ERIC Educational Resources Information Center
Bastick, Tony, Ed.; Ezenne, Austin, Ed.
The issues and findings in the research essays in this collection focus on two main themes: the identification of challenges in preparing Caribbean students for the new global network and the isolation of the challenges posed in developing these global relations. Part 1, "Socially Sensitive Pedagogies," contains: (1) "Domain-Specific Modern…
Using Testimonial Response to Frame the Challenges and Possibilities of Risky Historical Texts
ERIC Educational Resources Information Center
Damico, James; Apol, Laura
2008-01-01
Literature that vividly and explicitly describes (often in the form of testimonies from one or more characters) traumatic and/or catastrophic events of human history poses particular challenges for readers. This article proposes testimonial response as one approach to responding to these "risky historical texts." By way of introducing "testimonial…
Using Facebook to Engage Learners in a Large Introductory Course
ERIC Educational Resources Information Center
Dougherty, Kevin D.; Andercheck, Brita
2014-01-01
Classes of hundreds pose special challenges for teaching and learning. Notable among these challenges is the tendency for students to feel like anonymous spectators rather than active, collaborative participants. To combat this tendency, we used the popular social networking site Facebook to cultivate a sense of community among 200-plus students…
Using System Dynamics as an Evaluation Tool: Experience from a Demonstration Program
ERIC Educational Resources Information Center
Fredericks, Kimberly A.; Deegan, Michael; Carman, Joanne G.
2008-01-01
Evaluators are often faced with many challenges in the design and implementation of a program's evaluation. Because programs are entangled in complex networks of structures and stakeholders, they can be challenging to understand, and they often pose issues of competing and conflicting goals. However, by using a systems mapping approach to…
The Dynamics of Multicultural NPD Teams in Virtual Environments
ERIC Educational Resources Information Center
Fain, Nusa; Kline, Miro
2013-01-01
Changes in the business environment, responses of companies to these changes and the available information and communication technologies (ICT) pose a number of challenges to present and future product developers, as well as to educational institutions. An appropriate response to these challenges is to create a solid basis for strategies to combat…
DOT National Transportation Integrated Search
2016-03-11
The purpose of this work is to identify instances where the existing Federal Motor Vehicle Safety Standards may pose challenges to the introduction of automated vehicles. It identifies standards requiring further review - both to ensure that existing...
Managing Welfare Reform in Five States: The Challenge of Devolution.
ERIC Educational Resources Information Center
Liebschutz, Sarah F., Ed.
This book analyzes the responses of five states (Florida, Mississippi, New York, Washington, and Wisconsin) to challenges posed by the Personal Responsibility and Work Opportunity Reconciliation Act of 1996 to alter state welfare programs and management systems. Using case studies, the book highlights similarities and differences in the states'…
Reading Desire: From Empathy to Estrangement, from Enlightenment to Implication
ERIC Educational Resources Information Center
Taylor, Lisa K.
2007-01-01
The imperial hubris, insecurities and indifference of our bloody new millennium pose profound challenges to feminist anti-racist and anti-colonial educators. For those of us who turn to literature education to create spaces of sustained moral reflection, there is a particular challenge to think through the kinds of reading practices which might…
Responding to the Mental Health and Well-Being Agenda in Adult Community Learning
ERIC Educational Resources Information Center
Lewis, Lydia
2014-01-01
In the United Kingdom, changes in the policy, funding and commissioning landscape for mental health and well-being are posing opportunities and challenges for adult community learning (ACL). Opportunities include increased recognition of, and funding for, the "wider benefits" of learning, whereas challenges include the risks of ACL…
Automating a Massive Online Course with Cluster Computing
ERIC Educational Resources Information Center
Haas, Timothy C.
2016-01-01
Before massive numbers of students can take online courses for college credit, the challenges of providing tutoring support, answers to student-posed questions, and the control of cheating will need to be addressed. These challenges are taken up here by developing an online course delivery system that runs in a cluster computing environment and is…
Ethical Challenges of In-The-Field Training: A Surgical Perspective
ERIC Educational Resources Information Center
Bernstein, Mark; Knifed, Eva
2007-01-01
The teaching of professions in which technical and manual acts combined with excellent judgment are used to enhance the safety of people, poses challenges to educators. Book learning combined with mock or simulated situations goes a long way, but ultimately "in-the-field" instruction and learning is necessary to qualify trainees for many…
ERIC Educational Resources Information Center
Smit, Renee
2012-01-01
The increased diversity in the student body resulting from massification poses particular challenges to higher education. This article engages the uncritical use of the "disadvantage" discourse and its effect on pedagogy. It explores some of the challenges of coping with student diversity, with particular reference to the South African…
ERIC Educational Resources Information Center
Langrehr, Don
2003-01-01
Outlines a study in which television advertising supplied the text that college students were challenged to interpret. Explains that the language and images of this advertising posed a complex, cognitive challenge--even to these students at advanced levels of education. Concludes that information processing of television advertising presents a…
Challenges to Common Core State Standards Implementation: Views from Six States
ERIC Educational Resources Information Center
Smith, Joanna; Thier, Michael
2017-01-01
The implementation of the Common Core State Standards has posed a number of challenges for school leaders. This study applies a policy implementation conceptual framework to analyze data gathered from 46 interviews in six states. Findings suggest the existence of multiple barriers to Common Core State Standards implementation. To promote…
The path for incorporating new alternative methods and technologies into quantitative chemical risk assessment poses a diverse set of scientific challenges. Some of these challenges include development of relevant and predictive test systems and computational models to integrate...
Autonomy in Second Language Phonology: Choice vs. Limits
ERIC Educational Resources Information Center
Moyer, Alene
2017-01-01
Learning a new sound system poses challenges of a social, psychological, and cognitive nature, but the learner's decisions are key to ultimate attainment. This presentation focuses on two essential concepts: CHOICE, or how one wants to sound in the target language; and LIMITS, or various challenges to one's goals vis-a-vis accent. Qualitative and…
Business Process Reengineering towards an Integrated Learning Management System
ERIC Educational Resources Information Center
Basal, Abdelraheem Mousa
2010-01-01
The task of managing an information technology (IT) system in a school environment poses unique challenges. For example, one of the greatest challenges facing individual schools is the lack of integration among various information systems. The present situation in many schools is that there are many disconnected systems managing many different…
The Challenge of the Community College to the Church.
ERIC Educational Resources Information Center
Hallman, W. E., Ed.
The ten essays presented in this collection address various aspects of the relationship of the church and the community college. In the first two essays, C. Freeman Sleeper examines the challenges posed by community colleges to the church's traditional support of higher education and, then, discusses approaches to addressing the moral issues…
Artists, Creativity and Knowledge: A Challenge for Doctoral Change
ERIC Educational Resources Information Center
Phillips, Maggi
2009-01-01
This paper aims to extrapolate the difficulties and challenges posed by ideas about creativity principally in the context of doctoral theses in which the practices of dance play a prominent, if not, pivotal role. While resisting definitive transparency, creativity is a crucial marker as much for postgraduate scholars as it is for artists. The…
Captions and Reduced Forms Instruction: The Impact on EFL Students' Listening Comprehension
ERIC Educational Resources Information Center
Yang, Jie Chi; Chang, Peichin
2014-01-01
For many EFL learners, listening poses a grave challenge. The difficulty in segmenting a stream of speech and limited capacity in short-term memory are common weaknesses for language learners. Specifically, reduced forms, which frequently appear in authentic informal conversations, compound the challenges in listening comprehension. Numerous…
Plate Tectonics: A Paradigm under Threat.
ERIC Educational Resources Information Center
Pratt, David
2000-01-01
Discusses the challenges confronting plate tectonics. Presents evidence that contradicts continental drift, seafloor spreading, and subduction. Reviews problems posed by vertical tectonic movements. (Contains 242 references.) (DDR)
Preliminary Recommendations for the Collection, Storage, and Analysis of UAS Safety Data
NASA Technical Reports Server (NTRS)
Enomoto, Francis; Bushnell, David; Denney, Ewen; Pai, Ganesh; Schumann, Johann
2013-01-01
Although the use of UASs in military and public service operations is proliferating, civilian use of UASs remains limited in the United States today. With efforts underway to accommodate and integrate UASs into the NAS, a proactive understanding of safety issues, i.e., the unique hazards and the corresponding risks that UASs pose not only through their operations for commercial purposes, but also to existing operations in the NAS, is especially important so as to (a) support the development of a sound regulatory basis, (b) regulate, design and properly equip UASs, and (c) effectively mitigate the risks posed. Data, especially about system and component failures, incidents, and accidents, provides valuable insight into how performance and operational capabilities/limitations contribute to hazards. Since the majority of UAS operations today take place in a context that is significantly different from the norm in civil aviation, i.e., with different operational goals and standards, identifying that which constitutes useful and sufficient data on UASs and their operations is a substantial research challenge.
Body Parts Dependent Joint Regressors for Human Pose Estimation in Still Images.
Dantone, Matthias; Gall, Juergen; Leistner, Christian; Van Gool, Luc
2014-11-01
In this work, we address the problem of estimating 2d human pose from still images. Articulated body pose estimation is challenging due to the large variation in body poses and appearances of the different body parts. Recent methods that rely on the pictorial structure framework have shown to be very successful in solving this task. They model the body part appearances using discriminatively trained, independent part templates and the spatial relations of the body parts using a tree model. Within such a framework, we address the problem of obtaining better part templates which are able to handle a very high variation in appearance. To this end, we introduce parts dependent body joint regressors which are random forests that operate over two layers. While the first layer acts as an independent body part classifier, the second layer takes the estimated class distributions of the first one into account and is thereby able to predict joint locations by modeling the interdependence and co-occurrence of the parts. This helps to overcome typical ambiguities of tree structures, such as self-similarities of legs and arms. In addition, we introduce a novel data set termed FashionPose that contains over 7,000 images with a challenging variation of body part appearances due to a large variation of dressing styles. In the experiments, we demonstrate that the proposed parts dependent joint regressors outperform independent classifiers or regressors. The method also performs better or similar to the state-of-the-art in terms of accuracy, while running with a couple of frames per second.
Sinha, Samir K
2011-01-01
Canada's aging population poses a significant challenge for the existing healthcare system. While individuals 65 and older accounted for 13.7% of the population in 2005, they accounted for 60% of all acute care service spending. This paper further illustrates how the heterogeneity of the older population and its impact on patterns of healthcare use demonstrate the failings of our current care systems. Our outdated acute care models frequently disadvantage the system's highest users, who are often characterized by factors such as poly-morbidity, functional impairment and social frailty. Understanding how implementing innovative models that challenge deeply ingrained ways of providing care has proven to be a significant challenge, this paper highlights one hospital's mission to transform current traditional paradigms of care by developing and implementing an elder-friendly hospital integrated service delivery model. This hospital aims to demonstrate wide-ranging benefits of this model that can contribute toward optimizing the outcomes of hospitalization for older adults and the system as a whole. The establishment of a national agency that could support the development of a national aging strategy to promote best practice dissemination and implementation could also ensure that the significant health, social and economic benefits that better care models can realize could be more easily achieved.
NASA Astrophysics Data System (ADS)
Lall, U.; Allaire, M.; Ceccato, P.; Haraguchi, M.; Cian, F.; Bavandi, A.
2017-12-01
Catastrophic floods can pose a significant challenge for response and recovery. A key bottleneck in the speed of response is the availability of funds to a country or regions finance ministry to mobilize resources. Parametric instruments, where the release of funs is tied to the exceedance of a specified index or threshold, rather than to loss verification are well suited for this purpose. However, designing and appropriate index, that is not subject to manipulation and accurately reflects the need is a challenge, especially in developing countries which have short hydroclimatic and loss records, and where rapid land use change has led to significant changes in exposure and hydrology over time. The use of long records of rainfall from climate re-analyses, flooded area and land use from remote sensing to design and benchmark a parametric index considering the uncertainty and representativeness of potential loss is explored with applications to Bangladesh and Thailand. Prospects for broader applicability and limitations are discussed.
Observations of Shock Diffusion and Interactions in Supersonic Freestreams with Counterflowing Jets
NASA Technical Reports Server (NTRS)
Daso, Endwell O.; Pritchett, Victor E.; Wang, Ten-See; Blankson, Isiah M.; Auslender, Aaron H.
2006-01-01
One of the technical challenges in long-duration space exploration and interplanetary missions is controlled entry and re-entry into planetary and Earth atmospheres, which requires the dissipation of considerable kinetic energy as the spacecraft decelerates and penetrates the atmosphere. Efficient heat load management of stagnation points and acreage heating remains a technological challenge and poses significant risk, particularly for human missions. An innovative approach using active flow control concept is proposed to significantly modify the external flow field about the spacecraft in planetary atmospheric entry and re-entry in order to mitigate the harsh aerothermal environments, and significantly weaken and disperse the shock-wave system to reduce aerothermal loads and wave drag, as well as improving aerodynamic performance. To explore the potential benefits of this approach, we conducted fundamental experiments in a trisonic blow down wind tunnel to investigate the effects of counterflowing sonic and supersonic jets against supersonic freestreams to gain a better understanding of the flow physics of the interactions of the opposing flows and the resulting shock structure.
3D face recognition under expressions, occlusions, and pose variations.
Drira, Hassen; Ben Amor, Boulbaba; Srivastava, Anuj; Daoudi, Mohamed; Slama, Rim
2013-09-01
We propose a novel geometric framework for analyzing 3D faces, with the specific goals of comparing, matching, and averaging their shapes. Here we represent facial surfaces by radial curves emanating from the nose tips and use elastic shape analysis of these curves to develop a Riemannian framework for analyzing shapes of full facial surfaces. This representation, along with the elastic Riemannian metric, seems natural for measuring facial deformations and is robust to challenges such as large facial expressions (especially those with open mouths), large pose variations, missing parts, and partial occlusions due to glasses, hair, and so on. This framework is shown to be promising from both--empirical and theoretical--perspectives. In terms of the empirical evaluation, our results match or improve upon the state-of-the-art methods on three prominent databases: FRGCv2, GavabDB, and Bosphorus, each posing a different type of challenge. From a theoretical perspective, this framework allows for formal statistical inferences, such as the estimation of missing facial parts using PCA on tangent spaces and computing average shapes.
University Students' Problem Posing Abilities and Attitudes towards Mathematics.
ERIC Educational Resources Information Center
Grundmeier, Todd A.
2002-01-01
Explores the problem posing abilities and attitudes towards mathematics of students in a university pre-calculus class and a university mathematical proof class. Reports a significant difference in numeric posing versus non-numeric posing ability in both classes. (Author/MM)
New challenges for text mining: mapping between text and manually curated pathways
Oda, Kanae; Kim, Jin-Dong; Ohta, Tomoko; Okanohara, Daisuke; Matsuzaki, Takuya; Tateisi, Yuka; Tsujii, Jun'ichi
2008-01-01
Background Associating literature with pathways poses new challenges to the Text Mining (TM) community. There are three main challenges to this task: (1) the identification of the mapping position of a specific entity or reaction in a given pathway, (2) the recognition of the causal relationships among multiple reactions, and (3) the formulation and implementation of required inferences based on biological domain knowledge. Results To address these challenges, we constructed new resources to link the text with a model pathway; they are: the GENIA pathway corpus with event annotation and NF-kB pathway. Through their detailed analysis, we address the untapped resource, ‘bio-inference,’ as well as the differences between text and pathway representation. Here, we show the precise comparisons of their representations and the nine classes of ‘bio-inference’ schemes observed in the pathway corpus. Conclusions We believe that the creation of such rich resources and their detailed analysis is the significant first step for accelerating the research of the automatic construction of pathway from text. PMID:18426550
Communicating about smoke from wildland fire: challenges and opportunities for managers.
Olsen, Christine S; Mazzotta, Danielle K; Toman, Eric; Fischer, A Paige
2014-09-01
Wildland fire and associated management efforts are dominant topics in natural resource fields. Smoke from fires can be a nuisance and pose serious health risks and aggravate pre-existing health conditions. When it results in reduced visibility near roadways, smoke can also pose hazardous driving conditions and reduce the scenic value of vistas. Communicating about smoke, whether in the preparation phases before a planned burn or during a wildfire event, can enable those at risk to make informed decisions to minimize their exposure to smoke or choose alternate activities that mitigate smoke completely. To date, very little research has been completed on the social aspects of smoke, such as communication or public perceptions. Here, we present findings from an exploratory study that examined challenges and opportunities related to communication (within agencies or to the public) for management of smoke from wildland fires. Interviews were conducted in California, Oregon, Montana, and South Carolina among a purposive sample of individuals, who are involved in fire or smoke management. Findings indicate that smoke poses several challenges to management agencies. Findings also provide insight into potential strategies to address such challenges by improving communication in both inter- and intra-agency situations as well as with members of the public. In particular, prioritizing fire and smoke-related communication within agencies, allocating agency resources specifically for training in communication and outreach endeavors, taking advantage of existing resources including informal social networks among the public, and building long-term relationships both between agencies and with the public were viewed as effective.
DOE Office of Scientific and Technical Information (OSTI.GOV)
Ramuhalli, Pradeep; Hirt, Evelyn H.; Pitman, Stan G.
The harsh environments in advanced reactors (AdvRx) increase the possibility of degradation of safety-critical passive components, and therefore pose a particular challenge for deployment and extended operation of these concepts. Nondestructive evaluation technologies are an essential element for obtaining information on passive component condition in AdvRx, with the development of sensor technologies for nondestructively inspecting AdvRx passive components identified as a key need. Given the challenges posed by AdvRx environments and the potential needs for reducing the burden posed by periodic in-service inspection of hard-to-access and hard-to-replace components, a viable solution may be provided by online condition monitoring of components.more » This report identifies the key challenges that will need to be overcome for sensor development in this context, and documents an experimental plan for sensor development, test, and evaluation. The focus of initial research and development is on sodium fast reactors, with the eventual goal of the research being developing the necessary sensor technology, quantifying sensor survivability and long-term measurement reliability for nondestructively inspecting critical components. Materials for sensor development that are likely to withstand the harsh environments are described, along with a status on the fabrication of reference specimens, and the planned approach for design and evaluation of the sensor and measurement technology.« less
Laser Remediation of Threats Posed by Small Orbital Debris
NASA Technical Reports Server (NTRS)
Fork, Richard L.; Rogers, Jan R.; Hovater, Mary A.
2012-01-01
The continually increasing amount of orbital debris in near Earth space poses an increasing challenge to space situational awareness. Recent collisions of spacecraft caused abrupt increases in the density of both large and small debris in near Earth space. An especially challenging class of threats is that due to the increasing density of small (1 mm to 10 cm dimension) orbital debris. This small debris poses a serious threat since: (1) The high velocity enables even millimeter dimension debris to cause serious damage to vulnerable areas of space assets, e.g., detector windows; (2) The small size and large number of debris elements prevent adequate detection and cataloguing. We have identified solutions to this threat in the form of novel laser systems and novel ways of using these laser systems. While implementation of the solutions we identify is challenging we find approaches offering threat mitigation within time frames and at costs of practical interest. We base our analysis on the unique combination of coherent light specifically structured in both space and time and applied in novel ways entirely within the vacuum of space to deorbiting small debris. We compare and contrast laser based small debris removal strategies using ground based laser systems with strategies using space based laser systems. We find laser systems located and used entirely within space offer essential and decisive advantages over groundbased laser systems.
Mickey Mouse poses with a portrait of Ronald McNair
NASA Technical Reports Server (NTRS)
1999-01-01
In the gymnasium of Ronald McNair Magnet School in Cocoa, Fla., Mickey Mouse poses with a portrait of NASA astronaut Ronald McNair. The portrait was presented to the school by Walt Disney World during a tribute to McNair. The school had previously been renamed for the fallen astronaut who was one of a crew of seven who lost their lives during an accident following launch of the Space Shuttle Challenger in January 1986.
Postinflammatory hyperpigmentation in patients with skin of color.
Shokeen, Divya
2016-01-01
Postinflammatory hyperpigmentation (PIH) has posed a substantial challenge for patients with higher Fitzpatrick skin types, specifically types III to VI. Treatment modalities pose a number of limitations due to the number of treatments required, potential side effects, and overall efficacy. Fortunately, multiple therapies have been delineated that can be moderately to highly efficacious in treating PIH in patients with skin of color. This article will review some of these modalities and procedures for this common patient concern.
Salvage of locally recurrent prostate cancer after definitive radiotherapy.
Mendenhall, William M; Henderson, Randal H; Hoppe, Bradford S; Nichols, Romaine C; Mendenhall, Nancy P
2014-08-01
Although a significant proportion of patients with localized prostate cancer are cured after definitive radiotherapy, solitary local recurrence is observed in a subset of patients and poses a management challenge. Curative-intent treatment options include prostatectomy, reirradiation, cryotherapy, and high-intensity-focused ultrasound. Outcomes data after any of these options are relatively limited. The 5-year biochemical progression-free survival rate is approximately 50% after salvage prostatectomy. However, the morbidity rate of the procedure is significantly higher compared with that observed in previously untreated patients. The likelihood of cure after low dose rate brachytherapy is similar to that observed after salvage prostatectomy, and the morbidity, although significant is less. Although cryotherapy and high-intensity-focused ultrasound may be less morbid than a prostatectomy, the probability of cure is probably lower.
Halikiopoulou, Daphne
2017-07-11
Speed and Mannion make a good case that the rise of populism poses significant challenges for health policy. This commentary suggests that the link between populism and health policy should be further nuanced in four ways. First, a deconstruction of the term populism itself and a focus on the far right dimension of populist politics; second, a focus on the supply side and more specifically the question of nationalism and the 'national preference'; third, the dynamics of party competition during economic crisis; and fourth the question of policy, and more specifically the extent to which certain labour market policies are able to mediate demand for the far right. © 2018 The Author(s); Published by Kerman University of Medical Sciences. This is an open-access article distributed under the terms of the Creative Commons Attribution License (http://creativecommons.org/licenses/by/4.0), which permits unrestricted use, distribution, and reproduction in any medium, provided the original work is properly cited.
NASA Astrophysics Data System (ADS)
Ahmad, Kashif; Conci, Nicola; Boato, Giulia; De Natale, Francesco G. B.
2017-11-01
Over the last few years, a rapid growth has been witnessed in the number of digital photos produced per year. This rapid process poses challenges in the organization and management of multimedia collections, and one viable solution consists of arranging the media on the basis of the underlying events. However, album-level annotation and the presence of irrelevant pictures in photo collections make event-based organization of personal photo albums a more challenging task. To tackle these challenges, in contrast to conventional approaches relying on supervised learning, we propose a pipeline for event recognition in personal photo collections relying on a multiple instance-learning (MIL) strategy. MIL is a modified form of supervised learning and fits well for such applications with weakly labeled data. The experimental evaluation of the proposed approach is carried out on two large-scale datasets including a self-collected and a benchmark dataset. On both, our approach significantly outperforms the existing state-of-the-art.
Thakur, Sveta; Singh, Lakhveer; Wahid, Zularisam Ab; Siddiqui, Muhammad Faisal; Atnaw, Samson Mekbib; Din, Mohd Fadhil Md
2016-04-01
Increasing heavy metal (HM) concentrations in the soil have become a significant problem in the modern industrialized world due to several anthropogenic activities. Heavy metals (HMs) are non-biodegradable and have long biological half lives; thus, once entered in food chain, their concentrations keep on increasing through biomagnification. The increased concentrations of heavy metals ultimately pose threat on human life also. The one captivating solution for this problem is to use green plants for HM removal from soil and render it harmless and reusable. Although this green technology called phytoremediation has many advantages over conventional methods of HM removal from soils, there are also many challenges that need to be addressed before making this technique practically feasible and useful on a large scale. In this review, we discuss the mechanisms of HM uptake, transport, and plant tolerance mechanisms to cope with increased HM concentrations. This review article also comprehensively discusses the advantages, major challenges, and future perspectives of phytoremediation of heavy metals from the soil.
Advanced consequence management program: challenges and recent real-world implementations
NASA Astrophysics Data System (ADS)
Graser, Tom; Barber, K. S.; Williams, Bob; Saghir, Feras; Henry, Kurt A.
2002-08-01
The Enhanced Consequence Management, Planning and Support System (ENCOMPASS) was developed under DARPA's Advanced Consequence Management program to assist decision-makers operating in crisis situations such as terrorist attacks using conventional and unconventional weapons and natural disasters. ENCOMPASS provides the tools for first responders, incident commanders, and officials at all levels to share vital information and consequently, plan and execute a coordinated response to incidents of varying complexity and size. ENCOMPASS offers custom configuration of components with capabilities ranging from map-based situation assessment, situation-based response checklists, casualty tracking, and epidemiological surveillance. Developing and deploying such a comprehensive system posed significant challenges for DARPA program management, due to an inherently complex domain, a broad spectrum of customer sites and skill sets, an often inhospitable runtime environment, demanding development-to-deployment transition requirements, and a technically diverse and geographically distributed development team. This paper introduces ENCOMPASS and explores these challenges, followed by an outline of selected ENCOMPASS deployments, demonstrating how ENCOMPASS can enhance consequence management in a variety real world contexts.
Miller, Karl; Turró, R; Greve, J W; Bakker, C M; Buchwald, J N; Espinós, J C
2017-02-01
Pose SM is an endolumenal weight-loss intervention in which suture anchors are placed endoscopically in the gastric fundus/distal gastric body. Observational studies of pose have shown safe, effective weight loss. Twelve-month results of a randomized controlled trial comparing weight loss and satiety after pose vs. conventional medical therapy are reported. Subjects with classes I-II obesity were randomized in a 3:1 ratio to pose or diet/exercise guidance only (control). Pose subjects received gastric fundus and distal body suture-anchor plications with diet/exercise counseling. Total body (%TBWL) and excess weight loss (%EWL) were assessed at 6 and 12 months. Analysis of covariance (ANCOVA) was used to analyze 12-month %TBWL. Satiety changes were assessed at 6 and 12 months. From November 2013 to July 2014, 44 subjects were randomized (34, 77.3 % female; mean age, 38.3 ± 10.7 years; body mass index, 36.5 ± 3.4 kg/m 2 ) to pose (n = 34) or control (n = 10) groups in three centers. Mean pose procedure time was 51.8 ± 14.5 min; pose subjects received a mean 8.8 ± 1.3 fundal and 4.2 ± 0.7 distal body plications. Twelve-month TBWL: pose, 13.0 % (EWL, 45.0 %), n = 30 vs. control group, 5.3 % (18.1 %), n = 9; significant mean difference, 7.7 % (95 % CI 2.2, 13.2; p < 0.01). Pose subjects showed significant reductions in satiety parameters (p < 0.001); controls experienced reduced caloric intake and satiety volume (p < 0.05). No serious device- or procedure-related adverse events occurred. In a randomized controlled trial at 12 months, pose-treated subjects had significantly greater weight loss than those treated with diet/exercise guidance alone. At 6 and 12 months, pose subjects showed significant reduction in satiety parameters. clinicaltrials.gov identifier # NCT01843231.
Heating and current drive on NSTX
NASA Astrophysics Data System (ADS)
Wilson, J. R.; Batchelor, D.; Carter, M.; Hosea, J.; Ignat, D.; LeBlanc, B.; Majeski, R.; Ono, M.; Phillips, C. K.; Rogers, J. H.; Schilling, G.
1997-04-01
Low aspect ratio tokamaks pose interesting new challenges for heating and current drive. The NSTX (National Spherical Tokamak Experiment) device to be built at Princeton is a low aspect ratio toroidal device that has the achievement of high toroidal beta (˜45%) and non-inductive operation as two of its main research goals. To achieve these goals significant auxiliary heating and current drive systems are required. Present plans include ECH (Electron cyclotron heating) for pre-ionization and start-up assist, HHFW (high harmonic fast wave) for heating and current drive and eventually NBI (neutral beam injection) for heating, current drive and plasma rotation.
Cardiopulmonary bypass with bivalirudin in type II heparin-induced thrombocytopenia.
Clayton, Stephanie B; Acsell, Jeffrey R; Crumbley, Arthur J; Uber, Walter E
2004-12-01
Cardiopulmonary bypass in patients with type II heparin induced-thrombocytopenia poses significant challenges. Inadequate pharmacokinetic profiles, monitoring, reversibility, and availability often limit alternative anticoagulation strategies. Bivalirudin, a semisynthetic direct thrombin inhibitor, was recently approved for use in patients undergoing percutaneous coronary interventions. Its unique properties, including a relatively short half-life, an anticoagulation effect that closely correlates with activated clotting time, and an alternate metabolic pathway for elimination, make bivalirudin an attractive agent for cardiopulmonary bypass in patients with type II heparin induced-thrombocytopenia. We report our experience using bivalirudin in 2 patients undergoing coronary artery bypass grafting.
Interpretation of biomonitoring data in clinical medicine and the exposure sciences
DOE Office of Scientific and Technical Information (OSTI.GOV)
Williams, Bryan L.; Barr, Dana B.; Wright, J. Michael
2008-11-15
Biomonitoring has become a fundamental tool in both exposure science and clinical medicine. Despite significant analytical advances, the clinical use of environmental biomarkers remains in its infancy. Clinical use of environmental biomarkers poses some complex scientific and ethical challenges. The purpose of this paper is compare how the clinical and exposure sciences differ with respect to their interpretation and use of biological data. Additionally, the clinical use of environmental biomonitoring data is discussed. A case study is used to illustrate the complexities of conducting biomonitoring research on highly vulnerable populations in a clinical setting.
Towards reconstitution of membrane fusion mediated by SNAREs and other synaptic proteins
Brunger, Axel T.; Cipriano, Daniel J.; Diao, Jiajie
2015-01-01
Abstract Proteoliposomes have been widely used for in vitro studies of membrane fusion mediated by synaptic proteins. Initially, such studies were made with large unsynchronized ensembles of vesicles. Such ensemble assays limited the insights into the SNARE-mediated fusion mechanism that could be obtained from them. Single particle microscopy experiments can alleviate many of these limitations but they pose significant technical challenges. Here we summarize various approaches that have enabled studies of fusion mediated by SNAREs and other synaptic proteins at a single-particle level. Currently available methods are described and their advantages and limitations are discussed. PMID:25788028
Walker, L; Gruman, C; Robison, J
1998-08-01
This study examined Medicaid estate planning (MEP) through the experiences and perceptions of three groups in Connecticut: Medicaid eligibility workers (n = 128), elder law attorneys (n = 41), and certified financial planners (n = 29). Respondent groups varied significantly with regard to their perceptions of prevalence and magnitude of MEP, the nature of transferred assets, mechanisms for transfers, and characteristics of the "typical" client participating in asset divestiture for the purpose of qualifying for Medicaid. This substantial lack of concordance among those professionals most closely involved with MEP poses challenges for policy and research in this area.
[Highlights of hospital-based internal medicine in 2010: chief residents' perspective].
Uhlmann, Marc; Burnard, Jérôme; Cosma Rochat, Monica; Gabus, Vincent; Micheloud, Valérie Geiser; Gobin, Niels; Laurent, Jean-Christophe; Marino, Laura; Méan, Marie; Merz, Laurent; Regamey, Julien; Stadelmann, Raphaël
2011-02-02
Applying knowledge acquired from recent medical studies to patient care poses a daily challenge to physicians. Chief residents from the Department of Internal Medicine at the University Hospital of Lausanne carried out a review of some of the issues they considered important. The conclusions of these various publications may have a significant impact on the daily practice of hospital-based internal medicine. Modern medicine based on scientific studies is a reminder that in spite of the essential importance of clinical experience, it is crucial to confront it with the results of relevant publications from the medical literature.
Kazantzis, Nikolaos; Brownfield, Nicole R; Mosely, Livia; Usatoff, Alexsandra S; Flighty, Andrew J
2017-12-01
Treatment adherence has posed a substantial challenge not only for patients but also for the health profession for many decades. The last 5 years has witnessed significant attention toward adherence with cognitive behavioral therapy (CBT) homework for anxiety and depressive disorders, and adherence assessment methods have diversified. However, there remains a large component of the adherence process not assessed in CBT, with patient effort, engagement, and the known role for treatment appraisals and beliefs necessitating the pursuit of improved adherence assessment methods. Copyright © 2017 Elsevier Inc. All rights reserved.
Excitation spectra of retinal by multiconfiguration pair-density functional theory.
Dong, Sijia S; Gagliardi, Laura; Truhlar, Donald G
2018-03-07
Retinal is the chromophore in proteins responsible for vision. The absorption maximum of retinal is sensitive to mutations of the protein. However, it is not easy to predict the absorption spectrum of retinal accurately, and questions remain even after intensive investigation. Retinal poses a challenge for Kohn-Sham density functional theory (KS-DFT) because of the charge transfer character in its excitations, and it poses a challenge for wave function theory because the large size of the molecule makes multiconfigurational perturbation theory methods expensive. In this study, we demonstrate that multiconfiguration pair-density functional theory (MC-PDFT) provides an efficient way to predict the vertical excitation energies of 11-Z retinal, and it reproduces the experimentally determined absorption band widths and peak positions better than complete active space second-order perturbation theory (CASPT2). The consistency between complete active space self-consistent field (CASSCF) and KS-DFT dipole moments is demonstrated to be a useful criterion in selecting the active space. We also found that the nature of the terminal groups and the conformations of retinal play a significant role in the absorption spectrum. By considering a thermal distribution of conformations, we predict an absorption spectrum of retinal that is consistent with the experimental gas-phase spectrum. The location of the absorption peak and the spectral broadening based on MC-PDFT calculations agree better with experiments than those of CASPT2.
Systems Challenges for Hypersonic Vehicles
NASA Technical Reports Server (NTRS)
Hunt, James L.; Laruelle, Gerard; Wagner, Alain
1997-01-01
This paper examines the system challenges posed by fully reusable hypersonic cruise airplanes and access to space vehicles. Hydrocarbon and hydrogen fueled airplanes are considered with cruise speeds of Mach 5 and 10, respectively. The access to space matrix is examined. Airbreathing and rocket powered, single- and two-stage vehicles are considered. Reference vehicle architectures are presented. Major systems/subsystems challenges are described. Advanced, enhancing systems concepts as well as common system technologies are discussed.
Exploration Design Challenge 2014
2014-04-25
Sponsors of all of the semi-finalist teams in the Exploration Design Challenge pose for a group photo with the teams. Team ARES from the Governors School for Science and Technology in Hampton, Va. won the challenge with their radiation shield design, which will be built and flown aboard the Orion/EFT-1. The award was announced at the USA Science and Engineering Festival on April 25, 2014 at the Washington Convention Center. Photo Credit: (NASA/Aubrey Gemignani)
Exploration Design Challenge 2014
2014-04-25
Sponsors of Team ARES pose for a group photo with the winning high school team in the Exploration Design Challenge. Team ARES from the Governors School for Science and Technology in Hampton, Va. won the challenge with their radiation shield design, which will be built and flown aboard the Orion/EFT-1. The award was announced at the USA Science and Engineering Festival on April 25, 2014 at the Washington Convention Center. Photo Credit: (NASA/Aubrey Gemignani)
Application of Landscape Mosaic Technology to Complement Coral Reef Resource Mapping and Monitoring
2010-10-01
irregular shapes pose a challenge for divers trying to delimit live tissue boundaries. Future improvements in the 3D representation of benthic mosaics...benthic habitats can be especially challenging when the spatial extent of injuries exceeds tens of square meters. These large injuries are often too...the impacts of severe physical disturbance on coral reefs can be especially challenging when large-scale modifications to the reef structure takes
2011-09-28
Pipistrel-USA Taurus G4 Aircraft Pilot Robin Reid poses for a photograph during the 2011 Green Flight Challenge, sponsored by Google, held at the Charles M. Schulz Sonoma County Airport in Santa Rosa, Calif. on Thursday, Sept. 29, 2011. NASA and the Comparative Aircraft Flight Efficiency (CAFE) Foundation are having the challenge with the goal to advance technologies in fuel efficiency and reduced emissions with cleaner renewable fuels and electric aircraft. Photo Credit: (NASA/Bill Ingalls)
2011-09-28
Pipistrel-USA Taurus G4 Aircraft Pilot David Morss poses for a photograph during the 2011 Green Flight Challenge, sponsored by Google, held at the Charles M. Schulz Sonoma County Airport in Santa Rosa, Calif. on Thursday, Sept. 29, 2011. NASA and the Comparative Aircraft Flight Efficiency (CAFE) Foundation are having the challenge with the goal to advance technologies in fuel efficiency and reduced emissions with cleaner renewable fuels and electric aircraft. Photo Credit: (NASA/Bill Ingalls)
NASA Technical Reports Server (NTRS)
Rothhaar, Paul M.; Murphy, Patrick C.; Bacon, Barton J.; Gregory, Irene M.; Grauer, Jared A.; Busan, Ronald C.; Croom, Mark A.
2014-01-01
Control of complex Vertical Take-Off and Landing (VTOL) aircraft traversing from hovering to wing born flight mode and back poses notoriously difficult modeling, simulation, control, and flight-testing challenges. This paper provides an overview of the techniques and advances required to develop the GL-10 tilt-wing, tilt-tail, long endurance, VTOL aircraft control system. The GL-10 prototype's unusual and complex configuration requires application of state-of-the-art techniques and some significant advances in wind tunnel infrastructure automation, efficient Design Of Experiments (DOE) tunnel test techniques, modeling, multi-body equations of motion, multi-body actuator models, simulation, control algorithm design, and flight test avionics, testing, and analysis. The following compendium surveys key disciplines required to develop an effective control system for this challenging vehicle in this on-going effort.
Towards the novel reasoning among particles in PSO by the use of RDF and SPARQL.
Fister, Iztok; Yang, Xin-She; Ljubič, Karin; Fister, Dušan; Brest, Janez; Fister, Iztok
2014-01-01
The significant development of the Internet has posed some new challenges and many new programming tools have been developed to address such challenges. Today, semantic web is a modern paradigm for representing and accessing knowledge data on the Internet. This paper tries to use the semantic tools such as resource definition framework (RDF) and RDF query language (SPARQL) for the optimization purpose. These tools are combined with particle swarm optimization (PSO) and the selection of the best solutions depends on its fitness. Instead of the local best solution, a neighborhood of solutions for each particle can be defined and used for the calculation of the new position, based on the key ideas from semantic web domain. The preliminary results by optimizing ten benchmark functions showed the promising results and thus this method should be investigated further.
The Twin Epidemics of Tuberculosis and HIV.
Varghese, George M; Janardhanan, Jeshina; Ralph, Ravikar; Abraham, Ooriapadickal C
2013-02-01
The deadly combination of tuberculosis (TB) and human immunodeficiency virus (HIV) currently ravaging the world, taking a toll of about 0.35 million people every year, is one of the major public health crises of the decade. Throughout the course of HIV infection, the risk of acquisition, reactivation, and reinfection of TB keeps increasing substantially as the immune deficiency progresses. TB coinfected patients inadvertently facilitate HIV infection by release of the proinflammatory cytokines and overexpression of coreceptors CXCR4 and CCR5; thereby, the progression of each is facilitated. The difficulties in diagnosing active tuberculosis in HIV-infected individuals poses a great challenge that is further complicated by the challenges in identification of latent TB infection, creating a setback to preventive therapy. Furthermore, prescribing antituberculous therapy and antiretroviral therapy together poses several management challenges, including drug interactions, added toxicities, and TB immune reconstitution inflammatory syndrome. The current approach to diagnosis, prevention, and treatment strategies in TB and HIV coinfected individuals, along with epidemiology and overview of pathogenetic interplay of both microbes, is reviewed here.
Murphy, Colin G; Chrea, Bopha; Molloy, Alan P; Nicholson, Paul
2013-03-20
Achondroplasia is an autosomal dominant dwarfing condition that represents the most common form of skeletal dysplasia. The disease is caused by a mutation in the gene encoding fibroblast growth factor receptor 3 (FGFR3) found at the p16.3 locus on chromosome 4 which results in severe inhibition of subchondral bone growth. Anatomic variations, including articular and periarticular deformities classically seen with this condition, amplify the complexity of fracture fixation. Blood volume loss, age-related bone fragility, component selection and positioning pose serious orthopaedic challenges. Concomitant cardiovascular, respiratory and neurological comorbidities pose additional high-risk perioperative considerations. Despite an estimated prevalence of 1:25 000 in the general population, there is little literature concerning the operative and postoperative treatment challenges faced by orthopaedic surgeons dealing with fracture management on a patient with this condition. We present a case of an intercondylar femoral fracture in an elderly achondroplastic lady successfully treated with percutaneous screw fixation.
Chess from Square a1: Incorporating Chess into the Gifted Class
ERIC Educational Resources Information Center
Adams, Thomasina C. P.
2012-01-01
Teachers of gifted students often are challenged to find ways to stimulate critical thinking and problem-solving skills. School chess clubs are one way of meeting that challenge. This article poses how games such as chess affect learning and gifted students. Two detailed strategies for teaching chess to students beginning in kindergarten are…
Antibiotic resistance: a physicist’s view
NASA Astrophysics Data System (ADS)
Allen, Rosalind; Waclaw, Bartłomiej
2016-08-01
The problem of antibiotic resistance poses challenges across many disciplines. One such challenge is to understand the fundamental science of how antibiotics work, and how resistance to them can emerge. This is an area where physicists can make important contributions. Here, we highlight cases where this is already happening, and suggest directions for further physics involvement in antimicrobial research.
Cultural Factors Related to the Hidden Curriculum for Students with Autism and Related Disabilities
ERIC Educational Resources Information Center
Lee, Hyo Jung
2011-01-01
The hidden curriculum, the unwritten rules and standards for social conduct that most people take for granted and learn more or less automatically, poses a challenge for many individuals on the autism spectrum because of deficits in social cognition and social interaction skills. Compounding challenges are cultural factors, such as age, ethnicity,…
ERIC Educational Resources Information Center
Sandri, Orana; Holdsworth, Sarah; Thomas, Ian
2018-01-01
Purpose: The purpose of this paper is to highlight both the need for measurement of graduate capabilities post-degree completion and the challenges posed by such a task. Higher education institutions provide an important site of learning that can equip future professionals with capabilities to manage and respond to complex sustainability…
ESL Reading Textbooks vs. University Textbooks: Are We Giving Our Students the Input They May Need?
ERIC Educational Resources Information Center
Miller, Don
2011-01-01
Developing reading skills in a second language presents learners with many challenges, including lexico-grammatical decoding. An additional challenge is posed by the different registers of written text and the associated lexico-grammatical features with which learners must contend. Questioning the efficacy of using non-academic reading texts in…
ERIC Educational Resources Information Center
Badawood, Ashraf Mohammad
2011-01-01
The blended learning (BL) approach provides an efficient and effective instructional experience. However, adopting BL poses some challenge to faculty; the most important obstacle found in this research is faculty's lack of knowledge regarding the use of technology in their teaching. This challenge prompted the researcher to identify a solution…
Strategies for Coping with the Challenges of Incarceration among Nigerian Prison Inmates
ERIC Educational Resources Information Center
Agbakwuru, Chikwe; Awujo, Grace C.
2016-01-01
This paper investigated the strategies for coping with the challenges of incarceration among inmates of Port Harcourt Prison, Nigeria. The population was 2,997 inmates of the prison while the sample was 250 inmates drawn through stratified random sampling technique from the same Port Harcourt prison. Six research questions were posed and data for…
The Challenges of Political Instruction in a Post-9/11 United States
ERIC Educational Resources Information Center
Journell, Wayne
2011-01-01
In the decade since the attacks of September 11th, the political climate in the United States has become increasingly intolerant of opposing viewpoints. This climate, made nearly ubiquitous by 24-hour news cycles and increased exposure to political media, poses quite a challenge to teachers wishing to broach political topics as part of their…
Educational Elements of a Comprehensive State Policy on Aging.
ERIC Educational Resources Information Center
New York State Education Dept., Albany. Office for Policy Analysis.
The aging of New York State's population poses both a challenge and an opportunity for the major institutions of society. The challenge facing educators is to develop a comprehensive strategy to mobilize the capacity of the educational system to address the multiple needs of an aging population in the context of existing social and economic…
Tetralogy of Fallot with pheochromocytoma: an unusual therapeutic challenge.
Balakrishnan, Gautam; Ravikumar, Ratnagiri; Rao, Suresh; Balakrishnan, Komarakshi R
2013-08-01
An adult with unoperated tetralogy of Fallot diagnosed simultaneously with pheochromocytoma is extremely rare. This poses obvious diagnostic and therapeutic challenges. A 29-year-old woman with these conditions was successfully operated on for both diseases in the same hospitalization. There is some interesting speculation regarding the association of pheochromocytoma with uncorrected cyanotic congenital heart disease.
Climate Change Education: Preparing Future and Current Business Leaders--A Workshop Summary
ERIC Educational Resources Information Center
Storksdieck, Martin
2014-01-01
Climate change poses challenges as well as opportunities for businesses and, broadly speaking for the entire economy. Businesses will be challenged to provide services or products with less harmful influence on the climate; respond to a changing policy, regulatory, and market environment; and provide new services and products to help address the…
ERIC Educational Resources Information Center
Judith, Kate; Bull, David
2016-01-01
The implementation of open educational resources (OER) at the course level in higher education poses numerous challenges to education practitioners--ranging from discoverability challenges to the lack of knowledge on how to best localize and utilize OER as courseware. Drawing on case studies of OER initiatives globally, the article discusses…
ERIC Educational Resources Information Center
O'Malley, Michael P.; Long, Tanya A.; King, Jeffry
2015-01-01
Multiple and complex issues simultaneously present themselves for the principal's attention. Learning how to identify, prioritize, synthesize, and act in relation to these issues poses a particular challenge to early career principals. This case study engages aspiring and current school leaders in critical reflection upon leadership opportunities…
Futures research: A neglected dimension in environmental policy and planning
David N. Bengston
2012-01-01
The need for strategic foresight in an increasingly complex and rapidly changing world poses a formidable challenge to environmental planners and policy makers. Th is paper introduces futures research as an under used but fruitful set of approaches to addressing this challenge. Futures research is a transdisciplinary social science that uses a wide range of methods to...
ERIC Educational Resources Information Center
Munday, Jenni; Smith, Wyverne
2010-01-01
Pre-service teacher degree programs are increasingly crowded with subjects covering the wide gamut of knowledge a teacher requires. Ensuring musical knowledge and language for classroom teaching poses a difficult problem for teacher educators. This article examines the challenges of including in the pre-service classroom teaching program a music…
Challenging the Achievement Gap by Disrupting Concepts of "Normalcy." The Complete Essays
ERIC Educational Resources Information Center
Draxton, Shawna; Radley, Kirstee; Murphy, Joanne; Nevin, Ann; Nishimura, Trisha; Hagge, Darla; Taniform, Lawrence
2011-01-01
We propose that Disability Studies in Education (DSE) offers a framework that (a) grounds policy and practice in the experiences and perspectives of people with disabilities, (c) challenges practices/ policy that isolate, de-humanize individuals, and (c) leads to new questions to pose. In this session, we describe the pedagogy that we used to…
Second Language Prosody and Oral Reading Comprehension in Learners of Brazilian Portuguese
ERIC Educational Resources Information Center
McCune, W. M. Duce, II
2011-01-01
Learning to read can pose a major challenge to students, and much of this challenge is due to the fact that written language is necessarily impoverished when compared to the rich, continuous speech signal. Prosodic elements of language are scarcely represented in written text, and while oral reading prosody has been addressed in the literature…
ERIC Educational Resources Information Center
Wilson, Dawna; Lowry, Kimberly M.
2017-01-01
Recent national attention on college completion poses unique challenges and opportunities for community colleges. Moving underprepared students through basic skills educational courses to degree attainment represents an ongoing challenge. With more than 60% of community college students enrolled in remedial education, 2-year institutions must…
ERIC Educational Resources Information Center
Phillips, Neil; Rose, John
2010-01-01
Background: Individuals with intellectual disabilities are more likely to experience a breakdown in their community residential placement if they display "challenging" behaviour. However, some individuals with behaviour that poses a severe challenge live successfully in community services long-term, indicating that other factors are also…
ERIC Educational Resources Information Center
Bulgren, Janis; Deshler, Donald D.; Lenz, B. Keith
2007-01-01
The understanding and use of historical concepts specified in national history standards pose many challenges to students. These challenges include both the acquisition of content knowledge and the use of that knowledge in ways that require higher order thinking. All students, including adolescents with learning disabilities (LD), are expected to…
Building an Integrated Student Information System in a K-12 School System
ERIC Educational Resources Information Center
Steenkamp, Annette Lerine; Basal, Abdelraheem
2010-01-01
The task of managing an IT system in a school environment poses unique challenges. For example, one of the greatest challenges facing individual schools is the lack of integration between various information systems. The present situation in many schools is that there are many disconnected systems managing many different tasks. Systems with…
Working forests, forest health and management challenges in the redwood region
Ken Pimlott
2017-01-01
As California continues into a fifth year of drought, tree mortality enhanced by the unprecedented bark beetle epidemic contributes to wildfires that continue to increase in frequency and severity. Recent fires have posed increasing fire suppression challenges, life safety concerns, post fire watershed impacts and lasting damage to forested landscapes. The ability of...
The path for incorporating new approach methods and technologies into quantitative chemical risk assessment poses a diverse set of scientific challenges. These challenges include sufficient coverage of toxicological mechanisms to meaningfully interpret negative test results, dev...
Wanting to Learn: A Necessary Condition for the Effectiveness of Instructional Design
ERIC Educational Resources Information Center
Gropper, George L.
2015-01-01
There are inevitable challenges standing in the way of the success of any approach to Instructional Design. Some are being faced up to. Some are not. Not least among them is the absence of empirically established principles undergirding Instructional Design prescriptions. The challenge it poses is to their reliability and validity. Nothing that…
ERIC Educational Resources Information Center
Boyden, Jo
Child labor, which is children's work that is exploitative and dangerous, poses a major human rights and socioeconomic challenge. Universal primary education may be the most effective instrument for meeting this challenge. The expansion of compulsory primary schooling could reduce hours of work by children and help them protect themselves against…
Hypoxia and flight performance of military instructor pilots in a flight simulator.
Temme, Leonard A; Still, David L; Acromite, Michael T
2010-07-01
Military aircrew and other operational personnel frequently perform their duties at altitudes posing a significant hypoxia risk, often with limited access to supplemental oxygen. Despite the significant risk hypoxia poses, there are few studies relating it to primary flight performance, which is the purpose of the present study. Objective, quantitative measures of aircraft control were collected from 14 experienced, active duty instructor pilot volunteers as they breathed an air/nitrogen mix that provided an oxygen partial pressure equivalent to the atmosphere at 18,000 ft (5486.4 m) above mean sea level. The flight task required holding a constant airspeed, altitude, and heading at an airspeed significantly slower than the aircraft's minimum drag speed. The simulated aircraft's inherent instability at the target speed challenged the pilot to maintain constant control of the aircraft in order to minimize deviations from the assigned flight parameters. Each pilot's flight performance was evaluated by measuring all deviations from assigned target values. Hypoxia degraded the pilot's precision of altitude and airspeed control by 53%, a statistically significant decrease in flight performance. The effect on heading control effects was not statistically significant. There was no evidence of performance differences when breathing room air pre- and post-hypoxia. Moderate levels of hypoxia degraded the ability of military instructor pilots to perform a precision slow flight task. This is one of a small number of studies to quantify an effect of hypoxia on primary flight performance.
A Bayesian Framework for Human Body Pose Tracking from Depth Image Sequences
Zhu, Youding; Fujimura, Kikuo
2010-01-01
This paper addresses the problem of accurate and robust tracking of 3D human body pose from depth image sequences. Recovering the large number of degrees of freedom in human body movements from a depth image sequence is challenging due to the need to resolve the depth ambiguity caused by self-occlusions and the difficulty to recover from tracking failure. Human body poses could be estimated through model fitting using dense correspondences between depth data and an articulated human model (local optimization method). Although it usually achieves a high accuracy due to dense correspondences, it may fail to recover from tracking failure. Alternately, human pose may be reconstructed by detecting and tracking human body anatomical landmarks (key-points) based on low-level depth image analysis. While this method (key-point based method) is robust and recovers from tracking failure, its pose estimation accuracy depends solely on image-based localization accuracy of key-points. To address these limitations, we present a flexible Bayesian framework for integrating pose estimation results obtained by methods based on key-points and local optimization. Experimental results are shown and performance comparison is presented to demonstrate the effectiveness of the proposed approach. PMID:22399933
Kirshblum, S C; Biering-Sorensen, F; Betz, R; Burns, S; Donovan, W; Graves, D E; Johansen, M; Jones, L; Mulcahey, M J; Rodriguez, G M; Schmidt-Read, M; Steeves, J D; Tansey, K; Waring, W
2014-03-01
The International Standards for the Neurological Classification of Spinal Cord Injury (ISNCSCI) is routinely used to determine the levels of injury and to classify the severity of the injury. Questions are often posed to the International Standards Committee of the American Spinal Injury Association regarding the classification. The committee felt that disseminating some of the challenging questions posed, as well as the responses, would be of benefit for professionals utilizing the ISNCSCI. Case scenarios that were submitted to the committee are presented with the responses as well as the thought processes considered by the committee members. The importance of this documentation is to clarify some points as well as update the SCI community regarding possible revisions that will be needed in the future based upon some rules that require clarification.
Dr. David Brown poses with a portrait of Ronald McNair
NASA Technical Reports Server (NTRS)
1999-01-01
In the gymnasium of Ronald McNair Magnet School in Cocoa, Fla., Dr. David Brown, a NASA astronaut, poses with a portrait of NASA astronaut Ronald McNair. The portrait was presented to the school by Walt Disney World during a tribute to McNair. The school had previously been renamed for the fallen astronaut who was one of a crew of seven who lost their lives during an accident following launch of the Space Shuttle Challenger in January 1986.
Fire in Mediterranean climate ecosystems: a comparative overview
Keeley, Jon E.
2012-01-01
Four regions of the world share a similar climate and structurally similar plant communities with the Mediterranean Basin. These five areas, known collectively as "mediterranean-type climate (MTC) regions", are dominated by evergreen sclerophyllous-leaved shrublands, semi-deciduous scrub, and woodlands, all of which are prone to widespread crown fires. Summer droughts produce an annual fire hazard that contributes to a highly predictable fire regime. Fire has been an important factor driving the convergence of these systems and is reflected in plant traits such as lignotubers in resprouting shrubs and delayed reproduction that restricts recruitment to a postfire pulse of seedlings. On fertile soils where postfire resprouting is very rapid, opportunities for postfire seedling recruitment are limited and thus these woody taxa have not opted for delaying reproduction. Such fire-independent recruitment is widespread in the floras of MTC regions of the Mediterranean Basin and California and postfire seeding tends to dominate at the more arid end of the gradient. Due to very different geological histories in South Africa and Western Australia, substrates are nutrient poor and thus postfire resprouters do not pose a similar competitive challenge to seedlings and thus postfire seeding is very widespread in these floras. Although circumstantial evidence suggests that the MTC region of Chile had fire-prone landscapes in the Tertiary, these were lost with the late Miocene completion of the Andean uplift, which now blocks summer lightning storms from moving into the region. Today these five regions pose a significant fire management challenge due to the annual fire hazard and metropolitan centers juxtaposed with highly flammable vegetation. This challenge varies across the five MTC landscapes as a function of differences in regional fuel loads and population density.
NASA Astrophysics Data System (ADS)
Deser, C.
2017-12-01
Natural climate variability occurs over a wide range of time and space scales as a result of processes intrinsic to the atmosphere, the ocean, and their coupled interactions. Such internally generated climate fluctuations pose significant challenges for the identification of externally forced climate signals such as those driven by volcanic eruptions or anthropogenic increases in greenhouse gases. This challenge is exacerbated for regional climate responses evaluated from short (< 50 years) data records. The limited duration of the observations also places strong constraints on how well the spatial and temporal characteristics of natural climate variability are known, especially on multi-decadal time scales. The observational constraints, in turn, pose challenges for evaluation of climate models, including their representation of internal variability and assessing the accuracy of their responses to natural and anthropogenic radiative forcings. A promising new approach to climate model assessment is the advent of large (10-100 member) "initial-condition" ensembles of climate change simulations with individual models. Such ensembles allow for accurate determination, and straightforward separation, of externally forced climate signals and internal climate variability on regional scales. The range of climate trajectories in a given model ensemble results from the fact that each simulation represents a particular sequence of internal variability superimposed upon a common forced response. This makes clear that nature's single realization is only one of many that could have unfolded. This perspective leads to a rethinking of approaches to climate model evaluation that incorporate observational uncertainty due to limited sampling of internal variability. Illustrative examples across a range of well-known climate phenomena including ENSO, volcanic eruptions, and anthropogenic climate change will be discussed.
NASA Astrophysics Data System (ADS)
Selwa, Edithe; Elisée, Eddy; Zavala, Agustin; Iorga, Bogdan I.
2018-01-01
Our participation to the D3R Grand Challenge 2 involved a protocol in two steps, with an initial analysis of the available structural data from the PDB allowing the selection of the most appropriate combination of docking software and scoring function. Subsequent docking calculations showed that the pose prediction can be carried out with a certain precision, but this is dependent on the specific nature of the ligands. The correct ranking of docking poses is still a problem and cannot be successful in the absence of good pose predictions. Our free energy calculations on two different subsets provided contrasted results, which might have the origin in non-optimal force field parameters associated with the sulfonamide chemical moiety.
ERIC Educational Resources Information Center
Alozie, Nonye M.; Moje, Elizabeth Birr; Krajcik, Joseph S.
2010-01-01
One goal of project-based science is to promote the development of scientific discourse communities in classrooms. Holding rich high school scientific discussions is challenging, especially when the demands of content and norms of high school science pose challenges to their enactment. There is little research on how high school teachers enact…
ERIC Educational Resources Information Center
Corby, Deirdre; Taggart, Laurence; Cousins, Wendy
2018-01-01
Including the inner perspectives of people who have intellectual disability can pose methodological challenges to qualitative researchers. This article explains how the Listening Guide was applied as an additional step in the analysis during a study which used hermeneutic interviews with people with intellectual disability as the sole method of…
At-Risk Students: An Analysis of School Improvement Grants in the State of Missouri
ERIC Educational Resources Information Center
Witherspoon, Anissa
2017-01-01
The educational system in the United States continues to pose many challenges for law and policy makers. Many of these challenges can be traced back to two landmark cases, "Plessy vs. Ferguson" and "Brown vs. Board of Education of Topeka." And, while the U.S. Department of Education developed programs to address many of these…
Piano Pedagogy with a Student Who Is Blind: An Australian Case
ERIC Educational Resources Information Center
Power, Anne; McCormack, Dorothy
2012-01-01
Teaching and learning piano poses challenges when the student is clinically blind. This article addresses the following question: What can be learned from a case study of teaching piano successfully to a student who is blind? The article has three purposes. The first is to document the achievements of a young student who met these challenges. The…
Overview of contemporary issues of forest research and management in China
Hong S. He; Stephen R. Shifley; Frank R., III Thompson
2011-01-01
With 207 million ha of forest covering 22% of its land area, China ranks fifth in the world in forest area. Rapid economic growth, climate change, and forest disturbances pose new, complex challenges for forest research and management. Progress in meeting these challenges is relevant beyond China, because China's forests represent 34% of Asia's forests and 5...
A Short Twenty Years: Meeting the Challenges Facing Teachers Who Bring Rwanda into the Classroom
ERIC Educational Resources Information Center
Gudgel, Mark
2013-01-01
As the twentieth anniversary of the 1994 genocide in Rwanda approaches, Mark Gudgel argues that we should face the challenges posed by teaching about Rwanda. Drawing on his experience as a history teacher in the US, his experience researching and supporting others' classrooms in the US and UK, his training in Holocaust education and his knowledge…
A New Pathway for E-Learning: From Distribution to Collaboration and Competence in E-Learning
ERIC Educational Resources Information Center
Ehlers, Ulf-Daniel
2008-01-01
The article describes the current challenge for e-learning in higher education, which is to support development of competence. This poses great challenges to e-learning in higher education, mainly because the way it has been designed, in many cases, does not fit with supporting competence development. Rather, it facilitates the mere transfer of…
ERIC Educational Resources Information Center
Malchiodi, Alessandro
2013-01-01
This dissertation comprises three essays that empirically examine the educational outcomes of for-profit college students, military enlistees and immigrant youth. All of these are groups of "non-average" students that, in different contexts, pose challenges to the traditional provision of education. Therefore, their outcomes need to be…
ERIC Educational Resources Information Center
Malchiodi, Alessandro
2014-01-01
This dissertation comprises three essays that empirically examine the educational outcomes of for-profit college students, military enlistees and immigrant youth. All of these are groups of "non-average" students that, in different contexts, pose challenges to the traditional provision of education. Therefore, their outcomes need to be…
ERIC Educational Resources Information Center
Forbes, Melissa
2016-01-01
This article reviews relevant literature to provide a rationale for the use of collaborative learning for first year music practice courses at an Australian regional university. Higher music education is still grappling with the challenges posed by the Dawkins Review and ongoing reforms in the sector. These challenges include increased public…
ERIC Educational Resources Information Center
Stott, Philip
2016-01-01
Wholly online presentation of courses is becoming increasingly common, but poor levels of student engagement pose challenges to institutions, instructors and students. In this paper, I explore the risks arising from those challenges using an analysis of the presentation of a wildlife management course as a model, comparing data about levels of…
Challenges to the Learning Organization in the Context of Generational Diversity and Social Networks
ERIC Educational Resources Information Center
Kaminska, Renata; Borzillo, Stefano
2018-01-01
Purpose: The purpose of this paper is to gain a better understanding of the challenges to the emergence of a learning organization (LO) posed by a context of generational diversity and an enterprise social networking system (ESNS). Design/methodology/approach: This study uses a qualitative methodology based on an analysis of 20 semi-structured…
Climate Change: Meeting the Challenge
ERIC Educational Resources Information Center
Chance, Paul; Heward, William L.
2010-01-01
In "Climate Change: Meeting the Challenge," we conclude the special section by assuming that you have been persuaded by Thompson's paper or other evidence that global warming is real and poses a threat that must be dealt with, and that for now the only way to deal with it is by changing behavior. Then we ask what you, as behavior analysts, can do…
Leading Change for the Implementation of Common Core State Standards in Rural School Districts
ERIC Educational Resources Information Center
Lopez, Paul; Wise, Donald
2015-01-01
Rural school districts across the nation, with their limited resources, face daunting challenges posed by the implementation of the Common Core State Standards. This article presents a recent study of 13 rural school districts in the Central Valley of California and how these districts are responding to those challenges. A total of 352 teachers…
ERIC Educational Resources Information Center
Fang, Zhihui
2008-01-01
As students transition from primary to intermediate grades, the kind of materials that they are expected to read and write become more heavily dominated by expository texts. Expository texts contain grammatical patterns that are distinct from those used in primary-grade storybooks. These linguistic features pose new comprehension challenges for…
Technological Innovation of Higher Education in New Zealand: A Wicked Problem?
ERIC Educational Resources Information Center
Marshall, Stephen
2016-01-01
New Zealand, like many countries, faces the challenge of building and sustaining an educated population. Particular challenges are posed by the need to educate an increasing proportion of the population to higher levels in order to support the growth of a modern skills and knowledge economy, as opposed to an economy built on low-cost labour and…
ERIC Educational Resources Information Center
Allely, C. S.; Doolin, O.; Gillberg, C.; Gillberg, I. C.; Puckering, C.; Smillie, M.; McConnachie, A.; Heron, J.; Golding, J.; Wilson, P.
2012-01-01
One of the challenges of developmental psychopathology is to determine whether identifiable pathways to developmental disorders exist in the first months or years of life. Early identification of such disorders poses a similar challenge for clinical services. Using data from a large contemporary birth cohort, we examined whether psychopathology at…
Gardell, Alison M.; Yang, Jun; Sacchi, Romina; Fangue, Nann A.; Hammock, Bruce D.; Kültz, Dietmar
2013-01-01
SUMMARY This study aimed to determine the regulation of the de novo myo-inositol biosynthetic (MIB) pathway in Mozambique tilapia (Oreochromis mossambicus) brain following acute (25 ppt) and chronic (30, 60 and 90 ppt) salinity acclimations. The MIB pathway plays an important role in accumulating the compatible osmolyte, myo-inositol, in cells in response to hyperosmotic challenge and consists of two enzymes, myo-inositol phosphate synthase and inositol monophosphatase. In tilapia brain, MIB enzyme transcriptional regulation was found to robustly increase in a time (acute acclimation) or dose (chronic acclimation) dependent manner. Blood plasma osmolality and Na+ and Cl− concentrations were also measured and significantly increased in response to both acute and chronic salinity challenges. Interestingly, highly significant positive correlations were found between MIB enzyme mRNA and blood plasma osmolality in both acute and chronic salinity acclimations. Additionally, a mass spectrometry assay was established and used to quantify total myo-inositol concentration in tilapia brain, which closely mirrored the hyperosmotic MIB pathway induction. Thus, myo-inositol is a major compatible osmolyte that is accumulated in brain cells when exposed to acute and chronic hyperosmotic challenge. These data show that the MIB pathway is highly induced in response to environmental salinity challenge in tilapia brain and that this induction is likely prompted by increases in blood plasma osmolality. Because the MIB pathway uses glucose-6-phosphate as a substrate and large amounts of myo-inositol are being synthesized, our data also illustrate that the MIB pathway likely contributes to the high energetic demand posed by salinity challenge. PMID:24072790
Evaluating the risks of clinical research: direct comparative analysis.
Rid, Annette; Abdoler, Emily; Roberson-Nay, Roxann; Pine, Daniel S; Wendler, David
2014-09-01
Many guidelines and regulations allow children and adolescents to be enrolled in research without the prospect of clinical benefit when it poses minimal risk. However, few systematic methods exist to determine when research risks are minimal. This situation has led to significant variation in minimal risk judgments, raising concern that some children are not being adequately protected. To address this concern, we describe a new method for implementing the widely endorsed "risks of daily life" standard for minimal risk. This standard defines research risks as minimal when they do not exceed the risks posed by daily life activities or routine examinations. This study employed a conceptual and normative analysis, and use of an illustrative example. Different risks are composed of the same basic elements: Type, likelihood, and magnitude of harm. Hence, one can compare the risks of research and the risks of daily life by comparing the respective basic elements with each other. We use this insight to develop a systematic method, direct comparative analysis, for implementing the "risks of daily life" standard for minimal risk. The method offers a way of evaluating research procedures that pose the same types of risk as daily life activities, such as the risk of experiencing anxiety, stress, or other psychological harm. We thus illustrate how direct comparative analysis can be applied in practice by using it to evaluate whether the anxiety induced by a respiratory CO2 challenge poses minimal or greater than minimal risks in children and adolescents. Direct comparative analysis is a systematic method for applying the "risks of daily life" standard for minimal risk to research procedures that pose the same types of risk as daily life activities. It thereby offers a method to protect children and adolescents in research, while ensuring that important studies are not blocked because of unwarranted concerns about research risks.
Evaluating the Risks of Clinical Research: Direct Comparative Analysis
Abdoler, Emily; Roberson-Nay, Roxann; Pine, Daniel S.; Wendler, David
2014-01-01
Abstract Objectives: Many guidelines and regulations allow children and adolescents to be enrolled in research without the prospect of clinical benefit when it poses minimal risk. However, few systematic methods exist to determine when research risks are minimal. This situation has led to significant variation in minimal risk judgments, raising concern that some children are not being adequately protected. To address this concern, we describe a new method for implementing the widely endorsed “risks of daily life” standard for minimal risk. This standard defines research risks as minimal when they do not exceed the risks posed by daily life activities or routine examinations. Methods: This study employed a conceptual and normative analysis, and use of an illustrative example. Results: Different risks are composed of the same basic elements: Type, likelihood, and magnitude of harm. Hence, one can compare the risks of research and the risks of daily life by comparing the respective basic elements with each other. We use this insight to develop a systematic method, direct comparative analysis, for implementing the “risks of daily life” standard for minimal risk. The method offers a way of evaluating research procedures that pose the same types of risk as daily life activities, such as the risk of experiencing anxiety, stress, or other psychological harm. We thus illustrate how direct comparative analysis can be applied in practice by using it to evaluate whether the anxiety induced by a respiratory CO2 challenge poses minimal or greater than minimal risks in children and adolescents. Conclusions: Direct comparative analysis is a systematic method for applying the “risks of daily life” standard for minimal risk to research procedures that pose the same types of risk as daily life activities. It thereby offers a method to protect children and adolescents in research, while ensuring that important studies are not blocked because of unwarranted concerns about research risks. PMID:25210944
SRTM Stereo Pair with Landsat Overlay: Los Angeles to San Joaquin Valley, California
2000-09-21
California topography poses challenges for road builders. Northwest of Los Angeles, deformation of Earth crust along the Pacific-North American crustal plate boundary has made transportation difficult.
Keep Counting Those Boxes--There's More.
ERIC Educational Resources Information Center
Mingus, Tabitha T. Y.; Grassl, Richard M.
1998-01-01
Poses and solves several related extensions involving enumerating squares and rectangles. Describes how problem extensions can be developed and used in the classroom to motivate and challenge teachers and students to exert themselves mathematically. (ASK)
The structural science of functional materials.
Catlow, C Richard A
2018-01-01
The growing complexity of functional materials and the major challenges this poses to structural science are discussed. The diversity of structural materials science and the contributions that computation is making to the field are highlighted.
Contaminated Sediment Core Profiling
Evaluating the environmental risk of sites containing contaminated sediments often poses major challenges due in part to the absence of detailed information available for a given location. Sediment core profiling is often utilized during preliminary environmental investigations ...
Frambach, Janneke M; Driessen, Erik W; Chan, Li-Chong; van der Vleuten, Cees P M
2012-08-01
Medical schools worldwide are increasingly switching to student-centred methods such as problem-based learning (PBL) to foster lifelong self-directed learning (SDL). The cross-cultural applicability of these methods has been questioned because of their Western origins and because education contexts and learning approaches differ across cultures. This study evaluated PBL's cross-cultural applicability by investigating how it is applied in three medical schools in regions with different cultures in, respectively, East Asia, the Middle East and Western Europe. Specifically, it investigated how students' cultural backgrounds impact on SDL in PBL and how this impact affects students. A qualitative, cross-cultural, comparative case study was conducted in three medical schools. Data were collected through 88 semi-structured, in-depth interviews with Year 1 and 3 students, tutors and key persons involved in PBL, 32 observations of Year 1 and 3 PBL tutorials, document analysis, and contextual information. The data were thematically analysed using the template analysis method. Comparisons were made among the three medical schools and between Year 1 and 3 students across and within the schools. The cultural factors of uncertainty and tradition posed a challenge to Middle Eastern students' SDL. Hierarchy posed a challenge to Asian students and achievement impacted on both sets of non-Western students. These factors were less applicable to European students, although the latter did experience some challenges. Several contextual factors inhibited or enhanced SDL across the cases. As students grew used to PBL, SDL skills increased across the cases, albeit to different degrees. Although cultural factors can pose a challenge to the application of PBL in non-Western settings, it appears that PBL can be applied in different cultural contexts. However, its globalisation does not postulate uniform processes and outcomes, and culturally sensitive alternatives might be developed. © Blackwell Publishing Ltd 2012.
Endodontics and the ageing patient.
Johnstone, M; Parashos, P
2015-03-01
Patients are living longer and the rate of edentulism is decreasing. Endodontic treatment is an essential part of maintaining the health and well-being of the elderly. Retention of natural teeth improves the quality of life and the overall health and longevity of ageing patients. Also, teeth that might be otherwise extracted may be strategically valuable to retain a prosthesis, and elderly patients are more likely to have medical complications that may prevent dental extractions from being safely performed. The technical goals of endodontic treatment in the elderly are the same as those for younger patients. However, the pulpo-dentinal complex undergoes calcific changes over time, which may pose challenges for the clinician. The purposes of this review are to discuss age changes in the pulp and the challenges posed by diagnosing, treatment planning and treating the elderly endodontic patient. © 2015 Australian Dental Association.
Gorman, Susanna M
2011-09-01
Australian Human Research Ethics Committees (HRECs) have to contend with ever-increasing workloads and responsibilities which go well beyond questions of mere ethics. In this article, I shall examine how the roles of HRECs have changed, and show how this is reflected in the iterations of the National Statement on Ethical Conduct in Human Research 2007 (NS). In particular I suggest that the focus of the National Statement has shifted to concentrate on matters of research governance at the expense of research ethics, compounded by its linkage to the Australian Code for the Responsible Conduct of Research (2007) in its most recent iteration. I shall explore some of the challenges this poses for HRECs and institutions and the risks it poses to ensuring that Australian researchers receive clear ethical guidance and review.
Drug resistance in eukaryotic microorganisms
Fairlamb, Alan H.; Gow, Neil A. R.; Matthews, Keith R.; Waters, Andrew P.
2016-01-01
Eukaryotic microbial pathogens are major contributors to illness and death globally. Although much of their impact can be controlled by drug therapy as with prokaryotic microorganisms, the emergence of drug resistance has threatened these treatment efforts. Here, we discuss the challenges posed by eukaryotic microbial pathogens and how these are similar to, or differ from, the challenges of prokaryotic antibiotic resistance. The therapies used for several major eukaryotic microorganisms are then detailed, and the mechanisms that they have evolved to overcome these therapies are described. The rapid emergence of resistance and the restricted pipeline of new drug therapies pose considerable risks to global health and are particularly acute in the developing world. Nonetheless, we detail how the integration of new technology, biological understanding, epidemiology and evolutionary analysis can help sustain existing therapies, anticipate the emergence of resistance or optimize the deployment of new therapies. PMID:27572976
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.
Advancing RF pulse design using an open-competition format: Report from the 2015 ISMRM challenge.
Grissom, William A; Setsompop, Kawin; Hurley, Samuel A; Tsao, Jeffrey; Velikina, Julia V; Samsonov, Alexey A
2017-10-01
To advance the best solutions to two important RF pulse design problems with an open head-to-head competition. Two sub-challenges were formulated in which contestants competed to design the shortest simultaneous multislice (SMS) refocusing pulses and slice-selective parallel transmission (pTx) excitation pulses, subject to realistic hardware and safety constraints. Short refocusing pulses are needed for spin echo SMS imaging at high multiband factors, and short slice-selective pTx pulses are needed for multislice imaging in ultra-high field MRI. Each sub-challenge comprised two phases, in which the first phase posed problems with a low barrier of entry, and the second phase encouraged solutions that performed well in general. The Challenge ran from October 2015 to May 2016. The pTx Challenge winners developed a spokes pulse design method that combined variable-rate selective excitation with an efficient method to enforce SAR constraints, which achieved 10.6 times shorter pulse durations than conventional approaches. The SMS Challenge winners developed a time-optimal control multiband pulse design algorithm that achieved 5.1 times shorter pulse durations than conventional approaches. The Challenge led to rapid step improvements in solutions to significant problems in RF excitation for SMS imaging and ultra-high field MRI. Magn Reson Med 78:1352-1361, 2017. © 2016 International Society for Magnetic Resonance in Medicine. © 2016 International Society for Magnetic Resonance in Medicine.
High Voltage Hybrid Electric Propulsion - Multilayered Functional Insulation System (MFIS) NASA-GRC
NASA Technical Reports Server (NTRS)
Lizcano, M.
2017-01-01
High power transmission cables pose a key challenge in future Hybrid Electric Propulsion Aircraft. The challenge arises in developing safe transmission lines that can withstand the unique environment found in aircraft while providing megawatts of power. High voltage AC, variable frequency cables do not currently exist and present particular electrical insulation challenges since electrical arcing and high heating are more prevalent at higher voltages and frequencies. Identifying and developing materials that maintain their dielectric properties at high voltage and frequencies is crucial.
Applying health economics for policy decision making: do devices differ from drugs?
Sorenson, Corinna; Tarricone, Rosanna; Siebert, Markus; Drummond, Michael
2011-05-01
Medical devices pose unique challenges for economic evaluation and associated decision-making processes that differ from pharmaceuticals. We highlight and discuss these challenges in the context of cardiac device therapy, based on a systematic review of relevant economic evaluations. Key challenges include practical difficulties in conducting randomized clinical trials, allowing for a 'learning curve' and user characteristics, accounting for the wider organizational impacts of introducing new devices, and allowing for variations in product characteristics and prices over time.
2011-10-03
Team Lead Jack Langelaan poses for a photograph next to the Pipistrel-USA, Taurus G4, aircraft prior to winning the 2011 Green Flight Challenge, sponsored by Google, on Monday, Oct. 3, 2011 at the NASA Ames Research Center, Mountain View, Calif. The all electric Taurus G4 aircraft achieved the equivalency of more than 400 miles per gallon. NASA and CAFE held the challenge to advance technologies in fuel efficiency and reduced emissions with cleaner renewable fuels and electric aircraft. Photo Credit: (NASA/Bill Ingalls)
NASA Technical Reports Server (NTRS)
Zhang. W. W.; Biskach, M. P.; Blake, P. N.; Chan, K. W.; Gaskin, J. A.; Hong, M. L.; Jones, W. D.; Kolos, L. D.; Mazzarella, J. R.; McClelland, R. S.;
2012-01-01
X-ray astronomy depends on the availability of telescopes with high resolution and large photon collecting areas. Since x-ray observation can only be carried out above the atmosphere, these telescopes must be necessarily lightweight. Compounding the lightweight requirement is that an x-ray telescope consists of many nested concentric shells, which further require that x-ray mirrors must also be geometrically thin to achieve high packing efficiency. This double lightweight and geometrically thin requirement poses significant technical challenges in fabricating the mirrors and in integrating them into mirror assemblies. This paper reports on the approach, strategy and status of our x-ray optics development program whose objective is to meet these technical challenges at modest cost to enable future x-ray missions, including small Explorer missions in the near term, probe class missions in the medium term, and large flagship missions in the long term.
Science, technology, and application of THz air photonics
NASA Astrophysics Data System (ADS)
Lu, X. F.; Clough, B.; Ho, I.-C.; Kaur, G.; Liu, J.; Karpowicz, N.; Dai, J. M.; Zhang, X.-C.
2010-11-01
The significant scientific and technological potential of terahertz (THz) wave sensing and imaging has been attracted considerable attention within many fields of research. However, the development of remote, broadband THz wave sensing technology is lagging behind the compelling needs that exist in the areas of astronomy, global environmental monitoring, and homeland security. This is due to the challenge posed by high absorption of ambient moisture in the THz range. Although various time-domain THz detection techniques have recently been demonstrated, the requirement for an on-site bias or forward collection of the optical signal inevitably prohibits their applications for remote sensing. The objective of this paper is to report updated THz air-plasma technology to meet this great challenge of remote sensing. A focused optical pulse (mJ pulse energy and femtosecond pulse duration) in gas creates a plasma, which can serve to generate intense, broadband, and directional THz waves in the far field.
Challenges in treating post-traumatic stress disorder and attachment trauma.
Allen, Jon G
2003-06-01
Treating women suffering from trauma poses significant challenges. The diagnostic prototype of post-traumatic stress disorder (PTSD) is based on single-event trauma, such as sexual assault in adulthood. Several effective cognitive- behavioral treatments for such traumas have been developed, although many treated patients continue to experience residual symptoms. Even more problematic is the complex developmental psychopathology stemming from a lifetime history of multiple traumas, often beginning with maltreatment in early attachment relationships. A history of attachment trauma undermines the development of capacities to regulate emotional distress and thereby complicates the treatment of acute trauma in adulthood. Such complex trauma requires a multifaceted treatment approach that must balance processing of traumatic memories with strategies to contain the intense emotions this processing evokes. Moreover, conducting such treatment places therapists at risk for secondary trauma such that trauma therapists also must process this stressful experience and implement strategies to regulate their own distress.
The challenge of instinctive behaviour and Darwin's theory of evolution.
Gordillo-García, Alejandro
2016-03-01
In the Origin of Species (1859), Darwin argued that his revolutionary theory of evolution by natural selection represented a significant breakthrough in the understanding of instinctive behaviour. However, many aspects in the development of his thinking on behavioural phenomena indicate that the explanation of this particular organic feature was by no means an easy one, but that it posed an authentic challenge - something that Darwin himself always recognized. This paper explores Darwin's treatment of instincts within his theory of natural selection. Particular attention is given to elucidate how he tackled the difficulties of explaining instincts as evolving mental features. He had to explain and demonstrate its inheritance, variation, and gradual accumulation within populations. The historical and philosophical aspects of his theory are highlighted, as well as his study of the case in which the explanation of instincts represented a 'special difficulty'; that is, the sterile castes of social insects. Copyright © 2016 Elsevier Ltd. All rights reserved.
Noise Reduction Potential of Large, Over-the-Wing Mounted, Advanced Turbofan Engines
NASA Technical Reports Server (NTRS)
Berton, Jeffrey J.
2000-01-01
As we look to the future, increasingly stringent civilian aviation noise regulations will require the design and manufacture of extremely quiet commercial aircraft. Indeed, the noise goal for NASA's Aeronautics Enterprise calls for technologies that will help to provide a 20 EPNdB reduction relative to today's levels by the year 2022. Further, the large fan diameters of modem, increasingly higher bypass ratio engines pose a significant packaging and aircraft installation challenge. One design approach that addresses both of these challenges is to mount the engines above the wing. In addition to allowing the performance trend towards large, ultra high bypass ratio cycles to continue, this over-the-wing design is believed to offer noise shielding benefits to observers on the ground. This paper describes the analytical certification noise predictions of a notional, long haul, commercial quadjet transport with advanced, high bypass engines mounted above the wing.
Reliability of Travel Time: Challenges Posed by a Multimodal Transport Participation
NASA Astrophysics Data System (ADS)
Wanjek, Monika; Hauger, Georg
2017-10-01
Travel time reliability represents an essential component in individual decision making processes for transport participants, particularly regarding mode choices. As criteria that describe the quality of both transportation systems and transportation modes, travel time reliability is already frequently compiled, analysed and quoted as an argument. Currently, travel time reliability is solely mentioned on monomodal trips, while it has remained unconsidered on multimodal transport participation. Given the fact that multimodality gained significantly in importance, it is crucial to discuss how travel time reliability could be determined on multimodal trips. This paper points out the challenges that occur for applying travel time reliability on multimodal transport participation. Therefore, examples will be given within this paper. In order to illustrate theoretical ideas, trips and influencing factors that could be expected within the everyday transport behaviour of commuters in a (sub)urban area will be described.
Messing, Russell H.
2012-01-01
In August 2010 the coffee berry borer, Hypothenemus hampei, was first reported to have invaded the Kona coffee growing region of Hawaii, posing a severe economic challenge to the fourth largest agricultural commodity in the State. Despite its long and widespread occurrence throughout the tropics as the most serious pest of coffee, there are still discrepancies in the literature regarding several basic aspects of berry borer biology relevant to its control. In Kona coffee plantations, we investigated the beetles’ response to several trap and lure formulations, and examined the occurrence of beetles in seeds of alternate host plants occurring adjacent to coffee farms. While traps were shown to capture significant numbers of beetles per day, and the occurrence of beetles in alternate hosts was quite rare, the unique situation of coffee culture in Hawaii will make this pest extremely challenging to manage in the Islands. PMID:26466620
Katende, Godfrey; Donnelly, Mary
2016-05-01
In terms of disease burden, many low- and middle-income countries are currently experiencing a transition from infectious to chronic diseases. In Uganda, non-communicable diseases (NCDs) have increased significantly in recent years; this challenge is compounded by the healthcare worker shortage and the underfunded health system administration. Addressing the growing prevalence of NCDs requires evidence-based policies and strategies to reduce morbidity and mortality rates; however, the integration and evaluation of new policies and processes pose many challenges. Task-shifting is the process whereby specific tasks are transferred to health workers with less training and fewer qualifications. Successful implementation of a task-shifting policy requires appropriate skill training, clearly defined roles, adequate evaluation, an enhanced training capacity and sufficient health worker incentives. This article focuses on task-shifting policy as a potentially effective strategy to address the growing burden of NCDs on the Ugandan healthcare system.
Mitochondrial disorders: Challenges in diagnosis & treatment
Khan, Nahid Akhtar; Govindaraj, Periyasamy; Meena, Angamuthu Kannan; Thangaraj, Kumarasamy
2015-01-01
Mitochondrial dysfunctions are known to be responsible for a number of heterogenous clinical presentations with multi-systemic involvement. Impaired oxidative phosphorylation leading to a decrease in cellular energy (ATP) production is the most important cause underlying these disorders. Despite significant progress made in the field of mitochondrial medicine during the last two decades, the molecular mechanisms underlying these disorders are not fully understood. Since the identification of first mitochondrial DNA (mtDNA) mutation in 1988, there has been an exponential rise in the identification of mtDNA and nuclear DNA mutations that are responsible for mitochondrial dysfunction and disease. Genetic complexity together with ever widening clinical spectrum associated with mitochondrial dysfunction poses a major challenge in diagnosis and treatment. Effective therapy has remained elusive till date and is mostly efficient in relieving symptoms. In this review, we discuss the important clinical and genetic features of mitochondrials disorders with special emphasis on diagnosis and treatment. PMID:25857492
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.
Exotic encounters with dental implants: managing complications with unidentified systems.
Mattheos, N; Janda, M Schittek
2012-06-01
As the application of dental implants increases worldwide, so is the number of technical and biological complications that general dental practitioners will be called to manage, while maintaining implant patients. In addition, the greater patient mobility encountered today combined with a growing trend of 'dental implant tourism' will very often result in situations where the dentist is requested to deal with complications in implants placed elsewhere and which sometimes might be of an 'exotic' system one cannot directly recognize. Such a situation can pose significant challenges to even experienced clinicians. The challenges are not only in the scientific field, but often include professional and ethical implications. This case report will discuss strategies for the management of implant complications in cases of unidentified implant systems. Critical factors in such situations would be the clinician's experience and special training, the correct radiographic technique, as well as access to the appropriate tools and devices. © 2012 Australian Dental Association.
Adapting to the health impacts of climate change in a sustainable manner.
Hoy, Damian; Roth, Adam; Lepers, Christelle; Durham, Jo; Bell, Johann; Durand, Alexis; Lal, Padma Narsey; Souares, Yvan
2014-12-11
The climate is changing and this poses significant threats to human health. Climate change is one of the greatest challenges facing Pacific Island countries and territories due to their unique geophysical features, and their social, economic and cultural characteristics. The Pacific region also faces challenges with widely dispersed populations, limited resources and fragmented health systems. Over the past few years, there has been a substantial increase in international aid for health activities aimed at adapting to the threats of climate change. This funding needs to be used strategically to ensure an effective approach to reducing the health risk from climate change. Respecting the principles of development effectiveness will result in more effective and sustainable adaptation, in particular, 1) processes should be owned and driven by local communities, 2) investments should be aligned with existing national priorities and policies, and 3) existing systems must not be ignored, but rather expanded upon and reinforced.
Recent improvements in oily wastewater treatment: Progress, challenges, and future opportunities.
Jamaly, Sanaa; Giwa, Adewale; Hasan, Shadi Wajih
2015-11-01
Oily wastewater poses significant threats to the soil, water, air and human beings because of the hazardous nature of its oil contents. The objective of this review paper is to highlight the current and recently developed methods for oily wastewater treatment through which contaminants such as oil, fats, grease, and inorganics can be removed for safe applications. These include electrochemical treatment, membrane filtration, biological treatment, hybrid technologies, use of biosurfactants, treatment via vacuum ultraviolet radiation, and destabilization of emulsions through the use of zeolites and other natural minerals. This review encompasses innovative and novel approaches to oily wastewater treatment and provides scientific background for future work that will be aimed at reducing the adverse impact of the discharge of oily wastewater into the environment. The current challenges affecting the optimal performance of oily wastewater treatment methods and opportunities for future research development in this field are also discussed. Copyright © 2015. Published by Elsevier B.V.
Parenting teens with attention-deficit/hyperactivity disorder: challenges and opportunities.
Modesto-Lowe, Vania; Chaplin, Margaret; Godsay, Viraj; Soovajian, Victoria
2014-09-01
Attention-deficit/hyperactivity disorder (ADHD) presents in childhood with inattention, hyperactivity, and impulsivity and is associated with functional impairments. These children tend to display a variety of disruptive behaviors, which may worsen in adolescence. Teens with ADHD may show high levels of defiance, posing significant challenges for parents. Early efforts to understand parenting in the context of teen ADHD reveal high levels of parental stress and reactivity in response to the teen's ADHD symptoms. Subsequent research recognized that some of these parents have ADHD or other psychopathology that may contribute to maladaptive parenting. However, some parents adjust and demonstrate optimism and resilience in the face of their teens' ADHD. Recent research has identified parental factors (eg, emotional intelligence) and interventions (eg, mindfulness training) that may improve parenting/teen relationships and the developmental outcomes of teens. This article explores parenting teens with ADHD with a focus on these novel interventions. © The Author(s) 2014.
Trojan Horse Antibiotics—A Novel Way to Circumvent Gram-Negative Bacterial Resistance?
Tillotson, Glenn S.
2016-01-01
Antibiotic resistance has been emerged as a major global health problem. In particular, gram-negative species pose a significant clinical challenge as bacteria develop or acquire more resistance mechanisms. Often, these bacteria possess multiple resistance mechanisms, thus nullifying most of the major classes of drugs. Novel approaches to this issue are urgently required. However, the challenges of developing new agents are immense. Introducing novel agents is fraught with hurdles, thus adapting known antibiotic classes by altering their chemical structure could be a way forward. A chemical addition to existing antibiotics known as a siderophore could be a solution to the gram-negative resistance issue. Siderophore molecules rely on the bacterial innate need for iron ions and thus can utilize a Trojan Horse approach to gain access to the bacterial cell. The current approaches to using this potential method are reviewed. PMID:27773991
Trojan Horse Antibiotics-A Novel Way to Circumvent Gram-Negative Bacterial Resistance?
Tillotson, Glenn S
2016-01-01
Antibiotic resistance has been emerged as a major global health problem. In particular, gram-negative species pose a significant clinical challenge as bacteria develop or acquire more resistance mechanisms. Often, these bacteria possess multiple resistance mechanisms, thus nullifying most of the major classes of drugs. Novel approaches to this issue are urgently required. However, the challenges of developing new agents are immense. Introducing novel agents is fraught with hurdles, thus adapting known antibiotic classes by altering their chemical structure could be a way forward. A chemical addition to existing antibiotics known as a siderophore could be a solution to the gram-negative resistance issue. Siderophore molecules rely on the bacterial innate need for iron ions and thus can utilize a Trojan Horse approach to gain access to the bacterial cell. The current approaches to using this potential method are reviewed.
Deep Space Control Challenges of the New Millennium
NASA Technical Reports Server (NTRS)
Bayard, David S.; Burdick, Garry M.
1999-01-01
The exploration of deep space presents a variety of significant control challenges. Long communication delays coupled with challenging new science objectives require high levels of system autonomy and increasingly demanding pointing and control capabilities. Historically, missions based on the use of a large single spacecraft have been successful and popular since the early days of NASA. However, these large spacecraft missions are currently being displaced by more frequent and more focused missions based on the use of smaller and less expensive spacecraft designs. This trend drives the need to design smart software and good algorithms which together with the miniaturization of control components will improve performance while replacing the heavier and more expensive hardware used in the past. NASA's future space exploration will also include mission types that have never been attempted before, posing significant challenges to the underlying control system. This includes controlled landing on small bodies (e.g., asteroids and comets), sample return missions (where samples are brought back from other planets), robotic exploration of planetary surfaces (e.g., intelligent rovers), high precision formation flying, and deep space optical interferometry, While the control of planetary spacecraft for traditional flyby and orbiter missions are based on well-understood methodologies, control approaches for many future missions will be fundamentally different. This paradigm shift will require completely new control system development approaches, system architectures, and much greater levels of system autonomy to meet expected performance in the presence of significant environmental disturbances, and plant uncertainties. This paper will trace the motivation for these changes and will layout the approach taken to meet the new challenges. Emerging missions will be used to explain and illustrate the need for these changes.
Do, Minh T.; Fréchette, Mylène; McFaull, Steven; Denning, Bryany; Ruta, Mike; Thompson, Wendy
2013-01-01
Background Injury is a major public health concern, particularly for Canadians living in Arctic regions where the harsh physical and social conditions pose additional challenges. Surveillance data collected over the past 2 decades through the Canadian Hospitals Injury Reporting and Prevention Program (CHIRPP) provide insights into the burden of injuries in certain parts of Canada. Objectives This study aims to summarize and compare patterns of injuries in the Northwest Territories (NWT) and Nunavut to other southern communities across Canada. Methods Analysis was based on CHIRPP data covering the period 1991–2010. Proportionate injury ratio (PIR) and its 95% confidence interval were used to summarize and compare the injury experience of Canadians living in the Arctic regions to other CHIRPP sites across Canada. Results Between 1991 and 2010, there were 65,116 reported injuries. Approximately 83% of the cases were unintentional in nature; however, significantly higher proportions were observed for assaults and maltreatment (PIR=2.80, 95% CI: 2.72–2.88) among Canadians living in northern communities. Significantly higher proportions were also observed for crushing/amputations (PIR=2.28, 95% CI: 2.14–2.44), poison/toxic effects (PIR=1.21, 95% CI: 1.15–1.28), drowning/asphyxiations (PIR=1.52, 95% CI: 1.33–1.74) and frostbites (PIR=7.39, 95% CI: 6.60–8.28). The use of all-terrain vehicles or snowmobiles also resulted in significantly higher proportions of injuries (PIR=1.93, 95% CI: 1.79–2.09). Conclusions This study contributes to the limited literature describing injuries in northern communities where the harsh physical and social climates pose additional challenges. Excesses in the proportions identified in this study could be useful in identifying strategies needed to minimize injury risks in northern communities within Canada. PMID:24062994
Virus diseases of farmed shrimp in the Western Hemisphere (the Americas): a review.
Lightner, D V
2011-01-01
Penaeid shrimp aquaculture is an important industry in the Americas, and the industry is based almost entirely on the culture of the Pacific White Shrimp, Litopenaeus vannamei. Western Hemisphere shrimp farmers in 14 countries in 2004 produced more than 200,000 metric tons of shrimp, generated more than $2 billion in revenue, and employed more than 500,000 people. Disease has had a major impact on shrimp aquaculture in the Americas since it became a significant commercial entity in the 1970s. Diseases due to viruses, rickettsial-like bacteria, true bacteria, protozoa, and fungi have emerged as major diseases of farmed shrimp in the region. Many of the bacterial, fungal and protozoan caused diseases are managed using improved culture practices, routine sanitation, and the use of chemotherapeutics. However, the virus diseases have been far more problematic to manage and they have been responsible for the most costly epizootics. Examples include the Taura syndrome pandemic that began in 1991-1992 when the disease emerged in Ecuador, and the subsequent White Spot Disease pandemic that followed its introduction to Central America from Asia in 1999. Because of their socioeconomic significance to shrimp farming, seven of the nine crustacean diseases listed by the World Animal Organization (OIE) are virus diseases of shrimp. Of the seven virus diseases of penaeid shrimp, five are native to the Americas or have become enzootic following their introduction. The shrimp virus diseases in the Americas are increasingly being managed by exclusion using a combination of biosecurity and the practice of culturing domesticated specific pathogen-free (SPF) stocks or specific pathogen-resistant (SPR) stocks. Despite the significant challenges posed by disease, the shrimp farming industry of the Americas has responded to the challenges posed by disease and it has developed methods to manage its diseases and mature into a sustainable industry. Copyright © 2010 Elsevier Inc. All rights reserved.
Strecker, Claas; Meyer, Bernd
2018-05-29
Protein flexibility poses a major challenge to docking of potential ligands in that the binding site can adopt different shapes. Docking algorithms usually keep the protein rigid and only allow the ligand to be treated as flexible. However, a wrong assessment of the shape of the binding pocket can prevent a ligand from adapting a correct pose. Ensemble docking is a simple yet promising method to solve this problem: Ligands are docked into multiple structures, and the results are subsequently merged. Selection of protein structures is a significant factor for this approach. In this work we perform a comprehensive and comparative study evaluating the impact of structure selection on ensemble docking. We perform ensemble docking with several crystal structures and with structures derived from molecular dynamics simulations of renin, an attractive target for antihypertensive drugs. Here, 500 ns of MD simulations revealed binding site shapes not found in any available crystal structure. We evaluate the importance of structure selection for ensemble docking by comparing binding pose prediction, ability to rank actives above nonactives (screening utility), and scoring accuracy. As a result, for ensemble definition k-means clustering appears to be better suited than hierarchical clustering with average linkage. The best performing ensemble consists of four crystal structures and is able to reproduce the native ligand poses better than any individual crystal structure. Moreover this ensemble outperforms 88% of all individual crystal structures in terms of screening utility as well as scoring accuracy. Similarly, ensembles of MD-derived structures perform on average better than 75% of any individual crystal structure in terms of scoring accuracy at all inspected ensembles sizes.
Development of Trivia Game for speech understanding in background noise.
Schwartz, Kathryn; Ringleb, Stacie I; Sandberg, Hilary; Raymer, Anastasia; Watson, Ginger S
2015-01-01
Listening in noise is an everyday activity and poses a challenge for many people. To improve the ability to understand speech in noise, a computerized auditory rehabilitation game was developed. In Trivia Game players are challenged to answer trivia questions spoken aloud. As players progress through the game, the level of background noise increases. A study using Trivia Game was conducted as a proof-of-concept investigation in healthy participants. College students with normal hearing were randomly assigned to a control (n = 13) or a treatment (n = 14) group. Treatment participants played Trivia Game 12 times over a 4-week period. All participants completed objective (auditory-only and audiovisual formats) and subjective listening in noise measures at baseline and 4 weeks later. There were no statistical differences between the groups at baseline. At post-test, the treatment group significantly improved their overall speech understanding in noise in the audiovisual condition and reported significant benefits in their functional listening abilities. Playing Trivia Game improved speech understanding in noise in healthy listeners. Significant findings for the audiovisual condition suggest that participants improved face-reading abilities. Trivia Game may be a platform for investigating changes in speech understanding in individuals with sensory, linguistic and cognitive impairments.
Thin Film Heat Flux Sensor Development for Ceramic Matrix Composite (CMC) Systems
NASA Technical Reports Server (NTRS)
Wrbanek, John D.; Fralick, Gustave C.; Hunter, Gary W.; Zhu, Dongming; Laster, Kimala L.; Gonzalez, Jose M.; Gregory, Otto J.
2010-01-01
The NASA Glenn Research Center (GRC) has an on-going effort for developing high temperature thin film sensors for advanced turbine engine components. Stable, high temperature thin film ceramic thermocouples have been demonstrated in the lab, and novel methods of fabricating sensors have been developed. To fabricate thin film heat flux sensors for Ceramic Matrix Composite (CMC) systems, the rough and porous nature of the CMC system posed a significant challenge for patterning the fine features required. The status of the effort to develop thin film heat flux sensors specifically for use on silicon carbide (SiC) CMC systems with these new technologies is described.
Naik, B.; Guddemane, D. K.; Bhat, P.; Wilson, N.; Sreenivas, A. N.; Lauritsen, J. M.; Rieder, H. L.
2013-01-01
Ensuring quality of data during electronic data capture has been one of the most neglected components of operational research. Multicentre studies are also challenged with issues about logistics of travel, training, supervision, monitoring and troubleshooting support. Allocating resources to these issues can pose a significant bottleneck for operational research in resource-limited settings. In this article, we describe an innovative and efficient way of coordinating data capture in multicentre operational research using a combination of three open access technologies—EpiData for data capture, Dropbox for sharing files and TeamViewer for providing remote support. PMID:26392997
Analysis of the physiotherapy industry: challenges for marketing.
Sheppard, L
1996-01-01
The physiotherapy industry can be analysed using Porter's (1979) five forces. Physiotherapy uses medical, geographic and funding segmentation. The power of the buyers in these segments is considerable. Substitutes are posing a threat to physiotherapy with few barriers to entry to operate in the health care environment. The suppliers, particularly doctors, have significant power in referring clients. Competitive rivalry for these clients can exist between individual physiotherapists and multi-disciplinary clinics. The difference in orientation of private and public physiotherapy can also be a basis for rivalry. Repositioning to view the client as both the supplier and recipients enables the physiotherapy industry to gain competitive advantage and ensures long term growth.
Novel EO/IR sensor technologies
NASA Astrophysics Data System (ADS)
Lewis, Keith
2011-10-01
The requirements for advanced EO/IR sensor technologies are discussed in the context of evolving military operations, with significant emphasis on the development of new sensing technologies to meet the challenges posed by asymmetric threats. The Electro-Magnetic Remote Sensing (EMRS DTC) was established in 2003 to provide a centre of excellence in sensor research and development, supporting new capabilities in key military areas such as precision attack, battlespace manoeuvre and information superiority. In the area of advanced electro-optic technology, the DTC has supported work on discriminative imaging, advanced detectors, laser components/technologies, and novel optical techniques. This paper provides a summary of some of the EO/IR technologies explored by the DTC.
Modern steels at atomic and nanometre scales
Caballero, F. G.; Garcia-Mateo, C.; Miller, M. K.
2014-10-10
Processing bulk nanocrystalline materials for structural applications still poses a difficult challenge, particularly in achieving an industrially viable process. Recent work in ferritic steels has proved that it is possible to move from ultrafine to nanoscale by exploiting the bainite reaction without the use of severe deformation, rapid heat treatment or mechanical processing. This new generation of steels has been designed in which transformation at low temperature leads to a nanoscale structure consisting of extremely fine, 20–40 nm thick plates of bainitic ferrite and films of retained austenite. Finally, a description of the characteristics and significance of this remarkable microstructuremore » is provided here.« less
New insights into the Kawah Ijen hydrothermal system from geophysical data
Caudron, Corentin; Mauri, G.; Williams-Jones, Glyn; Lecocq, Thomas; Syahbana, Devy Kamil; de Plaen, Raphael; Peiffer, Loic; Bernard, Alain; Saracco, Ginette
2017-01-01
Volcanoes with crater lakes and/or extensive hydrothermal systems pose significant challenges with respect to monitoring and forecasting eruptions, but they also provide new opportunities to enhance our understanding of magmatic–hydrothermal processes. Their lakes and hydrothermal systems serve as reservoirs for magmatic heat and fluid emissions, filtering and delaying the surface expressions of magmatic unrest and eruption, yet they also enable sampling and monitoring of geochemical tracers. Here, we describe the outcomes of a highly focused international experimental campaign and workshop carried out at Kawah Ijen volcano, Indonesia, in September 2014, designed to answer fundamental questions about how to improve monitoring and eruption forecasting at wet volcanoes.
Active mixing of complex fluids at the microscale
Ober, Thomas J.; Foresti, Daniele; Lewis, Jennifer A.
2015-09-22
Mixing of complex fluids at low Reynolds number is fundamental for a broad range of applications, including materials assembly, microfluidics, and biomedical devices. Of these materials, yield stress fluids (and gels) pose the most significant challenges, especially when they must be mixed in low volumes over short timescales. New scaling relationships between mixer dimensions and operating conditions are derived and experimentally verified to create a framework for designing active microfluidic mixers that can efficiently homogenize a wide range of complex fluids. As a result, active mixing printheads are then designed and implemented for multimaterial 3D printing of viscoelastic inks withmore » programmable control of local composition.« less
Assessing Spontaneous Combustion Instability with Recurrence Quantification Analysis
NASA Technical Reports Server (NTRS)
Eberhart, Chad J.; Casiano, Matthew J.
2016-01-01
Spontaneous instabilities can pose a significant challenge to verification of combustion stability, and characterizing its onset is an important avenue of improvement for stability assessments of liquid propellant rocket engines. Recurrence Quantification Analysis (RQA) is used here to explore nonlinear combustion dynamics that might give insight into instability. Multiple types of patterns representative of different dynamical states are identified within fluctuating chamber pressure data, and markers for impending instability are found. A class of metrics which describe these patterns is also calculated. RQA metrics are compared with and interpreted against another metric from nonlinear time series analysis, the Hurst exponent, to help better distinguish between stable and unstable operation.
Bidirectional peripheral nerve interface and applications.
Thakor, Nitish V; Qihong Wang; Greenwald, Elliot
2016-08-01
Peripheral nerves, due to their small size and complex innervation to organs and complex physiology, pose particularly significant challenges towards interfacing electrodes and electronics to enable neuromodulation. Here, we present a review of the technology for building such interface, including recording and stimulating electrodes and low power electronics, as well as powering. Of particular advantage to building a miniature implanted device is a "bidirectional" system that both senses from the nerves or surrogate organs and stimulates the nerves to affect the organ function. This review and presentation will cover a range of electrodes, electronics, wireless power and data schemes and system integration, and will end with some examples and applications.
Heath, Jessica L.; Yin, Dwight E.; Wechsler, Daniel S.; Turner, David A.
2015-01-01
Disseminated cryptococcal infection is rarely reported in the setting of pediatric acute leukemia, despite the immunocompromised state of these patients. However, when present, disseminated cryptococcal infection poses treatment challenges and is associated with significant morbidity and mortality. Treatment of invasive fungal disease in a child with acute leukemia requires a delicate balance between anti-fungal and anti-neoplastic therapy. This balance is particularly important early in the course of leukemia, since both the underlying disease and overwhelming infection can be life threatening. We describe the successful management of life-threatening disseminated cryptococcosis in a child with acute lymphoblastic leukemia during induction therapy. PMID:22258349
Pronounced impairment of everyday skills and self-care in posterior cortical atrophy.
Shakespeare, Timothy J; Yong, Keir X X; Foxe, David; Hodges, John; Crutch, Sebastian J
2015-01-01
Posterior cortical atrophy (PCA) is a neurodegenerative syndrome characterized by progressive visual dysfunction and parietal, occipital, and occipitotemporal atrophy. The aim of this study was to compare the impact of PCA and typical Alzheimer's disease (tAD) on everyday functional abilities and neuropsychiatric status. The Cambridge Behavioural Inventory-Revised was given to carers of 32 PCA and 71 tAD patients. PCA patients showed significantly greater impairment in everyday skills and self-care while the tAD group showed greater impairment in aspects of memory and orientation, and motivation. We suggest that PCA poses specific challenges for those caring for people affected by the condition.
Gafoor, Sameer; Petrescu, O Madalina; Lehr, Eric J; Puls, Charles; Zhang, Ming; Petersen, John L; Olsen, John V; Penev, Irina; Agrawal, Mayank; Sharma, Rahul; Barnhart, Glenn
2017-03-01
Patients who present with both severe mitral and tricuspid regurgitation who are symptomatic despite optimal medical therapy and at prohibitive risk for surgery pose a significant therapeutic challenge. The MitraClip device (Abbott Vascular) is approved for percutaneous mitral valve repair in high-risk and non-operative patients, and has also been used for tricuspid valve repair. Imaging support for percutaneous edge-to-edge tricuspid valve repair has not been reported and is a vital part of the procedure. Here, we present a periprocedural imaging strategy for percutaneous tricuspid valve repair with the MitraClip device using a bicuspidization technique.
Diet, exercise, behavior: the promise and limits of lifestyle change.
Bennett, Brian; Sothern, Melinda S
2009-08-01
The prevalent surge in childhood and adolescent obesity within the past 3 decades poses a significant challenge for many pediatric clinicians who are charged with treating this condition. Comprehensive, research-based pediatric obesity treatment programs are essential to addressing this problem and preventing the transition of obesity and its many comorbidities into adulthood. This paper will identify dietary, physical activity, and behavioral approaches to lifestyle change and describe how they are incorporated as part of multidisciplinary treatment interventions in youth. Specific tailoring of treatment programs to address age and varying degrees of overweight and obesity will also be presented along with recommendations for future research.
Vemuri, Anant Suraj; Nicolau, Stephane A; Ayache, Nicholas; Marescaux, Jacques; Soler, Luc
2013-01-01
The screening of oesophageal adenocarcinoma involves obtaining biopsies at different regions along the oesophagus. The localization and tracking of these biopsy sites inter-operatively poses a significant challenge for providing targeted treatments. This paper presents a novel framework for providing a guided navigation to the gastro-intestinal specialist for accurate re-positioning of the endoscope at previously targeted sites. Firstly, we explain our approach for the application of electromagnetic tracking in acheiving this objective. Then, we show on three in-vivo porcine interventions that our system can provide accurate guidance information, which was qualitatively evaluated by five experts.
Active mixing of complex fluids at the microscale
Ober, Thomas J.; Foresti, Daniele; Lewis, Jennifer A.
2015-01-01
Mixing of complex fluids at low Reynolds number is fundamental for a broad range of applications, including materials assembly, microfluidics, and biomedical devices. Of these materials, yield stress fluids (and gels) pose the most significant challenges, especially when they must be mixed in low volumes over short timescales. New scaling relationships between mixer dimensions and operating conditions are derived and experimentally verified to create a framework for designing active microfluidic mixers that can efficiently homogenize a wide range of complex fluids. Active mixing printheads are then designed and implemented for multimaterial 3D printing of viscoelastic inks with programmable control of local composition. PMID:26396254
HSA, hospital planning: arena of conflict offers room for cooperation.
Pierce, C F
1980-03-16
HSAs and hospitals have conflicting approaches and outcomes to planning, but hospitals can and should respond individually and collectively to challenges posed by HSAs' planning as well as to opportunities for constructive cooperation.
ERIC Educational Resources Information Center
Geber, Beverly
1995-01-01
The national skill standards project may take 10 years to complete and will be expensive to set up and maintain. Getting consensus from industry, unions, and educators and ensuring checks for fairness and nondiscrimination pose challenges. (SK)
Infusing and selecting V&V activities
NASA Technical Reports Server (NTRS)
Feather, M. S.
2002-01-01
The evolving nature of software development poses a continuing series of challenges for V&V. In response, the V&V community selectively adapts the use of existing V&V activities, and introduces new and improved ones.
Multiperson visual focus of attention from head pose and meeting contextual cues.
Ba, Sileye O; Odobez, Jean-Marc
2011-01-01
This paper introduces a novel contextual model for the recognition of people's visual focus of attention (VFOA) in meetings from audio-visual perceptual cues. More specifically, instead of independently recognizing the VFOA of each meeting participant from his own head pose, we propose to jointly recognize the participants' visual attention in order to introduce context-dependent interaction models that relate to group activity and the social dynamics of communication. Meeting contextual information is represented by the location of people, conversational events identifying floor holding patterns, and a presentation activity variable. By modeling the interactions between the different contexts and their combined and sometimes contradictory impact on the gazing behavior, our model allows us to handle VFOA recognition in difficult task-based meetings involving artifacts, presentations, and moving people. We validated our model through rigorous evaluation on a publicly available and challenging data set of 12 real meetings (5 hours of data). The results demonstrated that the integration of the presentation and conversation dynamical context using our model can lead to significant performance improvements.
Pitting corrosion as a mixed system: coupled deterministic-probabilistic simulation of pit growth
NASA Astrophysics Data System (ADS)
Ibrahim, Israr B. M.; Fonna, S.; Pidaparti, R.
2018-05-01
Stochastic behavior of pitting corrosion poses a unique challenge in its computational analysis. However, it also stems from electrochemical activity causing general corrosion. In this paper, a framework for corrosion pit growth simulation based on the coupling of the Cellular Automaton (CA) and Boundary Element Methods (BEM) is presented. The framework assumes that pitting corrosion is controlled by electrochemical activity inside the pit cavity. The BEM provides the prediction of electrochemical activity given the geometrical data and polarization curves, while the CA is used to simulate the evolution of pit shapes based on electrochemical activity provided by BEM. To demonstrate the methodology, a sample case of local corrosion cells formed in pitting corrosion with varied dimensions and polarization functions is considered. Results show certain shapes tend to grow in certain types of environments. Some pit shapes appear to pose a higher risk by being potentially significant stress raisers or potentially increasing the rate of corrosion under the surface. Furthermore, these pits are comparable to commonly observed pit shapes in general corrosion environments.
Accurate estimation of human body orientation from RGB-D sensors.
Liu, Wu; Zhang, Yongdong; Tang, Sheng; Tang, Jinhui; Hong, Richang; Li, Jintao
2013-10-01
Accurate estimation of human body orientation can significantly enhance the analysis of human behavior, which is a fundamental task in the field of computer vision. However, existing orientation estimation methods cannot handle the various body poses and appearances. In this paper, we propose an innovative RGB-D-based orientation estimation method to address these challenges. By utilizing the RGB-D information, which can be real time acquired by RGB-D sensors, our method is robust to cluttered environment, illumination change and partial occlusions. Specifically, efficient static and motion cue extraction methods are proposed based on the RGB-D superpixels to reduce the noise of depth data. Since it is hard to discriminate all the 360 (°) orientation using static cues or motion cues independently, we propose to utilize a dynamic Bayesian network system (DBNS) to effectively employ the complementary nature of both static and motion cues. In order to verify our proposed method, we build a RGB-D-based human body orientation dataset that covers a wide diversity of poses and appearances. Our intensive experimental evaluations on this dataset demonstrate the effectiveness and efficiency of the proposed method.
Challenges posed to the European pharmaceutical regulatory system by highly personalized medicines.
Johnston, John D; Feldschreiber, Peter
2014-03-01
The European pharmaceutical regulatory system has not yet been challenged by issues related to highly personalized medicines such as those to be found with active substances that affect RNA biochemistry. We review the current status of RNA-based pharmacology and present three possible case histories. The implications for the European pharmaceutical regulatory system are discussed. © 2013 The British Pharmacological Society.
Mortality data in the age of drones ‡.
Carruthers, Elspeth
2018-03-01
Mortality data plays an essential role in shaping humanitarian, legal and ethical responses to conflict situations. The rise of drone warfare poses new questions regarding the accuracy and reliability of mortality data in conflict. This article examines some of the methodological and political challenges to collecting mortality data in drone warfare, and how the way in which drones are framed in public discourse contributes to these challenges.
Changes in the Arctic: Background and Issues for Congress
2017-01-05
challenges to exploration. Additionally, any discovery of new oil and gas deposits far from existing storage, pipelines , and shipping facilities...Changes to the Arctic brought about by warming temperatures will likely allow more exploration for oil, gas , and minerals. Warming that causes...permafrost to melt could pose challenges to onshore exploration activities. Increased oil and gas exploration and tourism (cruise ships) in the Arctic
ERIC Educational Resources Information Center
Pallisera, Maria; Fullana, Judit; Puyaltó, Carol; Vilà, Montserrat
2016-01-01
The transition to adulthood poses one of the most complex challenges for young people with intellectual disabilities. In order to conduct a wide-reaching and in-depth study of this process, we need to know the views of these young people themselves and their families. This article presents research designed to collect the experiences and…
Infant feeding. 5. Managing baby related feeding challenges.
Marshall, Joyce
2013-02-01
'Infant feeding' is the 12th series of 'Midwifery basics' targeted at practising midwives. The aim of these articles is to inform and encourage readers to seek further information through a series of activities relating to the topic. In this fifth article Joyce Marshall considers a range of baby related issues that pose challenges for both mothers and midwives in relation to infant feeding.
ERIC Educational Resources Information Center
Learning Point Associates / North Central Regional Educational Laboratory (NCREL), 2005
2005-01-01
Literacy instruction does not end with reading success in early grades. As students move to middle and high school, new challenges emerge that can affect literacy achievement. Even for students who achieve early reading and writing success, the literacy demands of middle and high school can pose substantial challenges. Older students must be able…
Six Challenges for Ethical Conduct in Science.
Niemi, Petteri
2016-08-01
The realities of human agency and decision making pose serious challenges for research ethics. This article explores six major challenges that require more attention in the ethics education of students and scientists and in the research on ethical conduct in science. The first of them is the routinization of action, which makes the detection of ethical issues difficult. The social governance of action creates ethical problems related to power. The heuristic nature of human decision making implies the risk of ethical bias. The moral disengagement mechanisms represent a human tendency to evade personal responsibility. The greatest challenge of all might be the situational variation in people's ethical behaviour. Even minor situational factors have a surprisingly strong influence on our actions. Furthermore, finally, the nature of ethics itself also causes problems: instead of clear answers, we receive a multitude of theories and intuitions that may sometimes be contradictory. All these features of action and ethics represent significant risks for ethical conduct in science. I claim that they have to be managed within the everyday practices of science and addressed explicitly in research ethics education. I analyse them and suggest some ways in which their risks can be alleviated.
Tooth display and lip position during spontaneous and posed smiling in adults.
Van Der Geld, Pieter; Oosterveld, Paul; Berge, Stefaan J; Kuijpers-Jagtman, Anne M
2008-08-01
To analyze differences in tooth display, lip-line height, and smile width between the posed smiling record, traditionally produced for orthodontic diagnosis, and the spontaneous (Duchenne) smile of joy. The faces of 122 male participants were each filmed during spontaneous and posed smiling. Spontaneous smiles were elicited through the participants watching a comical movie. Maxillary and mandibular lip-line heights, tooth display, and smile width were measured using a digital videographic method for smile analysis. Paired sample t-tests were used to compare measurements of posed and spontaneous smiling. Maxillary lip-line heights during spontaneous smiling were significantly higher than during posed smiling. Compared to spontaneous smiling, tooth display in the (pre)molar area during posed smiling decreased by up to 30%, along with a significant reduction of smile width. During posed smiling, also mandibular lip-line heights changed and the teeth were more covered by the lower lip than during spontaneous smiling. Reduced lip-line heights, tooth display, and smile width on a posed smiling record can have implications for the diagnostics of lip-line height, smile arc, buccal corridors, and plane of occlusion. Spontaneous smiling records next to posed smiling records are therefore recommended for diagnostic purposes. Because of the dynamic nature of spontaneous smiling, it is proposed to switch to dynamic video recording of the smile.
Dr. David Brown poses with students at Ronald McNair Middle School
NASA Technical Reports Server (NTRS)
1999-01-01
Dr. David Brown (right), a NASA astronaut, poses with students in the gymnasium of Ronald McNair Magnet School in Cocoa, Fla. From left, the students are Kristin Rexford, Danitra Anderson, Dominique Smith, Fallon Davis, and Qiana Taylor. Brown was at the school to attend a tribute to NASA astronaut Ronald McNair. The school had previously been renamed for the fallen astronaut who was one of a crew of seven, who lost their lives during an accident following launch of the Space Shuttle Challenger in January 1986.
Ms. Rodriquez and Mickey Mouse pose with a portrait of Ronald McNair
NASA Technical Reports Server (NTRS)
1999-01-01
In the gymnasium of Ronald McNair Magnet School in Cocoa, Fla., Ms. Maria Rodriguez, an Walt Disney World Ambassador, and Mickey Mouse pose with a portrait of NASA astronaut Ronald McNair. The portrait was presented to the school by Walt Disney World during a tribute to McNair. The school had previously been renamed for the fallen astronaut, who was one of a crew of seven who lost their lives during an accident following launch of the Space Shuttle Challenger in January 1986.
NASA Astrophysics Data System (ADS)
Helmers, Michael; Herrmann, Michael
2018-03-01
We consider a lattice regularization for an ill-posed diffusion equation with a trilinear constitutive law and study the dynamics of phase interfaces in the parabolic scaling limit. Our main result guarantees for a certain class of single-interface initial data that the lattice solutions satisfy asymptotically a free boundary problem with a hysteretic Stefan condition. The key challenge in the proof is to control the microscopic fluctuations that are inevitably produced by the backward diffusion when a particle passes the spinodal region.
Microbial Groundwater Sampling Protocol for Fecal-Rich Environments
Harter, Thomas; Watanabe, Naoko; Li, Xunde; Atwill, Edward R; Samuels, William
2014-01-01
Inherently, confined animal farming operations (CAFOs) and other intense fecal-rich environments are potential sources of groundwater contamination by enteric pathogens. The ubiquity of microbial matter poses unique technical challenges in addition to economic constraints when sampling wells in such environments. In this paper, we evaluate a groundwater sampling protocol that relies on extended purging with a portable submersible stainless steel pump and Teflon® tubing as an alternative to equipment sterilization. The protocol allows for collecting a large number of samples quickly, relatively inexpensively, and under field conditions with limited access to capacity for sterilizing equipment. The protocol is tested on CAFO monitoring wells and considers three cross-contamination sources: equipment, wellbore, and ambient air. For the assessment, we use Enterococcus, a ubiquitous fecal indicator bacterium (FIB), in laboratory and field tests with spiked and blank samples, and in an extensive, multi-year field sampling campaign on 17 wells within 2 CAFOs. The assessment shows that extended purging can successfully control for equipment cross-contamination, but also controls for significant contamination of the well-head, within the well casing and within the immediate aquifer vicinity of the well-screen. Importantly, our tests further indicate that Enterococcus is frequently entrained in water samples when exposed to ambient air at a CAFO during sample collection. Wellbore and air contamination pose separate challenges in the design of groundwater monitoring strategies on CAFOs that are not addressed by equipment sterilization, but require adequate QA/QC procedures and can be addressed by the proposed sampling strategy. PMID:24903186
NASA Astrophysics Data System (ADS)
Salmaso, Veronica; Sturlese, Mattia; Cuzzolin, Alberto; Moro, Stefano
2018-01-01
Molecular docking is a powerful tool in the field of computer-aided molecular design. In particular, it is the technique of choice for the prediction of a ligand pose within its target binding site. A multitude of docking methods is available nowadays, whose performance may vary depending on the data set. Therefore, some non-trivial choices should be made before starting a docking simulation. In the same framework, the selection of the target structure to use could be challenging, since the number of available experimental structures is increasing. Both issues have been explored within this work. The pose prediction of a pool of 36 compounds provided by D3R Grand Challenge 2 organizers was preceded by a pipeline to choose the best protein/docking-method couple for each blind ligand. An integrated benchmark approach including ligand shape comparison and cross-docking evaluations was implemented inside our DockBench software. The results are encouraging and show that bringing attention to the choice of the docking simulation fundamental components improves the results of the binding mode predictions.
Asero, Riccardo; Fernandez-Rivas, Montserrat; Knulst, André C; Bruijnzeel-Koomen, Carla Afm
2009-08-01
The double-blind, placebo-controlled food challenge (DBPCFC) is widely considered as the 'gold standard' for the diagnosis of food allergy. However, in adult patients, this procedure is rather rarely performed outside the academic context. This review article aims to reappraise the pros and cons of DBPCFC and to elicit some critical thoughts and discussions about the real indications of this diagnostic procedure in adult patients in everyday practice. There are many data showing that the DBPCFC poses a number of critical problems that are difficult to overcome in normal outpatient clinics and hospitals, and that are generally not addressed in most articles dealing with this issue. Performing DBPCFC poses a number of practical problems and has several pitfalls, which make its routine use in normal clinical settings generally impossible. This review article shows that the need for this procedure in adult patients seems in effect very little and specifies new, more limited indications to its use in everyday practice. Further, it suggests a role for the open challenge, which lacks several of the disadvantages of DBPCFC.
Pant, Leela; Kalita, Dipti; Chopra, Ratna; Das, Abhijit; Jain, Gaurav
2015-05-01
Histological diagnosis of adrenal tumors is often challenging as diverse groups of tumors, both primaries and metastatic, may be seen in the adrenal gland with overlapping morphological features. Immunohistochemistry (IHC) plays the most important role in their diagnosis. Perivascular epithelioid cell tumor (PEComa), a rarely reported tumor in the adrenal gland, shares many features with another rare tumor sarcomatoid adrenocortical carcinoma (ACC). Extensive immunohistochemical study is required to distinguish this tumor from adrenocortical carcinoma and from other morphologically similar tumors. The unique combination of immunoreactivity for melanocytic markers, such as HMB-45 and Melan A, and myogenic markers, such as smooth muscle actin, is the hallmark of PEComas biological behavior, and prognosis of malignant PEComas is yet to be fully understood. Few cases of malignant PEComa have been reported in the adrenal gland. We report a case of malignant PEComa of the adrenal gland posing diagnostic challenge and compare its morphological and immunohistochemical features with those of sarcomatoid ACC.
Chatterji, Madhabi
2016-12-01
This paper explores avenues for navigating evaluation design challenges posed by complex social programs (CSPs) and their environments when conducting studies that call for generalizable, causal inferences on the intervention's effectiveness. A definition is provided of a CSP drawing on examples from different fields, and an evaluation case is analyzed in depth to derive seven (7) major sources of complexity that typify CSPs, threatening assumptions of textbook-recommended experimental designs for performing impact evaluations. Theoretically-supported, alternative methodological strategies are discussed to navigate assumptions and counter the design challenges posed by the complex configurations and ecology of CSPs. Specific recommendations include: sequential refinement of the evaluation design through systems thinking, systems-informed logic modeling; and use of extended term, mixed methods (ETMM) approaches with exploratory and confirmatory phases of the evaluation. In the proposed approach, logic models are refined through direct induction and interactions with stakeholders. To better guide assumption evaluation, question-framing, and selection of appropriate methodological strategies, a multiphase evaluation design is recommended. Copyright © 2016 Elsevier Ltd. All rights reserved.
SAMPL4 & DOCK3.7: lessons for automated docking procedures
NASA Astrophysics Data System (ADS)
Coleman, Ryan G.; Sterling, Teague; Weiss, Dahlia R.
2014-03-01
The SAMPL4 challenges were used to test current automated methods for solvation energy, virtual screening, pose and affinity prediction of the molecular docking pipeline DOCK 3.7. Additionally, first-order models of binding affinity were proposed as milestones for any method predicting binding affinity. Several important discoveries about the molecular docking software were made during the challenge: (1) Solvation energies of ligands were five-fold worse than any other method used in SAMPL4, including methods that were similarly fast, (2) HIV Integrase is a challenging target, but automated docking on the correct allosteric site performed well in terms of virtual screening and pose prediction (compared to other methods) but affinity prediction, as expected, was very poor, (3) Molecular docking grid sizes can be very important, serious errors were discovered with default settings that have been adjusted for all future work. Overall, lessons from SAMPL4 suggest many changes to molecular docking tools, not just DOCK 3.7, that could improve the state of the art. Future difficulties and projects will be discussed.
Mass-gathering Events: The Public Health Challenge of the Kumbh Mela 2013.
Dwivedi, Suresh; Cariappa, Mudera P
2015-12-01
Mass-gathering (MG) events pose challenges to the most adept of public health practitioners in ensuring the health safety of the population. These MGs can be for sporting events, musical festivals, or more commonly, have religious undertones. The Kumbh Mela 2013 at Allahabad, India may have been the largest gathering of humanity in history with nearly 120 million pilgrims having thronged the venue. The scale of the event posed a challenge to the maintenance of public health security and safety. A snapshot of the experience of managing the hygiene and sanitation aspects of this mega event is presented herein, highlighting the importance of proactive public health planning and preparedness. There having been no outbreaks of disease is vindication of the steps undertaken in planning and preparedness, notwithstanding obvious limitations of unsanitary behaviors and traditional beliefs of those attending the festival. The evident flaw on post-event analyses was the failure to cater adequately for environmental mopping-up operations after the festival. Besides, a system of real-time monitoring of disease and morbidity patterns, harnessing low cost technology alternatives, should be planned for at all such future events.
Becker, Steven M
2005-11-01
One of the most innovative aspects of NCRP Report No. 138 (Management of Terrorist Incidents Involving Radioactive Material) was the high priority it accorded to psychosocial and communication issues. While previous discussions of radiological and nuclear terrorism had occasionally referred to these topics, NCRP Report No. 138 was the first report of its kind to recognize the profound challenges posed by these issues and to place them at the heart of preparedness and response efforts. In the years since the report's release, a host of important developments have taken place in relation to psychosocial and communication issues. This paper reviews key changes and advances in five broad areas: (1) training exercises, (2) policy and guidance development, (3) findings on hospital and clinician needs, (4) survey research on public perceptions of radiological terrorism, and (5) risk communication for radiological and nuclear terrorism situations. The article concludes with a discussion of continuing psychosocial and communication challenges, including critical areas needing further attention as the nation moves to meet the threat of terrorism involving radioactive materials.
Pose tracking for augmented reality applications in outdoor archaeological sites
NASA Astrophysics Data System (ADS)
Younes, Georges; Asmar, Daniel; Elhajj, Imad; Al-Harithy, Howayda
2017-01-01
In recent years, agencies around the world have invested huge amounts of effort toward digitizing many aspects of the world's cultural heritage. Of particular importance is the digitization of outdoor archaeological sites. In the spirit of valorization of this digital information, many groups have developed virtual or augmented reality (AR) computer applications themed around a particular archaeological object. The problem of pose tracking in outdoor AR applications is addressed. Different positional systems are analyzed, resulting in the selection of a monocular camera-based user tracker. The limitations that challenge this technique from map generation, scale, anchoring, to lighting conditions are analyzed and systematically addressed. Finally, as a case study, our pose tracking system is implemented within an AR experience in the Byblos Roman theater in Lebanon.
Adaptation of an articulated fetal skeleton model to three-dimensional fetal image data
NASA Astrophysics Data System (ADS)
Klinder, Tobias; Wendland, Hannes; Wachter-Stehle, Irina; Roundhill, David; Lorenz, Cristian
2015-03-01
The automatic interpretation of three-dimensional fetal images poses specific challenges compared to other three-dimensional diagnostic data, especially since the orientation of the fetus in the uterus and the position of the extremities is highly variable. In this paper, we present a comprehensive articulated model of the fetal skeleton and the adaptation of the articulation for pose estimation in three-dimensional fetal images. The model is composed out of rigid bodies where the articulations are represented as rigid body transformations. Given a set of target landmarks, the model constellation can be estimated by optimization of the pose parameters. Experiments are carried out on 3D fetal MRI data yielding an average error per case of 12.03+/-3.36 mm between target and estimated landmark positions.
Miller, Dane
2006-01-01
Rob Burns talks with Dane Miller, former CEO of Biomet, about challenges posed by new technology in the orthopedic devices area. One key challenge is the rising cost and use of orthopedic devices at a time when providers are facing decreased profitability and reimbursement for orthopedic services. Another challenge is the long-term time horizon needed to gauge product success that contrasts with payers' and providers' short-term horizon. A third challenge is heightened governmental scrutiny of device makers' relationships with orthopedic surgeons. This interview was conducted before Miller left Biomet in March 2006.
Invasive Plant Management in the United States National Wildlife Refuge
Lusk, Michael; Ericson, Jenny
2011-01-01
Invasive species pose a significant challenge to the National Wildlife Refuge System and have been identified as the single most important threat to habitat management on refuges. At present, it is estimated that over 2 million acres of refuge lands are invaded by invasive plants. The current and potential costs of controlling invasive plants, as well as monitoring and restoring refuge lands, are significant both financially and ecologically. Budgetary expenditures for invasive species projects in FY 2009 totaled $18.4 million. A number of strategies are used to confront this threat and have resulted in success on a variety of levels. The Refuge System utilizes key partnerships, invasive species strike teams, and a dedicated cadre of volunteers to implement projects that incorporate mechanical, chemical and biological control methods.