Exploring the stability of ligand binding modes to proteins by molecular dynamics simulations.

PubMed

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.

Risk management consideration in the bioeconomy

Treesearch

Camilla Abbati de Assis; Ronalds Gonzalez; Stephen Kelley; Hasan Jameel; Ted Bilek; Jesse Daystar; Robert Handfield; Jay Golden; Jeff Prestemon; Damien Singh

2017-01-01

In investing in a new venture, companies aim to increase their competitiveness and generate value in scenarios where volatile markets, geopolitical instabilities, and disruptive technologies create uncertainty and risk. The biobased industry poses additional challenges as it competes in a mature, highly efficient market, dominated by...

Perception of Paralinguistic Intonational Meaning in a Second Language

ERIC Educational Resources Information Center

Chen, Aoju

2009-01-01

Recent studies of paralinguistic intonational meaning show that languages differ systematically in how pitch range is used to signal meaning differences, contra previous claims. This poses an additional challenge to second language learners, who generally receive little tutoring on intonation. This study investigates learners' competence and…

Response to "History of Place, Life Course and Health Inequalities"

EPA Science Inventory

I would like to thank Jamie Pearce for his warm commentary on our paper . Pearce points out the challenges posed by cross-sectional data on the geography of health-related resources. An additional consideration is the potential benefit to considering popu...

Finding Respondents from Minority Groups

ERIC Educational Resources Information Center

Mier, Nelda; Medina, Alvaro A.; Bocanegra-Alonso, Anabel; Castillo-Ruiz, Octelina; Acosta-Gonzalez, Rosa I.; Ramirez, Jose A.

2006-01-01

The recruitment of respondents belonging to ethnic minorities poses important challenges in social and health research. This paper reflects on the enablers and barriers to recruitment that we encountered in our research work with persons belonging to ethnic minorities. Additionally, we applied the Matching Model of Recruitment, a theoretical…

Non-wadeable river bioassessment: spatial variation of benthic diatom assemblages in Pacific Northwest rivers, USA

EPA Science Inventory

Current bioassessment efforts are focused on small wadeable streams, at least partly because assessing ecological conditions in non-wadeable large rivers poses many additional challenges. In this study, we sampled 20 sites in each of seven large rivers in the Pacific Northwest, U...

Factors Influencing the Research Participation of Adults with Autism Spectrum Disorders

ERIC Educational Resources Information Center

Haas, Kaaren; Costley, Debra; Falkmer, Marita; Richdale, Amanda; Sofronoff, Kate; Falkmer, Torbjörn

2016-01-01

Recruiting adults with autism spectrum disorders (ASD) into research poses particular difficulties; longitudinal studies face additional challenges. This paper reports on a mixed methods study to identify factors influencing the participation in longitudinal autism research of adults with ASD, including those with an intellectual disability, and…

The Challenge of Catholicity.

ERIC Educational Resources Information Center

Gallin, Alice, Ed.

1988-01-01

The character and mission of Catholic institutions of higher education are discussed in nine articles. Questions that are posed include: what issues of the Catholic tradition need to be further examined; what additional reading of the Vatican II texts are appropriate; how is one to understand the American context within which the Catolic mission…

Using physics-based pose predictions and free energy perturbation calculations to predict binding poses and relative binding affinities for FXR ligands in the D3R Grand Challenge 2

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.

Small is challenging; distal femur fracture management in an elderly lady with achondroplastic dwarfism.

PubMed

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.

Using Feature Films to Teach Public Relations: An Assessment Model from Nonmajor Students' Perspective

ERIC Educational Resources Information Center

Mak, Angela Ka Ying; Hutton, James G.

2014-01-01

Teaching fundamental public relations courses to students from diverse backgrounds poses additional complexities in learning effectiveness. This exploratory study evaluated the effectiveness and identified the challenges of using films to teach public relations among nonmajor students. Results from an online survey and two focus groups found that…

Debates in the Literature on Islamic Schools

ERIC Educational Resources Information Center

Elbih, Randa

2012-01-01

Contemporary global events, such as the wars in Iraq and Afghanistan, the unresolved conflict in the Middle East, and the pessimistic relationships with Muslim countries, pose challenges for Muslims living in the United States in all walks of life. In addition, Muslims encounter daily struggles to live within a society that follows considerably…

Impact of Additional Guidance in Science Education on Primary Students' Conceptual Understanding

ERIC Educational Resources Information Center

Decristan, Jasmin; Hondrich, A. Lena; Büttner, Gerhard; Hertel, Silke; Klieme, Eckhard; Kunter, Mareike; Lühken, Arnim; Adl-Amini, Katja; Djakovic, Sanna-K.; Mannel, Susanne; Naumann, Alexander; Hardy, Ilonca

2015-01-01

A cognitive and a guidance dimension can describe the support of students' conceptual understanding in inquiry-based science education. The role of guidance for student learning has been intensively discussed. Furthermore, inquiry learning may pose particular challenges to students with low language proficiency. The present intervention in primary…

Curriculum Change Management and Workload

ERIC Educational Resources Information Center

Alkahtani, Aishah

2017-01-01

This study examines the ways in which Saudi teachers have responded or are responding to the challenges posed by a new curriculum. It also deals with issues relating to workload demands which affect teachers' performance when they apply a new curriculum in a Saudi Arabian secondary school. In addition, problems such as scheduling and sharing space…

Precision Manipulation with Cooperative Robots

NASA Technical Reports Server (NTRS)

Stroupe, Ashley; Huntsberger, Terry; Okon, Avi; Aghzarian, Hrand

2005-01-01

This work addresses several challenges of cooperative transportThis work addresses several challenges of cooperative transport and precision manipulation. Precision manipulation requires a rigid grasp, which places a hard constraint on the relative rover formation that must be accommodated, even though the rovers cannot directly observe their relative poses. Additionally, rovers must jointly select appropriate actions based on all available sensor information. Lastly, rovers cannot act on independent sensor information, but must fuse information to move jointly; the methods for fusing information must be determined.

International and cross-cultural issues: six key challenges for our professions.

PubMed

Marshall, Julie

2003-01-01

This paper discusses a number of key challenges facing professionals who work with people who have communication disabilities. The challenges are related to working internationally and in a cross-culturally competent way. Each challenge is discussed, drawing on material from a range of sources, including the papers in the final 2003 edition of FOLIA PHONIATRICA ET LOGOPAEDICA ('International and Cross-Cultural Issues'). The challenges discussed cover how experiences from majority world countries can be used to benefit services elsewhere, 'mainstreaming' commitment to cross-cultural competence, learning from relationships with other professionals, influencing research practice, responding to requests to work internationally and finally, dealing with cultural differences that challenge working practices. Some solutions are suggested and additional questions posed. Copyright 2003 S. Karger AG, Basel

Perioperative lung protective ventilation in obese patients.

PubMed

Fernandez-Bustamante, Ana; Hashimoto, Soshi; Serpa Neto, Ary; Moine, Pierre; Vidal Melo, Marcos F; Repine, John E

2015-05-06

The perioperative use and relevance of protective ventilation in surgical patients is being increasingly recognized. Obesity poses particular challenges to adequate mechanical ventilation in addition to surgical constraints, primarily by restricted lung mechanics due to excessive adiposity, frequent respiratory comorbidities (i.e. sleep apnea, asthma), and concerns of postoperative respiratory depression and other pulmonary complications. The number of surgical patients with obesity is increasing, and facing these challenges is common in the operating rooms and critical care units worldwide. In this review we summarize the existing literature which supports the following recommendations for the perioperative ventilation in obese patients: (1) the use of protective ventilation with low tidal volumes (approximately 8 mL/kg, calculated based on predicted -not actual- body weight) to avoid volutrauma; (2) a focus on lung recruitment by utilizing PEEP (8-15 cmH2O) in addition to recruitment maneuvers during the intraoperative period, as well as incentivized deep breathing and noninvasive ventilation early in the postoperative period, to avoid atelectasis, hypoxemia and atelectrauma; and (3) a judicious oxygen use (ideally less than 0.8) to avoid hypoxemia but also possible reabsorption atelectasis. Obesity poses an additional challenge for achieving adequate protective ventilation during one-lung ventilation, but different lung isolation techniques have been adequately performed in obese patients by experienced providers. Postoperative efforts should be directed to avoid hypoventilation, atelectasis and hypoxemia. Further studies are needed to better define optimum protective ventilation strategies and analyze their impact on the perioperative outcomes of surgical patients with obesity.

Electronic cigarette explosions involving the oral cavity.

PubMed

Harrison, Rebecca; Hicklin, David

2016-11-01

The use of electronic cigarettes (e-cigarettes) is a rapidly growing trend throughout the United States. E-cigarettes have been linked to the risk of causing explosion and fire. Data are limited on the associated health hazards of e-cigarette use, particularly long-term effects, and available information often presents conflicting conclusions. In addition, an e-cigarette explosion and fire can pose a unique treatment challenge to the dental care provider because the oral cavity may be affected heavily. In this particular case, the patient's injuries included intraoral burns, luxation injuries, and alveolar fractures. This case report aims to help clinicians gain an increased knowledge about e-cigarette design, use, and risks; discuss the risk of spontaneous failure and explosion of e-cigarettes with patients; and understand the treatment challenges posed by an e-cigarette explosion. Copyright © 2016 American Dental Association. Published by Elsevier Inc. All rights reserved.

Grade 4 Learners' Linguistic Difficulties in Solving Mathematical Assessments

ERIC Educational Resources Information Center

Sibanda, Lucy

2017-01-01

The underperformance of South African learners in literacy and numeracy is a cause of concern, especially at the transition from Grade 3 to Grade 4. At Grade 4 in South Africa, the majority of learners begin learning in English, which to them is an additional language posing transition challenges of a linguistic nature. The sustained poor…

How Do Schools Compensate for Socio-Economic Disadvantage? PISA in Focus No. 76

ERIC Educational Resources Information Center

OECD Publishing, 2017

2017-01-01

As educators know well, there are many barriers to learning that originate outside of school, such as those that arise from socio-economic disadvantage. In many education systems, the concentration of disadvantaged students in certain schools poses an additional challenge. Yet it is also true that schools with effective learning environments and…

Ethnic and Racial Socialization and Self-Esteem of Asian Adoptees: The Mediating Role of Multiple Identities

ERIC Educational Resources Information Center

Mohanty, Jayashree

2013-01-01

Positive identity development during adolescence in general is a complex process and may pose additional challenges for adolescents adopted from a different culture. Using a web-based survey design with a sample of 100 internationally adopted Asian adolescent and young adults, the present study examined the mediating role of multiple identities…

Serving the Information Needs of the International and Minority Students at the Small College Library: A Librarian's View.

ERIC Educational Resources Information Center

Burhans, Skip

International and minority students often pose additional challenges due to cultural, linguistic, or socio-economic differences with the mostly white, middle class, highly educated (and predominantly female) public service librarians with whom they come into contact. Such differences can range from minor speech/articulation problems to major…

Body Parts Dependent Joint Regressors for Human Pose Estimation in Still Images.

PubMed

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.

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.

Implications and challenges for implementation of the FDA’s final deeming rule for waterpipe tobacco

PubMed Central

Sutfin, Erin L; Soule, Eric K; McKelvey, Karma; Jenson, Desmond

2017-01-01

For the first time, the Food and Drug Administration’s (FDAs) Center for Tobacco Products now has regulatory authority over all tobacco products, including waterpipe tobacco. In the rule expanding its authority to cover all tobacco products, the FDA uses largely a one-size-fits-all approach. However, several aspects of waterpipe tobacco smoking make it unique from other tobacco products, which may require more specific, tailored rules. This paper describes the distinct features of waterpipe tobacco products and accessories, and identifies unique challenges to the current regulation posed by this form of tobacco use. Additionally, we highlight the need for further research-generated evidence to support additional rulemaking. PMID:28667092

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.

“You’re dealing with an emotionally charged individual…”: an industry perspective on the challenges posed by medical tourists’ informal caregiver-companions

PubMed Central

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

"You're dealing with an emotionally charged individual...": an industry perspective on the challenges posed by medical tourists' informal caregiver-companions.

PubMed

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.

Neoliberalism and Illusion: The Importance of Preparing Students to Live in the 21st Century

ERIC Educational Resources Information Center

Fitzner, Jennifer

2017-01-01

While this paper discusses the history of neoliberalism with emphasis on the role of the United States, it also addresses the challenges neoliberalism poses for individuals. Additionally, the paper discusses the failure of school curriculum to prepare youth in the United States for growing economic uncertainty, as well as media's role in hindering…

Using Simplified English to Identify Potential Problems for Non-Native Speakers in the Language of Engineering Examination Papers

ERIC Educational Resources Information Center

Harrison, Sandra; Morgan, Roger

2012-01-01

There is an increasing sensitivity to the challenges posed by the language of examination papers and of instruction in scientific subjects, especially for non-native speakers of English. It has been observed that in addition to technical subject-specific vocabulary, non-technical words such as instructional verbs have been sources of difficulty,…

Guidance and Control of a Man-Portable Precision Munition Concept

DTIC Science & Technology

2014-06-01

challenges posed by characteristics of spin-stabilized flight dynamics such as limit cycles, center -of- gravity swerve, instability, and practical...Control Line-of-sight rate and closing velocity estimates are used to form proportional navigation commands in classical guidance schemes...Accelerometers and gyroscopes often supply additional necessary feedback. The accelerometers ensure that the airframe is maneuvering the center of gravity

Primary and Secondary Teachers' Ideas on School Visits to Science Centres in the Basque Country

ERIC Educational Resources Information Center

Morentin, Maite; Guisasola, Jenaro

2015-01-01

In recent decades, research has shown the challenge posed to teachers by science education in informal contexts such as science museums or centres. In addition, there is consensus that in the case of pupils visiting a science centre, learning improves when the visit is connected to the classroom curriculum, so the teachers' involvement in…

Mother and Child: Medication Use in Pregnancy and Lactation.

PubMed

Ito, S

2016-07-01

Pregnancy and breastfeeding pose a unique challenge to drug development and clinical application. In addition to drug toxicity to the fetus in utero and infants through breastfeeding, alterations of pharmacokinetics in those women also need careful attention. How do we turn around the overall lack of drug efficacy and toxicity information for pregnant and breastfeeding women? © 2016 ASCPT.

Lessons learned in induced fit docking and metadynamics in the Drug Design Data Resource Grand Challenge 2

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.

Integrated Speech and Language Technology for Intelligence, Surveillance, and Reconnaissance (ISR)

DTIC Science & Technology

2017-07-01

applying submodularity techniques to address computing challenges posed by large datasets in speech and language processing. MT and speech tools were...aforementioned research-oriented activities, the IT system administration team provided necessary support to laboratory computing and network operations...operations of SCREAM Lab computer systems and networks. Other miscellaneous activities in relation to Task Order 29 are presented in an additional fourth

A Glossary of Research Terms for Out-of-School Time Program Practitioners. Research-to-Results Fact Sheet. Publication #2007-02

ERIC Educational Resources Information Center

Bronte-Tinkew, Jacinta; Horowitz, Allison; Redd, Zakia; Moore, Kristin A.; Valladares, Sherylls

2007-01-01

This glossary of common research and evaluation terms can serve as a quick reference guide for out-of school time practitioners as they face the challenges posed in this new era of program accountability. Subsequent briefs will provide more detailed information on particular types of research and evaluation designs. A list of additional resources…

Security Planning and Policies to Meet the Challenges of Climate Change

DTIC Science & Technology

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.

Distributed Prognostic Health Management with Gaussian Process Regression

NASA Technical Reports Server (NTRS)

Saha, Sankalita; Saha, Bhaskar; Saxena, Abhinav; Goebel, Kai Frank

2010-01-01

Distributed prognostics architecture design is an enabling step for efficient implementation of health management systems. A major challenge encountered in such design is formulation of optimal distributed prognostics algorithms. In this paper. we present a distributed GPR based prognostics algorithm whose target platform is a wireless sensor network. In addition to challenges encountered in a distributed implementation, a wireless network poses constraints on communication patterns, thereby making the problem more challenging. The prognostics application that was used to demonstrate our new algorithms is battery prognostics. In order to present trade-offs within different prognostic approaches, we present comparison with the distributed implementation of a particle filter based prognostics for the same battery data.

Sustainable Materials Management (SMM) Web Academy Webinar: An Introduction to Lithium Batteries and the Challenges that they Pose to the Waste and Recycling Industry

EPA Pesticide Factsheets

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.

Threats to US energy security: the challenge of Arab oil

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

Phillips, J.

1979-08-13

Assured access to foreign oil supplies is a vital national interest of the United States which has been repeatedly jeopardized in the 1970s and one that will face additional critical challenges in the 1980s. This paper identifies and analyzes various threats to US energy security both in terms of their past use and future usability. Since the most ominous threat to US energy security is posed in connection with the Arab-Israeli conflict, the paper focuses on the Arab oil weapon, although the energy-security implications of the Iranian revolution are also assessed.

Imaging of thymic disorders

PubMed Central

Bogot, Naama R; Quint, Leslie E

2005-01-01

Evaluation of the thymus poses a challenge to the radiologist. In addition to age-related changes in thymic size, shape, and tissue composition, there is considerable variability in the normal adult thymic appearance within any age group. Many different types of disorders may affect the thymus, including hyperplasia, cysts, and benign and malignant neoplasms, both primary and secondary; clinical and imaging findings typical for each disease process are described in this article. Whereas computed tomography is the mainstay for imaging the thymus, other imaging modalities may occasionally provide additional structural or functional information. PMID:16361143

Invisible Wounds of War. Psychological and Cognitive Injuries, Their Consequences, and Services to Assist Recovery

DTIC Science & Technology

2008-01-01

Education. Comper et al. (2005) reviewed seven studies in which patients were given an information intervention. The interventions included reassurance...information on the recovery process, or strategies for managing mild-TBI symptoms. Comper and associates found sufficient evidence to conclude that...numbers and heterogeneity of brain-injured patients pose additional challenges (Turner-Stokes and Wade, 2004). Pharmacotherapy. Comper and colleagues (2005

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…

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…

Ranking docking poses by graph matching of protein-ligand interactions: lessons learned from the D3R Grand Challenge 2

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.

Military Operations Research. Winter 1996. Volume 1, Number 4

DTIC Science & Technology

1996-01-01

ANALYSIS DISTURBANCE INPUT OUTPUT PLANT SEMANTIC CONTROL SYSTEM CONTROL DESIGNER CONTROL I i LAW SYSTEM GOAL CONTROL IIDENTIFIER SELECTOR ADAPTER CONTRO...analysts for many years. It is designed to provide a quick reference for models that represent the effects of a conventional attack against ground...satellites offer this capability. This poses the additional challenge as to how many highways one can "see" per unit time. He did, however, design a

Multi-channel probes to understand fission dynamics

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

Mosby, Shea Morgan

2016-04-15

Explaining the origin of the elements is a major outstanding question in nuclear astrophysics. Observed elemental abundance distribution shows strong nuclear physics effects. In conclusion, neutron-induced reactions are important for nuclear astrophysics and applied fields in nuclear energy and security. LANSCE has a program to address many of these questions directly with neutron beams on (near-)stable nuclei. Increasing demand for correlated data to test details of fission models poses additional challenges. Possibilities exist to extend existing experimental efforts to radioactive beam facilities. Kinematic focusing from using inverse kinematics has potential to circumvent some challenges associated with measuring correlations between fissionmore » output channels.« less

Optimizing care for the obese patient in interventional radiology

PubMed Central

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

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.

Analysis of Problems Posed by Sixth-Grade Middle School Students for the Addition of Fractions in Terms of Semantic Structures

ERIC Educational Resources Information Center

Kar, Tugrul

2015-01-01

This study aimed to investigate how the semantic structures of problems posed by sixth-grade middle school students for the addition of fractions affect their problem-posing performance. The students were presented with symbolic operations involving the addition of fractions and asked to pose two different problems related to daily-life situations…

A taxonomic framework for assessing governance challenges and environmental effects of integrated food-energy systems.

PubMed

Gerst, Michael D; Cox, Michael E; Locke, Kim A; Laser, Mark; Kapuscinski, Anne R

2015-01-20

Predominant forms of food and energy systems pose multiple challenges to the environment as current configurations tend to be structured around centralized one-way through-put of materials and energy. In addition, these configurations can introduce vulnerability to input material price and supply shocks as well as contribute to localized food insecurity and lost opportunities for less environmentally harmful forms of local economic development. One proposed form of system transformation involves locally integrating “unclosed” material and energy loops from food and energy systems. Such systems, which have been termed integrated food-energy systems (IFES), have existed in diverse niche forms but have not been systematically studied with respect to technological, governance, and environmental differences. As a first step in this process, we have constructed a taxonomy of IFES archetypes by using exploratory data analysis on a collection of IFES cases. We find that IFES may be classified hierarchically first by their primary purpose—food or energy production—and subsequently by degree and direction of vertical supply chain coordination. We then use this taxonomy to delineate potential governance challenges and pose a research agenda aimed at understanding what role IFES may play in food and energy system transformation and ultimately what policies may encourage IFES adoption.

Meeting the policy agenda, part 1: the role of the modern district nurse.

PubMed

Dickson, Caroline A W; Gough, Helen; Bain, Heather

2011-10-01

The challenges posed by the current context of health and social care offer opportunities for different models of care delivery. District nursing has evolved, and continues to evolve to meet these challenges. The traditional reactive role of district nursing has developed as contemporary practice expects district nurses to meet both planned and unplanned care required by practice populations. Modern anticipatory care approaches to care are being adopted, while care and case management is being facilitated and delivered to patients and families with complex health and social care needs. Additionally, district nurses are recognizing the need to further develop management and leadership skills as the teams delivering care consist of a skill mix of nurses and other disciplines. They are also charged with evidencing the impact of what they do and influencing care delivery at every level of healthcare organizations. This first paper of two will explore the current UK policy context and ways in which district nursing services within each country are changing to meet the challenges posed. A second article will argue the need to ensure the district nursing workforce is underpinned by robust educational standards that ensure protection of the public. The influences of education and development from professional and organizational perspectives will be examined.

The Promise of Cell Based Therapies for Diabetic Complications: challenges and solutions

PubMed Central

Jarajapu, Yagna P.R.; Grant, Maria B.

2013-01-01

The discovery of endothelial progenitor cells (EPCs) in human peripheral blood advanced the field of cell-based therapeutics for many pathological conditions. Despite the lack of agreement about the existence and characteristics of EPCs, autologous EPC populations represent a novel treatment option for complications requiring therapeutic revascularization and vascular repair. Patients with diabetic complications represent a population of patients that may benefit from cellular therapy yet their broadly dysfunctional cells may limit the feasibility of this approach. Diabetic EPCs have decreased migratory prowess and reduced proliferative capacity and an altered cytokine/ growth factor secretory profile that can accelerates deleterious repair mechanisms rather than support proper vascular repair. Furthermore, the diabetic environment poses additional challenges for the autologous transplantation of cells. The present review is focused on correcting diabetic EPC dysfunction and the challenges involved in the application of cell-based therapies for treatment of diabetic vascular complications. In addition, ex vivo and in vivo functional manipulation(s) of EPCs to overcome these hurdles are discussed. PMID:20299675

Vision Based SLAM in Dynamic Scenes

DTIC Science & Technology

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

Trusted Remote Operation of Proximate Emergy Robots (TROOPER): DARPA Robotics Challenge

DTIC Science & Technology

2015-12-01

sensor in each of the robot’s feet. Additionally, there is a 6-axis IMU that sits in the robot’s pelvis cage. While testing before the Finals, the...Services. Many of the controllers in the autonomic layer have overlapping requirements, such as filtered IMU and force torque data from the robot...the following services during the DRC: • IMU Filtering • Force Torque Filtering • Joint State Publishing • TF (Transform) Broadcasting • Robot Pose

Trusted Remote Operation of Proximate Emergency Robots (TROOPER): DARPA Robotics Challenge

DTIC Science & Technology

2015-12-01

sensor in each of the robot’s feet. Additionally, there is a 6-axis IMU that sits in the robot’s pelvis cage. While testing before the Finals, the...Services. Many of the controllers in the autonomic layer have overlapping requirements, such as filtered IMU and force torque data from the robot...the following services during the DRC: • IMU Filtering • Force Torque Filtering • Joint State Publishing • TF (Transform) Broadcasting • Robot Pose

Implementing a High-Assurance Smart-Card OS

NASA Astrophysics Data System (ADS)

Karger, Paul A.; Toll, David C.; Palmer, Elaine R.; McIntosh, Suzanne K.; Weber, Samuel; Edwards, Jonathan W.

Building a high-assurance, secure operating system for memory constrained systems, such as smart cards, introduces many challenges. The increasing power of smart cards has made their use feasible in applications such as electronic passports, military and public sector identification cards, and cell-phone based financial and entertainment applications. Such applications require a secure environment, which can only be provided with sufficient hardware and a secure operating system. We argue that smart cards pose additional security challenges when compared to traditional computer platforms. We discuss our design for a secure smart card operating system, named Caernarvon, and show that it addresses these challenges, which include secure application download, protection of cryptographic functions from malicious applications, resolution of covert channels, and assurance of both security and data integrity in the face of arbitrary power losses.

The 2014 Sandia Verification and Validation Challenge: Problem statement

DOE PAGES

Hu, Kenneth; Orient, George

2016-01-18

This paper presents a case study in utilizing information from experiments, models, and verification and validation (V&V) to support a decision. It consists of a simple system with data and models provided, plus a safety requirement to assess. The goal is to pose a problem that is flexible enough to allow challengers to demonstrate a variety of approaches, but constrained enough to focus attention on a theme. This was accomplished by providing a good deal of background information in addition to the data, models, and code, but directing the participants' activities with specific deliverables. In this challenge, the theme ismore » how to gather and present evidence about the quality of model predictions, in order to support a decision. This case study formed the basis of the 2014 Sandia V&V Challenge Workshop and this resulting special edition of the ASME Journal of Verification, Validation, and Uncertainty Quantification.« less

A deep learning approach for pose estimation from volumetric OCT data.

PubMed

Gessert, Nils; Schlüter, Matthias; Schlaefer, Alexander

2018-05-01

Tracking the pose of instruments is a central problem in image-guided surgery. For microscopic scenarios, optical coherence tomography (OCT) is increasingly used as an imaging modality. OCT is suitable for accurate pose estimation due to its micrometer range resolution and volumetric field of view. However, OCT image processing is challenging due to speckle noise and reflection artifacts in addition to the images' 3D nature. We address pose estimation from OCT volume data with a new deep learning-based tracking framework. For this purpose, we design a new 3D convolutional neural network (CNN) architecture to directly predict the 6D pose of a small marker geometry from OCT volumes. We use a hexapod robot to automatically acquire labeled data points which we use to train 3D CNN architectures for multi-output regression. We use this setup to provide an in-depth analysis on deep learning-based pose estimation from volumes. Specifically, we demonstrate that exploiting volume information for pose estimation yields higher accuracy than relying on 2D representations with depth information. Supporting this observation, we provide quantitative and qualitative results that 3D CNNs effectively exploit the depth structure of marker objects. Regarding the deep learning aspect, we present efficient design principles for 3D CNNs, making use of insights from the 2D deep learning community. In particular, we present Inception3D as a new architecture which performs best for our application. We show that our deep learning approach reaches errors at our ground-truth label's resolution. We achieve a mean average error of 14.89 ± 9.3 µm and 0.096 ± 0.072° for position and orientation learning, respectively. Copyright © 2018 Elsevier B.V. All rights reserved.

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.…

Challenges facing an understanding of the nature of low-energy excited states in photosynthesis.

PubMed

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.

Meeting the challenge of interpretation: Hearing the voices of people with intellectual and developmental disability through I-Poems.

PubMed

Corby, Deirdre; Taggart, Laurence; Cousins, Wendy

2018-06-01

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 data collection. An argument is made for the systematic application of the guide with a focus on the use of I-Poems. This article advances qualitative methodological approaches and concludes that this method of drawing attention to the participants' own voices provides a unique basis for interpreting interviews and tasks researchers to examine the use of the Listening Guide.

HIV treatment in US prisons.

PubMed

Wakeman, Sarah E; Rich, Josiah D

2010-09-03

Arguably one of the most marginalized populations in our society, prisoners bear a disproportionate burden of infectious diseases, particularly HIV. In addition, groups known to be at an inordinately higher risk of HIV, including minorities, the addicted, the mentally ill and the impoverished are overrepresented among incarcerated populations. This concentration of HIV among groups that have been historically difficult to reach, with limited intersections with healthcare, provides an opportunity for testing, diagnosis, treatment, linkage to care and prevention. Providing HIV care within correctional facilities poses unique challenges. Barriers to confidentiality, access to medication and prior records, and lack of comprehensive discharge planning can serve as obstacles to providing optimal care. This article discusses the public health implications and importance of providing HIV care to prisoners, and also discusses the practicalities of working within an environment that poses particular barriers to care.

Obesity: The Modifiable Risk Factor in Total Joint Arthroplasty.

PubMed

Bookman, Jared S; Schwarzkopf, Ran; Rathod, Parthiv; Iorio, Richard; Deshmukh, Ajit J

2018-07-01

Obesity is an epidemic in the health care system. Obesity poses several challenges and raises unique issues for the arthroplasty surgeon. Obese patients are at higher risk for infection and dislocation. Additionally, obese patients have poorer implant survivorship and functional scores postoperatively. Obesity is a modifiable risk factor and weight loss preoperatively should be strongly considered. Obese patients must be counseled so that they have realistic expectations after total joint arthroplasty. Copyright © 2018 Elsevier Inc. All rights reserved.

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.

DOCKSCORE: a webserver for ranking protein-protein docked poses.

PubMed

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/ .

A machine learning approach for ranking clusters of docked protein‐protein complexes by pairwise cluster comparison

PubMed Central

Pfeiffenberger, Erik; Chaleil, Raphael A.G.; Moal, Iain H.

2017-01-01

ABSTRACT Reliable identification of near‐native poses of docked protein–protein complexes is still an unsolved problem. The intrinsic heterogeneity of protein–protein interactions is challenging for traditional biophysical or knowledge based potentials and the identification of many false positive binding sites is not unusual. Often, ranking protocols are based on initial clustering of docked poses followed by the application of an energy function to rank each cluster according to its lowest energy member. Here, we present an approach of cluster ranking based not only on one molecular descriptor (e.g., an energy function) but also employing a large number of descriptors that are integrated in a machine learning model, whereby, an extremely randomized tree classifier based on 109 molecular descriptors is trained. The protocol is based on first locally enriching clusters with additional poses, the clusters are then characterized using features describing the distribution of molecular descriptors within the cluster, which are combined into a pairwise cluster comparison model to discriminate near‐native from incorrect clusters. The results show that our approach is able to identify clusters containing near‐native protein–protein complexes. In addition, we present an analysis of the descriptors with respect to their power to discriminate near native from incorrect clusters and how data transformations and recursive feature elimination can improve the ranking performance. Proteins 2017; 85:528–543. © 2016 Wiley Periodicals, Inc. PMID:27935158

Correlated Imaging – A Grand Challenge in Chemical Analysis

PubMed Central

Masyuko, Rachel; Lanni, Eric; Sweedler, Jonathan V.; Bohn, Paul W.

2013-01-01

Correlated chemical imaging is an emerging strategy for acquisition of images by combining information from multiplexed measurement platforms to track, visualize, and interpret in situ changes in the structure, organization, and activities of interesting chemical systems, frequently spanning multiple decades in space and time. Acquiring and correlating information from complementary imaging experiments has the potential to expose complex chemical behavior in ways that are simply not available from single methods applied in isolation, thereby greatly amplifying the information gathering power of imaging experiments. However, in order to correlate image information across platforms, a number of issues must be addressed. First, signals are obtained from disparate experiments with fundamentally different figures of merit, including pixel size, spatial resolution, dynamic range, and acquisition rates. In addition, images are often acquired on different instruments in different locations, so the sample must be registered spatially so that the same area of the sample landscape is addressed. The signals acquired must be correlated in both spatial and temporal domains, and the resulting information has to be presented in a way that is readily understood. These requirements pose special challenges for image cross-correlation that go well beyond those posed in single technique imaging approaches. The special opportunities and challenges that attend correlated imaging are explored by specific reference to correlated mass spectrometric and Raman imaging, a topic of substantial and growing interest. PMID:23431559

Docking of small molecules to farnesoid X receptors using AutoDock Vina with the Convex-PL potential: lessons learned from D3R Grand Challenge 2

NASA Astrophysics Data System (ADS)

Kadukova, Maria; Grudinin, Sergei

2018-01-01

The 2016 D3R Grand Challenge 2 provided an opportunity to test multiple protein-ligand docking protocols on a set of ligands bound to farnesoid X receptor that has many available experimental structures. We participated in the Stage 1 of the Challenge devoted to the docking pose predictions, with the mean RMSD value of our submission poses of 2.9 Å. Here we present a thorough analysis of our docking predictions made with AutoDock Vina and the Convex-PL rescoring potential by reproducing our submission protocol and running a series of additional molecular docking experiments. We conclude that a correct receptor structure, or more precisely, the structure of the binding pocket, plays the crucial role in the success of our docking studies. We have also noticed the important role of a local ligand geometry, which seems to be not well discussed in literature. We succeed to improve our results up to the mean RMSD value of 2.15-2.33 Å dependent on the models of the ligands, if docking these to all available homologous receptors. Overall, for docking of ligands of diverse chemical series we suggest to perform docking of each of the ligands to a set of multiple receptors that are homologous to the target.

Linking Space Weather Science and Decision Making (Invited)

NASA Astrophysics Data System (ADS)

Fisher, G. M.

2009-12-01

Linking scientific knowledge to decision making is a challenge for both the science and policy communities. In particular, in the field of space weather, there are unique challenges such as decision makers may not know that space has weather that poses risks to our technologically-dependent economy. Additionally, in an era of limited funds for scientific research, hazards posed by other natural disasters such as flooding and earthquakes are by contrast well known to policy makers, further making the importance of space weather research and monitoring a tough sell. Today, with industries and individuals more dependent on the Global Positioning System, wireless technology, and satellites than ever before, any disruption or inaccuracy can result in severe economic impacts. Therefore, it is highly important to understand how space weather science can most benefit society. The key to connecting research to decision making is to ensure that the information is salient, credible, and legitimate. To achieve this, scientists need to understand the decision makers' perspectives, including their language and culture, and recognize that their needs may evolve. This presentation will take a closer look at the steps required to make space weather research, models, and forecasts useful to decision makers and ultimately, benefit society.

Stochastic characterization of small-scale algorithms for human sensory processing

NASA Astrophysics Data System (ADS)

Neri, Peter

2010-12-01

Human sensory processing can be viewed as a functional H mapping a stimulus vector s into a decisional variable r. We currently have no direct access to r; rather, the human makes a decision based on r in order to drive subsequent behavior. It is this (typically binary) decision that we can measure. For example, there may be two external stimuli s[0] and s[1], mapped onto r[0] and r[1] by the sensory apparatus H; the human chooses the stimulus associated with largest r. This kind of decisional transduction poses a major challenge for an accurate characterization of H. In this article, we explore a specific approach based on a behavioral variant of reverse correlation techniques, where the input s contains a target signal corrupted by a controlled noisy perturbation. The presence of the target signal poses an additional challenge because it distorts the otherwise unbiased nature of the noise source. We consider issues arising from both the decisional transducer and the target signal, their impact on system identification, and ways to handle them effectively for system characterizations that extend to second-order functional approximations with associated small-scale cascade models.

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

ERIC Educational Resources Information Center

Haag, Patricia W.

2015-01-01

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

Irritable bowel syndrome in children: Current knowledge, challenges and opportunities

PubMed Central

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

Improved pose and affinity predictions using different protocols tailored on the basis of data availability

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).

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

Cai, Yunhai

Similar to a super B-factory, a circular Higgs factory (CHF) will require strong focusing systems near the interaction points and a low-emittance lattice in the arcs to achieve a factory luminosity. At electron beam energy of 125 GeV, beamstrahlung effects during the collision pose an additional challenge to the collider design. In particular, a large momentum acceptance at the 2% level is necessary to retain an adequate beam lifetime. This turns out to be the most challenging aspect in the design of a CHF. In this paper, an example will be provided to illustrate the beam dynamics in a CHF,more » emphasizing the chromatic optics. Basic optical modules and advanced analysis will be presented. Most importantly, we will show that 2% momentum aperture is achievable.« less

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

Cai, Yunhai

Similar to a super B-factory, a circular Higgs factory will require strong focusing systems near the interaction points and a low-emittance lattice in arcs to achieve a factory luminosity. At electron beam energy of 120 GeV, beamstrahlung effects during the collision pose an additional challenge to the collider design. In particular, a large momentum acceptance at 2 percent level is necessary to retain an adequate beam lifetime. This turns out to be the most challenging aspect in the design of circular Higgs factory. In this paper, an example will be provided to illustrate the beam dynamics in circular Higgs factory,more » emphasizing on the chromatic optics. Basic optical modules and advanced analysis will be presented. Most important, we will show that 2% momentum aperture is achievable« less

High left ventricular outflow tract gradient: Aortic stenosis, obstructive hypertrophic cardiomyopathy or both?

PubMed

Almeida, Inês; Caetano, Francisca; Trigo, Joana; Mota, Paula; Marques, António Leitão

2015-05-01

The authors report the case of a patient diagnosed with both hypertrophic cardiomyopathy and aortic stenosis. Due to clinical deterioration, additional investigation was performed, and a high left ventricular outflow tract gradient was identified. Correct identification of the condition causing the symptoms was challenging, and involved several imaging techniques, the contribution of transesophageal echocardiography being crucial. The final diagnosis of severe aortic stenosis led to successful valve replacement surgery. The presence of these two conditions in the same patient has been documented, although it is uncommon. This association poses particular diagnostic and therapeutic challenges, which are discussed in this paper. Copyright © 2015 Sociedade Portuguesa de Cardiologia. Published by Elsevier España. All rights reserved.

Social Entrepreneurship for Obesity Prevention: What Are the Opportunities?

PubMed

Smith, Tosha Woods; Calancie, Larissa; Ammerman, Alice

2015-09-01

In recent years, social entrepreneurship has emerged as a new field to address social and public health challenges. Social entrepreneurship, which harnesses traditional business practices and market forces to address social challenges, may produce solutions that are more cost-effective and sustainable than those produced by governmental and nonprofit sectors. In this paper, we discuss whether and how social entrepreneurship can be harnessed for obesity prevention by defining and briefly reviewing the rise of social entrepreneurship in the USA, outlining the threat that obesity poses to US society and offering some examples of how social ventures are addressing the problem of obesity. Additional untapped opportunities are also discussed and recommendations given for how social entrepreneurship might impact obesity prevention in the future.

Cockpit Accommodation Assessment of the Bell 412CF Helicopter (Evaluation du Poste de Pilotage de l’Hellcoptere Bell 412CF)

DTIC Science & Technology

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

Single leg balancing in ballet: effects of shoe conditions and poses.

PubMed

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.

Benefits and concerns associated with biotechnology-derived foods: can additional research reduce children health risks?

PubMed

Cantani, A

2009-01-01

The development of techniques devised for the genetic manipulation of foods poses new risks for children with food allergy (FA). The introduction of foreign allergenic proteins from different foods into previously tolerated foods may trigger allergic reactions, often complicating with anaphylactic shock in a subset of allergic babies. Children with FA, even if subjected to preventative diets, always challenge the risk of developing allergic manifestations after unintentional intake of a non tolerated food in restaurant settings, with relatives or schoolmates, etc, where product labelling is necessarily lacking. The introduction of potentially allergenic proteins into foods generally considered safe for allergic children can be done deliberately, by either substantially altering the food ingredients, or by genetic manipulation which change the composition or transfer allergens, or unintentionally by qualitycontrol failures, due to contaminations in the production process, or to genetic mismanipulation. There is a controversy between multinationals often favored by governments and consumer association resistance, thus an equidistant analysis poses some unprecedented impediments. The importance of FA and the potential of transgenic plants to bring food allergens into the food supply should not be disregarded. The expression in soybeans of a Brazil nut protein resulted in a food allergen ex-pressed in widely used infant formulas, so paving the way to an often reported multinational debacle. Genetic engineering poses innovative ethical and social concerns, as well as serious challenges to the environment, human health, animal welfare, and the future of agriculture. In this paper will be emphasized practical concepts more crucial for pediatricians.

Tourette syndrome in children and adolescents: special considerations.

PubMed

Eapen, Valsamma; Crncec, Rudi

2009-12-01

Tourette syndrome (TS) affects people of all ages, with onset in early childhood and continuing through the different stages of the life cycle into adolescence and adults. This review focuses on barriers to diagnosis and challenges in the management of young patients with TS. Barriers to identification occur at multiple levels, including detection in the community setting (including schools), parents' help-seeking behavior, and cultural influences on such behavior, as well as diagnosis by the medical provider. Challenges to management include unfamiliarity of primary care providers, inconsistencies in the diagnosis and management plan, and failure to recognize comorbid conditions, as well as inadequate knowledge and lack of resources to effectively deal with comorbidities. In addition to the complexities posed by pharmacological interactions, there are unique psychosocial challenges experienced by young people with TS and their families. Effective communication and collaboration between families, health care providers, and school personnel, as well as supportive communities, are essential components of comprehensive management.

Global Climate Change and the Mitigation Challenge

EPA Science Inventory

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 ...

Combining facial dynamics with appearance for age estimation.

PubMed

Dibeklioglu, Hamdi; Alnajar, Fares; Ali Salah, Albert; Gevers, Theo

2015-06-01

Estimating the age of a human from the captured images of his/her face is a challenging problem. In general, the existing approaches to this problem use appearance features only. In this paper, we show that in addition to appearance information, facial dynamics can be leveraged in age estimation. We propose a method to extract and use dynamic features for age estimation, using a person's smile. Our approach is tested on a large, gender-balanced database with 400 subjects, with an age range between 8 and 76. In addition, we introduce a new database on posed disgust expressions with 324 subjects in the same age range, and evaluate the reliability of the proposed approach when used with another expression. State-of-the-art appearance-based age estimation methods from the literature are implemented as baseline. We demonstrate that for each of these methods, the addition of the proposed dynamic features results in statistically significant improvement. We further propose a novel hierarchical age estimation architecture based on adaptive age grouping. We test our approach extensively, including an exploration of spontaneous versus posed smile dynamics, and gender-specific age estimation. We show that using spontaneity information reduces the mean absolute error by up to 21%, advancing the state of the art for facial age estimation.

Predicting the affinity of Farnesoid X Receptor ligands through a hierarchical ranking protocol: a D3R Grand Challenge 2 case study

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.

A review of cooperative and uncooperative spacecraft pose determination techniques for close-proximity operations

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.

Brazilian Science and Research Integrity: Where are We? What Next?

PubMed

Vasconcelos, Sonia M R; Sorenson, Martha M; Watanabe, Edson H; Foguel, Debora; Palácios, Marisa

2015-01-01

Building a world-class scientific community requires first-class ingredients at many different levels: funding, training, management, international collaborations, creativity, ethics, and an understanding of research integrity practices. All over the world, addressing these practices has been high on the science policy agenda of major research systems. Universities have a central role in fostering a culture of research integrity, which has posed additional challenges for faculty, students and administrators - but also opportunities. In Brazil, the leading universities and governmental funding agencies are collaborating on this project, but much remains to be done.

Providing indigent care: strategic issues in management, marketing and ethics.

PubMed

Summers, J

1986-08-01

Uncompensated cares poses considerable management, marketing and ethical challenges to health care managers. A variety of responses are examined which offer the possibility of reducing the need for inpatient care and the cost of that care as well as for the enhancement of the organization's positioning in the marketing and sales environment. Some of the programs will require support from local community agencies or employers, but others will be quite feasible without such support. Additionally, the programs build on sensitivity to the hospital mission as opposed to turning away from it.

Characterization of quantum well structures using a photocathode electron microscope

NASA Technical Reports Server (NTRS)

Spencer, Michael G.; Scott, Craig J.

1989-01-01

Present day integrated circuits pose a challenge to conventional electronic and mechanical test methods. Feature sizes in the submicron and nanometric regime require radical approaches in order to facilitate electrical contact to circuits and devices being tested. In addition, microwave operating frequencies require careful attention to distributed effects when considering the electrical signal paths within and external to the device under test. An alternative testing approach which combines the best of electrical and optical time domain testing is presented, namely photocathode electron microscope quantitative voltage contrast (PEMQVC).

Femtosecond laser-assisted cataract surgery in pediatric patients.

PubMed

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.

Docking pose selection by interaction pattern graph similarity: application to the D3R grand challenge 2015

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.

CDOCKER and lambda λ -dynamics for prospective prediction in D3R Grand Challenge 2

NASA Astrophysics Data System (ADS)

Ding, Xinqiang; Hayes, Ryan L.; Vilseck, Jonah Z.; Charles, Murchtricia K.; Brooks, Charles L.

2018-01-01

The opportunity to prospectively predict ligand bound poses and free energies of binding to the Farnesoid X Receptor in the D3R Grand Challenge 2 provided a useful exercise to evaluate CHARMM based docking (CDOCKER) and λ-dynamics methodologies for use in "real-world" applications in computer aided drug design. In addition to measuring their current performance, several recent methodological developments have been analyzed retrospectively to highlight best procedural practices in future applications. For pose prediction with CDOCKER, when the protein structure used for rigid receptor docking was close to the crystallographic holo structure, reliable poses were obtained. Benzimidazoles, with a known holo receptor structure, were successfully docked with an average RMSD of 0.97 Å. Other non-benzimidazole ligands displayed less accuracy largely because the receptor structures we chose for docking were too different from the experimental holo structures. However, retrospective analysis has shown that when these ligands were re-docked into their holo structures, the average RMSD dropped to 1.18 Å for all ligands. When sulfonamides and spiros were docked with the apo structure, which agrees more with their holo structure than the structures we chose, five out of six ligands were correctly docked. These docking results emphasize the need for flexible receptor docking approaches. For λ-dynamics techniques, including multisite λ-dynamics (MSλD), reasonable agreement with experiment was observed for the 33 ligands investigated; root mean square errors of 2.08 and 1.67 kcal/mol were obtained for free energy sets 1 and 2, respectively. Retrospectively, soft-core potentials, adaptive landscape flattening, and biasing potential replica exchange (BP-REX) algorithms were critical to model large substituent perturbations with sufficient precision and within restrictive timeframes, such as was required with participation in Grand Challenge 2. These developments, their associated benefits, and proposed procedures for their use in future applications are discussed.

CDOCKER and λ-dynamics for prospective prediction in D₃R Grand Challenge 2.

PubMed

Ding, Xinqiang; Hayes, Ryan L; Vilseck, Jonah Z; Charles, Murchtricia K; Brooks, Charles L

2018-01-01

The opportunity to prospectively predict ligand bound poses and free energies of binding to the Farnesoid X Receptor in the D3R Grand Challenge 2 provided a useful exercise to evaluate CHARMM based docking (CDOCKER) and [Formula: see text]-dynamics methodologies for use in "real-world" applications in computer aided drug design. In addition to measuring their current performance, several recent methodological developments have been analyzed retrospectively to highlight best procedural practices in future applications. For pose prediction with CDOCKER, when the protein structure used for rigid receptor docking was close to the crystallographic holo structure, reliable poses were obtained. Benzimidazoles, with a known holo receptor structure, were successfully docked with an average RMSD of 0.97 [Formula: see text]. Other non-benzimidazole ligands displayed less accuracy largely because the receptor structures we chose for docking were too different from the experimental holo structures. However, retrospective analysis has shown that when these ligands were re-docked into their holo structures, the average RMSD dropped to 1.18 [Formula: see text] for all ligands. When sulfonamides and spiros were docked with the apo structure, which agrees more with their holo structure than the structures we chose, five out of six ligands were correctly docked. These docking results emphasize the need for flexible receptor docking approaches. For [Formula: see text]-dynamics techniques, including multisite [Formula: see text]-dynamics (MS[Formula: see text]D), reasonable agreement with experiment was observed for the 33 ligands investigated; root mean square errors of 2.08 and 1.67 kcal/mol were obtained for free energy sets 1 and 2, respectively. Retrospectively, soft-core potentials, adaptive landscape flattening, and biasing potential replica exchange (BP-REX) algorithms were critical to model large substituent perturbations with sufficient precision and within restrictive timeframes, such as was required with participation in Grand Challenge 2. These developments, their associated benefits, and proposed procedures for their use in future applications are discussed.

Virtual screening of integrase inhibitors by large scale binding free energy calculations: the SAMPL4 challenge

PubMed Central

Gallicchio, Emilio; Deng, Nanjie; He, Peng; Wickstrom, Lauren; Perryman, Alexander L.; Santiago, Daniel N.; Forli, Stefano; Olson, Arthur J.; Levy, Ronald M.

2014-01-01

As part of the SAMPL4 blind challenge, filtered AutoDock Vina ligand docking predictions and large scale binding energy distribution analysis method binding free energy calculations have been applied to the virtual screening of a focused library of candidate binders to the LEDGF site of the HIV integrase protein. The computational protocol leveraged docking and high level atomistic models to improve enrichment. The enrichment factor of our blind predictions ranked best among all of the computational submissions, and second best overall. This work represents to our knowledge the first example of the application of an all-atom physics-based binding free energy model to large scale virtual screening. A total of 285 parallel Hamiltonian replica exchange molecular dynamics absolute protein-ligand binding free energy simulations were conducted starting from docked poses. The setup of the simulations was fully automated, calculations were distributed on multiple computing resources and were completed in a 6-weeks period. The accuracy of the docked poses and the inclusion of intramolecular strain and entropic losses in the binding free energy estimates were the major factors behind the success of the method. Lack of sufficient time and computing resources to investigate additional protonation states of the ligands was a major cause of mispredictions. The experiment demonstrated the applicability of binding free energy modeling to improve hit rates in challenging virtual screening of focused ligand libraries during lead optimization. PMID:24504704

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...

Security, development and human rights: normative, legal and policy challenges for the international drug control system.

PubMed

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.

Comprehensive strategies for the prevention and control of diabetes and cardiovascular diseases in Africa: future directions.

PubMed

Muna, Walinjom F T

2013-01-01

The countries of the Sub Saharan African region have insufficient resources and healthcare systems that are poorly adapted to cope with the longstanding burden associated with communicable diseases and the ongoing HIV/AIDS pandemic. In addition, the rising burden of non-communicable diseases, including diabetes, cardiovascular diseases, and their risk factors, poses additional challenges. These countries need to urgently develop strategies to address these challenges of disease prevention and control. These strategies will require a new vision and more relevant and 'suitable' vocabulary in dealing with healthcare design, planning and implementation (using a cross-sectorial approach). Lessons learnt from the past (e.g. primary health care) in sub-Saharan Africa and other regions of the world may equally prove useful in developing strategies for the prevention and control of non-communicable diseases. Any potential strategy must emphasize the crucial role of economic, social, and environmental health determinants as well as the use of appropriate health technology. © 2013.

[Evaluative designs in public health: methodological considerations].

PubMed

López, Ma José; Marí-Dell'Olmo, Marc; Pérez-Giménez, Anna; Nebot, Manel

2011-06-01

Evaluation of public health interventions poses numerous methodological challenges. Randomization of individuals is not always feasible and interventions are usually composed of multiple factors. To face these challenges, certain elements, such as the selection of the most appropriate design and the use of a statistical analysis that includes potential confounders, are essential. The objective of this article was to describe the most frequently used designs in the evaluation of public health interventions (policies, programs or campaigns). The characteristics, strengths and weaknesses of each of these evaluative designs are described. Additionally, a brief explanation of the most commonly used statistical analysis in each of these designs is provided. Copyright © 2011 Sociedad Española de Salud Pública y Administración Sanitaria. Published by Elsevier Espana. All rights reserved.

Access and Costs: Recommendations for Title IV. Hearing on Examining Proposals Authorizing Funds for Title IV Student Aid Programs and Issues Relating to Access to Costs of Postsecondary Education of the Higher Education Act, Including S. 1036, To Revise Section 435 of the Higher Education Act To Allow for the Young Americans Bank and Similar Small, Nonprofit Organizations to Provide Additional Funds for Educational Programming, of the Committee on Labor and Human Resources. United States Senate, One Hundred Fifth Congress, First Session.

ERIC Educational Resources Information Center

Congress of the U.S., Washington, DC. Senate Committee on Labor and Human Resources.

This 10th and final hearing in a series related to the reauthorization of the Higher Education Act, focused on three specific areas: (1) the challenges posed by demographic changes in the college student population--nearly half of all students attend community colleges where the average age of students is 29; (2) the challenges and opportunities…

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)

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.

A non-conventional discontinuous Lagrangian for viscous flow

PubMed Central

Marner, F.

2017-01-01

Drawing an analogy with quantum mechanics, a new Lagrangian is proposed for a variational formulation of the Navier–Stokes equations which to-date has remained elusive. A key feature is that the resulting Lagrangian is discontinuous in nature, posing additional challenges apropos the mathematical treatment of the related variational problem, all of which are resolvable. In addition to extending Lagrange's formalism to problems involving discontinuous behaviour, it is demonstrated that the associated equations of motion can self-consistently be interpreted within the framework of thermodynamics beyond local equilibrium, with the limiting case recovering the classical Navier–Stokes equations. Perspectives for applying the new formalism to discontinuous physical phenomena such as phase and grain boundaries, shock waves and flame fronts are provided. PMID:28386415

A non-conventional discontinuous Lagrangian for viscous flow.

PubMed

Scholle, M; Marner, F

2017-02-01

Drawing an analogy with quantum mechanics, a new Lagrangian is proposed for a variational formulation of the Navier-Stokes equations which to-date has remained elusive. A key feature is that the resulting Lagrangian is discontinuous in nature, posing additional challenges apropos the mathematical treatment of the related variational problem, all of which are resolvable. In addition to extending Lagrange's formalism to problems involving discontinuous behaviour, it is demonstrated that the associated equations of motion can self-consistently be interpreted within the framework of thermodynamics beyond local equilibrium, with the limiting case recovering the classical Navier-Stokes equations. Perspectives for applying the new formalism to discontinuous physical phenomena such as phase and grain boundaries, shock waves and flame fronts are provided.

Measuring calcium dynamics in living cells with Genetically Encodable Calcium Indicators

PubMed Central

McCombs, Janet E.

2008-01-01

Genetically encoded calcium indicators (GECIs) allow researchers to measure calcium dynamics in specific targeted locations within living cells. Such indicators enable dissection of the spatial and temporal control of calcium signaling processes. Here we review recent progress in the development of GECIs, highlighting which indicators are most appropriate for measuring calcium in specific organelles and localized domains in mammalian tissue culture cells. An overview of recent approaches that have been undertaken to ensure that the GECIs are minimally perturbed by the cellular environment is provided. Additionally, the procedures for introducing GECIs into mammalian cells, conducting calcium imaging experiments, and analyzing data are discussed. Because organelle-targeted indicators often pose an additional challenge, we underscore strategies for calibrating GECIs in these locations. PMID:18848629

D3R Grand Challenge 2: blind prediction of protein-ligand poses, affinity rankings, and relative binding free energies

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.

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…

Stabilization of Proteins and Noncovalent Protein Complexes during Electrospray Ionization by Amino Acid Additives.

PubMed

Zhang, Hua; Lu, Haiyan; Chingin, Konstantin; Chen, Huanwen

2015-07-21

Ionization of proteins and noncovalent protein complexes with minimal disturbance to their native structure presents a great challenge for biological mass spectrometry (MS). In living organisms, the native structure of intracellular proteins is commonly stabilized by solute amino acids (AAs) accumulated in cells at very high concentrations. Inspired by nature, we hypothesized that AAs could also pose a stabilizing effect on the native structure of proteins and noncovalent protein complexes during ionization. To test this hypothesis, here we explored MS response for various protein complexes upon the addition of free AAs at mM concentrations into the electrospray ionization (ESI) solution. Thermal activation of ESI droplets in the MS inlet capillary was employed as a model destabilizing factor during ionization. Our results indicate that certain AAs, in particular proline (Pro), pose considerable positive effect on the stability of noncovalent protein complexes in ESI-MS without affecting the signal intensity of protein ions and original protein-ligand equilibrium, even when added at the 20 mM concentration. The data suggest that the degree of protein stabilization is primarily determined by the osmolytic and ampholytic characteristics of AA solutes. The highest stability and visibility of noncovalent protein complexes in ESI-MS are achieved using AA additives with neutral isoelectric point, moderate proton affinity, and unfavorable interaction with the native protein state. Overall, our results indicate that the simple addition of free amino acids into the working solution can notably improve the stability and accuracy of protein analysis by native ESI-MS.

The Marihuana Dilemma: Challenge to Commanders.

DTIC Science & Technology

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…

Transforming Teaching Challenges into Learning Opportunities: Interdisciplinary Reflective Collaboration

ERIC Educational Resources Information Center

Callaghan, Ronel

2015-01-01

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

Hydrodynamics of wet foams

NASA Astrophysics Data System (ADS)

Langevin, Dominique; Saint-Jalmes, Arnaud; Marze, Sébastien; Cox, Simon; Hutzler, Stefan; Drenckhan, Wiebke; Weaire, Denis; Caps, Hervé; Vandewalle, Nicolas; Adler, Micheàle; Pitois, Olivier; Rouyer, Florence; Cohen-Addad, Sylvie; Höhler, Reinhard; Ritacco, Hernan

2005-10-01

Foams and foaming pose important questions and problems to the chemical industry. As a material, foam is unusual in being a desired product while also being an unwanted byproduct within industry. Liquid foams are an essential part of gas/liquid contacting processes such as distillation and absorption, but over-production of foam in these processes can lead to downtime and loss of efficiency. Solid polymeric foams, such as polystyrene and polyurethane, find applications as insulation panels in the construction industry. Their combination of low weight and unique elastic/plastic properties make them ideal as packing and cushioning materials. Foams made with proteins are extensively used in the food industry. Despite the fact that foam science is a rapidly maturing field, critical aspects of foam physics and chemistry remain unclear. Several gaps in knowledge were identified to be tackled as the core of this MAP project. In addition, microgravity affords conditions for extending our understanding far beyond the possibilities offered by ground-based investigation. This MAP project addresses the challenges posed by the physics of foams under microgravity.

NSLS-II beamline scattered gas bremsstrahlung radiation shielding calculation

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

Popescu, Razvan; Xia, Zhenghua, E-mail: xiazhenghuacn@hotmail.com; Job, Panakkal

2016-07-27

National Synchrotron Light Source II (NSLS-II) is a new state-of-the-art 3rd generation synchrotron. The NSLS-II facility is shielded up to 3 GeV electron beam energy at 500 mA. When the gas bremsstrahlung (GB) from the storage ring is scattered by the beamline components in the first optical enclosure (FOE), the scattered radiation will pose additional radiation hazard (bypassing primary GB collimators and stops) and challenge the FOE shielding. The scattered GB radiation hazard can be mitigated by supplementary shielding or with an exclusion zone downstream of the FOE.

Mass Property Measurements of the Mars Science Laboratory Rover

NASA Technical Reports Server (NTRS)

Fields, Keith

2012-01-01

The NASA/JPL Mars Science Laboratory (MSL) spacecraft mass properties were measured on a spin balance table prior to launch. This paper discusses the requirements and issues encountered with the setup, qualification, and testing using the spin balance table, and the idiosyncrasies encountered with the test system. The final mass measurements were made in the Payload Hazardous Servicing Facility (PHSF) at Kennedy Space Center on the fully assembled and fueled spacecraft. This set of environmental tests required that the control system for the spin balance machine be at a remote location, which posed additional challenges to the operation of the machine

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.

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.

Docking pose selection by interaction pattern graph similarity: application to the D3R grand challenge 2015.

PubMed

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.

Regulation of animal biotechnology: research needs.

PubMed

Rexroad, C E; Green, R D; Wall, R J

2007-09-01

Livestock that result from biotechnology have been a part of agricultural science for over 30 years but have not entered the market place as food or fiber. Two biotechnologies are at the forefront as challenges to the world's systems for regulating the market place: animal clones and transgenic animals. Both technologies have come before the Food and Drug Administration in the United States and it appears that action is imminent for clones. The FDA has asserted principles for evaluation of clones and asserts that "... remaining hazard(s) from cloning are likely to be subtle in nature." The science-based principles recognize that in some areas related to developmental biology and gene expression in clones, additional scientific information would be useful. The role of science then is to use the genomic tools that we have available to answer questions about epigenetic regulation of development and reprogramming of genes to the state found in germ cells. Transgenics pose additional challenges to regulators. If the transgenics are produced using cloning from modified cells then the additional scientific information needed will be related to the effects of insertion and expression of the transgenes. Other approaches such as retrovirally vectored transgenesis will elicit additional questions. These questions will be challenging because the science will have to be related to the expression and function of each gene or class of genes. For the promises of animal biotechnology to be fulfilled, scientists will have to resolve many questions for regulators and the public but tools to answer those questions are rapidly becoming available.

Head pose estimation in computer vision: a survey.

PubMed

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.

PubMed

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.

Ethical and professional challenges posed by patients with genetic concerns: a report of focus group discussions with genetic counselors, physicians, and nurses.

PubMed

Veach, P M; Bartels, D M; LeRoy, B S

2001-04-01

Ninety-seven physicians, nurses, and genetic counselors from four regions within the United States participated in focus groups to identify the types of ethical and professional challenges that arise when their patients have genetic concerns. Responses were taped and transcribed and then analyzed using the Hill et al. (1997, Counsel Psychol 25:517-522) Consensual Qualitative Research method of analysis. Sixteen major ethical and professional domains and 63 subcategories were identified. Major domains are informed consent; withholding information; facing uncertainty; resource allocation; value conflicts, directiveness/nondirectiveness; determining the primary patient; professional identity issues; emotional responses; diversity issues; confidentiality; attaining/maintaining proficiency; professional misconduct; discrimination; colleague error; and documentation. Implications for practitioners who deal with genetic issues and recommendations for additional research are given.

Health care reform in the new South Africa.

PubMed

Benatar, S R

1997-03-20

The social transition which must follow the political transition in South Africa will pose major challenges for many decades. While it clear that inequities must be reduced, it is less clear how to effectively and sustainably achieve that end, especially given current rapid population growth and minimal additional resources in an economy which is growing less rapidly than hoped for by the new government. Health care reform is one of the country's many challenges. This paper provides insight into the shift from the conventional biomedical model of health care to the primary health care approach within a fixed public health budget. Obstacles to change, threats to academic activities, the 1980s and 1990s, political and social transition, health care reform since 1994, academic medicine and medical education, choices facing society, movement from political apartheid to economic apartheid, and public awareness are described.

Bench-to-bedside review: The MET syndrome – the challenges of researching and adopting medical emergency teams

PubMed Central

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

Orion EFT-1 Cavity Heating Tile Experiments and Environment Reconstruction

NASA Technical Reports Server (NTRS)

Salazar, Giovanni; Amar, Adam; Oliver, Brandon; Hyatt, Andrew; Rezin, Marc

2016-01-01

Developing aerothermodynamic environments for deep cavities, such as those produced by micrometeoroids and orbital debris impacts, poses a great challenge for engineers. In order to assess existing cavity heating models, two one-inch diameter cavities were flown on the Orion Multi-Purpose Crew Vehicle during Exploration Flight Test 1 (EFT1). These cavities were manufactured with depths of 1.0 in and 1.4 in, and they were both instrumented. Instrumentation included surface thermocouples upstream, downstream and within the cavities, and additional thermocouples at the TPS-structure interface. This paper will present the data obtained, and comparisons with computational predictions will be shown. Additionally, the development of a 3D material thermal model will be described, which will be used to account for the three-dimensionality of the problem when interpreting the data. Furthermore, using a multi-dimensional inverse heat conduction approach, a reconstruction of a time- and space-dependent flight heating distribution during EFT1 will be presented. Additional discussions will focus on instrumentation challenges and calibration techniques specific to these experiments. The analysis shown will highlight the accuracies and/or deficiencies of current computational techniques to model cavity flows during hypersonic re-entry.

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.

KSC-2012-1545

NASA Image and Video Library

2012-02-23

ORLANDO, Fla. -- The winners of NASA’s Quality and Safety Achievement Recognition, or QASAR, awards for 2011 pose for a group portrait during NASA’s ninth annual Project Management Challenge. From left are Teri Hamlin, Johnson Space Center Joseph B. Hamilton, Kennedy Space Center Francis “Frank” Merceret, Kennedy Space Center and Venki Venkat, Langley Research Center. Kennedy retiree Humberto "Bert" T. Garrido, not pictured, also received the award. NASA's QASAR award recognizes individual government and contractor employees who have demonstrated exemplary performance in contributing to the quality or safety of products, services, processes, or management programs and activities. PM Challenge 2012 was held at the Caribe Royale Hotel and Convention Center in Orlando, Fla., on February 22-23, to provide a forum for all stakeholders in the project management community to meet and share stories, lessons learned and new uses of technology in the industry. The PM Challenge is sponsored by NASA's Office of the Chief Engineer. For additional information, visit http://www.nasa.gov/offices/oce/pmchallenge/index.html. Photo credit: NASA/Jim Grossmann

Stock assessment in inland fisheries: a foundation for sustainable use and conservation

USGS Publications Warehouse

Lorenzen, Kai; Cowx, Ian G.; Entsua-Mensah, R. E. M.; Lester, Nigel P.; Koehn, J.D.; Randall, R.G.; So, N.; Bonar, Scott A.; Bunnell, David B.; Venturelli, Paul A.; Bower, Shannon D.; Cooke, Steven J.

2016-01-01

Fisheries stock assessments are essential for science-based fisheries management. Inland fisheries pose challenges, but also provide opportunities for biological assessments that differ from those encountered in large marine fisheries for which many of our assessment methods have been developed. These include the number and diversity of fisheries, high levels of ecological and environmental variation, and relative lack of institutional capacity for assessment. In addition, anthropogenic impacts on habitats, widespread presence of non-native species and the frequent use of enhancement and restoration measures such as stocking affect stock dynamics. This paper outlines various stock assessment and data collection approaches that can be adapted to a wide range of different inland fisheries and management challenges. Although this paper identifies challenges in assessment, it focuses on solutions that are practical, scalable and transferrable. A path forward is suggested in which biological assessment generates some of the critical information needed by fisheries managers to make effective decisions that benefit the resource and stakeholders.

Communicating about smoke from wildland fire: challenges and ways to address them

Treesearch

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…

A Problem Posing-Based Practicing Strategy for Facilitating Students' Computer Programming Skills in the Team-Based Learning Mode

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…

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.

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...

The Challenge of Teacher Retention in Urban Schools: Evidence of Variation from a Cross-Site Analysis

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

PubMed Central

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

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.

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.

The study of direct-to-consumer advertising for prescription drugs.

PubMed

Schommer, Jon C; Hansen, Richard A

2005-06-01

The objectives of this article are to (1) identify key methodological issues related to investigating the effects of direct-to-consumer advertising (DTCA) for prescription drugs, (2) highlight opportunities and challenges that these issues pose, and (3) provide suggestions to address these challenges and opportunities from a social and administrative pharmacy perspective. Through a review of existing literature and consultation with research colleagues, we identified 3 broad issues regarding the study of DTCA for prescription drugs: (1) the importance of problem formulation, (2) the role of health behavior and decision-making perspectives, and (3) data collection and data analysis challenges and opportunities. Based upon our findings, we developed recommendations for future research in this area. Clear problem formulation will be instructive for prioritizing research needs and for determining the role that health behavior and decision-making perspectives can serve in DTCA research. In addition, it appears that cluster bias, nonlinear relationships, mediating/moderating effects, time effects, acquiescent response, and case mix are particularly salient challenges for the DTCA research domain. We suggest that problem formulation, selection of sound theories upon which to base research, and data collection and data analysis challenges are key methodological issues related to investigating the effects of DTCA for prescription drugs.

Access and acceptability of community-based services for older Greek migrants in Australia: user and provider perspectives.

PubMed

Hurley, Catherine; Panagiotopoulos, Georgia; Tsianikas, Michael; Newman, Lareen; Walker, Ruth

2013-03-01

In most developed nations, ageing migrants represent a growing proportion of the older population. Policies that emphasise care in the community depend on older migrants having access to formal services along with informal support, yet little is known about how older migrants experience community-based formal services. By examining the views of both Greek elders in Australia and those of formal service providers, this research fills an important gap in the literature around access to and acceptability of formal community-based services for older migrants. A research team including two Greek background researchers used existing social groups and a snowball sampling method to conduct face-to-face interviews and focus groups with seventy older Greeks in Adelaide, Australia. In addition, 22 community-based service providers were interviewed over the telephone. Results from users and providers showed that while many older Greeks experience service access issues, they also relied heavily on family for support and assistance at home. Reliance on family was both in preference to formal services or where formal services were used, to locate, negotiate and monitor such services. Common barriers identified by both groups included cost, transport and availability, but additional challenges were posed by language, literacy and cultural attitudes. Demographic changes including greater employment mobility and female workforce participation among adult children will have implications for both formal and informal care providers. Formal service providers need to ensure that services are promoted and delivered to take account of the important role of family in informal support while also addressing the access challenges posed by language and literacy. Research conducted by researchers from the same cultural background in the respondent's native language can further advance knowledge in this area. © 2012 Blackwell Publishing Ltd.

RECRUITMENT STRATEGIES FOR AN EXPOSURE MEASUREMENT STUDY OF PRESCHOOL CHILDREN

EPA Science Inventory

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 ...

Sustainable Materials Management (SMM) Web Academy Webinar: Management Challenges for Lithium Batteries at Electronics Recyclers

EPA Pesticide Factsheets

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.

Curriculum Integration: Helping Career and Technical Education Students Truly Develop College and Career Readiness

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

DTIC Science & Technology

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

Additive Manufacturing: Unlocking the Evolution of Energy Materials

PubMed Central

Zhakeyev, Adilet; Wang, Panfeng; Shu, Wenmiao; Wang, Huizhi

2017-01-01

Abstract The global energy infrastructure is undergoing a drastic transformation towards renewable energy, posing huge challenges on the energy materials research, development and manufacturing. Additive manufacturing has shown its promise to change the way how future energy system can be designed and delivered. It offers capability in manufacturing complex 3D structures, with near‐complete design freedom and high sustainability due to minimal use of materials and toxic chemicals. Recent literatures have reported that additive manufacturing could unlock the evolution of energy materials and chemistries with unprecedented performance in the way that could never be achieved by conventional manufacturing techniques. This comprehensive review will fill the gap in communicating on recent breakthroughs in additive manufacturing for energy material and device applications. It will underpin the discoveries on what 3D functional energy structures can be created without design constraints, which bespoke energy materials could be additively manufactured with customised solutions, and how the additively manufactured devices could be integrated into energy systems. This review will also highlight emerging and important applications in energy additive manufacturing, including fuel cells, batteries, hydrogen, solar cell as well as carbon capture and storage. PMID:29051861

Additive Manufacturing: Unlocking the Evolution of Energy Materials.

PubMed

Zhakeyev, Adilet; Wang, Panfeng; Zhang, Li; Shu, Wenmiao; Wang, Huizhi; Xuan, Jin

2017-10-01

The global energy infrastructure is undergoing a drastic transformation towards renewable energy, posing huge challenges on the energy materials research, development and manufacturing. Additive manufacturing has shown its promise to change the way how future energy system can be designed and delivered. It offers capability in manufacturing complex 3D structures, with near-complete design freedom and high sustainability due to minimal use of materials and toxic chemicals. Recent literatures have reported that additive manufacturing could unlock the evolution of energy materials and chemistries with unprecedented performance in the way that could never be achieved by conventional manufacturing techniques. This comprehensive review will fill the gap in communicating on recent breakthroughs in additive manufacturing for energy material and device applications. It will underpin the discoveries on what 3D functional energy structures can be created without design constraints, which bespoke energy materials could be additively manufactured with customised solutions, and how the additively manufactured devices could be integrated into energy systems. This review will also highlight emerging and important applications in energy additive manufacturing, including fuel cells, batteries, hydrogen, solar cell as well as carbon capture and storage.

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…

When Bible and Science Interact: Teachers' Pedagogic and Value Challenges in Teaching Religious Minority Students in Higher Education Settings

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…

Testing Scientific Software: A Systematic Literature Review.

PubMed

Kanewala, Upulee; Bieman, James M

2014-10-01

Scientific software plays an important role in critical decision making, for example making weather predictions based on climate models, and computation of evidence for research publications. Recently, scientists have had to retract publications due to errors caused by software faults. Systematic testing can identify such faults in code. This study aims to identify specific challenges, proposed solutions, and unsolved problems faced when testing scientific software. We conducted a systematic literature survey to identify and analyze relevant literature. We identified 62 studies that provided relevant information about testing scientific software. We found that challenges faced when testing scientific software fall into two main categories: (1) testing challenges that occur due to characteristics of scientific software such as oracle problems and (2) testing challenges that occur due to cultural differences between scientists and the software engineering community such as viewing the code and the model that it implements as inseparable entities. In addition, we identified methods to potentially overcome these challenges and their limitations. Finally we describe unsolved challenges and how software engineering researchers and practitioners can help to overcome them. Scientific software presents special challenges for testing. Specifically, cultural differences between scientist developers and software engineers, along with the characteristics of the scientific software make testing more difficult. Existing techniques such as code clone detection can help to improve the testing process. Software engineers should consider special challenges posed by scientific software such as oracle problems when developing testing techniques.

The Addition of Medium-Chain Triglycerides to a Purified Fish Oil Based Diet Alters Inflammatory Profiles in Mice

PubMed Central

Carlson, SJ; Nandivada, P; Chang, MI; Mitchell, PD; O’Loughlin, A; Cowan, E; Gura, KM; Nose, V; Bistrian, B; Puder, M

2014-01-01

Objective Parenteral nutrition associated liver disease (PNALD) is a deadly complication of long term parenteral nutrition (PN) use in infants. Fish oil-based lipid emulsion has been shown in recent years to effectively treat PNALD. Alternative fat sources free of essential fatty acids have recently been investigated for health benefits related to decreased inflammatory response. We hypothesized that the addition of medium-chain triglycerides (MCT) to a purified fish oil-based diet would decrease the response to inflammatory challenge in mice, while allowing for sufficient growth and development. Materials/Methods Six groups of ten adult male C57/Bl6 mice were pair-fed different dietary treatments for a period of twelve weeks, varying only in fat source (percent calories by weight): 10.84% soybean oil (SOY), 10% coconut oil (HCO), 10% medium-chain triglycerides (MCT), 3% purified fish oil (PFO), 3% purified fish oil with 3% medium-chain triglycerides (50:50 MCT:PFO) and 3% purified fish oil with 7.59% medium-chain triglycerides (70:30 MCT:PFO). An endotoxin challenge was administered to half of the animals in each group at the completion of dietary treatment. Results All groups demonstrated normal growth throughout the study period. Groups fed MCT and HCO diets demonstrated biochemical essential fatty acid deficiency and decreased IL-6 and TNF-α response to endotoxin challenge. Groups containing PFO had increased inflammatory response to endotoxin challenge, and the addition of MCT to PFO mitigated this inflammatory response. Conclusion These results suggest that the addition of MCT to PFO formulations may decrease the host response to inflammatory challenge, which may pose potential for optimized PN formulations. Inclusion of MCT in lipid emulsions given with PN formulations may be of use in therapeutic interventions for disease states resulting from chronic inflammation. PMID:25458829

The addition of medium-chain triglycerides to a purified fish oil-based diet alters inflammatory profiles in mice.

PubMed

Carlson, Sarah J; Nandivada, Prathima; Chang, Melissa I; Mitchell, Paul D; O'Loughlin, Alison; Cowan, Eileen; Gura, Kathleen M; Nose, Vania; Bistrian, Bruce R; Puder, Mark

2015-02-01

Parenteral nutrition associated liver disease (PNALD) is a deadly complication of long term parenteral nutrition (PN) use in infants. Fish oil-based lipid emulsion has been shown in recent years to effectively treat PNALD. Alternative fat sources free of essential fatty acids have recently been investigated for health benefits related to decreased inflammatory response. We hypothesized that the addition of medium-chain triglycerides (MCT) to a purified fish oil-based diet would decrease the response to inflammatory challenge in mice, while allowing for sufficient growth and development. Six groups of ten adult male C57/Bl6 mice were pair-fed different dietary treatments for a period of twelve weeks, varying only in fat source (percent calories by weight): 10.84% soybean oil (SOY), 10% coconut oil (HCO), 10% medium-chain triglycerides (MCT), 3% purified fish oil (PFO), 3% purified fish oil with 3% medium-chain triglycerides (50:50 MCT:PFO) and 3% purified fish oil with 7.59% medium-chain triglycerides (70:30 MCT:PFO). An endotoxin challenge was administered to half of the animals in each group at the completion of dietary treatment. All groups demonstrated normal growth throughout the study period. Groups fed MCT and HCO diets demonstrated biochemical essential fatty acid deficiency and decreased IL-6 and TNF-α response to endotoxin challenge. Groups containing PFO had increased inflammatory response to endotoxin challenge, and the addition of MCT to PFO mitigated this inflammatory response. These results suggest that the addition of MCT to PFO formulations may decrease the host response to inflammatory challenge, which may pose potential for optimized PN formulations. Inclusion of MCT in lipid emulsions given with PN formulations may be of use in therapeutic interventions for disease states resulting from chronic inflammation. Copyright © 2015 Elsevier Inc. All rights reserved.

The Real Challenge of ESD

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

EPA Science Inventory

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...

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.

PubMed

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.

[Principles of intervertebral disc assessment in private accident insurance].

PubMed

Steinmetz, M; Dittrich, V; Röser, K

2015-09-01

Due to the spread of intervertebral disc degeneration, insurance companies and experts are regularly confronted with related assessments of insured persons under their private accident insurance. These claims pose a particular challenge for experts, since, in addition to the clinical assessment of the facts, extensive knowledge of general accident insurance conditions, case law and current study findings is required. Each case can only be properly assessed through simultaneous consideration of both the medical and legal facts. These guidelines serve as the basis for experts and claims.managers with respect to the appropriate individual factual assessment of intervertebral disc degeneration in private accident insurance.

Management of Gout and Hyperuricemia in CKD.

PubMed

Vargas-Santos, Ana Beatriz; Neogi, Tuhina

2017-09-01

Hyperuricemia and gout, the clinical manifestation of monosodium urate crystal deposition, are common in patients with chronic kidney disease (CKD). Although the presence of CKD poses additional challenges in gout management, effective urate lowering is possible for most patients with CKD. Initial doses of urate-lowering therapy are lower than in the non-CKD population, whereas incremental dose escalation is guided by regular monitoring of serum urate levels to reach the target level of <6mg/dL (or <5mg/dL for patients with tophi). Management of gout flares with presently available agents can be more challenging due to potential nephrotoxicity and/or contraindications in the setting of other common comorbid conditions. At present, asymptomatic hyperuricemia is not an indication for urate-lowering therapy, though emerging data may support a potential renoprotective effect. Copyright © 2017 National Kidney Foundation, Inc. Published by Elsevier Inc. 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.

The Diabetic foot: A global threat and a huge challenge for Greece

PubMed Central

Papanas, N; Maltezos, E

2009-01-01

The diabetic foot continues to be a major cause of morbidity, posing a global threat. Substantial progress has been now accomplished in the treatment of foot lesions, but further improvement is required. Treatment options may be classified into established measures (revascularisation, casting and debridement) and new modalities. All therapeutic measures should be provided by specialised dedicated multidisciplinary foot clinics. In particular, the diabetic foot is a huge challenge for Greece. There is a dramatic need to increase the number of engaged foot care teams and their resources throughout the country. It is also desirable to continue education of both physicians and general diabetic population on the magnitude of the problem and on the suitable preventative measures. At the same time, more data on the prevalence and clinical manifestations of the diabetic foot in Greece should be carefully collected. Finally, additional research should investigate feasible ways of implementing current knowledge in everyday clinical practice. PMID:20011082

ParaBTM: A Parallel Processing Framework for Biomedical Text Mining on Supercomputers.

PubMed

Xing, Yuting; Wu, Chengkun; Yang, Xi; Wang, Wei; Zhu, En; Yin, Jianping

2018-04-27

A prevailing way of extracting valuable information from biomedical literature is to apply text mining methods on unstructured texts. However, the massive amount of literature that needs to be analyzed poses a big data challenge to the processing efficiency of text mining. In this paper, we address this challenge by introducing parallel processing on a supercomputer. We developed paraBTM, a runnable framework that enables parallel text mining on the Tianhe-2 supercomputer. It employs a low-cost yet effective load balancing strategy to maximize the efficiency of parallel processing. We evaluated the performance of paraBTM on several datasets, utilizing three types of named entity recognition tasks as demonstration. Results show that, in most cases, the processing efficiency can be greatly improved with parallel processing, and the proposed load balancing strategy is simple and effective. In addition, our framework can be readily applied to other tasks of biomedical text mining besides NER.

A component-based software environment for visualizing large macromolecular assemblies.

PubMed

Sanner, Michel F

2005-03-01

The interactive visualization of large biological assemblies poses a number of challenging problems, including the development of multiresolution representations and new interaction methods for navigating and analyzing these complex systems. An additional challenge is the development of flexible software environments that will facilitate the integration and interoperation of computational models and techniques from a wide variety of scientific disciplines. In this paper, we present a component-based software development strategy centered on the high-level, object-oriented, interpretive programming language: Python. We present several software components, discuss their integration, and describe some of their features that are relevant to the visualization of large molecular assemblies. Several examples are given to illustrate the interoperation of these software components and the integration of structural data from a variety of experimental sources. These examples illustrate how combining visual programming with component-based software development facilitates the rapid prototyping of novel visualization tools.

Exotic encounters with dental implants: managing complications with unidentified systems.

PubMed

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.

Trojan Horse Antibiotics—A Novel Way to Circumvent Gram-Negative Bacterial Resistance?

PubMed Central

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?

PubMed

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.

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…

Challenges for PISA

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…

Challenges of Conducting Research With Young Offenders With Traumatic Brain Injury.

PubMed

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.

Bisphenol A and Risk Management Ethics

PubMed Central

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.

PubMed

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.

The challenges associated with developing science-based landscape scale management plans.

Treesearch

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...

International Olympic Committee consensus statement on thermoregulatory and altitude challenges for high-level athletes.

PubMed

Bergeron, M F; Bahr, R; Bärtsch, P; Bourdon, L; Calbet, J A L; Carlsen, K H; Castagna, O; González-Alonso, J; Lundby, C; Maughan, R J; Millet, G; Mountjoy, M; Racinais, S; Rasmussen, P; Singh, D G; Subudhi, A W; Young, A J; Soligard, T; Engebretsen, L

2012-09-01

Challenging environmental conditions, including heat and humidity, cold, and altitude, pose particular risks to the health of Olympic and other high-level athletes. As a further commitment to athlete safety, the International Olympic Committee (IOC) Medical Commission convened a panel of experts to review the scientific evidence base, reach consensus, and underscore practical safety guidelines and new research priorities regarding the unique environmental challenges Olympic and other international-level athletes face. For non-aquatic events, external thermal load is dependent on ambient temperature, humidity, wind speed and solar radiation, while clothing and protective gear can measurably increase thermal strain and prompt premature fatigue. In swimmers, body heat loss is the direct result of convection at a rate that is proportional to the effective water velocity around the swimmer and the temperature difference between the skin and the water. Other cold exposure and conditions, such as during Alpine skiing, biathlon and other sliding sports, facilitate body heat transfer to the environment, potentially leading to hypothermia and/or frostbite; although metabolic heat production during these activities usually increases well above the rate of body heat loss, and protective clothing and limited exposure time in certain events reduces these clinical risks as well. Most athletic events are held at altitudes that pose little to no health risks; and training exposures are typically brief and well-tolerated. While these and other environment-related threats to performance and safety can be lessened or averted by implementing a variety of individual and event preventative measures, more research and evidence-based guidelines and recommendations are needed. In the mean time, the IOC Medical Commission and International Sport Federations have implemented new guidelines and taken additional steps to mitigate risk even further.

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…

THE DNAPL REMEDIATION CHALLENGE: IS THERE A CASE FOR SOURCE DEPLETION?

EPA Science Inventory

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 ...

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…

LIFE CYCLE ASSESSMENT (LCA) AS A FRAMEWORK FOR ADDRESSING THE SUSTAINABILITY OF CONCENTRATED ANIMAL FEEDING OPERATIONS (CAFOS)

EPA Science Inventory

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)

Ligand-biased ensemble receptor docking (LigBEnD): a hybrid ligand/receptor structure-based approach

NASA Astrophysics Data System (ADS)

Lam, Polo C.-H.; Abagyan, Ruben; Totrov, Maxim

2018-01-01

Ligand docking to flexible protein molecules can be efficiently carried out through ensemble docking to multiple protein conformations, either from experimental X-ray structures or from in silico simulations. The success of ensemble docking often requires the careful selection of complementary protein conformations, through docking and scoring of known co-crystallized ligands. False positives, in which a ligand in a wrong pose achieves a better docking score than that of native pose, arise as additional protein conformations are added. In the current study, we developed a new ligand-biased ensemble receptor docking method and composite scoring function which combine the use of ligand-based atomic property field (APF) method with receptor structure-based docking. This method helps us to correctly dock 30 out of 36 ligands presented by the D3R docking challenge. For the six mis-docked ligands, the cognate receptor structures prove to be too different from the 40 available experimental Pocketome conformations used for docking and could be identified only by receptor sampling beyond experimentally explored conformational subspace.

The Potential of Statement-Posing Tasks

ERIC Educational Resources Information Center

Yang, Kai-Lin

2010-01-01

This communication aims at revealing the potential of statement-posing tasks to facilitate students' thinking and strategies of understanding proof. Besides outlining the background of statement-posing tasks, four points were advanced as potential benefits of the tasks: (1) focusing on the logic of arguments in addition to the meaning of…

Exploration Design Challenge 2014

NASA Image and Video Library

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

NASA Image and Video Library

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)

The real challenges: the orphan generation and employment creation.

PubMed

Whiteside, A

2000-01-01

A baby born to an HIV-positive mother has close to a 100% chance of being orphaned before reaching the age of 10. In South Africa, nearly 1 million children under the age of 15 are projected to lose their mothers by 2005 due to AIDS. These orphans are less likely to receive adequate parenting, education, and nutrition; others will seek to survive on the streets and thus will be more likely to face sexual abuse and exploitation. The long-term impact of HIV/AIDS on both the children and society will be severe. The orphans that AIDS is creating pose serious social, economic, political, and developmental challenges for South Africa. There are two options left for the government: 1) dramatically increasing welfare grants and staffing of welfare departments in order to care for the orphans; 2) find new imaginative measures of meeting the challenge. In addition, provision of employment for its population is another challenge the region is facing. Having the required resources and infrastructure, a potential intervention for South Africa would be training and employing a new cadre of workers to care for AIDS orphans. This type of response would also help build a civil society.

Food Aversions and Cravings during Pregnancy on Yasawa Island, Fiji.

PubMed

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.

PubMed

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.

The future water environment--using scenarios to explore the significant water management challenges in England and Wales to 2050.

PubMed

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.

NASA Space Rocket Logistics Challenges

NASA Technical Reports Server (NTRS)

Neeley, James R.; Jones, James V.; Watson, Michael D.; Bramon, Christopher J.; Inman, Sharon K.; Tuttle, Loraine

2014-01-01

The Space Launch System (SLS) is the new NASA heavy lift launch vehicle and is scheduled for its first mission in 2017. The goal of the first mission, which will be uncrewed, is to demonstrate the integrated system performance of the SLS rocket and spacecraft before a crewed flight in 2021. SLS has many of the same logistics challenges as any other large scale program. Common logistics concerns for SLS include integration of discreet programs geographically separated, multiple prime contractors with distinct and different goals, schedule pressures and funding constraints. However, SLS also faces unique challenges. The new program is a confluence of new hardware and heritage, with heritage hardware constituting seventy-five percent of the program. This unique approach to design makes logistics concerns such as commonality especially problematic. Additionally, a very low manifest rate of one flight every four years makes logistics comparatively expensive. That, along with the SLS architecture being developed using a block upgrade evolutionary approach, exacerbates long-range planning for supportability considerations. These common and unique logistics challenges must be clearly identified and tackled to allow SLS to have a successful program. This paper will address the common and unique challenges facing the SLS programs, along with the analysis and decisions the NASA Logistics engineers are making to mitigate the threats posed by each.

Measuring Changes in the Economics of Medical Practice.

PubMed

Fleming, Christopher; Rich, Eugene; DesRoches, Catherine; Reschovsky, James; Kogan, Rachel

2015-08-01

For the latter third of the twentieth century, researchers have estimated production and cost functions for physician practices. Today, those attempting to measure the inputs and outputs of physician practice must account for many recent changes in models of care delivery. In this paper, we review practice inputs and outputs as typically described in research on the economics of medical practice, and consider the implications of the changing organization of medical practice and nature of physician work. This evolving environment has created conceptual challenges in what are the appropriate measures of output from physician work, as well as what inputs should be measured. Likewise, the increasing complexity of physician practice organizations has introduced challenges to finding the appropriate data sources for measuring these constructs. Both these conceptual and data challenges pose measurement issues that must be overcome to study the economics of modern medical practice. Despite these challenges, there are several promising initiatives involving data sharing at the organizational level that could provide a starting point for developing the needed new data sources and metrics for physician inputs and outputs. However, additional efforts will be required to establish data collection approaches and measurements applicable to smaller and single specialty practices. Overcoming these measurement and data challenges will be key to supporting policy-relevant research on the changing economics of medical practice.

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.

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],…

Insights into the polerovirus-plant interactome revealed by co-immunoprecipitation and mass spectrometry

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,…

Many Faces Have I.

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…

Relative Clauses in Cantonese-English Bilingual Children: Typological Challenges and Processing Motivations

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,…

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…

Balancing Benefits and Risks of Immortal Data: Participants' Views of Open Consent in the Personal Genome Project.

PubMed

Zarate, Oscar A; Brody, Julia Green; Brown, Phil; Ramirez-Andreotta, Mónica D; Perovich, Laura; Matz, Jacob

2016-01-01

An individual's health, genetic, or environmental-exposure data, placed in an online repository, creates a valuable shared resource that can accelerate biomedical research and even open opportunities for crowd-sourcing discoveries by members of the public. But these data become "immortalized" in ways that may create lasting risk as well as benefit. Once shared on the Internet, the data are difficult or impossible to redact, and identities may be revealed by a process called data linkage, in which online data sets are matched to each other. Reidentification (re-ID), the process of associating an individual's name with data that were considered deidentified, poses risks such as insurance or employment discrimination, social stigma, and breach of the promises often made in informed-consent documents. At the same time, re-ID poses risks to researchers and indeed to the future of science, should re-ID end up undermining the trust and participation of potential research participants. The ethical challenges of online data sharing are heightened as so-called big data becomes an increasingly important research tool and driver of new research structures. Big data is shifting research to include large numbers of researchers and institutions as well as large numbers of participants providing diverse types of data, so the participants' consent relationship is no longer with a person or even a research institution. In addition, consent is further transformed because big data analysis often begins with descriptive inquiry and generation of a hypothesis, and the research questions cannot be clearly defined at the outset and may be unforeseeable over the long term. In this article, we consider how expanded data sharing poses new challenges, illustrated by genomics and the transition to new models of consent. We draw on the experiences of participants in an open data platform-the Personal Genome Project-to allow study participants to contribute their voices to inform ethical consent practices and protocol reviews for big-data research. © 2015 The Hastings Center.

Navigation Challenges of the Mars Phoenix Lander Mission

NASA Technical Reports Server (NTRS)

Portock, Brian M.; Kruizinga, Gerhard; Bonfiglio, Eugene; Raofi, Behzad; Ryne, Mark

2008-01-01

The Mars Phoenix Lander mission was launched on August 4th, 2007. To land safely at the desired landing location on the Mars surface, the spacecraft trajectory had to be controlled to a set of stringent atmospheric entry and landing conditions. The landing location needed to be controlled to an elliptical area with dimensions of 100km by 20km. The two corresponding critical components of the atmospheric entry conditions are the entry flight path angle (target: -13.0 deg +/-0.21 deg) and the entry time (within +/-30 seconds). The purpose of this paper is to describe the navigation strategies used to overcome the challenges posed during spacecraft operations, which included an attitude control thruster calibration campaign, a trajectory control strategy, and a trajectory reconstruction strategy. Overcoming the navigation challenges resulted in final Mars atmospheric entry conditions just 0.007 deg off in entry flight path angle and 14.9 sec early in entry time. These entry dispersions in addition to the entry, descent, and landing trajectory dispersion through the atmosphere, lead to a final landing location just 7 km away from the desired landing target.

[Protecting the labor rights of female nurses: an introduction to relevant laws and the challenges still ahead].

PubMed

Chiu, Hui-Ju; Cheng, Su-Fen; Lee, Ya-Ling

2015-02-01

The Gender Equality in Employment Act was enacted to protect gender equality in the workplace. Increasingly tight controls over operating costs by employers and the increasingly heavy workloads of nurses pose major challenges to the labor rights of female nurses. This article introduces the labor rights of female nurses as stated in relevant laws and regulations such as the Gender Equality in Employment Act, the Labor Standards Act, the Labor Insurance Act, Regulations on Leave-Taking for Workers, Regulations on Implementing Unpaid Parental Leave for Raising Children Pension Act, and the Employment Insurance Act. In addition, this paper introduces three judicial decisions that highlight domestic judicial practice with regard to labor rights in nursing. It is hoped that nurses may gain a better understanding of their rights and challenges from these judicial decisions. Finally, this article makes recommendations to help nurses overcome the difficulties in implementing labor rights. It is hoped that this article helps increase the general awareness among nurses of their labor rights and encourages nurses to pursue and secure their rightful labor rights from their employer.

Generation SMH (shaking my head): Work-Life Balance and Generational Realities

NASA Astrophysics Data System (ADS)

Jones, M. B.

2012-12-01

Many Federal Agencies have 'workforce development' programs that focus on preparing the next generation of scientists and engineers at the graduate and undergraduate level. Several of the science Agencies (e.g., NASA, NOAA, EPA, etc.), have programs that support students in many of the diverse disciplines that are unique to those Agency missions. While financial support certainly is critical to assist students in the STEM and other fields, professional development is just as important to equip students with a balanced arsenal of tactics to be successful professionals in the STEM workforce of today. Finding life balance as one moves through a STEM career path poses unique challenges that require a certain skill set that is not always intuitive. Some of those challenges include: selecting grad or post doc positions (negotiating to a family's advantage); balancing work and family commitments; and dealing with employer/advisor perceptions and expectations. For current and future generations in STEM, many of the above mentioned challenges require additional skill in negotiating interactions with individuals from other generations. Understanding perceptions and managing expectations are learnable skills that do not necessarily come with project funding.

The architecture challenge: Future artificial-intelligence systems will require sophisticated architectures, and knowledge of the brain might guide their construction.

PubMed

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.

Challenges and climate of business environment and resources to support pediatric device development.

PubMed

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…

Microbial Groundwater Sampling Protocol for Fecal-Rich Environments

PubMed Central

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

Climate Watch and Spoonbill Watch: Engaging Communities in Climate Science and Bird Conservation

NASA Astrophysics Data System (ADS)

Michel, N. L.; Baker, R.; Bergstrom, E.; Cox, D.; Cox, G.; Dale, K.; Jensen, C.; Langham, G.; LeBaron, G.; Loftus, W.; Rowden, J.; Slavin, Z.; Smithson-Stanley, L.; Wilsey, C.

2016-12-01

Climate change poses serious challenges for conservation scientists and policymakers. Yet with these challenges come equally great opportunities to engage communities of concerned citizens in climate science and conservation. National Audubon Society's 2014 Birds and Climate Change report found that 314 North American bird species could lose over half their breeding or wintering ranges by 2080 due to climate change. Consequently, in 2016 Audubon developed two new crowd-sourced science programs that mobilized existing birding communities (i.e., Audubon Society chapters) in partnership with scientists to evaluate climate change effects on birds, and take action to protect vulnerable populations. Climate Watch expands upon traditional monitoring programs by involving citizen scientists in hypothesis-driven science, testing predictions of climate-driven range expansion in bluebirds developed by National Audubon Society scientists. Spoonbill Watch is a partnership between an Audubon research scientist and the Pelican Island Audubon Society community, in which citizen scientists monitor a Roseate Spoonbill colony recently established in response to changing habitat and climatic conditions. Additionally, Spoonbill Watch participants and leaders have moved beyond monitoring to take action to protect the colony, by working with the Florida Fish and Wildlife Conservation Commission towards getting the site declared as a Critical Wildlife Area and by conducting local outreach and education efforts. We will present overviews, lessons learned, and conservation goals and opportunities achieved during the pilot year of Climate Watch and Spoonbill Watch. Scientific - community partnerships such as these are essential to confront the threats posed by climate change.

An Exploratory Framework for Handling the Complexity of Mathematical Problem Posing in Small Groups

ERIC Educational Resources Information Center

Kontorovich, Igor; Koichu, Boris; Leikin, Roza; Berman, Avi

2012-01-01

The paper introduces an exploratory framework for handling the complexity of students' mathematical problem posing in small groups. The framework integrates four facets known from past research: task organization, students' knowledge base, problem-posing heuristics and schemes, and group dynamics and interactions. In addition, it contains a new…

Posing Problems to Understand Children's Learning of Fractions

ERIC Educational Resources Information Center

Cheng, Lu Pien

2013-01-01

In this study, ways in which problem posing activities aid our understanding of children's learning of addition of unlike fractions and product of proper fractions was examined. In particular, how a simple problem posing activity helps teachers take a second, deeper look at children's understanding of fraction concepts will be discussed. The…

Exploration Design Challenge 2014

NASA Image and Video Library

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)

Exploring the Stability of Ligand Binding Modes to Proteins by Molecular Dynamics Simulations: A Cross-docking Study.

PubMed

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.

Testing Scientific Software: A Systematic Literature Review

PubMed Central

Kanewala, Upulee; Bieman, James M.

2014-01-01

Context Scientific software plays an important role in critical decision making, for example making weather predictions based on climate models, and computation of evidence for research publications. Recently, scientists have had to retract publications due to errors caused by software faults. Systematic testing can identify such faults in code. Objective This study aims to identify specific challenges, proposed solutions, and unsolved problems faced when testing scientific software. Method We conducted a systematic literature survey to identify and analyze relevant literature. We identified 62 studies that provided relevant information about testing scientific software. Results We found that challenges faced when testing scientific software fall into two main categories: (1) testing challenges that occur due to characteristics of scientific software such as oracle problems and (2) testing challenges that occur due to cultural differences between scientists and the software engineering community such as viewing the code and the model that it implements as inseparable entities. In addition, we identified methods to potentially overcome these challenges and their limitations. Finally we describe unsolved challenges and how software engineering researchers and practitioners can help to overcome them. Conclusions Scientific software presents special challenges for testing. Specifically, cultural differences between scientist developers and software engineers, along with the characteristics of the scientific software make testing more difficult. Existing techniques such as code clone detection can help to improve the testing process. Software engineers should consider special challenges posed by scientific software such as oracle problems when developing testing techniques. PMID:25125798

Hidden values in bauxite residue (red mud): recovery of metals.

PubMed

Liu, Yanju; Naidu, Ravi

2014-12-01

Bauxite residue (red mud) is a hazardous waste generated from alumina refining industries. Unless managed properly, red mud poses significant risks to the local environment due to its extreme alkalinity and its potential impacts on surface and ground water quality. The ever-increasing generation of red mud poses significant challenges to the aluminium industries from management perspectives given the low proportion that are currently being utilized beneficially. Red mud, in most cases, contains elevated concentrations of iron in addition to aluminium, titanium, sodium and valuable rare earth elements. Given the scarcity of iron supply globally, the iron content of red mud has attracted increasing research interest. This paper presents a critical overview of the current techniques employed for iron recovery from red mud. Information on the recovery of other valuable metals is also reviewed to provide an insight into the full potential usage of red mud as an economic resource rather than a waste. Traditional hydrometallurgy and pyrometallurgy are being investigated continuously. However, in this review several new techniques are introduced that consider the process of iron recovery from red mud. An integrated process which can achieve multiple additional values from red mud is much preferred over the single process methods. The information provided here should help to improve the future management and utilization of red mud. Copyright © 2014 Elsevier Ltd. All rights reserved.

A robust motion estimation system for minimal invasive laparoscopy

NASA Astrophysics Data System (ADS)

Marcinczak, Jan Marek; von Öhsen, Udo; Grigat, Rolf-Rainer

2012-02-01

Laparoscopy is a reliable imaging method to examine the liver. However, due to the limited field of view, a lot of experience is required from the surgeon to interpret the observed anatomy. Reconstruction of organ surfaces provide valuable additional information to the surgeon for a reliable diagnosis. Without an additional external tracking system the structure can be recovered from feature correspondences between different frames. In laparoscopic images blurred frames, specular reflections and inhomogeneous illumination make feature tracking a challenging task. We propose an ego-motion estimation system for minimal invasive laparoscopy that can cope with specular reflection, inhomogeneous illumination and blurred frames. To obtain robust feature correspondence, the approach combines SIFT and specular reflection segmentation with a multi-frame tracking scheme. The calibrated five-point algorithm is used with the MSAC robust estimator to compute the motion of the endoscope from multi-frame correspondence. The algorithm is evaluated using endoscopic videos of a phantom. The small incisions and the rigid endoscope limit the motion in minimal invasive laparoscopy. These limitations are considered in our evaluation and are used to analyze the accuracy of pose estimation that can be achieved by our approach. The endoscope is moved by a robotic system and the ground truth motion is recorded. The evaluation on typical endoscopic motion gives precise results and demonstrates the practicability of the proposed pose estimation system.

Finding the Words: Medical Students' Reflections on Communication Challenges in Clinic.

PubMed

Braverman, Genna; Bereknyei Merrell, Sylvia; Bruce, Janine S; Makoul, Gregory; Schillinger, Erika

2016-11-01

Interpersonal communication is essential to providing excellent patient care and requires ongoing development. Although aspects of medical student interpersonal communication may degrade throughout career progression, it is unknown what specific elements pose challenges. We aimed to characterize clerkship students' perspectives on communication challenges in the outpatient setting to help inform curricular development. Third-year medical students in a required family medicine clerkship were asked to describe a communication challenge they encountered. Open-ended written responses were collected through a mandatory post-clerkship survey. Responses were qualitatively coded using an a priori framework for teaching and assessing communication skills (The SEGUE Framework for Teaching and Assessing Communication Skills) with data-derived additions to the framework, followed by a team-based thematic analysis. We collected 799 reflections written by 518 students from 2007-2014. Three dominant themes emerged from the analysis: challenges with (1) effectively exchanging information with patients, (2) managing emotional aspects of the patient encounter, and (3) negotiating terms of the encounter. Communication curricula focus on content and process of the medical interview, but insufficient time and energy are devoted to psychosocial factors, including aspects of the encounter that are emotionally charged or conflicting. While gaps in students' communication skillsets may be anticipated or observed by educators, this study offers an analysis of students' own perceptions of the challenges they face.

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

PubMed Central

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

Design strategies of fluorescent probes for selective detection among biothiols.

PubMed

Niu, Li-Ya; Chen, Yu-Zhe; Zheng, Hai-Rong; Wu, Li-Zhu; Tung, Chen-Ho; Yang, Qing-Zheng

2015-10-07

Simple thiol derivatives, such as cysteine (Cys), homocysteine (Hcy), and glutathione (GSH), play key roles in biological processes, and the fluorescent probes to detect such thiols in vivo selectively with high sensitivity and fast response times are critical for understanding their numerous functions. However, the similar structures and reactivities of these thiols pose considerable challenges to the development of such probes. This review focuses on various strategies for the design of fluorescent probes for the selective detection of biothiols. We classify the fluorescent probes for discrimination among biothiols according to reaction types between the probes and thiols such as cyclization with aldehydes, conjugate addition-cyclization with acrylates, native chemical ligation, and aromatic substitution-rearrangement.

Automatic Parameterization Strategy for Cardiac Electrophysiology Simulations.

PubMed

Costa, Caroline Mendonca; Hoetzl, Elena; Rocha, Bernardo Martins; Prassl, Anton J; Plank, Gernot

2013-10-01

Driven by recent advances in medical imaging, image segmentation and numerical techniques, computer models of ventricular electrophysiology account for increasingly finer levels of anatomical and biophysical detail. However, considering the large number of model parameters involved parameterization poses a major challenge. A minimum requirement in combined experimental and modeling studies is to achieve good agreement in activation and repolarization sequences between model and experiment or patient data. In this study, we propose basic techniques which aid in determining bidomain parameters to match activation sequences. An iterative parameterization algorithm is implemented which determines appropriate bulk conductivities which yield prescribed velocities. In addition, a method is proposed for splitting the computed bulk conductivities into individual bidomain conductivities by prescribing anisotropy ratios.

Diagrammatic routes to nonlocal correlations beyond dynamical mean field theory

NASA Astrophysics Data System (ADS)

Rohringer, G.; Hafermann, H.; Toschi, A.; Katanin, A. A.; Antipov, A. E.; Katsnelson, M. I.; Lichtenstein, A. I.; Rubtsov, A. N.; Held, K.

2018-04-01

Strong electronic correlations pose one of the biggest challenges to solid state theory. Recently developed methods that address this problem by starting with the local, eminently important correlations of dynamical mean field theory (DMFT) are reviewed. In addition, nonlocal correlations on all length scales are generated through Feynman diagrams, with a local two-particle vertex instead of the bare Coulomb interaction as a building block. With these diagrammatic extensions of DMFT long-range charge, magnetic, and superconducting fluctuations as well as (quantum) criticality can be addressed in strongly correlated electron systems. An overview is provided of the successes and results achieved, mainly for model Hamiltonians, and an outline is given of future prospects for realistic material calculations.

A pharmacologic continuum in the treatment of rhinorrhea: the clinician as economist.

PubMed

Meltzer, E O; Tyrell, R J; Rich, D; Wood, C C

1995-05-01

The economics of medications are now of great concern to health-care providers. Pharmacoeconomic issues are by no means simple, and yet, ironically, they assume greater importance in prescribing for modest disorders like rhinorrhea than for life-threatening conditions. The therapeutic continuum of quality and cost becomes foreshortened, and safety is an additional concern. Choosing the appropriate medication for rhinorrhea, then, can pose a challenge to the clinician, just as choosing a vital medication. This paper reviews the usage, quality, and cost of major therapies for the rhinorrhea that occurs secondary to various conditions, including nasal steroids, antihistamines and anticholinergics, and discusses the role of the clinician in factoring costs into therapy.

Conceptualizing threats to tobacco control from international economic agreements: the Brazilian experience.

PubMed

Drope, Jeffrey; McGrady, Benn; Bialous, Stella Aguinaga; Lencucha, Raphael; Silva, Vera Luiza da Costa E

2017-10-19

Using the results of dozens of interviews with key actors involved in tobacco control policymaking, we examine these actors' perceptions of threats to tobacco control policy efforts from international economic policies on trade and investment. We also evaluate, from a legal perspective, the genuine threats that exist or potential challenges that economic policies may pose to the Brazilian government's public health efforts. We find that most actors did not perceive these economic policies as a major threat to tobacco control. Objectively, we found that some threats do exist. For example, Brazil's attempt to ban most tobacco additives and flavorings continues to met resistance at the World Trade Organization.

Incorporating Target Priorities in the Sensor Tasking Reward Function

NASA Astrophysics Data System (ADS)

Gehly, S.; Bennett, J.

2016-09-01

Orbital debris tracking poses many challenges, most fundamentally the need to track a large number of objects from a limited number of sensors. The use of information theoretic sensor allocation provides a means to efficiently collect data on the multitarget system. An additional need of the community is the ability to specify target priorities, driven both by user needs and environmental factors such as collision warnings. This research develops a method to incorporate target priorities in the sensor tasking reward function, allowing for several applications in different tasking modes such as catalog maintenance, calibration, and collision monitoring. A set of numerical studies is included to demonstrate the functionality of the method.

Individualized radiotherapy by combining high-end irradiation and magnetic resonance imaging.

PubMed

Combs, Stephanie E; Nüsslin, Fridtjof; Wilkens, Jan J

2016-04-01

Image-guided radiotherapy (IGRT) has been integrated into daily clinical routine and can today be considered the standard especially with high-dose radiotherapy. Currently imaging is based on MV- or kV-CT, which has clear limitations especially in soft-tissue contrast. Thus, combination of magnetic resonance (MR) imaging and high-end radiotherapy opens a new horizon. The intricate technical properties of MR imagers pose a challenge to technology when combined with radiation technology. Several solutions that are almost ready for routine clinical application have been developed. The clinical questions include dose-escalation strategies, monitoring of changes during treatment as well as imaging without additional radiation exposure during treatment.

Color engineering in the age of digital convergence

NASA Astrophysics Data System (ADS)

MacDonald, Lindsay W.

1998-09-01

Digital color imaging has developed over the past twenty years from specialized scientific applications into the mainstream of computing. In addition to the phenomenal growth of computer processing power and storage capacity, great advances have been made in the capabilities and cost-effectiveness of color imaging peripherals. The majority of imaging applications, including the graphic arts, video and film have made the transition from analogue to digital production methods. Digital convergence of computing, communications and television now heralds new possibilities for multimedia publishing and mobile lifestyles. Color engineering, the application of color science to the design of imaging products, is an emerging discipline that poses exciting challenges to the international color imaging community for training, research and standards.

A qualitative exploration of district nurses' care of patients with advanced cancer: the challenges of supporting families within the home.

PubMed

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.

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.

PubMed

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.

PubMed

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.

Techniques for High Contrast Imaging in Multi-Star Systems II: Multi-Star Wavefront Control

NASA Technical Reports Server (NTRS)

Sirbu, D.; Thomas, S.; Belikov, R.

2017-01-01

Direct imaging of exoplanets represents a challenge for astronomical instrumentation due to the high-contrast ratio and small angular separation between the host star and the faint planet. Multi-star systems pose additional challenges for coronagraphic instruments because of the diffraction and aberration leakage introduced by the additional stars, and as a result are not planned to be on direct imaging target lists. Multi-star wavefront control (MSWC) is a technique that uses a coronagraphic instrument's deformable mirror (DM) to create high-contrast regions in the focal plane in the presence of multiple stars. Our previous paper introduced the Super-Nyquist Wavefront Control (SNWC) technique that uses a diffraction grating to enable the DM to generate high-contrast regions beyond the nominal controllable region. These two techniques can be combined to generate high-contrast regions for multi-star systems at any angular separations. As a case study, a high-contrast wavefront control (WC) simulation that applies these techniques shows that the habitable region of the Alpha Centauri system can be imaged reaching 8 times 10(exp -9) mean contrast in 10 percent broadband light in one-sided dark holes from 1.6-5.5 lambda (wavelength) divided by D (distance).

Near-infrared laser-induced fluorescence detection in capillary electrophoresis.

PubMed

McWhorter, S; Soper, S A

2000-04-01

As capillary electrophoresis continues to focus on miniaturization, either through reducing column dimensions or situating entire electrophoresis systems on planar chips, advances in detection become necessary to meet the challenges posed by these electrophoresis platforms. The challenges result from the fact that miniaturization requires smaller load volumes, demanding highly sensitive detection. In addition, many times multiple targets must be analyzed simultaneously (multiplexed applications), further complicating detection. Near-infrared (NIR) fluorescence offers an attractive alternative to visible fluorescence for critical applications in capillary electrophoresis due to the impressive limits of detection that can be generated, in part resulting from the low background levels that are observed in the NIR. Advances in instrumentation and fluorogenic labels appropriate for NIR monitoring have led to a growing number of examples of the use of NIR fluorescence in capillary electrophoresis. In this review, we will cover instrumental components used to construct ultrasensitive NIR fluorescence detectors, including light sources and photon transducers. In addition, we will discuss various types of labeling dyes appropriate for NIR fluorescence and finally, we will present several applications that have used NIR fluorescence in capillary electrophoresis, especially for DNA sequencing and fragment analysis.

Co-occurring disorder clusters in adults with mild and moderate intellectual disability in residential treatment settings.

PubMed

Turygin, Nicole C; Matson, Johnny L; Adams, Hilary L; Williams, Lindsey W

2014-11-01

In the typically developing population, co-occurring psychopathology is not uncommon and is a topic of importance among psychologists. It is only recently that the psychopathology in individuals with intellectual disability (ID) has become an area of significant clinical and research interest. Individuals with ID are believed to be at a greater risk for co-occurring disorders compared to the typical population. By definition, ID involves deficits in adaptive behavior, which necessitates the use of community services, or specialized services at residential facilities to manage severe challenging behaviors or psychiatric disorders. The presence of co-occurring disorders in addition to ID can complicate treatment, limit available services, and restrict opportunities for individuals with ID. The present study examines the prevalence of co-occurring psychiatric disorders and ID in a sample of 78 individuals with mild to moderate ID living in a long-term residential treatment facility diagnosed with psychiatric disorders. Certain psychiatric disorders were more likely to co-occur together in this population. Identifying and treating individuals with multiple psychopathologies in addition to ID poses challenges unique to the population. Copyright © 2014 Elsevier Ltd. All rights reserved.

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

NASA Image and Video Library

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

DTIC Science & Technology

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

Green Flight Challenge

NASA Image and Video Library

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)

Green Flight Challenge

NASA Image and Video Library

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)

Green Flight Challenge

NASA Image and Video Library

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)

Green Flight Challenge

NASA Image and Video Library

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)

Green Flight Challenge

NASA Image and Video Library

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…

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…

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…

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…

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…

Review of Federal Motor Vehicle Safety Standards (FMVSS) for Automated Vehicles : Identifying Potential Barriers and Challenges for the Certification of Automated Vehicles Using Existing FMVSS

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...

Planning the future's forests with assisted migration

Treesearch

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...

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…

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…

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…

Towards a Clearer Understanding of Student Disadvantage in Higher Education: Problematising Deficit Thinking

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…

From a Semiotic Perspective: Inference Formation and the Critical Comprehension of Television Advertising.

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…

US EPA - A*Star Partnership - Accelerating the Acceptance of Next-Generation Sciences and Their Application to Regulatory Risk Assessment (A*Star Symposium, Singapore)

EPA Science Inventory

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)

UCSC genome browser: deep support for molecular biomedical research.

PubMed

Mangan, Mary E; Williams, Jennifer M; Lathe, Scott M; Karolchik, Donna; Lathe, Warren C

2008-01-01

The volume and complexity of genomic sequence data, and the additional experimental data required for annotation of the genomic context, pose a major challenge for display and access for biomedical researchers. Genome browsers organize this data and make it available in various ways to extract useful information to advance research projects. The UCSC Genome Browser is one of these resources. The official sequence data for a given species forms the framework to display many other types of data such as expression, variation, cross-species comparisons, and more. Visual representations of the data are available for exploration. Data can be queried with sequences. Complex database queries are also easily achieved with the Table Browser interface. Associated tools permit additional query types or access to additional data sources such as images of in situ localizations. Support for solving researcher's issues is provided with active discussion mailing lists and by providing updated training materials. The UCSC Genome Browser provides a source of deep support for a wide range of biomedical molecular research (http://genome.ucsc.edu).

Postural Communication of Emotion: Perception of Distinct Poses of Five Discrete Emotions.

PubMed

Lopez, Lukas D; Reschke, Peter J; Knothe, Jennifer M; Walle, Eric A

2017-01-01

Emotion can be communicated through multiple distinct modalities. However, an often-ignored channel of communication is posture. Recent research indicates that bodily posture plays an important role in the perception of emotion. However, research examining postural communication of emotion is limited by the variety of validated emotion poses and unknown cohesion of categorical and dimensional ratings. The present study addressed these limitations. Specifically, we examined individuals' (1) categorization of emotion postures depicting 5 discrete emotions (joy, sadness, fear, anger, and disgust), (2) categorization of different poses depicting the same discrete emotion, and (3) ratings of valence and arousal for each emotion pose. Findings revealed that participants successfully categorized each posture as the target emotion, including disgust. Moreover, participants accurately identified multiple distinct poses within each emotion category. In addition to the categorical responses, dimensional ratings of valence and arousal revealed interesting overlap and distinctions between and within emotion categories. These findings provide the first evidence of an identifiable posture for disgust and instantiate the principle of equifinality of emotional communication through the inclusion of distinct poses within emotion categories. Additionally, the dimensional ratings corroborated the categorical data and provide further granularity for future researchers to consider in examining how distinct emotion poses are perceived.

3D face recognition under expressions, occlusions, and pose variations.

PubMed

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.

The Additional Error of Inertial Sensors Induced by Hypersonic Flight Conditions

PubMed Central

Karachun, Volodimir; Mel’nick, Viktorij; Korobiichuk, Igor; Nowicki, Michał; Szewczyk, Roman; Kobzar, Svitlana

2016-01-01

The emergence of hypersonic technology pose a new challenge for inertial navigation sensors, widely used in aerospace industry. The main problems are: extremely high temperatures, vibration of the fuselage, penetrating acoustic radiation and shock N-waves. The nature of the additional errors of the gyroscopic inertial sensor with hydrostatic suspension components under operating conditions generated by forced precession of the movable part of the suspension due to diffraction phenomena in acoustic fields is explained. The cause of the disturbing moments in the form of the Coriolis inertia forces during the transition of the suspension surface into the category of impedance is revealed. The boundaries of occurrence of the features on the resonance wave match are described. The values of the “false” angular velocity as a result of the elastic-stress state of suspension in the acoustic fields are determined. PMID:26927122

Communicating about smoke from wildland fire: challenges and opportunities for managers.

PubMed

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.

A qualitative description of service providers' experiences of ethical issues in HIV care.

PubMed

Sabone, Motshedisi B; Mogobe, Keitshokile Dintle; Matshediso, Ellah; Shaibu, Sheila; Ntsayagae, Esther I; Corless, Inge B; Cuca, Yvette P; Holzemer, William L; Dawson-Rose, Carol; Baez, Solymar S Soliz; Rivero-Mendz, Marta; Webel, Allison R; Eller, Lucille Sanzero; Reid, Paula; Johnson, Mallory O; Kemppainen, Jeanne; Reyes, Darcel; Nokes, Kathleen; Wantland, Dean; Nicholas, Patrice K; Lingren, Teri; Portillo, Carmen J; Sefcik, Elizabeth; Long-Middleton, Ellen

2018-01-01

Managing HIV treatment is a complex multi-dimensional task because of a combination of factors such as stigma and discrimination of some populations who frequently get infected with HIV. In addition, patient-provider encounters have become increasingly multicultural, making effective communication and provision of ethically sound care a challenge. This article explores ethical issues that health service providers in the United States and Botswana encountered in their interaction with patients in HIV care. A descriptive qualitative design was used to collect data from health service providers and patients using focused group discussions. This article is based on responses from health service providers only. Participants and context: This article is based on 11 focused group discussions with a total sample of 71 service providers in seven US sites and one Botswana site. Ethical considerations: Ethical review boards at all the study sites reviewed the study protocol and approved it. Ethical review boards of the study's coordinating centers, Rutgers University and the University of California at San Francisco, also approved it. The study participants provided a written informed consent to participate. HIV service providers encountered ethical challenges in all the four Beauchamp and Childress' biomedical ethics of respect for patients' autonomy, beneficence, justice, and nonmaleficence. The finding that HIV service providers encounter ethical challenges in their interaction with patients is supported by prior studies. The ethical challenges are particularly prominent in multicultural care and resource-constrained care environments. Provision of HIV care is fraught with ethical challenges that tend to pose different issues depending on a given care environment. It is important that strong partnerships are developed among key stakeholders in HIV care. In addition, health service providers need to be provided with resources so they can provide quality and ethically sound care.

Optical flow and driver's kinematics analysis for state of alert sensing.

PubMed

Jiménez-Pinto, Javier; Torres-Torriti, Miguel

2013-03-28

Road accident statistics from different countries show that a significant number of accidents occur due to driver's fatigue and lack of awareness to traffic conditions. In particular, about 60% of the accidents in which long haul truck and bus drivers are involved are attributed to drowsiness and fatigue. It is thus fundamental to improve non-invasive systems for sensing a driver's state of alert. One of the main challenges to correctly resolve the state of alert is measuring the percentage of eyelid closure over time (PERCLOS), despite the driver's head and body movements. In this paper, we propose a technique that involves optical flow and driver's kinematics analysis to improve the robustness of the driver's alert state measurement under pose changes using a single camera with near-infrared illumination. The proposed approach infers and keeps track of the driver's pose in 3D space in order to ensure that eyes can be located correctly, even after periods of partial occlusion, for example, when the driver stares away from the camera. Our experiments show the effectiveness of the approach with a correct eyes detection rate of 99.41%, on average. The results obtained with the proposed approach in an experiment involving fifteen persons under different levels of sleep deprivation also confirm the discriminability of the fatigue levels. In addition to the measurement of fatigue and drowsiness, the pose tracking capability of the proposed approach has potential applications in distraction assessment and alerting of machine operators.

Human action recognition based on kinematic similarity in real time

PubMed Central

Chen, Longting; Luo, Ailing; Zhang, Sicong

2017-01-01

Human action recognition using 3D pose data has gained a growing interest in the field of computer robotic interfaces and pattern recognition since the availability of hardware to capture human pose. In this paper, we propose a fast, simple, and powerful method of human action recognition based on human kinematic similarity. The key to this method is that the action descriptor consists of joints position, angular velocity and angular acceleration, which can meet the different individual sizes and eliminate the complex normalization. The angular parameters of joints within a short sliding time window (approximately 5 frames) around the current frame are used to express each pose frame of human action sequence. Moreover, three modified KNN (k-nearest-neighbors algorithm) classifiers are employed in our method: one for achieving the confidence of every frame in the training step, one for estimating the frame label of each descriptor, and one for classifying actions. Additional estimating of the frame’s time label makes it possible to address single input frames. This approach can be used on difficult, unsegmented sequences. The proposed method is efficient and can be run in real time. The research shows that many public datasets are irregularly segmented, and a simple method is provided to regularize the datasets. The approach is tested on some challenging datasets such as MSR-Action3D, MSRDailyActivity3D, and UTD-MHAD. The results indicate our method achieves a higher accuracy. PMID:29073131

Optical Flow and Driver's Kinematics Analysis for State of Alert Sensing

PubMed Central

Jiménez-Pinto, Javier; Torres-Torriti, Miguel

2013-01-01

Road accident statistics from different countries show that a significant number of accidents occur due to driver's fatigue and lack of awareness to traffic conditions. In particular, about 60% of the accidents in which long haul truck and bus drivers are involved are attributed to drowsiness and fatigue. It is thus fundamental to improve non-invasive systems for sensing a driver's state of alert. One of the main challenges to correctly resolve the state of alert is measuring the percentage of eyelid closure over time (PERCLOS), despite the driver's head and body movements. In this paper, we propose a technique that involves optical flow and driver's kinematics analysis to improve the robustness of the driver's alert state measurement under pose changes using a single camera with near-infrared illumination. The proposed approach infers and keeps track of the driver's pose in 3D space in order to ensure that eyes can be located correctly, even after periods of partial occlusion, for example, when the driver stares away from the camera. Our experiments show the effectiveness of the approach with a correct eyes detection rate of 99.41%, on average. The results obtained with the proposed approach in an experiment involving fifteen persons under different levels of sleep deprivation also confirm the discriminability of the fatigue levels. In addition to the measurement of fatigue and drowsiness, the pose tracking capability of the proposed approach has potential applications in distraction assessment and alerting of machine operators. PMID:23539029

Experimental Design for Evaluating Selected Nondestructive Measurement Technologies - Advanced Reactor Technology Milestone: M3AT-16PN2301043

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.

PubMed

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.

Structure-From-Motion in 3D Space Using 2D Lidars

PubMed Central

Choi, Dong-Geol; Bok, Yunsu; Kim, Jun-Sik; Shim, Inwook; Kweon, In So

2017-01-01

This paper presents a novel structure-from-motion methodology using 2D lidars (Light Detection And Ranging). In 3D space, 2D lidars do not provide sufficient information for pose estimation. For this reason, additional sensors have been used along with the lidar measurement. In this paper, we use a sensor system that consists of only 2D lidars, without any additional sensors. We propose a new method of estimating both the 6D pose of the system and the surrounding 3D structures. We compute the pose of the system using line segments of scan data and their corresponding planes. After discarding the outliers, both the pose and the 3D structures are refined via nonlinear optimization. Experiments with both synthetic and real data show the accuracy and robustness of the proposed method. PMID:28165372

Injuries in the North – analysis of 20 years of surveillance data collected by the Canadian Hospitals Injury Reporting and Prevention Program

PubMed Central

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

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

NASA Image and Video Library

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

NASA Image and Video Library

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

DTIC Science & Technology

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

Green Flight Challenge

NASA Image and Video Library

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)

Green Flight Challenge

NASA Image and Video Library

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)

Challenges of Remote Sensing and Spatial Information Education and Technology Transfer in a Fast Developing Industry

NASA Astrophysics Data System (ADS)

Tsai, F.; Chen, L.-C.

2014-04-01

During the past decade, Taiwan has experienced an unusual and fast growing in the industry of mapping, remote sensing, spatial information and related markets. A successful space program and dozens of advanced airborne and ground-based remote sensing instruments as well as mobile mapping systems have been implemented and put into operation to support the vast demands of geospatial data acquisition. Moreover, in addition to the government agencies and research institutes, there are also tens of companies in the private sector providing geo-spatial data and services. However, the fast developing industry is also posing a great challenge to the education sector in Taiwan, especially the higher education for geo-spatial information. Facing this fast developing industry, the demands of skilled professionals and new technologies in order to address diversified needs are indubitably high. Consequently, while delighting in the expanding and prospering benefitted from the fast growing industry, how to fulfill these demands has become a challenge for the remote sensing and spatial information disciplines in the higher education institutes in Taiwan. This paper provides a brief insight into the status of the remote sensing and spatial information industry in Taiwan as well as the challenges of the education and technology transfer to support the increasing demands and to ensure the continuous development of the industry. In addition to the report of the current status of the remote sensing and spatial information related courses and programs in the colleges and universities, current and potential threatening issues and possible resolutions are also discussed in different points of view.

Challenges in Infective Endocarditis.

PubMed

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.

The Twin Epidemics of Tuberculosis and HIV.

PubMed

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.

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,…

Assessing Graduate Sustainability Capability Post-Degree Completion: Why Is It Important and What Are the Challenges?

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…

A Systematic Approach to Faculty Development toward Improved Capability in Tertiary Teaching in a Blended Learning Environment

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…

Assisted migration: What it means to nursery managers and tree planters

Treesearch

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...

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…

Employer Understanding of Work-Integrated Learning and the Challenges of Engaging in Work Placement Opportunities

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…

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.

PubMed

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…

Assessing the Potential for Openness: A Framework for Examining Course-Level OER Implementation in Higher Education

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…

"What Do You Do All Day?!": Navigating the Challenges of School Leadership as an Early Career Principal

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

Treesearch

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...

Responding to the Challenge: Giving Pre-Service Classroom Teachers a Musical Language and Understanding

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…

One Goal, Two Institutions: How a Community College and 4-Year University Partner to Bridge Student College Readiness Gaps

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…

Predicting Placement Breakdown: Individual and Environmental Factors Associated with the Success or Failure of Community Residential Placements for Adults with Intellectual Disabilities

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…

Engaging Adolescents with LD in Higher Order Thinking about History Concepts Using Integrated Content Enhancement Routines

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…

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…

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

Treesearch

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...

Toxcast and the Use of Human Relevant In Vitro Exposures: Incorporating High-Throughput Exposure and Toxicity Testing Data for 21st Century Risk Assessments (British Toxicological Society Annual Congress)

EPA Science Inventory

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…

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…

The Relationship between Education and Child Work. Innocenti Occasional Papers Child Rights Series, Number 9.

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…

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.

A Bayesian Framework for Human Body Pose Tracking from Depth Image Sequences

PubMed Central

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

International Standards for Neurological Classification of Spinal Cord Injury: cases with classification challenges.

PubMed

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.

Nutrition status of children in Latin America

PubMed Central

Garmendia, M. L.; Jones‐Smith, J.; Lutter, C. K.; Miranda, J. J.; Pedraza, L. S.; Popkin, B. M.; Ramirez‐Zea, M.; Salvo, D.; Stein, A. D.

2017-01-01

Summary The prevalence of overweight and obesity is rapidly increasing among Latin American children, posing challenges for current healthcare systems and increasing the risk for a wide range of diseases. To understand the factors contributing to childhood obesity in Latin America, this paper reviews the current nutrition status and physical activity situation, the disparities between and within countries and the potential challenges for ensuring adequate nutrition and physical activity. Across the region, children face a dual burden of undernutrition and excess weight. While efforts to address undernutrition have made marked improvements, childhood obesity is on the rise as a result of diets that favour energy‐dense, nutrient‐poor foods and the adoption of a sedentary lifestyle. Over the last decade, changes in socioeconomic conditions, urbanization, retail foods and public transportation have all contributed to childhood obesity in the region. Additional research and research capacity are needed to address this growing epidemic, particularly with respect to designing, implementing and evaluating the impact of evidence‐based obesity prevention interventions. PMID:28741907

Craniopharyngioma: a roadmap for scientific translation.

PubMed

Gupta, Saksham; Bi, Wenya Linda; Giantini Larsen, Alexandra; Al-Abdulmohsen, Sally; Abedalthagafi, Malak; Dunn, Ian F

2018-06-01

OBJECTIVE Craniopharyngiomas are among the most challenging of intracranial tumors to manage because of their pattern of growth, associated morbidities, and high recurrence rate. Complete resection on initial encounter can be curative, but it may be impeded by the risks posed by the involved neurovascular structures. Recurrent craniopharyngiomas, in turn, are frequently refractory to additional surgery and adjuvant radiation or chemotherapy. METHODS The authors conducted a review of primary literature. RESULTS Recent advances in the understanding of craniopharyngioma biology have illuminated potential oncogenic targets for pharmacotherapy. Specifically, distinct molecular profiles define two histological subtypes of craniopharyngioma: adamantinomatous and papillary. The discovery of overactive B-Raf signaling in the adult papillary subtype has led to reports of targeted inhibitors, with a growing acceptance for refractory cases. An expanding knowledge of the biological underpinnings of craniopharyngioma will continue to drive development of targeted therapies and immunotherapies that are personalized to the molecular signature of each individual tumor. CONCLUSIONS The rapid translation of genomic findings to medical therapies for recurrent craniopharyngiomas serves as a roadmap for other challenging neurooncological diseases.

Open-access databases as unprecedented resources and drivers of cultural change in fisheries science

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

McManamay, Ryan A; Utz, Ryan

2014-01-01

Open-access databases with utility in fisheries science have grown exponentially in quantity and scope over the past decade, with profound impacts to our discipline. The management, distillation, and sharing of an exponentially growing stream of open-access data represents several fundamental challenges in fisheries science. Many of the currently available open-access resources may not be universally known among fisheries scientists. We therefore introduce many national- and global-scale open-access databases with applications in fisheries science and provide an example of how they can be harnessed to perform valuable analyses without additional field efforts. We also discuss how the development, maintenance, and utilizationmore » of open-access data are likely to pose technical, financial, and educational challenges to fisheries scientists. Such cultural implications that will coincide with the rapidly increasing availability of free data should compel the American Fisheries Society to actively address these problems now to help ease the forthcoming cultural transition.« less

Pesticide Vendors in the Informal Sector: Trading Health for Income.

PubMed

Rother, Hanna-Andrea

2016-08-01

South African low-income communities face many challenges (e.g., insufficient housing, poor service delivery, and abject poverty); additionally, a silent challenge of pest infestation plagues these areas resulting in disease risks, nuisances, and stigma. Consequently, an enterprising urban informal sector business has emerged providing residents with highly toxic, effective, cheap, and illegal "street pesticides." These pesticides pose acute and chronic health risks for vendors and residents. The economic opportunity provided by the high demand for effective and cheap pest control results in the high risk of health effects being traded for income. Current measures to control and "regulate" the massive street pesticide sales result in toxic stockpiles and government's "turning a blind eye." Solutions will only be achieved through open dialog identifying and developing non-toxic pest control strategies while ensuring vendors' income; and relevant stakeholder recognition that pest infestation is a social and environmental health determinant needing acknowledgement in different government policies. © The Author(s) 2016.

Diffuse-Interface Modelling of Flow in Porous Media

NASA Astrophysics Data System (ADS)

Addy, Doug; Pradas, Marc; Schmuck, Marcus; Kalliadasis, Serafim

2016-11-01

Multiphase flows are ubiquitous in a wide spectrum of scientific and engineering applications, and their computational modelling often poses many challenges associated with the presence of free boundaries and interfaces. Interfacial flows in porous media encounter additional challenges and complexities due to their inherently multiscale behaviour. Here we investigate the dynamics of interfaces in porous media using an effective convective Cahn-Hilliard (CH) equation recently developed in from a Stokes-CH equation for microscopic heterogeneous domains by means of a homogenization methodology, where the microscopic details are taken into account as effective tensor coefficients which are given by a Poisson equation. The equations are decoupled under appropriate assumptions and solved in series using a classic finite-element formulation with the open-source software FEniCS. We investigate the effects of different microscopic geometries, including periodic and non-periodic, at the bulk fluid flow, and find that our model is able to describe the effective macroscopic behaviour without the need to resolve the microscopic details.

Regulatory Considerations in the Design and Manufacturing of Implantable 3D‐Printed Medical Devices

PubMed Central

Morrison, Robert J.; Kashlan, Khaled N.; Flanangan, Colleen L.; Wright, Jeanne K.; Green, Glenn E.; Hollister, Scott J.

2015-01-01

Abstract Three‐dimensional (3D) printing, or additive manufacturing, technology has rapidly penetrated the medical device industry over the past several years, and innovative groups have harnessed it to create devices with unique composition, structure, and customizability. These distinctive capabilities afforded by 3D printing have introduced new regulatory challenges. The customizability of 3D‐printed devices introduces new complexities when drafting a design control model for FDA consideration of market approval. The customizability and unique build processes of 3D‐printed medical devices pose unique challenges in meeting regulatory standards related to the manufacturing quality assurance. Consistent material powder properties and optimal printing parameters such as build orientation and laser power must be addressed and communicated to the FDA to ensure a quality build. Postprinting considerations unique to 3D‐printed devices, such as cleaning, finishing and sterilization are also discussed. In this manuscript we illustrate how such regulatory hurdles can be navigated by discussing our experience with our group's 3D‐printed bioresorbable implantable device. PMID:26243449

Hitting the ground running

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

KEENEN,MARTHA JANE; NUSBAUM,ANNA W.

2000-05-18

Very few of us get to start clean: getting a new organization, new space, and hiring new people for a new information management program. In over 20 years in some aspect of this profession, the author has never faced that particular challenge. By far the majority of information management opportunities involve taking over from someone else. Sometimes, a predecessor has gone on to better things on his/her initiative; that is not always the case. Sometimes the group is one you were a part of yesterday. If the function functions, time moves on and changes may be needed to accommodate newmore » technology, additional and/or changed tasks, and alterations in corporate missions. If the function does not, it is a good bet that you were hired or promoted as an agent of change. Each of these situations poses challenges. This presentation is about that first few months and first year in a new assignment. In other words, you have the job, now what?« less

Current status of deepwater oil spill modelling in the Faroe-Shetland Channel, Northeast Atlantic, and future challenges.

PubMed

Gallego, Alejandro; O'Hara Murray, Rory; Berx, Barbara; Turrell, William R; Beegle-Krause, C J; Inall, Mark; Sherwin, Toby; Siddorn, John; Wakelin, Sarah; Vlasenko, Vasyl; Hole, Lars R; Dagestad, Knut Frode; Rees, John; Short, Lucy; Rønningen, Petter; Main, Charlotte E; Legrand, Sebastien; Gutierrez, Tony; Witte, Ursula; Mulanaphy, Nicole

2018-02-01

As oil reserves in established basins become depleted, exploration and production moves towards relatively unexploited areas, such as deep waters off the continental shelf. The Faroe-Shetland Channel (FSC, NE Atlantic) and adjacent areas have been subject to increased focus by the oil industry. In addition to extreme depths, metocean conditions in this region characterise an environment with high waves and strong winds, strong currents, complex circulation patterns, sharp density gradients, and large small- and mesoscale variability. These conditions pose operational challenges to oil spill response and question the suitability of current oil spill modelling frameworks (oil spill models and their forcing data) to adequately simulate the behaviour of a potential oil spill in the area. This article reviews the state of knowledge relevant to deepwater oil spill modelling for the FSC area and identifies knowledge gaps and research priorities. Our analysis should be relevant to other areas of complex oceanography. Crown Copyright © 2017. Published by Elsevier Ltd. All rights reserved.

Toward evidence-based conflicts of interest training for physician-investigators.

PubMed

Greenwood, Kate; Coleman, Carl H; Boozang, Kathleen M

2012-01-01

The increased focus in recent years on the risks posed by conflicts of interest arising from financial relationships between physician-investigators and the pharmaceutical and medical device industries has led to a variety of measures that can broadly be described as "regulatory" interventions, including new federal and state laws, criminal prosecutions and private lawsuits, requirements attached to government funding, and institutional policies. Studies suggest, however, that physician-investigators have not internalized the message that financial conflicts of interest have the potential to influence their decision making. Simply informing physician-investigators of the content of relevant rules and the consequences of noncompliance - as appears to be the practice in many existing compliance training activities - is unlikely to lead to lasting changes in norms or behavior. Instead, we theorize that, for trainings to be maximally effective, they must appeal to the complex intrinsic and extrinsic motivations that contribute to individuals' willingness to comply with regulatory mandates. In addition, physician-investigators' beliefs that the risks posed by conflicts of interest do not apply to them need to be challenged. Rigorous evaluation of the newly-designed training programs will help determine whether these theories are borne out in fact. © 2012 American Society of Law, Medicine & Ethics, Inc.

Herbicides as Weed Control Agents: State of the Art: II. Recent Achievements[C

PubMed Central

Kraehmer, Hansjoerg; van Almsick, Andreas; Beffa, Roland; Dietrich, Hansjoerg; Eckes, Peter; Hacker, Erwin; Hain, Ruediger; Strek, Harry John; Stuebler, Hermann; Willms, Lothar

2014-01-01

In response to changing market dynamics, the discovery of new herbicides has declined significantly over the past few decades and has only seen a modest upsurge in recent years. Nevertheless, the few introductions have proven to be interesting and have brought useful innovation to the market. In addition, herbicide-tolerant or herbicide-resistant crop technologies have allowed the use of existing nonselective herbicides to be extended into crops. An increasing and now major challenge is being posed by the inexorable increase in biotypes of weeds that are resistant to herbicides. This problem is now at a level that threatens future agricultural productivity and needs to be better understood. If herbicides are to remain sustainable, then it is a must that we adopt diversity in crop rotation and herbicide use as well as increase the use of nonchemical measures to control weeds. Nevertheless, despite the difficulties posed by resistant weeds and increased regulatory hurdles, new screening tools promise to provide an upsurge of potential herbicide leads. Our industry urgently needs to supply agriculture with new, effective resistance-breaking herbicides along with strategies to sustain their utility. PMID:25104721

Herbicides as weed control agents: state of the art: II. Recent achievements.

PubMed

Kraehmer, Hansjoerg; van Almsick, Andreas; Beffa, Roland; Dietrich, Hansjoerg; Eckes, Peter; Hacker, Erwin; Hain, Ruediger; Strek, Harry John; Stuebler, Hermann; Willms, Lothar

2014-11-01

In response to changing market dynamics, the discovery of new herbicides has declined significantly over the past few decades and has only seen a modest upsurge in recent years. Nevertheless, the few introductions have proven to be interesting and have brought useful innovation to the market. In addition, herbicide-tolerant or herbicide-resistant crop technologies have allowed the use of existing nonselective herbicides to be extended into crops. An increasing and now major challenge is being posed by the inexorable increase in biotypes of weeds that are resistant to herbicides. This problem is now at a level that threatens future agricultural productivity and needs to be better understood. If herbicides are to remain sustainable, then it is a must that we adopt diversity in crop rotation and herbicide use as well as increase the use of nonchemical measures to control weeds. Nevertheless, despite the difficulties posed by resistant weeds and increased regulatory hurdles, new screening tools promise to provide an upsurge of potential herbicide leads. Our industry urgently needs to supply agriculture with new, effective resistance-breaking herbicides along with strategies to sustain their utility. © 2014 American Society of Plant Biologists. All Rights Reserved.

Proteomics research in India: an update.

PubMed

Reddy, Panga Jaipal; Atak, Apurva; Ghantasala, Saicharan; Kumar, Saurabh; Gupta, Shabarni; Prasad, T S Keshava; Zingde, Surekha M; Srivastava, Sanjeeva

2015-09-08

After a successful completion of the Human Genome Project, deciphering the mystery surrounding the human proteome posed a major challenge. Despite not being largely involved in the Human Genome Project, the Indian scientific community contributed towards proteomic research along with the global community. Currently, more than 76 research/academic institutes and nearly 145 research labs are involved in core proteomic research across India. The Indian researchers have been major contributors in drafting the "human proteome map" along with international efforts. In addition to this, virtual proteomics labs, proteomics courses and remote triggered proteomics labs have helped to overcome the limitations of proteomics education posed due to expensive lab infrastructure. The establishment of Proteomics Society, India (PSI) has created a platform for the Indian proteomic researchers to share ideas, research collaborations and conduct annual conferences and workshops. Indian proteomic research is really moving forward with the global proteomics community in a quest to solve the mysteries of proteomics. A draft map of the human proteome enhances the enthusiasm among intellectuals to promote proteomic research in India to the world.This article is part of a Special Issue entitled: Proteomics in India. Copyright © 2015 Elsevier B.V. All rights reserved.

Members of a new subgroup of Streptococcus anginosus harbor virulence related genes previously observed in Streptococcus pyogenes.

PubMed

Babbar, Anshu; Kumar, Venkatesan Naveen; Bergmann, René; Barrantes, Israel; Pieper, Dietmar H; Itzek, Andreas; Nitsche-Schmitz, D Patric

2017-04-01

Conventionally categorized as commensals, the Streptococci of the species S. anginosus are facultative human pathogens that are difficult to diagnose and often overlooked. Furthermore, detailed investigation and diagnosis of S. anginosus infections is hampered by unexplored taxonomy and widely elusive molecular pathogenesis. To explore their pathogenic potential, S. anginosus isolates collected from patients of two geographical locations (Vellore, India and Leipzig, Germany) were subjected to multi-locus sequence analysis (MLSA). This analysis revealed the potential presence of a new distinct clade of the species S. anginosus, tentatively termed here as genomosubspecies vellorensis. A complementary PCR-based screening for S. pyogenes virulence factor as well as antibiotic resistance genes revealed not only the presence of superantigen- and extracellular DNase coding genes identical to corresponding genes of S. pyogenes, but also of erythromycin and tetracycline resistance genes in the genomes of the analyzed S. anginosus isolates, thus posing a matter of significant health concern. Identification of new pathogenic S. anginosus strains capable of causing difficult to treat infections may pose additional challenges to the diagnosis and treatment of Streptococcus based infections. Copyright © 2017 Elsevier GmbH. All rights reserved.

Cumulative risk assessment lessons learned: a review of case studies and issue papers.

PubMed

Gallagher, Sarah S; Rice, Glenn E; Scarano, Louis J; Teuschler, Linda K; Bollweg, George; Martin, Lawrence

2015-02-01

Cumulative risk assessments (CRAs) examine potential risks posed by exposure to multiple and sometimes disparate environmental stressors. CRAs are more resource intensive than single chemical assessments, and pose additional challenges and sources of uncertainty. CRAs may examine the impact of several factors on risk, including exposure magnitude and timing, chemical mixture composition, as well as physical, biological, or psychosocial stressors. CRAs are meant to increase the relevance of risk assessments, providing decision makers with information based on real world exposure scenarios that improve the characterization of actual risks and hazards. The U.S. Environmental Protection Agency has evaluated a number of CRAs, performed by or commissioned for the Agency, to seek insight into CRA concepts, methods, and lessons learned. In this article, ten case studies and five issue papers on key CRA topics are examined and a set of lessons learned are identified for CRA implementation. The lessons address the iterative nature of CRAs, importance of considering vulnerability, need for stakeholder engagement, value of a tiered approach, new methods to assess multiroute exposures to chemical mixtures, and the impact of geographical scale on approach and purpose. Copyright © 2014 Elsevier Ltd. All rights reserved.

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.

A Survey of Logic Formalisms to Support Mishap Analysis

NASA Technical Reports Server (NTRS)

Johnson, Chris; Holloway, C. M.

2003-01-01

Mishap investigations provide important information about adverse events and near miss incidents. They are intended to help avoid any recurrence of previous failures. Over time, they can also yield statistical information about incident frequencies that helps to detect patterns of failure and can validate risk assessments. However, the increasing complexity of many safety critical systems is posing new challenges for mishap analysis. Similarly, the recognition that many failures have complex, systemic causes has helped to widen the scope of many mishap investigations. These two factors have combined to pose new challenges for the analysis of adverse events. A new generation of formal and semi-formal techniques have been proposed to help investigators address these problems. We introduce the term mishap logics to collectively describe these notations that might be applied to support the analysis of mishaps. The proponents of these notations have argued that they can be used to formally prove that certain events created the necessary and sufficient causes for a mishap to occur. These proofs can be used to reduce the bias that is often perceived to effect the interpretation of adverse events. Others have argued that one cannot use logic formalisms to prove causes in the same way that one might prove propositions or theorems. Such mechanisms cannot accurately capture the wealth of inductive, deductive and statistical forms of inference that investigators must use in their analysis of adverse events. This paper provides an overview of these mishap logics. It also identifies several additional classes of logic that might also be used to support mishap analysis.

An individually randomized controlled trial to determine the effectiveness of the Women for Women International Programme in reducing intimate partner violence and strengthening livelihoods amongst women in Afghanistan: trial design, methods and baseline findings.

PubMed

Gibbs, Andrew; Corboz, Julienne; Shafiq, Mohammed; Marofi, Frozan; Mecagni, Anna; Mann, Carron; Karim, Fazal; Chirwa, Esnat; Maxwell-Jones, Charlotte; Jewkes, Rachel

2018-01-22

Intimate Partner Violence (IPV) is the most common form of violence in conflict and post-conflict settings, but there are few evaluations of interventions to prevent IPV in such settings. The Women for Women International (WfWI) intervention is a year-long combined economic and social empowerment intervention for marginalized women survivors of conflict. Primarily, it seeks to support women to achieve four key outcomes: women earn and save money; women improve their health and well-being; women influence decisions in their homes and communities; women connect to networks for support. The organization recognizes Violence Against Women and Girls (VAWG) as a significant barrier to women's empowerment and expects to see reduction in VAWG, and specifically IPV, as part of building women's social and economic empowerment. This program is being quantitatively evaluated through an individually randomized control trial amongst women in Afghanistan, with a 24-month follow up. A comparison of baseline characteristics of participants is also included as well as a discussion of implementation of the baseline research. There is a high demand amongst Afghan women for such interventions, and this posed challenges in completing the randomization and baseline. In addition, the complex security situation in Afghanistan also posed challenges. However, despite these issues, recruitment was successfully achieved and the arms were balanced on socio-demographic measures. The evaluation will contribute to the limited evidence base on interventions to prevent IPV in conflict-affected settings. NCT03236948 . Registered 28 July 2017, retrospectively registered.

Mapping the developmental constraints on working memory span performance.

PubMed

Bayliss, Donna M; Jarrold, Christopher; Baddeley, Alan D; Gunn, Deborah M; Leigh, Eleanor

2005-07-01

This study investigated the constraints underlying developmental improvements in complex working memory span performance among 120 children of between 6 and 10 years of age. Independent measures of processing efficiency, storage capacity, rehearsal speed, and basic speed of processing were assessed to determine their contribution to age-related variance in complex span. Results showed that developmental improvements in complex span were driven by 2 age-related but separable factors: 1 associated with general speed of processing and 1 associated with storage ability. In addition, there was an age-related contribution shared between working memory, processing speed, and storage ability that was important for higher level cognition. These results pose a challenge for models of complex span performance that emphasize the importance of processing speed alone.

Automatic Parameterization Strategy for Cardiac Electrophysiology Simulations

PubMed Central

Costa, Caroline Mendonca; Hoetzl, Elena; Rocha, Bernardo Martins; Prassl, Anton J; Plank, Gernot

2014-01-01

Driven by recent advances in medical imaging, image segmentation and numerical techniques, computer models of ventricular electrophysiology account for increasingly finer levels of anatomical and biophysical detail. However, considering the large number of model parameters involved parameterization poses a major challenge. A minimum requirement in combined experimental and modeling studies is to achieve good agreement in activation and repolarization sequences between model and experiment or patient data. In this study, we propose basic techniques which aid in determining bidomain parameters to match activation sequences. An iterative parameterization algorithm is implemented which determines appropriate bulk conductivities which yield prescribed velocities. In addition, a method is proposed for splitting the computed bulk conductivities into individual bidomain conductivities by prescribing anisotropy ratios. PMID:24729986

Hemorrhage and culture: management in the developing world and cultural implications for nursing care.

PubMed

Penney, D S

1991-01-01

In the industrialized world, technological resources and skilled personnel characterize the response to a hemorrhagic crisis. Such an efficient use of supplied technology stands in stark contrast to the responses toward a similar crisis when encountered in a developing country. In fact, attempting to manage a hemorrhage in a developing country may pose entanglements with economic, political, cultural, environmental, and medical obstacles. The uniqueness of this task and its challenges to the health professional are presented to provide nurses in advanced societies with a basic understanding of principles involved in managing hemorrhage in less-than-ideal circumstances. In addition, cultural care considerations are briefly described as they relate to the nursing role in the developing world.

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

NASA Technical Reports Server (NTRS)

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

1992-01-01

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

Adaptation of commercial biomarker kits and proposal for 'drug development kits' to support bioanalysis: call for action.

PubMed

Islam, Rafiqul; Kar, Sumit; Islam, Clarinda; Farmen, Raymond

2018-06-01

There has been an increased use of commercial kits for biomarker measurement, commensurate with the increased demand for biomarkers in drug development. However, in most cases these kits do not meet the quality attributes for use in regulated environment. The process for adaptation of these kits can be frustrating, time consuming and resource intensive. In addition, a lack of harmonized guidance for the validation of biomarker poses a significant challenge in the adaptation of kits in a regulated environment. The purpose of this perspective is to propose a tiered approach to commercial drug development kits with clearly defined quality attributes and to demonstrate how these kits can be adapted to perform analytical validation in a regulated environment.

Workshop on Spanning Regional-to-Global Pollution

NASA Technical Reports Server (NTRS)

Thompson, Anne M.; Newman, Paul A.; Gleason, James F.; Brune, William H.; Dickerson, Russell R.

2002-01-01

Pollution is often considered a localized phenomenon, but it is now clear that it travels from region-to-region, country to country, and even continent to continent. In addition to urban pollution in developed countries, large emissions from developing nations and large-scale biomass fires add to the global pollution burden. Ozone and aerosols are two components of pollution that contribute to radiative forcing of the earth s climate. In turn, as climate changes, rates of chemical and microphysical reactions may be perturbed. Considering the earth as a coupled chemical-microphysical-climate system poses challenges for models and observations alike. These issues were the topic of a Workshop held in May 2002 at NASA GSFC s Laboratory for Atmospheres. Highlights of the Workshop are summarized in this article.

Augmenting the Deliberative Method for Ranking Risks.

PubMed

Susel, Irving; Lasley, Trace; Montezemolo, Mark; Piper, Joel

2016-01-01

The Department of Homeland Security (DHS) characterized and prioritized the physical cross-border threats and hazards to the nation stemming from terrorism, market-driven illicit flows of people and goods (illegal immigration, narcotics, funds, counterfeits, and weaponry), and other nonmarket concerns (movement of diseases, pests, and invasive species). These threats and hazards pose a wide diversity of consequences with very different combinations of magnitudes and likelihoods, making it very challenging to prioritize them. This article presents the approach that was used at DHS to arrive at a consensus regarding the threats and hazards that stand out from the rest based on the overall risk they pose. Due to time constraints for the decision analysis, it was not feasible to apply multiattribute methodologies like multiattribute utility theory or the analytic hierarchy process. Using a holistic approach was considered, such as the deliberative method for ranking risks first published in this journal. However, an ordinal ranking alone does not indicate relative or absolute magnitude differences among the risks. Therefore, the use of the deliberative method for ranking risks is not sufficient for deciding whether there is a material difference between the top-ranked and bottom-ranked risks, let alone deciding what the stand-out risks are. To address this limitation of ordinal rankings, the deliberative method for ranking risks was augmented by adding an additional step to transform the ordinal ranking into a ratio scale ranking. This additional step enabled the selection of stand-out risks to help prioritize further analysis. © 2015 Society for Risk Analysis.

Blinded evaluation of farnesoid X receptor (FXR) ligands binding using molecular docking and free energy calculations

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.

Practical Considerations and Challenges Involved in Surfactant Enhanced Bioremediation of Oil

PubMed Central

Mohanty, Sagarika; Jasmine, Jublee

2013-01-01

Surfactant enhanced bioremediation (SEB) of oil is an approach adopted to overcome the bioavailability constraints encountered in biotransformation of nonaqueous phase liquid (NAPL) pollutants. Fuel oils contain n-alkanes and other aliphatic hydrocarbons, monoaromatics, and polynuclear aromatic hydrocarbons (PAHs). Although hydrocarbon degrading cultures are abundant in nature, complete biodegradation of oil is rarely achieved even under favorable environmental conditions due to the structural complexity of oil and culture specificities. Moreover, the interaction among cultures in a consortium, substrate interaction effects during the degradation and ability of specific cultures to alter the bioavailability of oil invariably affect the process. Although SEB has the potential to increase the degradation rate of oil and its constituents, there are numerous challenges in the successful application of this technology. Success is dependent on the choice of appropriate surfactant type and dose since the surfactant-hydrocarbon-microorganism interaction may be unique to each scenario. Surfactants not only enhance the uptake of constituents through micellar solubilization and emulsification but can also alter microbial cell surface characteristics. Moreover, hydrocarbons partitioned in micelles may not be readily bioavailable depending on the microorganism-surfactant interactions. Surfactant toxicity and inherent biodegradability of surfactants may pose additional challenges as discussed in this review. PMID:24350261

Integration of Sparse Multi-modality Representation and Geometrical Constraint for Isointense Infant Brain Segmentation

PubMed Central

Wang, Li; Shi, Feng; Li, Gang; Lin, Weili; Gilmore, John H.; Shen, Dinggang

2014-01-01

Segmentation of infant brain MR images is challenging due to insufficient image quality, severe partial volume effect, and ongoing maturation and myelination process. During the first year of life, the signal contrast between white matter (WM) and gray matter (GM) in MR images undergoes inverse changes. In particular, the inversion of WM/GM signal contrast appears around 6–8 months of age, where brain tissues appear isointense and hence exhibit extremely low tissue contrast, posing significant challenges for automated segmentation. In this paper, we propose a novel segmentation method to address the above-mentioned challenge based on the sparse representation of the complementary tissue distribution information from T1, T2 and diffusion-weighted images. Specifically, we first derive an initial segmentation from a library of aligned multi-modality images with ground-truth segmentations by using sparse representation in a patch-based fashion. The segmentation is further refined by the integration of the geometrical constraint information. The proposed method was evaluated on 22 6-month-old training subjects using leave-one-out cross-validation, as well as 10 additional infant testing subjects, showing superior results in comparison to other state-of-the-art methods. PMID:24505729

Integration of sparse multi-modality representation and geometrical constraint for isointense infant brain segmentation.

PubMed

Wang, Li; Shi, Feng; Li, Gang; Lin, Weili; Gilmore, John H; Shen, Dinggang

2013-01-01

Segmentation of infant brain MR images is challenging due to insufficient image quality, severe partial volume effect, and ongoing maturation and myelination process. During the first year of life, the signal contrast between white matter (WM) and gray matter (GM) in MR images undergoes inverse changes. In particular, the inversion of WM/GM signal contrast appears around 6-8 months of age, where brain tissues appear isointense and hence exhibit extremely low tissue contrast, posing significant challenges for automated segmentation. In this paper, we propose a novel segmentation method to address the above-mentioned challenge based on the sparse representation of the complementary tissue distribution information from T1, T2 and diffusion-weighted images. Specifically, we first derive an initial segmentation from a library of aligned multi-modality images with ground-truth segmentations by using sparse representation in a patch-based fashion. The segmentation is further refined by the integration of the geometrical constraint information. The proposed method was evaluated on 22 6-month-old training subjects using leave-one-out cross-validation, as well as 10 additional infant testing subjects, showing superior results in comparison to other state-of-the-art methods.

Strategies to enhance patient recruitment and retention in research involving patients with a first episode of mental illness.

PubMed

Furimsky, Ivana; Cheung, Amy H; Dewa, Carolyn S; Zipursky, Robert B

2008-11-01

Recruitment and retention of research participants is often the most labor-intensive and difficult component of clinical trials. Poor recruitment and retention frequently pose as a major barrier in the successful completion of clinical trials. In fact, many studies are prematurely terminated, or their findings questioned due to low recruitment and retention rates. The conduct of clinical trials involving youth with a first episode of mental illness comes with additional challenges in recruitment and retention including barriers associated with engagement and family involvement. To develop effective early interventions for first episode mental illness, it is necessary to develop strategies to enhance recruitment and retention in this patient population. This article presents the recruitment and retention challenges experienced in two clinical trials: one involving participants experiencing a first episode of depression and one involving participants experiencing a first episode psychosis. Challenges with recruitment and retention are identified and reviewed at both the patient level and clinician level. Strategies that were implemented to enhance recruitment and retention in these two studies are also discussed. Finally, ethical issues to consider when implementing these strategies are also highlighted.

Cannabis for Chronic Pain: Challenges and Considerations.

PubMed

Romero-Sandoval, E Alfonso; Fincham, Jack E; Kolano, Ashley L; Sharpe, Brandi N; Alvarado-Vázquez, P Abigail

2018-06-01

The National Academies of Sciences, Engineering, and Medicine has found substantial evidence that cannabis (plant) is effective for the treatment of chronic pain in adults, and moderate evidence that oromucosal cannabinoids (extracts, especially nabiximols) improve short-term sleep disturbances in chronic pain. The paradoxical superiority of the cannabis plant over cannabinoid molecules represents a challenge for the medical community and the established processes that define modern pharmacy. The expanding and variable legalization of cannabis in multiple states nationwide represents an additional challenge for patients and the medical community because recreational and medicinal cannabis are irresponsibly overlapped. Cannabis designed for recreational use (containing high levels of active ingredients) is increasingly available to patients with chronic pain who do not find relief with current pharmacologic entities, which exposes patients to potential harm. This article analyzes the available scientific evidence to address controversial questions that the current state of cannabis poses for health care professionals and chronic pain patients and sets the basis for a more open discussion about the role of cannabis in modern medicine for pain management. A critical discussion on these points, the legal status of cannabis, and considerations for health care providers is presented. © 2018 Pharmacotherapy Publications, Inc.

EUV tools: hydrogen gas purification and recovery strategies

NASA Astrophysics Data System (ADS)

Landoni, Cristian; Succi, Marco; Applegarth, Chuck; Riddle Vogt, Sarah

2015-03-01

The technological challenges that have been overcome to make extreme ultraviolet lithography (EUV) a reality have been enormous1. This vacuum driven technology poses significant purity challenges for the gases employed for purging and cleaning the scanner EUV chamber and source. Hydrogen, nitrogen, argon and ultra-high purity compressed dry air (UHPCDA) are the most common gases utilized at the scanner and source level. Purity requirements are tighter than for previous technology node tools. In addition, specifically for hydrogen, EUV tool users are facing not only gas purity challenges but also the need for safe disposal of the hydrogen at the tool outlet. Recovery, reuse or recycling strategies could mitigate the disposal process and reduce the overall tool cost of operation. This paper will review the types of purification technologies that are currently available to generate high purity hydrogen suitable for EUV applications. Advantages and disadvantages of each purification technology will be presented. Guidelines on how to select the most appropriate technology for each application and experimental conditions will be presented. A discussion of the most common approaches utilized at the facility level to operate EUV tools along with possible hydrogen recovery strategies will also be reported.

Diversity: The business case for and benefits of

NASA Astrophysics Data System (ADS)

Jones, M. B.

2013-05-01

Many Federal Agencies have 'workforce development' programs that focus on preparing the next generation of scientists and engineers at the graduate and undergraduate level. Several of the science Agencies (e.g., NASA, NOAA, EPA, etc.), have programs that support students in many of the diverse disciplines that are unique to those Agency missions. While financial support certainly is critical to assist students in the STEM and other fields, professional development is just as important to equip students with a balanced arsenal of tactics to be successful professionals in the STEM workforce of today. Understanding perceptions and managing expectations are learnable skills that do not necessarily come with project funding. Finding life balance as one moves through a STEM career path poses unique challenges that require a certain skill set that is not always intuitive. Some of those challenges include: selecting grad or post doc positions (negotiating to a family's advantage); balancing work and family commitments; and dealing with employer/advisor perceptions and expectations. Since the scientific enterprise requires multiple perspectives to flourish (e.g., peer review), many of the above mentioned challenges require additional skill in negotiating interactions with individuals from a variety of backgrounds… with as many perspectives.

An Analysis of the Supports and Constraints for Scientific Discussion in High School Project-Based Science

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…

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…

Limited Knowledge of Fraction Representations Differentiates Middle School Students with Mathematics Learning Disability (Dyscalculia) versus Low Mathematics Achievement

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…

Overview of contemporary issues of forest research and management in China

Treesearch

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…

Three Essays on Education Policy Empirical Analyses of the Challenges and Opportunities with For-Profit Colleges, Military Enlistment and Immigration

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…

Three Essays on Education Policy: Empirical Analyses of the Challenges and Opportunities with For-Profit Colleges, Military Enlistment and Immigration. PRGS Dissertation

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…

If the Shoe Doesn't Fit: A Case and a Place for Collaborative Learning for Music Practice in Higher Education

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…

The Perils of a Lack of Student Engagement: Reflections of a "Lonely, Brave, and Rather Exposed" Online Instructor

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…

A survey of big data research

PubMed Central

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

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…

Going beyond the Fab Five: Helping Students Cope with the Unique Linguistic Challenges of Expository Reading in Intermediate Grades

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…

Can Psychopathology at Age 7 Be Predicted from Clinical Observation at One Year? Evidence from the ALSPAC Cohort

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…

Successes and challenges in a novel doctoral program in systems agriculture: a case example.

PubMed

Lust, D; Topliff, D; Deotte, R

2010-01-01

A doctoral program in Systems Agriculture was initiated at West Texas A&M University, Canyon, TX, in September, 2003. The stated objective of the program was "..to prepare leaders for the agricultural industry that are trained in a multidisciplinary, research-based curriculum that emphasizes a systems approach to problem solving". The program offers a single doctoral degree in Agriculture and accepts qualified students with a master's or professional degree in agricultural or related disciplines. Courses related to systems methodologies, leadership, agricultural economics, plant and soil science, and animal science are required. Additional program requirements include a systems research project and dissertation, leadership training, and written and oral exams. The program has exceeded enrollment and graduation targets, suggesting interest in this approach to a doctoral degree. Students have entered the program with M.S. backgrounds in education, traditional agricultural disciplines, veterinary medicine, business, and physics. Graduates have gained employment in industry, university teaching and research, government research/administration, and extension. Doctoral student projects in systems agriculture contributed to curriculum changes and to the conceptual framework adopted by a multi-state research group. Designing and teaching courses for students with diverse backgrounds has been challenging. Development of a common understanding of systems agriculture was identified by a third-party program review as an issue for faculty. Development and maintenance of program standards and administrative procedures posed additional challenges. Leadership, administrative support, and timely and continuing program assessment are suggested as necessary components for a nontraditional doctoral program.

Integrating Remote Sensing Data with Socioeconomic Data: Sensitivity, Confidentiality, Privacy, and Intellectual Property Challenges

NASA Astrophysics Data System (ADS)

Downs, R. R.; Adamo, S. B.

2014-12-01

The integration of remote sensing data with socioeconomic data presents new opportunities for scientific discovery and analysis that can improve understanding of the environmental sustainability issues that society faces today. Such integrated data products and services can be used to study interdisciplinary issues by investigators representing various disciplines. In addition to the scientific benefits that can be attained by integrating remote sensing data with socioeconomic data, the integration of these data also present challenges that reflect the complex issues that arise when sharing and integrating different types of science data. When integrating one or more datasets that contain sensitive information, data producers need to be aware of the limitations that have been placed upon the data to protect private property, species or other inhabitants that reside on the property, or restricted information about a particular location. Similarly, confidentiality and privacy issues are a concern for data that have been collected about individual humans and families who have volunteered to serve as human research subjects or whose personal information may have been collected without their knowledge. In addition, intellectual property rights that are associated with a particular dataset may prevent integration with other data or pose constraints on the use of the resulting data products or services. These challenges will be described along with approaches that can be applied to address them when planning projects that involve the integration of remote sensing data with socioeconomic data.

Unconventional combinations of prospective parents: ethical challenges faced by IVF providers.

PubMed

Klitzman, Robert

2017-02-28

Professional guidelines have addressed ethical dilemmas posed by a few types of nontraditional procreative arrangements (e.g., gamete donations between family members), but many questions arise regarding how providers view and make decisions about these and other such arrangements. Thirty-seven ART providers and 10 patients were interviewed in-depth for approximately 1 h each. Interviews were systematically analyzed. Providers faced a range of challenges and ethical dilemmas concerning both the content and the process of decisions about requests for unconventional interfamilial and other reproductive combinations. Providers vary in how they respond - what they decide, who exactly decides (e.g., an ethics committee or not), and how - often undergoing complex decision-making processes. These combinations can involve creating or raising the child, and can shift over time - from initial ART treatment through to the child's birth. Patients' requests can vary from fully established to mere possibilities. Arrangements may also be unstable, fluid, or unexpected, posing challenges. Difficulties emerge concerning not only familial but social, combinations (e.g., between friends). These arrangements can involve blurry and confusing roles, questions about the welfare of the unborn child, and unanticipated and unfamiliar questions about how to weigh competing moral and scientific concerns - e.g., the autonomy of the individuals involved, and the potential risks and benefits. Clinicians may feel that these requests do not "smell right"; and at first respond with feelings of "yuck," and only later, carefully and explicitly consider the ethical principles involved. Proposed arrangements may, for instance, initially be felt to involve consanguineous individuals, but not in fact do so. Obtaining and verifying full and appropriate informed consent can be difficult, given implicit familial and/or cultural expectations and senses of duty. Social attitudes are changing, yet patients' views of these issues may also vary, based on their cultural backgrounds. These data, the first to examine how clinicians make decisions about unconventional reproductive arrangements, highlight several critical ethical questions and ambiguities, and variations in clinicians' responses. While several professional guidelines exist, the current data highlight additional challenges, and have vital implications for improving future guidelines, practice, education and research. Not applicable.

SRTM Stereo Pair with Landsat Overlay: Los Angeles to San Joaquin Valley, California

NASA Image and Video Library

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.

PubMed

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.

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...

Contaminated Sediment Core Profiling

EPA Science Inventory

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 ...

Rethinking the globalisation of problem-based learning: how culture challenges self-directed learning.

PubMed

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.

PubMed

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.

Ethics creep or governance creep? Challenges for Australian Human Research Ethics Committees (HRECS).

PubMed

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

PubMed Central

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.

Hepatitis B Virus Infection in Tanzania: Current Status and Challenges

PubMed Central

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

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?

PubMed

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.

Green Flight Challenge

NASA Image and Video Library

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)

Challenges in Reproducibility, Replicability, and Comparability of Computational Models and Tools for Neuronal and Glial Networks, Cells, and Subcellular Structures.

PubMed

Manninen, Tiina; Aćimović, Jugoslava; Havela, Riikka; Teppola, Heidi; Linne, Marja-Leena

2018-01-01

The possibility to replicate and reproduce published research results is one of the biggest challenges in all areas of science. In computational neuroscience, there are thousands of models available. However, it is rarely possible to reimplement the models based on the information in the original publication, let alone rerun the models just because the model implementations have not been made publicly available. We evaluate and discuss the comparability of a versatile choice of simulation tools: tools for biochemical reactions and spiking neuronal networks, and relatively new tools for growth in cell cultures. The replicability and reproducibility issues are considered for computational models that are equally diverse, including the models for intracellular signal transduction of neurons and glial cells, in addition to single glial cells, neuron-glia interactions, and selected examples of spiking neuronal networks. We also address the comparability of the simulation results with one another to comprehend if the studied models can be used to answer similar research questions. In addition to presenting the challenges in reproducibility and replicability of published results in computational neuroscience, we highlight the need for developing recommendations and good practices for publishing simulation tools and computational models. Model validation and flexible model description must be an integral part of the tool used to simulate and develop computational models. Constant improvement on experimental techniques and recording protocols leads to increasing knowledge about the biophysical mechanisms in neural systems. This poses new challenges for computational neuroscience: extended or completely new computational methods and models may be required. Careful evaluation and categorization of the existing models and tools provide a foundation for these future needs, for constructing multiscale models or extending the models to incorporate additional or more detailed biophysical mechanisms. Improving the quality of publications in computational neuroscience, enabling progressive building of advanced computational models and tools, can be achieved only through adopting publishing standards which underline replicability and reproducibility of research results.

Challenges in Reproducibility, Replicability, and Comparability of Computational Models and Tools for Neuronal and Glial Networks, Cells, and Subcellular Structures

PubMed Central

Manninen, Tiina; Aćimović, Jugoslava; Havela, Riikka; Teppola, Heidi; Linne, Marja-Leena

2018-01-01

The possibility to replicate and reproduce published research results is one of the biggest challenges in all areas of science. In computational neuroscience, there are thousands of models available. However, it is rarely possible to reimplement the models based on the information in the original publication, let alone rerun the models just because the model implementations have not been made publicly available. We evaluate and discuss the comparability of a versatile choice of simulation tools: tools for biochemical reactions and spiking neuronal networks, and relatively new tools for growth in cell cultures. The replicability and reproducibility issues are considered for computational models that are equally diverse, including the models for intracellular signal transduction of neurons and glial cells, in addition to single glial cells, neuron-glia interactions, and selected examples of spiking neuronal networks. We also address the comparability of the simulation results with one another to comprehend if the studied models can be used to answer similar research questions. In addition to presenting the challenges in reproducibility and replicability of published results in computational neuroscience, we highlight the need for developing recommendations and good practices for publishing simulation tools and computational models. Model validation and flexible model description must be an integral part of the tool used to simulate and develop computational models. Constant improvement on experimental techniques and recording protocols leads to increasing knowledge about the biophysical mechanisms in neural systems. This poses new challenges for computational neuroscience: extended or completely new computational methods and models may be required. Careful evaluation and categorization of the existing models and tools provide a foundation for these future needs, for constructing multiscale models or extending the models to incorporate additional or more detailed biophysical mechanisms. Improving the quality of publications in computational neuroscience, enabling progressive building of advanced computational models and tools, can be achieved only through adopting publishing standards which underline replicability and reproducibility of research results. PMID:29765315

How Physical Processes are Informing River Management Actions at Marble Bluff Dam, Truckee River, Nevada

NASA Astrophysics Data System (ADS)

Bountry, J.; Godaire, J.; Bradley, D. N.

2017-12-01

At the terminus of the Truckee River into Pyramid Lake (Nevada, USA), upstream river management actions have dramatically reshaped the river landscape, posing significant challenges for the management of endangered aquatic species and maintenance of existing infrastructure. Within the last 100 years, upstream water withdrawal for human uses has resulted in a rapid lowering of Pyramid Lake which initiated up to 90 ft of channel incision. In 1976 Marble Bluff Dam was constructed to halt the upstream progression of channel incision and protect upstream agricultural lands, tribal resources, and infrastructure. Since construction an additional 40 ft of lake lowering and subsequent channel lowering now poses a potential risk to the structural integrity of the dam. The dynamic downstream river combined with ongoing reservoir sedimentation pose challenges to fish passage facilities that enable migration of numerous endangered cui-ui and threatened Lahontan Cutthroat Trout (LCT) to upstream spawning areas each year. These facilities include a fish lock at the dam, a fish bypass channel which allows fish to avoid the shallow delta area during low lake levels, and a meandering channel constructed by the Nature Conservancy to connect the bypass channel to the receding Pyramid Lake. The reservoir formed by Marble Bluff Dam has completely filled with sediment which impacts fish passage facilities. The original operating manual for the dam recommends year-round flushing of sediment through radial gates, but this can no longer be accomplished. During critical fish migration periods in the spring operators must ensure fish entrance channels downstream of the dam are not buried with released sediment and fish are not trapped in a portion of the reservoir full of sediment that would risk sending them back over the dam. To help inform future reservoir sediment and infrastructure management strategies, we bracket a range of potential river responses to lake level lowering and floods using historical trends, current field data, and hydraulic and sediment transport models. We present options for adaptive management for dam and reservoir sediment operations that incorporates monitoring of river processes to inform annual implementation strategies along with long-term planning.

Predictive Models and Computational Toxicology

EPA Science Inventory

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...

HSA, hospital planning: arena of conflict offers room for cooperation.

PubMed

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.

The Plan to Certify America.

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.

Challenges posed to the European pharmaceutical regulatory system by highly personalized medicines.

PubMed

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 ‡.

PubMed

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 and Challenges in the Transition to Adulthood: Views and Experiences of Young People with Learning Disabilities and Their Families

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.

PubMed

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.

Implementing the No Child Left Behind Act: Using Student Engagement to Improve Adolescent Literacy. NCREL Quick Key 10 Action Guide

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…

Tunable, Quantitative Fenton-RAFT Polymerization via Metered Reagent Addition.

PubMed

Nothling, Mitchell D; McKenzie, Thomas G; Reyhani, Amin; Qiao, Greg G

2018-05-10

A continuous supply of radical species is a key requirement for activating chain growth and accessing quantitative monomer conversions in reversible addition-fragmentation chain transfer (RAFT) polymerization. In Fenton-RAFT, activation is provided by hydroxyl radicals, whose indiscriminate reactivity and short-lived nature poses a challenge to accessing extended polymerization times and quantitative monomer conversions. Here, an alternative Fenton-RAFT procedure is presented, whereby radical generation can be finely controlled via metered dosing of a component of the Fenton redox reaction (H 2 O 2 ) using an external pumping system. By limiting the instantaneous flux of radicals and ensuring sustained radical generation over tunable time periods, metered reagent addition reduces unwanted radical "wasting" reactions and provides access to consistent quantitative monomer conversions with high chain-end fidelity. Fine tuning of radical concentration during polymerization is achieved simply via adjustment of reagent dose rate, offering significant potential for automation. This modular strategy holds promise for extending traditional RAFT initiation toward more tightly regulated radical concentration profiles and affords excellent prospects for the automation of Fenton-RAFT polymerization. © 2018 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

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.

Hysteresis and Phase Transitions in a Lattice Regularization of an Ill-Posed Forward-Backward Diffusion Equation

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.

Combining self- and cross-docking as benchmark tools: the performance of DockBench in the D3R Grand Challenge 2

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.

Double-blind, placebo-controlled food challenge in adults in everyday clinical practice: a reappraisal of their limitations and real indications.

PubMed

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.

Malignant Perivascular Epithelioid Cell Tumor (PEComa) of the Adrenal Gland: Report of a Rare Case Posing Diagnostic Challenge with the Role of Immunohistochemistry in the Diagnosis.

PubMed

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.

Causal inferences on the effectiveness of complex social programs: Navigating assumptions, sources of complexity and evaluation design challenges.

PubMed

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.

Mass-gathering Events: The Public Health Challenge of the Kumbh Mela 2013.

PubMed

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.

Addressing the psychosocial and communication challenges posed by radiological/nuclear terrorism: key developments since NCRP Report No. 138.

PubMed

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.

Dealing with innovation and costs in orthopedics: a conversation with Dane Miller. Interview by Lawton R Burns.

PubMed

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.

Mechanical properties of sheet metal components with local reinforcement produced by additive manufacturing

NASA Astrophysics Data System (ADS)

Ünsal, Ismail; Hama-Saleh, R.; Sviridov, Alexander; Bambach, Markus; Weisheit, A.; Schleifenbaum, J. H.

2018-05-01

New technological challenges like electro-mobility pose an increasing demand for cost-efficient processes for the production of product variants. This demand opens the possibility to combine established die-based manufacturing methods and innovative, dieless technologies like additive manufacturing [1, 2]. In this context, additive manufacturing technologies allow for the weight-efficient local reinforcement of parts before and after forming, enabling manufacturers to produce product variants from series parts [3]. Previous work by the authors shows that the optimal shape of the reinforcing structure can be determined using sizing optimization. Sheet metal parts can then be reinforced using laser metal deposition. The material used is a pearlite-reduced, micro-alloyed steel (ZE 630). The aim of this paper is to determine the effect of the additive manufacturing process on the material behavior and the mechanical properties of the base material and the resulting composite material. The parameters of the AM process are optimized to reach similar material properties in the base material and the build-up volume. A metallographic analysis of the parts is presented, where the additive layers, the base material and also the bonding between the additive layers and the base material are analyzed. The paper shows the feasibility of the approach and details the resulting mechanical properties and performance.

'She's my sister-in-law, my visitor, my friend' -- challenges of staff identity in home follow-up in an HIV trial in Western Kenya.

PubMed

Madiega, Philister Adhiambo; Jones, Gemma; Prince, Ruth Jane; Geissler, Paul Wenzel

2013-04-01

Identities ascribed to research staff in face-to-face encounters with participants have been raised as key ethical challenge in transnational health research. 'Misattributed' identities that do not just deviate from researchers' self-image, but obscure unequivocal aspects of researcher identity - e.g. that they are researchers - are a case of such ethical problem. Yet, the reasonable expectation of unconcealed identity can conflict with another ethical premise: confidentiality; this poses challenges to staff visiting participants at home. We explore these around a case study of 'follow-up' staff, observed during an ethnographic study of a Kenyan HIV 'trial community', which included participant observation, conversations, and interviews with staff (n = 79) and participants (n = 89). We found that because of the need to maintain confidentiality and because of some suspicions towards researchers, research staff drew upon alternative identities - presenting themselves to non-participants as relatives or friends, rather than as researchers. Several staff experienced this as necessary but uncomfortable. Simultaneously, staff and participants forged close relations in line with their fictional identities, which however also posed challenges because they entailed personal responsibilities that were difficult to live up to, due to limited resources, and the trial's limited duration. Similar challenges may arise in transnational HIV treatment programmes and should be explored further in that context. © 2013 Blackwell Publishing Ltd.

Baseline Face Detection, Head Pose Estimation, and Coarse Direction Detection for Facial Data in the SHRP2 Naturalistic Driving Study

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

Paone, Jeffrey R; Bolme, David S; Ferrell, Regina Kay

Keeping a driver focused on the road is one of the most critical steps in insuring the safe operation of a vehicle. The Strategic Highway Research Program 2 (SHRP2) has over 3,100 recorded videos of volunteer drivers during a period of 2 years. This extensive naturalistic driving study (NDS) contains over one million hours of video and associated data that could aid safety researchers in understanding where the driver s attention is focused. Manual analysis of this data is infeasible, therefore efforts are underway to develop automated feature extraction algorithms to process and characterize the data. The real-world nature, volume,more » and acquisition conditions are unmatched in the transportation community, but there are also challenges because the data has relatively low resolution, high compression rates, and differing illumination conditions. A smaller dataset, the head pose validation study, is available which used the same recording equipment as SHRP2 but is more easily accessible with less privacy constraints. In this work we report initial head pose accuracy using commercial and open source face pose estimation algorithms on the head pose validation data set.« less

Using highways during notice evacuations operations.

DOT National Transportation Integrated Search

2006-12-01

Evacuations may involve hundreds or hundreds of thousands of people. regardless of the numbers, in each and every instance, the transportation network plays a key role in evacuating people out of harms way. recognizing the unique challenges posed ...

Doing quantum theory at a liberal arts college

NASA Astrophysics Data System (ADS)

Schumacher, Benjamin

2012-02-01

An academic career at a liberal arts college poses some challenges for a researcher in quantum information and quantum foundations, most notably the lack of local collaborators and graduate students. Are there also complementary advantages and opportunities?

Data archiving and availability in an era of open science.

PubMed

Baker, Edward N

2017-01-01

The importance of preserving and making available the original experimental data underlying biological structural models is discussed, both for crystallography, where the raw data images pose particular challenges, and for other structure determination techniques.

Legal dimensions of neural antecedents to voluntary action.

PubMed

Patterson, Dennis

2014-01-01

This article considers the arguments of Nachev and Hacker in the context of claims that Libet's experiments regarding the readiness potential pose challenges for the criminal law, specifically for the distinction between voluntary and involuntary acts.

Seal Technology for Hypersonic Vehicle and Propulsion: An Overview

NASA Technical Reports Server (NTRS)

Steinetz, Bruce M.

2008-01-01

Hypersonic vehicles and propulsion systems pose an extraordinary challenge for structures and materials. Airframes and engines require lightweight, high-temperature materials and structural configurations that can withstand the extreme environment of hypersonic flight. Some of the challenges posed include very high temperatures, heating of the whole vehicle, steady-state and transient localized heating from shock waves, high aerodynamic loads, high fluctuating pressure loads, potential for severe flutter, vibration, and acoustic loads and erosion. Correspondingly high temperature seals are required to meet these aggressive requirements. This presentation reviews relevant seal technology for both heritage (e.g. Space Shuttle, X-15, and X-38) vehicles and presents several seal case studies aimed at providing lessons learned for future hypersonic vehicle seal development. This presentation also reviews seal technology developed for the National Aerospace Plane propulsion systems and presents several seal case studies aimed at providing lessons learned for future hypersonic propulsion seal development.

Factoring health equations comment on "do you recommend an interdisciplinary field to your graduate student?".

PubMed

Rhodes, Michael Grant

2013-08-01

The International Journal of Health Policy and Management (IJHPM) is a new journal that aims to stimulate not only inter-disciplinary research relating to health, but even an entire new generation of such journals. The challenges of improving human health worldwide clearly suggest 'why' such a journal is needed, but 'how' bridges and junctions across fields of study towards this end might be found poses other questions. From the agnosticism of many sciences with respect to human health, to the great faith others place in more esoteric movements for human well-being, both suggest finding common factors in the many equations that affect human health. Particularly, as it is typically defined professionally, it might pose more fundamental challenges than those which appear first. However, the first editorial and edition quietly assure that the journal is in good hands, and that the search for a new generation of journals has begun.

Inadequate performance measures affecting practices, organizations and outcomes of Ontario's family health teams.

PubMed

Ashcroft, Rachelle

2014-01-01

Emphasis on quantity as the main performance measure may be posing challenges for Family Health Team (FHT) practices and organizational structures. This study asked: What healthcare practices and organizational structures are encouraged by the FHT model? An exploratory qualitative design guided by discourse analysis was used. This paper presents findings from in-depth semi-structured interviews conducted with seven policy informants and 29 FHT leaders. Participants report that performance measures value quantity and are not inclusive of the broad scope of attributes that comprise primary healthcare. Performance measures do not appear to be accurately capturing the demand for healthcare services, or the actual amount of services being provided by FHTs. RESULTS suggest that unintended consequences of performance measures may be posing challenges to access and health outcomes. It is recommended that performance measures be developed and used to measure, support and encourage FHTs to achieve the goals of PHC. Copyright © 2014 Longwoods Publishing.

What does public health ethics tell (or not tell) us about intervening in non-communicable diseases?

PubMed

Upshur, Ross

2013-03-01

Obesity has been described as pandemic and a public health crisis. It has been argued that concerted research efforts are needed to enhance our understanding and develop effective interventions for the complex and multiple dimensions of the health challenges posed by obesity. This would provide a secure evidence base in order to justify clinical interventions and public policy. This paper critically examines these claims through the examination of models of public health and public health ethics. I argue that the concept of an effective public health intervention is unclear and underdeveloped and, as a consequence, normative frameworks reliant on meeting the effectiveness criterion may miss morally salient dimensions of the problems. I conclude by arguing for the need to consider both an ecological model of public health and inclusion of a critical public health ethics perspective for an adequate account of the public health challenges posed by obesity.

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.

Therapeutic Advances in HCV Genotype 1 Infection: Insights from the Society of Infectious Diseases Pharmacists.

PubMed

Deming, Paulina; Martin, Michelle T; Chan, Juliana; Dilworth, Thomas J; El-Lababidi, Rania; Love, Bryan L; Mohammad, Rima A; Nguyen, Amy; Spooner, Linda M; Wortman, Suzanne B

2016-02-01

Hepatitis C virus (HCV) is the most common blood-borne infection in the United States. The high morbidity and mortality due to untreated infection have prompted updated screening recommendations that now include one-time HCV screening for all patients born between 1945 and 1965, in addition to risk factor-based screening. Current guidelines recommend treatment for all patients with chronic HCV. Treatment for HCV genotype 1 has evolved dramatically since the approval of the direct-acting antivirals. The approval of ledipasvir-sofosbuvir, ombitasvir-paritaprevir-ritonavir and dasabuvir, and simeprevir with sofosbuvir has dramatically altered the treatment landscape. High sustained virologic response (SVR) rates favor treatment, yet access to care poses a challenge for patients and providers. Current and emerging data with new therapies indicate high SVR rates in treatment-naïve and treatment-experienced patients, including patients with cirrhosis and in other special populations. Additional data suggest the addition of ribavirin can decrease treatment duration without compromising SVR rates. Resistance is an increasing area of interest in HCV, with baseline mutations identified and the potential for the development of resistance-associate variants in patients undergoing treatment. Due to the rapid evolution of HCV treatment, pharmacists should address challenges and play an integral role in agent selection, dosing, drug interaction screening, adverse effect monitoring, and the coordination of treatment. Clinical application of the latest information will reduce patient risk and improve outcomes. © 2016 Pharmacotherapy Publications, Inc.

Emerging Water Contaminants: Technical, Legal and Policy Challenges

NASA Astrophysics Data System (ADS)

Deeb, R. A.; Kresic, N.; Laugier, M. C.; Kavanaugh, M. C.

2002-12-01

Approximately 120 new chemicals are created each year due to ever-improving industry and technology markets. Releases of new contaminants into the environment can occur during production, use and disposal of these chemicals thereby leading to potential contamination of water supply sources. Very few emerging contaminants are regulated. In addition, knowledge gaps regarding emerging contaminants include lack health effects, occurrence (either because these compounds are not measured or because concentrations are below detection limits of readily available analytical techniques) and fate and transport in the environment especially with regards to mobility and persistence. The sources of these compounds are numerous. One source is treated wastewater, which is re-injected into groundwater aquifers for indirect potable reuse purposes. Emerging compounds of concern can be classified in various classes. This presentation will focus on contaminants, which have emerged in the last 10 years including pharmaceuticals (antibiotics/drugs), personal care products (polycyclic musks), pesticides/herbicides, industrial solvents (1,4-dioxane), gasoline additives (MTBE), disinfection byproducts such as NDMA (N-nitrosodimethylamine), and inorganic compounds such as perchlorate and arsenic. This presentation will present technical, legal and legislative challenges posed by the presence of these contaminants in water. Background information including chemical's history of use, sources in the environments, nationwide occurrence, physical and chemical properties, behavior in the environment and technologies for removal from soil and water will be presented. In addition, case studies on MTBE, pharmaceuticals and personal care products, 1,4-dioxane, arsenic and NDMA will be discussed.

Underage drinking: does the minimum age drinking law offer enough protection?

PubMed

Green, Rivka; Jason, Hannah; Ganz, Debora

2015-05-01

Underage drinking is a significant problem in the US. It is responsible for several thousand mortalities and fatalities each year, both among minors and other members of society. Additionally, underage alcohol consumption produces a severe economic burden in the US. Introduction to alcohol in youth poses serious long-term risks for adolescents, including occupational, educational, and psychosocial impairments, and increases the risk for developing alcohol abuse disorders in adulthood. In order to address and mitigate this problem, the US has set a minimum age drinking law of 21 in all 50 states, and has implemented several supplementary laws limiting the possession and consumption of alcohol. Though these laws have successfully reduced underage drinking, several additional strategies are noteworthy, including preventative and intervention efforts incorporating environmental, individual, communal, and parental factors. The following literature review describes these concepts as they relate to underage drinking laws in the US. Directions for future research, interventions, and ongoing challenges related to the minimum drinking age in the US are also discussed.

Thermal transport in binary colloidal glasses: Composition dependence and percolation assessment

NASA Astrophysics Data System (ADS)

Ruckdeschel, Pia; Philipp, Alexandra; Kopera, Bernd A. F.; Bitterlich, Flora; Dulle, Martin; Pech-May, Nelson W.; Retsch, Markus

2018-02-01

The combination of various types of materials is often used to create superior composites that outperform the pure phase components. For any rational design, the thermal conductivity of the composite as a function of the volume fraction of the filler component needs to be known. When approaching the nanoscale, the homogeneous mixture of various components poses an additional challenge. Here, we investigate binary nanocomposite materials based on polymer latex beads and hollow silica nanoparticles. These form randomly mixed colloidal glasses on a sub-μ m scale. We focus on the heat transport properties through such binary assembly structures. The thermal conductivity can be well described by the effective medium theory. However, film formation of the soft polymer component leads to phase segregation and a mismatch between existing mixing models. We confirm our experimental data by finite element modeling. This additionally allowed us to assess the onset of thermal transport percolation in such random particulate structures. Our study contributes to a better understanding of thermal transport through heterostructured particulate assemblies.

IFT27, encoding a small GTPase component of IFT particles, is mutated in a consanguineous family with Bardet–Biedl syndrome

PubMed Central

Aldahmesh, Mohammed A.; Li, Yuanyuan; Alhashem, Amal; Anazi, Shams; Alkuraya, Hisham; Hashem, Mais; Awaji, Ali A.; Sogaty, Sameera; Alkharashi, Abdullah; Alzahrani, Saeed; Al Hazzaa, Selwa A.; Xiong, Yong; Kong, Shanshan; Sun, Zhaoxia; Alkuraya, Fowzan S.

2014-01-01

Bardet–Biedl syndrome (BBS) is an autosomal recessive ciliopathy with multisystem involvement. So far, 18 BBS genes have been identified and the majority of them are essential for the function of BBSome, a protein complex involved in transporting membrane proteins into and from cilia. Yet defects in the identified genes cannot account for all the BBS cases. The genetic heterogeneity of this disease poses significant challenge to the identification of additional BBS genes. In this study, we coupled human genetics with functional validation in zebrafish and identified IFT27 as a novel BBS gene (BBS19). This is the first time an intraflagellar transport (IFT) gene is implicated in the pathogenesis of BBS, highlighting the genetic complexity of this disease. PMID:24488770

Real-time quasi-3D tomographic reconstruction

NASA Astrophysics Data System (ADS)

Buurlage, Jan-Willem; Kohr, Holger; Palenstijn, Willem Jan; Joost Batenburg, K.

2018-06-01

Developments in acquisition technology and a growing need for time-resolved experiments pose great computational challenges in tomography. In addition, access to reconstructions in real time is a highly demanded feature but has so far been out of reach. We show that by exploiting the mathematical properties of filtered backprojection-type methods, having access to real-time reconstructions of arbitrarily oriented slices becomes feasible. Furthermore, we present , software for visualization and on-demand reconstruction of slices. A user of can interactively shift and rotate slices in a GUI, while the software updates the slice in real time. For certain use cases, the possibility to study arbitrarily oriented slices in real time directly from the measured data provides sufficient visual and quantitative insight. Two such applications are discussed in this article.

Diagnostic pitfalls in newborns and babies with blisters and erosions.

PubMed

Nischler, Elke; Klausegger, Alfred; Hüttner, Clemens; Pohla-Gubo, Gabriele; Diem, Anja; Bauer, Johann W; Hintner, Helmut

2009-01-01

Establishing the correct diagnosis in newborns presenting with blisters and erosions is not always a straightforward process. Many different disease entities including acquired (i.e., infectious, immunobullous, traumatic) and inherited disorders have to be taken into consideration. Similarities in clinical appearance, colonization and/or superinfections of preexisting skin lesions, as well as the absence of late changes in the neonate often pose significant diagnostic challenges. In this paper we discuss by giving examples the process of making an accurate diagnosis of blistering skin diseases in the neonatal period on the basis of a diagnostic algorithm. In addition, we provide an overview of the rational use and the limitations of laboratory procedures such as microbial testing, routine light microscopy, immunofluorescence antigen mapping, transmission electron microscopy, and molecular genetic analysis.

Anaerobic microbial dehalogenation of organohalides-state of the art and remediation strategies.

PubMed

Nijenhuis, Ivonne; Kuntze, Kevin

2016-04-01

Contamination and remediation of groundwater with halogenated organics and understanding of involved microbial reactions still poses a challenge. Over the last years, research in anaerobic microbial dehalogenation has advanced in many aspects providing information about the reaction, physiology of microorganisms as well as approaches to investigate the activity of microorganisms in situ. Recently published crystal structures of reductive dehalogenases (Rdh), heterologous expression systems and advanced analytical, proteomic and stable isotope approaches allow addressing the overall reaction and specific enzymes as well as co-factors involved during anaerobic microbial dehalogenation. In addition to Dehalococcoides spp., Dehalobacter and Dehalogenimonas strains have been recognized as important and versatile organohalide respirers. Together, these provide perspectives for integrated concepts allowing to improve and monitor in situ biodegradation. Copyright © 2015 Elsevier Ltd. All rights reserved.

Measurement-induced long-distance entanglement of superconducting qubits using optomechanical transducers

NASA Astrophysics Data System (ADS)

Černotík, Ondřej; Hammerer, Klemens

2016-07-01

Although superconducting systems provide a promising platform for quantum computing, their networking poses a challenge because they cannot be interfaced to light, the medium used to send quantum signals through channels at room temperature. We show that mechanical oscillators can mediate such coupling and light can be used to measure the joint state of two distant qubits. The measurement provides information on the total spin of the two qubits such that entangled qubit states can be postselected. Entanglement generation is possible without ground-state cooling of the mechanical oscillators for systems with optomechanical cooperativity moderately larger than unity; in addition, our setup tolerates a substantial transmission loss. The approach is scalable to the generation of multipartite entanglement and represents a crucial step towards quantum networks with superconducting circuits.

The Split-Brain Phenomenon Revisited: A Single Conscious Agent with Split Perception.

PubMed

Pinto, Yair; de Haan, Edward H F; Lamme, Victor A F

2017-11-01

The split-brain phenomenon is caused by the surgical severing of the corpus callosum, the main route of communication between the cerebral hemispheres. The classical view of this syndrome asserts that conscious unity is abolished. The left hemisphere consciously experiences and functions independently of the right hemisphere. This view is a cornerstone of current consciousness research. In this review, we first discuss the evidence for the classical view. We then propose an alternative, the 'conscious unity, split perception' model. This model asserts that a split brain produces one conscious agent who experiences two parallel, unintegrated streams of information. In addition to changing our view of the split-brain phenomenon, this new model also poses a serious challenge for current dominant theories of consciousness. Copyright © 2017 Elsevier Ltd. All rights reserved.

Latest recanalization techniques for complex superficial femoral artery occlusions.

PubMed

Gonzalez, L; Chen, A; Lin, P H; Pisimisis, G; Barshes, N R; Bechara, C F; Kougias, P

2012-08-01

Complex, long segment lesions of the superficial femoral artery (SFA) are common, occurring in 40% of patients with peripheral vascular disease. In particular, chronic total occlusions (CTOs) continue to pose a challenge in the endovascular management of SFA disease. Several conventional wire and catheter based techniques have been described including subintimal recanalization and retrograde techniques. In addition, advances in endovascular technology have led to the development of a series of new devices aimed specifically at facilitating the crossing of long segment SFA occlusions or establishing re-entry of the true lumen. Here we present an overview of the minimally invasive techniques used to recanalize CTOs of the SFA and the latest specialized devices available for both recanalization and re-entry, as well as a summary of the literature supporting their application.

Methoxyethanol, Ethoxyethanol, and Spectral Complexity

NASA Astrophysics Data System (ADS)

Westerfield, J. H.; Riffe, Erika; Phillips, Maria; Johnson, Erika; Shipman, Steven

2017-06-01

Over the last few years, we have been working to improve the AUTOFIT programpand extend it to work on more complex spectra, especially spectra collected near room temperature. In this talk, we will discuss the problem of spectral complexity and the challenges it poses for moving to increasingly complicated systems. This will be highlighted by the cases of methoxyethanol, in which AUTOFIT was able to easily extract contributions from the ground state and four vibrationally excited states, and ethoxyethanol, in which AUTOFIT had difficulty identifying more than the ground vibrational state without the assistance of additional double resonance measurements. Seifert, N.A., Finneran, I.A., Perez, C., Zaleski, D.P., Neill, J.L., Steber, A.L., Suenram, R.D., Lesarri, A., Shipman, S.T., Pate, B.H., J. Mol. Spec. 312, 13-21 (2015)

Management of penoscrotal extramammary Paget disease: case series and review of the literature

PubMed Central

Moretto, P.; Nair, V.J.; Hallani, S. El; Malone, S.; Belanger, E.; Morash, C.; Canil, C.M.

2013-01-01

Extramammary Paget disease (empd) is a rare, slow-growing neoplasm, considered to be an adenocarcinoma of the apocrine glands. In men, the penoscrotal region is the most commonly affected area. The disease can present as carcinoma in situ or as invasive disease that can subsequently metastasize to lymph nodes and distant sites. Because of the rarity of empd, the medical literature available to guide management of the disease is limited, particularly in patients with metastases. In addition, metastatic disease may pose a diagnostic challenge, because invasive cancer of the genitourinary or gastrointestinal tract can occur in association with empd. In the present case series, we describe our experience in treating penoscrotal empd with multimodality therapy, and we review the existing literature concerning its diagnosis and management. PMID:23904770

Tilapia (Oreochromis mossambicus) brain cells respond to hyperosmotic challenge by inducing myo-inositol biosynthesis

PubMed Central

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

Iran: Regional Perspectives and U.S. Policy

DTIC Science & Technology

2010-01-13

unwilling to publicly challenge Iran on the issue because of their economic dependence on or relationships with Iran...of Iran’s neighbors, like Iraq, and poses direct military threats to others, like Israel and Lebanon. It also directly challenges U.S. efforts to...reports that a former speaker of the Iranian parliament and then- aide to Iran’s Supreme Leader had referred to Bahrain as Iran’s 14th province sparked a

Testing Universal Design of a Public Media Website with Diverse Users.

PubMed

Chen, Weiqin; Kessel, Siri; Sanderson, Norun C; Tatara, Naoe

2016-01-01

Testing with users can identify more issues than other testing methods. Many researchers have argued for the importance of user testing in Universal Design. However, testing Universal Design with diverse users poses many challenges. In this paper we will share our experience with testing the Universal Design of a public media website with real users. We discuss the challenges faced and lessons learned in the process.

The Challenge of Repeating Success in a Changing World: Final Report on the Center for Employment Training Replication Sites

ERIC Educational Resources Information Center

Miller, Cynthia; Bos, Johannes M.; Porter, Kristin E.; Tseng, Fannie M.; Abe, Yasuyo

2005-01-01

Succeeding in the labor market depends now more than ever on having the right education and training. This reality poses a particular challenge for out-of-school youth, who are no longer connected to institutions designed to provide them with training and connect them to good jobs. The Center for Employment Training (CET) in San Jose, California,…

Migrated esophageal stent posing a challenge for ventilation.

PubMed

D'souza, Nita; Arbhi, Sachin; Dikshit, Amit; Ghadge, Murarji; Jha, Smriti

2017-01-01

Self-expandable esophageal stents are being commonly used for palliative treatment in advanced esophageal cancer patients to relieve dysphagia, prevent tracheoesophageal fistula, and facilitate symptomatic betterment. The modern covered stents reduce the ingrowth of the tumor but have seen an increase in the incidence of stent migrations. We report a rather complicated presentation of an esophageal stent for esophageal dilatation and a challenging management of a difficult tracheostomy.

Deep Space Exploration: Will We Be Ready? Infectious Diseases, Microgravity and Other Forces Affecting Health Pose Challenges for Humans Planning to Explore Space

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.

Winners, losers, and posers: The effect of power poses on testosterone and risk-taking following competition.

PubMed

Smith, Kristopher M; Apicella, Coren L

2017-06-01

A contribution to a special issue on Hormones and Human Competition. The effect of postural power displays (i.e. power poses) on hormone levels and decision-making has recently been challenged. While Carney et al. (2010) found that holding brief postural displays of power leads to increased testosterone, decreased cortisol and greater economic risk taking, this failed to replicate in a recent high-powered study (Ranehill et al. 2015). It has been put forward that subtle differences in social context may account for the differences in results. Power displays naturally occur within the context of competitions, as do changes in hormones, and researchers have yet to examine the effects of poses within this ecologically relevant context. Using a large sample of 247 male participants, natural winners and losers of a physical competition were randomly assigned to hold a low, neutral or high-power postural display. We found no main effect of pose type on testosterone, cortisol, risk or feelings of power. Winners assigned to a high-power pose had a relative, albeit small, rise in testosterone compared to winners who held neutral or low-power poses. For losers, we found little evidence that high-power poses lead to increased testosterone relative to those holding neutral or low-powered poses. If anything, the reverse was observed - losers had a reduction in testosterone after holding high-power poses. To the extent that changes in testosterone modulate social behaviors adaptively, it is possible that the relative reduction in testosterone observed in losers taking high-powered poses is designed to inhibit further "winner-like" behavior that could result in continued defeat and harm. Still, effects were small, multiple comparisons were made, and the results ran counter to our predictions. We thus treat these conclusions as preliminary. Copyright © 2016 Elsevier Inc. All rights reserved.

Design of a Nutrient Reclamation System for the Cultivation of Microalgae for Biofuel Production and Other Industrial Applications

NASA Astrophysics Data System (ADS)

Sandefur, Heather Nicole

Microalgal biomass has been identified as a promising feedstock for a number of industrial applications, including the synthesis of new pharmaceutical and biofuel products. However, there are several economic limitations associated with the scale up of existing algal production processes. Critical economic studies of algae-based industrial processes highlight the high cost of supplying essential nutrients to microalgae cultures. With microalgae cells having relatively high nitrogen contents (4 to 8%), the N fertilizer cost in industrial-scale production is significant. In addition, the disposal of the large volumes of cell residuals that are generated during product extraction stages can pose other economic challenges. While waste streams can provide a concentrated source of nutrients, concerns about the presence of biological contaminants and the expense of heat treatment pose challenges to processes that use wastewater as a nutrient source in microalgae cultures. The goal of this study was to evaluate the potential application of ultrafiltration technology to aid in the utilization of agricultural wastewater in the cultivation of a high-value microalgae strain. An ultrafiltration system was used to remove inorganic solids and biological contaminants from wastewater taken from a swine farm in Savoy, Arkansas. The permeate from the system was then used as the nutrient source for the cultivation of the marine microalgae Porphyridium cruentum. During the ultrafiltration system operation, little membrane fouling was observed, and permeate fluxes remained relatively constant during both short-term and long-term tests. The complete rejection of E. coli and coliforms from the wastewater was also observed, in addition to a 75% reduction in total solids, including inorganic materials. The processed permeate was shown to have very high concentrations of total nitrogen (695.6 mg L-1) and total phosphorus (69.1 mg L-1 ). In addition, the growth of P. cruentum was analyzed in a medium containing swine waste permeate, and was compared to P. cruentum growth in a control medium. A higher biomass productivity, lipid productivity, and lipid content were observed in the microalgae cultivated in the swine waste medium compared to that of the control medium. These results suggest that, through the use of ultrafiltration technology as an alternative to traditional heat treatment, agricultural wastewaters could be effectively utilized as a nutrient source for microalgae cultivation.

Exploration Design Challenge 2014

NASA Image and Video Library

2014-04-25

NASA’s Administrator, Charles Bolden (left), President/CEO of Lockheed Martin, Marillyn Hewson (right), and astronaut Rex Walheim (back row) 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)

Immigration and Health: Law, Policy, and Ethics.

PubMed

Parmet, Wendy E; Sainsbury-Wong, Lorianne; Prabhu, Maya

2017-03-01

Immigration poses numerous challenges for health professionals and public health lawyers. This article reviews these challenges. We begin by offering some background on immigration and health and then explain some of the reasons why immigrants are less likely than natives to have health insurance. Next we turn to a discussion of some of the particular challenges relating to the health care of refugees. We conclude by analyzing and rejecting some of the arguments that are made for discriminating against immigrants with respect to the provision of public health benefits and services.

Probabilistic visual and electromagnetic data fusion for robust drift-free sequential mosaicking: application to fetoscopy

PubMed Central

Tella-Amo, Marcel; Peter, Loic; Shakir, Dzhoshkun I.; Deprest, Jan; Iglesias, Juan Eugenio; Ourselin, Sebastien

2018-01-01

Abstract. The most effective treatment for twin-to-twin transfusion syndrome is laser photocoagulation of the shared vascular anastomoses in the placenta. Vascular connections are extremely challenging to locate due to their caliber and the reduced field-of-view of the fetoscope. Therefore, mosaicking techniques are beneficial to expand the scene, facilitate navigation, and allow vessel photocoagulation decision-making. Local vision-based mosaicking algorithms inherently drift over time due to the use of pairwise transformations. We propose the use of an electromagnetic tracker (EMT) sensor mounted at the tip of the fetoscope to obtain camera pose measurements, which we incorporate into a probabilistic framework with frame-to-frame visual information to achieve globally consistent sequential mosaics. We parametrize the problem in terms of plane and camera poses constrained by EMT measurements to enforce global consistency while leveraging pairwise image relationships in a sequential fashion through the use of local bundle adjustment. We show that our approach is drift-free and performs similarly to state-of-the-art global alignment techniques like bundle adjustment albeit with much less computational burden. Additionally, we propose a version of bundle adjustment that uses EMT information. We demonstrate the robustness to EMT noise and loss of visual information and evaluate mosaics for synthetic, phantom-based and ex vivo datasets. PMID:29487889

Enhancing watershed research capacity: the role of data management

USDA-ARS?s Scientific Manuscript database

Water resources are under growing pressure globally, and in the face of projected climate change, changes in precipitation frequency and intensity; evapotranspiration, runoff, and snowmelt pose severe societal challenges. Interdisciplinary environmental research across natural and social sciences to...

Vehicle-to-vehicle communications in mixed passenger-freight convoys : [research brief].

DOT National Transportation Integrated Search

2016-09-01

Freight traffic in California depends, to a large degree, on trucks, due to their flexibility in : visiting warehouses, distribution centers, and terminals. However, trucks pose major challenges : to traffic and road safety. Accidents involving truck...

New Tools for Investigating Chemical and Product Use

EPA Science Inventory

- The timely characterization of the human and ecological risk posed by thousands of existing and emerging commercial chemicals is a critical challenge - High throughput (HT) risk prioritization relies on hazard and exposure characterization - While advances have been made ...

Data management to enhance long-term watershed research capacity

USDA-ARS?s Scientific Manuscript database

Water resources are under growing pressure globally, and in the face of projected climate change, uncertainty about precipitation frequency and intensity; evapotranspiration, runoff, and snowmelt poses severe societal challenges. Interdisciplinary environmental research across natural and social sc...

Neurodiversity

ERIC Educational Resources Information Center

Jurecic, Ann

2007-01-01

Increasingly, autistic students are attending college, posing new challenges to writing instructors. In particular, such students may have trouble imagining readers' responses to their texts. Developing an appropriate pedagogy for these students may involve revisiting composition studies' tradition of cognitive research, while not abandoning more…

Sampling methods and data generation

USDA-ARS?s Scientific Manuscript database

The study of forensic microbiology is an inherent blend of forensic science and microbiology, and both disciplines have recently been undergoing rapid advancements in technology that are allowing for exciting new research avenues. The integration of two different disciplines poses challenges becaus...

E-Learning

ERIC Educational Resources Information Center

Buzzi, Marina, Ed.

2010-01-01

E-Learning is a vast and complex research topic that poses many challenges in every aspect: educational and pedagogical strategies and techniques and the tools for achieving them; usability, accessibility and user interface design; knowledge sharing and collaborative environments; technologies, architectures, and protocols; user activity…

Biofuels and Fisheries: Risks and Opportunities .

EPA Science Inventory

A rapidly developing biofuels industry in the U.S. and around the globe poses novel environmental challenges and opportunities, with implications for teh health and sustainability of fisheries. Changes in land uses and agricultural practices for production of biofuel feedstocks ...

A PERFORMANCE HISTORY OF THE BASE CATALYZED DECOMPOSITION (BCD) PROCESS

EPA Science Inventory

Remediation of halogenated organic compounds--such as polychlorinated biphenyls (PCBs), polychlorinated dibenzo-p-dioxins (PCDDs), and polychlorinated dibenzofurans (PCDFs)--poses a challenge because these compounds are resistant to microbial attack and to degradation by many com...

Robotic cardiac surgery: an anaesthetic challenge.

PubMed

Wang, Gang; Gao, Changqing

2014-08-01

Robotic cardiac surgery with the da Vinci robotic surgical system offers the benefits of a minimally invasive procedure, including a smaller incision and scar, reduced risk of infection, less pain and trauma, less bleeding and blood transfusion requirements, shorter hospital stay and decreased recovery time. Robotic cardiac surgery includes extracardiac and intracardiac procedures. Extracardiac procedures are often performed on a beating heart. Intracardiac procedures require the aid of peripheral cardiopulmonary bypass via a minithoracotomy. Robotic cardiac surgery, however, poses challenges to the anaesthetist, as the obligatory one-lung ventilation (OLV) and CO2 insufflation may reduce cardiac output and increase pulmonary vascular resistance, potentially resulting in hypoxaemia and haemodynamic compromise. In addition, surgery requires appropriate positioning of specialised cannulae such as an endopulmonary vent, endocoronary sinus catheter, and endoaortic clamp catheter under the guidance of transoesophageal echocardiography. Therefore, cardiac anaesthetists should have a working knowledge of these systems, OLV and haemodynamic support. Published by the BMJ Publishing Group Limited. For permission to use (where not already granted under a licence) please go to http://group.bmj.com/group/rights-licensing/permissions.

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

Fischer, Sean A.; Ueltschi, Tyler W.; El-Khoury, Patrick Z.

Carbon-hydrogen (C-H) vibration modes serve as key probes in the chemical identification of hydrocarbons and in vibrational sum-frequency generation (SFG) spectroscopy of hydrocarbons at the liquid/gas interface. Their assignments pose a challenge from a theoretical viewpoint. Here in this work, we present a detailed study of the C-H stretching region of dimethyl sulfoxide (DMSO) using a new Gaussian basis set- based ab initio molecular dynamics (AIMD) module that we have implemented in the NWChem computational chemistry program. By combining AIMD simulations and static normal mode analysis, we interpret experimental infrared and Raman spectra and explore the role of anharmonic effectsmore » in this system. Our anharmonic normal mode analysis of the in-phase and out-of-phase symmetric C-H stretching modes challenges the previous experimental assignment of the shoulder in the symmetric C-H stretching peak as an overtone or Fermi resonance. In addition, our AIMD simulations also show significant broadening of the in-phase symmetric C-H stretching resonance, which suggests that the experimentally observed shoulder is due to thermal broadening of the symmetric stretching resonance.« less

Nonprofit Human Milk Banking in the United States.

PubMed

Updegrove, Kimberly

2013-01-01

Human milk, widely understood to be beneficial for infants, can be lifesaving for preterm neonates, especially in reducing the risk of necrotizing enterocolitis. Donor human milk (DHM) is an option when mothers are unable to provide milk or have an inadequate supply for their infants. Nonprofit donor human milk banks are established to provide safe, processed human milk from milk donated by healthy lactating mothers who have undergone a rigorous screening process. These milk banks, operating under the auspices of the Human Milk Banking Association of North America, obtain, process, and dispense human milk under strict guidelines set by the association. Increasing the supply of donor human milk to meet a dramatic increase in demand poses a significant challenge for nonprofit milk banks. Efforts to increase supply nationwide include education of providers, use of social media to engage potential donors, and outreach to news media. In parallel, milk banks are establishing regional depots to collect donations, and additional milk banks are being developed. This article describes the current nonprofit milk bank industry in the United States, its challenges, and its future prospects. © 2013 by the American College of Nurse‐Midwives.

Visualization of metabolic interaction networks in microbial communities using VisANT 5.0

DOE PAGES

Granger, Brian R.; Chang, Yi -Chien; Wang, Yan; ...

2016-04-15

Here, the complexity of metabolic networks in microbial communities poses an unresolved visualization and interpretation challenge. We address this challenge in the newly expanded version of a software tool for the analysis of biological networks, VisANT 5.0. We focus in particular on facilitating the visual exploration of metabolic interaction between microbes in a community, e.g. as predicted by COMETS (Computation of Microbial Ecosystems in Time and Space), a dynamic stoichiometric modeling framework. Using VisANT's unique meta-graph implementation, we show how one can use VisANT 5.0 to explore different time-dependent ecosystem-level metabolic networks. In particular, we analyze the metabolic interaction networkmore » between two bacteria previously shown to display an obligate cross-feeding interdependency. In addition, we illustrate how a putative minimal gut microbiome community could be represented in our framework, making it possible to highlight interactions across multiple coexisting species. We envisage that the "symbiotic layout" of VisANT can be employed as a general tool for the analysis of metabolism in complex microbial communities as well as heterogeneous human tissues.« less

Multiple pruritic papules from lone star tick larvae bites.

PubMed

Fisher, Emily J; Mo, Jun; Lucky, Anne W

2006-04-01

Ticks are the second most common vectors of human infectious diseases in the world. In addition to their role as vectors, ticks and their larvae can also produce primary skin manifestations. Infestation by the larvae of ticks is not commonly recognized, with only 3 cases reported in the literature. The presence of multiple lesions and partially burrowed 6-legged tick larvae can present a diagnostic challenge for clinicians. We describe a 51-year-old healthy woman who presented to our clinic with multiple erythematous papules and partially burrowed organisms 5 days after exposure to a wooded area in southern Kentucky. She was treated with permethrin cream and the lesions resolved over the following 3 weeks without sequelae. The organism was later identified as the larva of Amblyomma species, the lone star tick. Multiple pruritic papules can pose a diagnostic challenge. The patient described herein had an unusually large number of pruritic papules as well as tick larvae present on her skin. Recognition of lone star tick larvae as a cause of multiple bites may be helpful in similar cases.

Visual navigation using edge curve matching for pinpoint planetary landing

NASA Astrophysics Data System (ADS)

Cui, Pingyuan; Gao, Xizhen; Zhu, Shengying; Shao, Wei

2018-05-01

Pinpoint landing is challenging for future Mars and asteroid exploration missions. Vision-based navigation scheme based on feature detection and matching is practical and can achieve the required precision. However, existing algorithms are computationally prohibitive and utilize poor-performance measurements, which pose great challenges for the application of visual navigation. This paper proposes an innovative visual navigation scheme using crater edge curves during descent and landing phase. In the algorithm, the edge curves of the craters tracked from two sequential images are utilized to determine the relative attitude and position of the lander through a normalized method. Then, considering error accumulation of relative navigation, a method is developed. That is to integrate the crater-based relative navigation method with crater-based absolute navigation method that identifies craters using a georeferenced database for continuous estimation of absolute states. In addition, expressions of the relative state estimate bias are derived. Novel necessary and sufficient observability criteria based on error analysis are provided to improve the navigation performance, which hold true for similar navigation systems. Simulation results demonstrate the effectiveness and high accuracy of the proposed navigation method.

Parallel Processing of Images in Mobile Devices using BOINC

NASA Astrophysics Data System (ADS)

Curiel, Mariela; Calle, David F.; Santamaría, Alfredo S.; Suarez, David F.; Flórez, Leonardo

2018-04-01

Medical image processing helps health professionals make decisions for the diagnosis and treatment of patients. Since some algorithms for processing images require substantial amounts of resources, one could take advantage of distributed or parallel computing. A mobile grid can be an adequate computing infrastructure for this problem. A mobile grid is a grid that includes mobile devices as resource providers. In a previous step of this research, we selected BOINC as the infrastructure to build our mobile grid. However, parallel processing of images in mobile devices poses at least two important challenges: the execution of standard libraries for processing images and obtaining adequate performance when compared to desktop computers grids. By the time we started our research, the use of BOINC in mobile devices also involved two issues: a) the execution of programs in mobile devices required to modify the code to insert calls to the BOINC API, and b) the division of the image among the mobile devices as well as its merging required additional code in some BOINC components. This article presents answers to these four challenges.

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

Granger, Brian R.; Chang, Yi -Chien; Wang, Yan

Here, the complexity of metabolic networks in microbial communities poses an unresolved visualization and interpretation challenge. We address this challenge in the newly expanded version of a software tool for the analysis of biological networks, VisANT 5.0. We focus in particular on facilitating the visual exploration of metabolic interaction between microbes in a community, e.g. as predicted by COMETS (Computation of Microbial Ecosystems in Time and Space), a dynamic stoichiometric modeling framework. Using VisANT's unique meta-graph implementation, we show how one can use VisANT 5.0 to explore different time-dependent ecosystem-level metabolic networks. In particular, we analyze the metabolic interaction networkmore » between two bacteria previously shown to display an obligate cross-feeding interdependency. In addition, we illustrate how a putative minimal gut microbiome community could be represented in our framework, making it possible to highlight interactions across multiple coexisting species. We envisage that the "symbiotic layout" of VisANT can be employed as a general tool for the analysis of metabolism in complex microbial communities as well as heterogeneous human tissues.« less