NASA Astrophysics Data System (ADS)
Jamaludin, A. S.; Hosokawa, A.; Furumoto, T.; Koyano, T.; Hashimoto, Y.
2018-03-01
Cutting process of difficult-to-cut material such as stainless steel, generates immensely excessive heat, which is one of the major causes related to shortening tool life and lower quality of surface finish. It is proven that application of cutting fluid during the cutting process of difficult-to-cut material is able to improve the cutting performance, but excessive application of cutting fluid leads to another problem such as increasing processing cost and environmental hazardous pollution of workplace. In the study, Extreme Cold Mist system is designed and tested along with various Minimum Quantity Lubrication (MQL) systems on turning process of stainless steel AISI 316. In the study, it is obtained that, Extreme Cold Mist system is able to reduce cutting force up to 60N and improve the surface roughness of the machined surface significantly.
Rosetta Structure Prediction as a Tool for Solving Difficult Molecular Replacement Problems.
DiMaio, Frank
2017-01-01
Molecular replacement (MR), a method for solving the crystallographic phase problem using phases derived from a model of the target structure, has proven extremely valuable, accounting for the vast majority of structures solved by X-ray crystallography. However, when the resolution of data is low, or the starting model is very dissimilar to the target protein, solving structures via molecular replacement may be very challenging. In recent years, protein structure prediction methodology has emerged as a powerful tool in model building and model refinement for difficult molecular replacement problems. This chapter describes some of the tools available in Rosetta for model building and model refinement specifically geared toward difficult molecular replacement cases.
Diagnostic approach of myocarditis: strike the golden mean.
Hazebroek, M R; Everaerts, K; Heymans, S
2014-02-01
Myocarditis is a challenging diagnosis due to the extreme diversity of clinical manifestations. The actual incidence of myocarditis is also difficult to determine as endomyocardial biopsy (EMB), the diagnostic gold standard, is used infrequently. Nevertheless, in up to 30 % of patients with biopsy-proven myocarditis, progression to dilated cardiomyopathy (DCM) can occur and is associated with a poor prognosis. Recent position statements of the European Society of Cardiology (ESC) and the American Heart Association vary widely with regard to indications for performing an EMB in these patients. This makes decision-making, in particular for general practitioners (GPs) and regional hospitals, difficult and unclear. Therefore, we will present a short summary of the ESC Working Group on Myocardial and Pericardial Diseases statement and our suggestions for GPs and regional hospitals for the diagnostic approach in patients with suspected myocarditis.
NASA Technical Reports Server (NTRS)
Smith, Matthew R.; Molthan, Andrew L.; Fuell, Kevin K.; Jedlovec, Gary J.
2012-01-01
SPoRT is a team of NASA/NOAA scientists focused on demonstrating the utility of NASA and future NOAA data and derived products on improving short-term weather forecasts. Work collaboratively with a suite of unique products and selected WFOs in an end-to-end transition activity. Stable funding from NASA and NOAA. Recognized by the science community as the "go to" place for transitioning experimental and research data to the operational weather community. Endorsed by NWS ESSD/SSD chiefs. Proven paradigm for transitioning satellite observations and modeling capabilities to operations (R2O). SPoRT s transition of NASA satellite instruments provides unique or higher resolution data products to complement the baseline suite of geostationary data available to forecasters. SPoRT s partnership with NWS WFOs provides them with unique imagery to support disaster response and local forecast challenges. SPoRT has years of proven experience in developing and transitioning research products to the operational weather community. SPoRT has begun work with CONUS and OCONUS WFOs to determine the best products for maximum benefit to forecasters. VIIRS has already proven to be another extremely powerful tool, enhancing forecasters ability to handle difficult forecasting situations.
Uncertainty in determining extreme precipitation thresholds
NASA Astrophysics Data System (ADS)
Liu, Bingjun; Chen, Junfan; Chen, Xiaohong; Lian, Yanqing; Wu, Lili
2013-10-01
Extreme precipitation events are rare and occur mostly on a relatively small and local scale, which makes it difficult to set the thresholds for extreme precipitations in a large basin. Based on the long term daily precipitation data from 62 observation stations in the Pearl River Basin, this study has assessed the applicability of the non-parametric, parametric, and the detrended fluctuation analysis (DFA) methods in determining extreme precipitation threshold (EPT) and the certainty to EPTs from each method. Analyses from this study show the non-parametric absolute critical value method is easy to use, but unable to reflect the difference of spatial rainfall distribution. The non-parametric percentile method can account for the spatial distribution feature of precipitation, but the problem with this method is that the threshold value is sensitive to the size of rainfall data series and is subjected to the selection of a percentile thus make it difficult to determine reasonable threshold values for a large basin. The parametric method can provide the most apt description of extreme precipitations by fitting extreme precipitation distributions with probability distribution functions; however, selections of probability distribution functions, the goodness-of-fit tests, and the size of the rainfall data series can greatly affect the fitting accuracy. In contrast to the non-parametric and the parametric methods which are unable to provide information for EPTs with certainty, the DFA method although involving complicated computational processes has proven to be the most appropriate method that is able to provide a unique set of EPTs for a large basin with uneven spatio-temporal precipitation distribution. The consistency between the spatial distribution of DFA-based thresholds with the annual average precipitation, the coefficient of variation (CV), and the coefficient of skewness (CS) for the daily precipitation further proves that EPTs determined by the DFA method are more reasonable and applicable for the Pearl River Basin.
As-built data capture of complex piping using photogrammetry technology
DOE Office of Scientific and Technical Information (OSTI.GOV)
Morray, J.P.; Ziu, C.G.
1995-11-01
Plant owners face an increasingly difficult and expensive task of updating drawings, both regarding the plant logic and physical layout. Through the use of photogrammetry technology, H-H spectrum has created a complete operating plant data capture service, with the result that the task of recording accurate plant configurations has become assured and economical. The technology has proven to be extremely valuable for the capture of complex piping configurations, as well as entire plant facilities, and yields accuracy within 1/4 inch. The method uses photographs and workstation technology to quickly document and compute the plant layout, with all components, regardless ofmore » size, included in the resulting model. The system has the capability to compute actual 3-D coordinates of any point based on previous triangulations, allowing for an immediate assessment of accuracy. This ensures a consistent level of accuracy, which is impossible to achieve in a manual approach. Due to the speed of the process, the approach is very important in hazardous/difficult environments such as nuclear power facilities or offshore platforms.« less
Adaptation of eastern whitepine provenances to planting sites
Maurice E., Jr. Demeritt; Peter W. Garrett
1996-01-01
Eastern white pine provenances from the extreme limits of the natural range of this species are changing from above- and below-average stability to average stability for height growth with increasing age. The regression method is useful for evaluating the stability of provenance to planting sites. The same general conclusions are reached for the performance at...
Optimization as a Tool for Consistency Maintenance in Multi-Resolution Simulation
NASA Technical Reports Server (NTRS)
Drewry, Darren T; Reynolds, Jr , Paul F; Emanuel, William R
2006-01-01
The need for new approaches to the consistent simulation of related phenomena at multiple levels of resolution is great. While many fields of application would benefit from a complete and approachable solution to this problem, such solutions have proven extremely difficult. We present a multi-resolution simulation methodology that uses numerical optimization as a tool for maintaining external consistency between models of the same phenomena operating at different levels of temporal and/or spatial resolution. Our approach follows from previous work in the disparate fields of inverse modeling and spacetime constraint-based animation. As a case study, our methodology is applied to two environmental models of forest canopy processes that make overlapping predictions under unique sets of operating assumptions, and which execute at different temporal resolutions. Experimental results are presented and future directions are addressed.
A deep learning framework to discern and count microscopic nematode eggs.
Akintayo, Adedotun; Tylka, Gregory L; Singh, Asheesh K; Ganapathysubramanian, Baskar; Singh, Arti; Sarkar, Soumik
2018-06-14
In order to identify and control the menace of destructive pests via microscopic image-based identification state-of-the art deep learning architecture is demonstrated on the parasitic worm, the soybean cyst nematode (SCN), Heterodera glycines. Soybean yield loss is negatively correlated with the density of SCN eggs that are present in the soil. While there has been progress in automating extraction of egg-filled cysts and eggs from soil samples counting SCN eggs obtained from soil samples using computer vision techniques has proven to be an extremely difficult challenge. Here we show that a deep learning architecture developed for rare object identification in clutter-filled images can identify and count the SCN eggs. The architecture is trained with expert-labeled data to effectively build a machine learning model for quantifying SCN eggs via microscopic image analysis. We show dramatic improvements in the quantification time of eggs while maintaining human-level accuracy and avoiding inter-rater and intra-rater variabilities. The nematode eggs are correctly identified even in complex, debris-filled images that are often difficult for experts to identify quickly. Our results illustrate the remarkable promise of applying deep learning approaches to phenotyping for pest assessment and management.
Leveraging the national cyberinfrastructure for biomedical research.
LeDuc, Richard; Vaughn, Matthew; Fonner, John M; Sullivan, Michael; Williams, James G; Blood, Philip D; Taylor, James; Barnett, William
2014-01-01
In the USA, the national cyberinfrastructure refers to a system of research supercomputer and other IT facilities and the high speed networks that connect them. These resources have been heavily leveraged by scientists in disciplines such as high energy physics, astronomy, and climatology, but until recently they have been little used by biomedical researchers. We suggest that many of the 'Big Data' challenges facing the medical informatics community can be efficiently handled using national-scale cyberinfrastructure. Resources such as the Extreme Science and Discovery Environment, the Open Science Grid, and Internet2 provide economical and proven infrastructures for Big Data challenges, but these resources can be difficult to approach. Specialized web portals, support centers, and virtual organizations can be constructed on these resources to meet defined computational challenges, specifically for genomics. We provide examples of how this has been done in basic biology as an illustration for the biomedical informatics community.
Leveraging the national cyberinfrastructure for biomedical research
LeDuc, Richard; Vaughn, Matthew; Fonner, John M; Sullivan, Michael; Williams, James G; Blood, Philip D; Taylor, James; Barnett, William
2014-01-01
In the USA, the national cyberinfrastructure refers to a system of research supercomputer and other IT facilities and the high speed networks that connect them. These resources have been heavily leveraged by scientists in disciplines such as high energy physics, astronomy, and climatology, but until recently they have been little used by biomedical researchers. We suggest that many of the ‘Big Data’ challenges facing the medical informatics community can be efficiently handled using national-scale cyberinfrastructure. Resources such as the Extreme Science and Discovery Environment, the Open Science Grid, and Internet2 provide economical and proven infrastructures for Big Data challenges, but these resources can be difficult to approach. Specialized web portals, support centers, and virtual organizations can be constructed on these resources to meet defined computational challenges, specifically for genomics. We provide examples of how this has been done in basic biology as an illustration for the biomedical informatics community. PMID:23964072
Approximate equiangular tight frames for compressed sensing and CDMA applications
NASA Astrophysics Data System (ADS)
Tsiligianni, Evaggelia; Kondi, Lisimachos P.; Katsaggelos, Aggelos K.
2017-12-01
Performance guarantees for recovery algorithms employed in sparse representations, and compressed sensing highlights the importance of incoherence. Optimal bounds of incoherence are attained by equiangular unit norm tight frames (ETFs). Although ETFs are important in many applications, they do not exist for all dimensions, while their construction has been proven extremely difficult. In this paper, we construct frames that are close to ETFs. According to results from frame and graph theory, the existence of an ETF depends on the existence of its signature matrix, that is, a symmetric matrix with certain structure and spectrum consisting of two distinct eigenvalues. We view the construction of a signature matrix as an inverse eigenvalue problem and propose a method that produces frames of any dimensions that are close to ETFs. Due to the achieved equiangularity property, the so obtained frames can be employed as spreading sequences in synchronous code-division multiple access (s-CDMA) systems, besides compressed sensing.
Overview of the biochemical and genetic processes in malignant mesothelioma*
de Assis, Leonardo Vinícius Monteiro; Isoldi, Mauro César
2014-01-01
Malignant mesothelioma (MM) is a highly aggressive form of cancer, has a long latency period, and is resistant to chemotherapy. It is extremely fatal, with a mean survival of less than one year. The development of MM is strongly correlated with exposure to asbestos and erionite, as well as to simian virus 40. Although various countries have banned the use of asbestos, MM has proven to be difficult to control and there appears to be a trend toward an increase in its incidence in the years to come. In Brazil, MM has not been widely studied from a genetic or biochemical standpoint. In addition, there have been few epidemiological studies of the disease, and the profile of its incidence has yet to be well established in the Brazilian population. The objective of this study was to review the literature regarding the processes of malignant transformation, as well as the respective mechanisms of tumorigenesis, in MM. PMID:25210967
Horii, Takuro; Tamura, Daiki; Morita, Sumiyo; Kimura, Mika; Hatada, Izuho
2013-09-30
Genome manipulation of human induced pluripotent stem (iPS) cells is essential to achieve their full potential as tools for regenerative medicine. To date, however, gene targeting in human pluripotent stem cells (hPSCs) has proven to be extremely difficult. Recently, an efficient genome manipulation technology using the RNA-guided DNase Cas9, the clustered regularly interspaced short palindromic repeats (CRISPR) system, has been developed. Here we report the efficient generation of an iPS cell model for immunodeficiency, centromeric region instability, facial anomalies syndrome (ICF) syndrome using the CRISPR system. We obtained iPS cells with mutations in both alleles of DNA methyltransferase 3B (DNMT3B) in 63% of transfected clones. Our data suggest that the CRISPR system is highly efficient and useful for genome engineering of human iPS cells.
Gravity and embryonic development
NASA Technical Reports Server (NTRS)
Young, R. S.
1976-01-01
The relationship between the developing embryo (both plant and animal) and a gravitational field has long been contemplated. The difficulty in designing critical experiments on the surface of the earth because of its background of 1 g, has been an obstacle to a resolution of the problem. Biological responses to gravity (particularly in plants) are obvious in many cases; however, the influence of gravity as an environmental input to the developing embryo is not as obvious and has proven to be extremely difficult to define. In spite of this, over the years numerous attempts have been made using a variety of embryonic materials to come to grips with the role of gravity in development. Three research tools are available: the centrifuge, the clinostat, and the orbiting spacecraft. Experimental results are now available from all three sources. Some tenuous conclusions are drawn, and an attempt at a unifying theory of gravitational influence on embryonic development is made.
The use of bioimpedance analysis to evaluate lymphedema.
Warren, Anne G; Janz, Brian A; Slavin, Sumner A; Borud, Loren J
2007-05-01
Lymphedema, a chronic disfiguring condition resulting from lymphatic dysfunction or disruption, can be difficult to accurately diagnose and manage. Of particular challenge is identifying the presence of clinically significant limb swelling through simple and noninvasive methods. Many historical and currently used techniques for documenting differences in limb volume, including volume displacement and circumferential measurements, have proven difficult and unreliable. Bioimpedance spectroscopy analysis, a technology that uses resistance to electrical current in comparing the composition of fluid compartments within the body, has been considered as a cost-effective and reproducible alternative for evaluating patients with suspected lymphedema. All patients were recruited through the Beth Israel Deaconess Medical Center Lymphedema Clinic. A total of 15 patients (mean age: 55.2 years) with upper-extremity or lower-extremity lymphedema as documented by lymphoscintigraphy underwent bioimpedance spectroscopy analysis using an Impedimed SFB7 device. Seven healthy medical students and surgical residents (mean age: 26.9 years) were selected to serve as normal controls. All study participants underwent analysis of both limbs, which allowed participants to act as their own controls. The multifrequency bioimpedance device documented impedance values for each limb, with lower values correlating with higher levels of accumulated protein-rich edematous fluid. The average ratio of impedance to current flow of the affected limb to the unaffected limb in lymphedema patients was 0.9 (range: 0.67 to 1.01). In the control group, the average impedance ratio of the participant's dominant limb to their nondominant limb was 0.99 (range: 0.95 to 1.02) (P = 0.01). Bioimpedance spectroscopy can be used as a reliable and accurate tool for documenting the presence of lymphedema in patients with either upper- or lower-extremity swelling. Measurement with the device is quick and simple and results are reproducible among patients. Given significant limitations with other methods of evaluating lymphedema, the use of bioimpedance analysis may aid in the diagnosis of lymphedema and allow for tracking patients over time as they proceed with treatment of their disease.
Aziz, Michael
2015-01-01
Recent technological advances have made airway management safer. Because difficult intubation remains challenging to predict, having tools readily available that can be used to manage a difficult airway in any setting is critical. Fortunately, video technology has resulted in improvements for intubation performance while using laryngoscopy by various means. These technologies have been applied to rigid optical stylets, flexible intubation scopes, and, most notably, rigid laryngoscopes. These tools have proven effective for the anticipated difficult airway as well as the unanticipated difficult airway.
Data Provenance Hybridization Supporting Extreme-Scale Scientific WorkflowApplications
DOE Office of Scientific and Technical Information (OSTI.GOV)
Elsethagen, Todd O.; Stephan, Eric G.; Raju, Bibi
As high performance computing (HPC) infrastructures continue to grow in capability and complexity, so do the applications that they serve. HPC and distributed-area computing (DAC) (e.g. grid and cloud) users are looking increasingly toward workflow solutions to orchestrate their complex application coupling, pre- and post-processing needs To gain insight and a more quantitative understanding of a workflow’s performance our method includes not only the capture of traditional provenance information, but also the capture and integration of system environment metrics helping to give context and explanation for a workflow’s execution. In this paper, we describe IPPD’s provenance management solution (ProvEn) andmore » its hybrid data store combining both of these data provenance perspectives.« less
Provenance testing at Michigan Technological University
Robert L. Sajdak
1970-01-01
The location of M.T.U. in the Keweenaw Peninsula of Upper Michigan provides some unique advantages and disadvantages in provenance testing and tree improvement research. Extremes in summer and winter temperatures are uncommon because of the moderating effect of Lake Superior. Near the Lake we have about 140 frost-free days while inland the frost-free season is only 80...
Extremes in Oxidizing Power, Acidity, and Basicity
2013-10-01
and extremely difficult to oxidize, with reversible redox potentials calculated up to 5 V above ferrocene /ferricenium. In liquid sulfur dioxide, the...ol, the undecafluorinated anion is oxidized reversibly at 2.43 V above ferrocene /ferricenium (calculated 2.40 V) but the radical is too unstable for...unusually weakly nucleophilic and extremely difficult to oxidize, with reversible redox potentials calculated up to 5 V above ferrocene /ferricenium. In
Automated Generation of Technical Documentation and Provenance for Reproducible Research
NASA Astrophysics Data System (ADS)
Jolly, B.; Medyckyj-Scott, D.; Spiekermann, R.; Ausseil, A. G.
2017-12-01
Data provenance and detailed technical documentation are essential components of high-quality reproducible research, however are often only partially addressed during a research project. Recording and maintaining this information during the course of a project can be a difficult task to get right as it is a time consuming and often boring process for the researchers involved. As a result, provenance records and technical documentation provided alongside research results can be incomplete or may not be completely consistent with the actual processes followed. While providing access to the data and code used by the original researchers goes some way toward enabling reproducibility, this does not count as, or replace, data provenance. Additionally, this can be a poor substitute for good technical documentation and is often more difficult for a third-party to understand - particularly if they do not understand the programming language(s) used. We present and discuss a tool built from the ground up for the production of well-documented and reproducible spatial datasets that are created by applying a series of classification rules to a number of input layers. The internal model of the classification rules required by the tool to process the input data is exploited to also produce technical documentation and provenance records with minimal additional user input. Available provenance records that accompany input datasets are incorporated into those that describe the current process. As a result, each time a new iteration of the analysis is performed the documentation and provenance records are re-generated to provide an accurate description of the exact process followed. The generic nature of this tool, and the lessons learned during its creation, have wider application to other fields where the production of derivative datasets must be done in an open, defensible, and reproducible way.
ERIC Educational Resources Information Center
Batey, Mark
2012-01-01
The scientific study of creativity has proven a difficult undertaking. Researchers have employed a diversity of definitions and measurement methods. As a result, creativity research is underrepresented in the literature and the findings of different studies often prove difficult to draw into a coherent body of understanding. A heuristic framework…
Final Report for DE-FG02-93ER14376,Ionic Transport in Electrochemical Media
DOE Office of Scientific and Technical Information (OSTI.GOV)
J. W. Halley
This project was a molecular dynamics study of the relevant issues associated with the structure and transport of lithium in polymer electrolytes such as polyethylene oxide(PEO). In close collaboration with quantum chemist Larry Curtiss and neutron scatterers David Lee Price and Marie-Louise Saboungi at Argonne, we used molecular dynamics to study the local structure and dynamics and ion transport in the polymer. The studies elucidated the mechanism of Li transport in PEO, revealing that the rate limiting step is extremely sensitive to the magnitude of the torsion forces in the backbone of the polymer. Because the torsion forces are difficultmore » to manipulate chemically, this makes it easier to understand why improving the conductivity of PEO based electrolytes has proven to be very difficult. We studied the transport properties of cations in ionic liquids as possible additives to polymer membranes for batteries and fuel cells and found preliminary indications that the transport is enhanced near phase separation in acid-ionic liquid mixtures.« less
How can Doctors Improve their Communication Skills?
Kumari, Archana; Chakrawarty, Avinash
2015-01-01
The process of curing a patient requires a holistic approach which involves considerations beyond treating a disease. It warrants several skills in a doctor along with technical expertise. Studies have shown that good communication skill in a doctor improve patient’s compliance and overall satisfaction. There are certain basic principles of practicing good communication. Patient listening, empathy, and paying attention to the paraverbal and non verbal components of the communication are the important ones that are frequently neglected. Proper information about the nature, course and prognosis of the disease is important. Besides, patients and attendants should always be explained about the necessity and yield of expensive investigations and risks/benefits involved in invasive procedures. One should be extremely cautious while managing difficult encounters and breaking bad news. Formal training of the doctors in improving communication skills is necessary and has proven to improve overall outcome. The authors recommend inclusion of formal training in communication skills in medical curriculum and training of practising doctors in the form of CMEs and CPEs. PMID:25954636
NASA Astrophysics Data System (ADS)
Rabemananajara, Tanjona R.; Horowitz, W. A.
2017-09-01
To make predictions for the particle physics processes, one has to compute the cross section of the specific process as this is what one can measure in a modern collider experiment such as the Large Hadron Collider (LHC) at CERN. Theoretically, it has been proven to be extremely difficult to compute scattering amplitudes using conventional methods of Feynman. Calculations with Feynman diagrams are realizations of a perturbative expansion and when doing calculations one has to set up all topologically different diagrams, for a given process up to a given order of coupling in the theory. This quickly makes the calculation of scattering amplitudes a hot mess. Fortunately, one can simplify calculations by considering the helicity amplitude for the Maximally Helicity Violating (MHV). This can be extended to the formalism of on-shell recursion, which is able to derive, in a much simpler way the expression of a high order scattering amplitude from lower orders.
A theoretical study of the effect of a non-aqueous proton donor on electrochemical ammonia synthesis
Zhang, Linan; Mallikarjun Sharada, Shaama; Singh, Aayush R.; ...
2018-01-17
We report that ammonia synthesis is one of the most studied reactions in heterogeneous catalysis. To date, however, electrochemical N 2 reduction in aqueous systems has proven to be extremely difficult, mainly due to the competing hydrogen evolution reaction (HER). Recently, it has been shown that transition metal complexes based on molybdenum can reduce N 2 to ammonia at room temperature and ambient pressure in a non-aqueous system, with a relatively small amount of hydrogen output. We demonstrate that the non-aqueous proton donor they have chosen, 2,6-lutidinium (LutH +), is a viable substitute for hydronium in the electrochemical process atmore » a solid surface, since this donor can suppress the HER rate. Finally, we also show that the presence of LutH + can selectively stabilize the *NNH intermediate relative to *NH or *NH 2via the formation of hydrogen bonds, indicating that the use of non-aqueous solvents can break the scaling relationship between limiting potential and binding energies.« less
Overview and Status of Experimental Neutrino Physics
NASA Astrophysics Data System (ADS)
Stancu, Ion
2002-10-01
Seventy years after the existence of the neutrino has been postulated by Wolfgang Pauli, these elusive particles remain surrounded by mystery. One of the most fundamental questions about neutrinos is whether they have an identically vanishing mass, as assumed by the Standard Model, or not. Direct measurements have proven to be extremely difficult to perform, and have yielded so far only upper limits. However, if neutrino flavour oscillations do happen, this would automatically imply that at least one of the three neutrinos (the electron, muon or tau neutrino) must have a non-zero mass. The present experimental data indicate that both the solar and atmospheric neutrino deficits can be explained by the phenomenon of neutrino oscillations, while the positive signal reported by the accelerator-based LSND experiment remains to be verified by an independent measurement (MiniBooNE). This talk reviews the current status of the neutrino oscillations experiments, experiments which are quite likely to produce results with significant consequences for both the Standard Model and Cosmology.
Satellite borne gravity gradiometer study
NASA Technical Reports Server (NTRS)
Metzger, E.; Jircitano, A.; Affleck, C.
1976-01-01
Gravity gradiometry is recognized to be a very difficult instrumentation problem because extremely small differential acceleration levels have to be measured, 0.1 EU corresponds to an acceleration of 10 to the minus 11th power g at two points 1 meter apart. A feasibility model of a gravity gradiometer is being developed for airborne applications using four modified versions of the proven Model VII accelerometers mounted on a slowly rotating fixture. Gravity gradients are being measured to 1.07 EU in a vertical rotation axis orientation. Equally significant are the outstanding operational characteristics such as fast reaction time, low temperature coefficients and high degree of bias stability over long periods of time. The rotating accelerometer gravity gradiometer approach and its present status is discussed and it is the foundation for the orbital gravity gradiometer analyzed. The performance levels achieved in a 1 g environment of the earth and under relatively high seismic disturbances, lend the orbital gravity gradiometer a high confidence level of success.
A theoretical study of the effect of a non-aqueous proton donor on electrochemical ammonia synthesis
DOE Office of Scientific and Technical Information (OSTI.GOV)
Zhang, Linan; Mallikarjun Sharada, Shaama; Singh, Aayush R.
We report that ammonia synthesis is one of the most studied reactions in heterogeneous catalysis. To date, however, electrochemical N 2 reduction in aqueous systems has proven to be extremely difficult, mainly due to the competing hydrogen evolution reaction (HER). Recently, it has been shown that transition metal complexes based on molybdenum can reduce N 2 to ammonia at room temperature and ambient pressure in a non-aqueous system, with a relatively small amount of hydrogen output. We demonstrate that the non-aqueous proton donor they have chosen, 2,6-lutidinium (LutH +), is a viable substitute for hydronium in the electrochemical process atmore » a solid surface, since this donor can suppress the HER rate. Finally, we also show that the presence of LutH + can selectively stabilize the *NNH intermediate relative to *NH or *NH 2via the formation of hydrogen bonds, indicating that the use of non-aqueous solvents can break the scaling relationship between limiting potential and binding energies.« less
Primary care in Ontario, Canada: New proposals after 15 years of reform.
Marchildon, Gregory P; Hutchison, Brian
2016-07-01
Primary care has proven to be extremely difficult to reform in Canada because of the original social compact between the state and physicians that led to the introduction of universal medical care insurance in the 1960s. However, in the past decade, the provincial government of Ontario has led the way in Canada in funding a suite of primary care practice models, some of which differ substantially from traditional solo and group physician practices based on fee-for-service payment. Independent evaluations show some positive improvements in patient care. Nonetheless, the Ontario government's large investment in the reform combined with high expectations concerning improved performance and the deteriorating fiscal position of the province's finances have led to major conflict with organized medicine over physician budgets and the government's consideration of an even more radical restructuring of the system of primary care in the province. Copyright © 2016 The Author(s). Published by Elsevier Ireland Ltd.. All rights reserved.
Simultaneous ASCA and EUVE Observations of Capella
NASA Astrophysics Data System (ADS)
Brickhouse, N. S.; Dupree, A. K.; Edgar, R. J.; Drake, S. A.; White, N. E.; Liedahl, D. A.; Singh, K. P.
1997-05-01
We present simultaneous observations taken in Mar 1996 of the bright stellar coronal source Capella (HD 34029) with the ASCA and EUVE satellites. Previous EUVE observations of Fe emission lines (Fe VIII --- XXIV, excluding XVII) revealed a narrow emission measure feature at 6 x 10(6) K, which has proven to be remarkably stable over several years (flux from Fe XVIII and XIX has not varied by more than 30%), while lines formed at higher temperatures have shown intensity variations up to factors of 4. Furthermore, extremely high signal-to-noise spectra obtained by summing all EUVE measurements show that the Fe/H abundance ratio is consistent with solar photospheric. (See Dupree et al. 1993, ApJ, 418, L41; Brickhouse, Raymond, & Smith 1995, ApJSupp, 97, 551; Brickhouse 1996, IAU Coll. 152, Astrophysics in the Extreme Ultraviolet, Bowyer & Malina, eds (Kluwer), 141.) Meanwhile, the ASCA data of Capella have proven notoriously difficult to analyze. The performance verification (PV) phase data suggested a somewhat subsolar Fe abundance, but models were in poor agreement with the data (chi (2red) ~ 6). (See Drake 1996, Conf. on Cosmic Abundances, U. Maryland). Since the emission lines observed by EUVE are formed at the same emitting temperatures as the X-ray spectrum (Capella is ``soft'' such that very little flux is observed above 2 keV), the emission measure distribution derived from EUVE lines should provide a direct prediction of the X-ray spectrum, with only the relative abundances of species other than Fe as free parameters. Like the PV data, the new ASCA spectrum is not well fit by any of the standard models. Applying the constraints imposed by EUVE does not make a major improvement in the fit --- multi-thermal, variable abundance models such as Raymond-Smith and MEKAL do not provide any acceptable fit (chi (2red) > 5). We discuss our efforts to understand the X-ray spectrum, including studies of the uncertainties in the atomic data and of the underlying assumptions of the source models.
Data provenance assurance in the cloud using blockchain
NASA Astrophysics Data System (ADS)
Shetty, Sachin; Red, Val; Kamhoua, Charles; Kwiat, Kevin; Njilla, Laurent
2017-05-01
Ever increasing adoption of cloud technology scales up the activities like creation, exchange, and alteration of cloud data objects, which create challenges to track malicious activities and security violations. Addressing this issue requires implementation of data provenance framework so that each data object in the federated cloud environment can be tracked and recorded but cannot be modified. The blockchain technology gives a promising decentralized platform to build tamper-proof systems. Its incorruptible distributed ledger/blockchain complements the need of maintaining cloud data provenance. In this paper, we present a cloud based data provenance framework using block chain which traces data record operations and generates provenance data. We anchor provenance data records into block chain transactions, which provide validation on provenance data and preserve user privacy at the same time. Once the provenance data is uploaded to the global block chain network, it is extremely challenging to tamper the provenance data. Besides, the provenance data uses hashed user identifiers prior to uploading so the blockchain nodes cannot link the operations to a particular user. The framework ensures that the privacy is preserved. We implemented the architecture on ownCloud, uploaded records to blockchain network, stored records in a provenance database and developed a prototype in form of a web service.
How to Handle Difficult Parents: Proven Solutions for Teachers. Second Edition
ERIC Educational Resources Information Center
Tingley, Suzanne Capek
2012-01-01
"How to Handle Difficult Parents" is a funny, but practical, guide to working effectively with parents and avoiding unnecessary conflict. Whether you're a teacher (regular or special education) or a coach, this book will give you practical suggestions regarding what to say and how to say it to parents who question your lesson plans, challenge your…
A review of electron-nucleus bremsstrahlung cross sections between 1 and 10 MeV
NASA Astrophysics Data System (ADS)
Mangiarotti, A.; Martins, M. N.
2017-12-01
More than 80 years have passed since the first calculations of electron-nucleus bremsstrahlung cross sections were published by Sommerfeld, for non-relativistic electrons, and, independently, by Sauter, Bethe and Heitler, and Racah, for relativistic electrons. The Bethe-Heitler expression, that is based on the first Born approximation and includes the screening of the Coulomb field of the nucleus by the atomic electrons, has proven to work well at moderately high energies where the Landau-Pomeranchuk-Migdal effect is negligible. We review the current theoretical and experimental status with a highlight on electrons with kinetic energies between 1 and 10 MeV. The choice is motivated by the peculiar difficulties present in this energy region, where it is necessary to treat simultaneously the interaction with the Coulomb field beyond the first Born approximation and the effect of screening. A fully numerical approach within the S-matrix formalism has proven to be extremely difficult above a few MeV, because the number of partial waves needed for an accurate evaluation is prohibitively large. Here we focus on analytic results, including the more complex ones employing the Furry-Sommerfeld-Maue wave functions and taking into account the next-to-leading order, and discuss the advantages and limitations in light of the best available data. The influence of multiple scattering in the target is investigated under the actual experimental conditions. A comparison with the widely used cross section tabulations by Seltzer and Berger is also presented.
ERIC Educational Resources Information Center
Forehand, Rex; Long, Nicholas
Parenting is one the most difficult tasks that adults face, and parenting strong-willed children can be even more difficult and frustrating. Parents of strong-willed children are often frustrated by their children's behavior as well as the lack of support and resources to help them deal with their children. This book describes a self-guided…
Adenomyosis: Difficult to Diagnose, and Difficult to Treat
2001-01-01
Drug therapy may be effective in controlling symptoms but the frequent coexistence of endometriosis and the lack of controlled studies make their efficacy difficult to quantify. Danazol IUD has been shown to reduce symptoms. Conservative surgery involving endomyometrial ablation, laparoscopic myometrial electrocoagulation or excision has proven to be effective in more than 50% of patients, although follow up has been restricted to three years. Arterial uterine artery embolization is a new technique which may be tried before considering hysterectomy. Hysterectomy may still be necessary in severe cases of adenomyosis. PMID:18493552
A Scientific Data Provenance Harvester for Distributed Applications
DOE Office of Scientific and Technical Information (OSTI.GOV)
Stephan, Eric G.; Raju, Bibi; Elsethagen, Todd O.
Data provenance provides a way for scientists to observe how experimental data originates, conveys process history, and explains influential factors such as experimental rationale and associated environmental factors from system metrics measured at runtime. The US Department of Energy Office of Science Integrated end-to-end Performance Prediction and Diagnosis for Extreme Scientific Workflows (IPPD) project has developed a provenance harvester that is capable of collecting observations from file based evidence typically produced by distributed applications. To achieve this, file based evidence is extracted and transformed into an intermediate data format inspired in part by W3C CSV on the Web recommendations, calledmore » the Harvester Provenance Application Interface (HAPI) syntax. This syntax provides a general means to pre-stage provenance into messages that are both human readable and capable of being written to a provenance store, Provenance Environment (ProvEn). HAPI is being applied to harvest provenance from climate ensemble runs for Accelerated Climate Modeling for Energy (ACME) project funded under the U.S. Department of Energy’s Office of Biological and Environmental Research (BER) Earth System Modeling (ESM) program. ACME informally provides provenance in a native form through configuration files, directory structures, and log files that contain success/failure indicators, code traces, and performance measurements. Because of its generic format, HAPI is also being applied to harvest tabular job management provenance from Belle II DIRAC scheduler relational database tables as well as other scientific applications that log provenance related information.« less
Refining a methodology for determining the economic impacts of transportation improvements.
DOT National Transportation Integrated Search
2012-07-01
Estimating the economic impact of transportation improvements has previously proven to be a difficult task. After an exhaustive literature review, it was clear that the transportation profession lacked standards and methodologies for determining econ...
Wetlands Restoration Definitions and Distinctions
Ecological restoration is a valuable endeavor that has proven very difficult to define. The term indicates that degraded and destroyed natural wetland systems will be reestablished to sites where they once existed. But, what wetland ecosystems are we talki
Atypical Rocky Mountain spotted fever with polyarticular arthritis.
Chaudhry, Muhammad A; Scofield, Robert Hal
2013-11-01
Rocky Mountain spotted fever (RMSF) is an acute, serious tick borne illness caused by Rickettsia rickettsi. Frequently, RMSF is manifested by headache, a typical rash and fever but atypical disease is common, making diagnosis difficult. Inflammatory arthritis as a manifestation is rare. The purpose of this study is to describe a patient with serologically proven RMSF who presented in an atypical manner with inflammatory arthritis of the small joints of the hands and to review the previously reported patients with rickettsial infection and inflammatory arthritis. An 18-year-old woman presented with a rash that began on the distal extremities and spread centrally, along with hand pain and swelling. She had tenderness and swelling of the metacarpophlangeal joints on examination in addition to an erythematosus macular rash and occasional fever. Acute and convalescent serology demonstrated R rickettsi infection. She was successfully treated with doxycycline. Inflammatory arthritis is a rare manifestation of RMSF or other rickettsial infection with 8 previously reported patients, only 1 of whom had RMSF. Physician must have a high index of suspicion for RMSF because of atypical presentations.
Atypical Rocky Mountain spotted fever with polyarticular arthritis
Chaudhry, Muhammad A.; Hal Scofield, R.
2017-01-01
Background Rocky Mountain Spotted Fever (RMSF) is an acute, serious tick borne illness caused by Rickettsia rickettsi. Frequently RMSF is manifested by headache, a typical rash and fever but atypical disease is common, making diagnosis difficult. Inflammatory arthritis as a manifestation is rare Purpose Describe a patient with serologically proven RMSF who presented in an atypical manner with inflammatory arthritis of the small joints of the hands, and to review the previously reported patients with rickettsial infection and inflammatory arthritis Patient An 18 year old woman presented with a rash that began on the distal extremities and spread centrally, along with hand pain and swelling. She had tenderness and swelling of the metacarpophlangeal joints on exam as well as an erythematosus macular rash, and occasional fever. Acute and convalescent serology demonstrated Rickettsia rickettsi infection. She was successfully treated with doxycycline. Conclusion Inflammatory arthritis is a rare manifestation of RMSF or other rickettsial infection with eight previously reported patients, only one of whom had RMSF. Physician must have a high index of suspicion for RMSF because of atypical presentations. PMID:24157965
Genetic, genomic, and molecular tools for studying the protoploid yeast, L. waltii.
Di Rienzi, Sara C; Lindstrom, Kimberly C; Lancaster, Ragina; Rolczynski, Lisa; Raghuraman, M K; Brewer, Bonita J
2011-02-01
Sequencing of the yeast Kluyveromyces waltii (recently renamed Lachancea waltii) provided evidence of a whole genome duplication event in the lineage leading to the well-studied Saccharomyces cerevisiae. While comparative genomic analyses of these yeasts have proven to be extremely instructive in modeling the loss or maintenance of gene duplicates, experimental tests of the ramifications following such genome alterations remain difficult. To transform L. waltii from an organism of the computational comparative genomic literature into an organism of the functional comparative genomic literature, we have developed genetic, molecular and genomic tools for working with L. waltii. In particular, we have characterized basic properties of L. waltii (growth, ploidy, molecular karyotype, mating type and the sexual cycle), developed transformation, cell cycle arrest and synchronization protocols, and have created centromeric and non-centromeric vectors as well as a genome browser for L. waltii. We hope that these tools will be used by the community to follow up on the ideas generated by sequence data and lead to a greater understanding of eukaryotic biology and genome evolution. 2010 John Wiley & Sons, Ltd.
Genetic, genomic, and molecular tools for studying the protoploid yeast, L. waltii
Di Rienzi, Sara C.; Lindstrom, Kimberly C.; Lancaster, Ragina; Rolczynski, Lisa; Raghuraman, M. K.; Brewer, Bonita J.
2011-01-01
Sequencing of the yeast Kluyveromyces waltii (recently renamed Lachancea waltii) provided evidence of a whole genome duplication event in the lineage leading to the well-studied Saccharomyces cerevisiae. While comparative genomic analyses of these yeasts have proven to be extremely instructive in modeling the loss or maintenance of gene duplicates, experimental tests of the ramifications following such genome alterations remain difficult. To transform L. waltii from an organism of the computational comparative genomic literature into an organism of the functional comparative genomic literature, we have developed genetic, molecular and genomic tools for working with L. waltii. In particular, we have characterized basic properties of L. waltii (growth, ploidy, molecular karyotype, mating type and the sexual cycle), developed transformation, cell cycle arrest and synchronization protocols, and have created centromeric and non-centromeric vectors as well as a genome browser for L. waltii. We hope that these tools will be used by the community to follow up on the ideas generated by sequence data and lead to a greater understanding of eukaryotic biology and genome evolution. PMID:21246627
Long range guided wave defect monitoring in rail track
NASA Astrophysics Data System (ADS)
Loveday, Philip W.; Long, Craig S.
2014-02-01
A guided wave ultrasound system was previously developed for monitoring rail track used on heavy duty freight lines. This system operates by transmitting guided waves between permanently installed transmit and receive transducers spaced approximately 1km apart. The system has been proven to reliably detect rail breaks without false alarms. While cracks are sometimes detected there is a trade - off between detecting cracks and the possibility of false alarms. Adding a pulse-echo mode of operation to the system could provide increased functionality by detecting, locating and possibly monitoring cracks. This would require an array of transducers to control the direction and mode of propagation and it would be necessary to detect cracks up to a range of approximately 500 m in either direction along the rail. A four transducer array was designed and full matrix capture was used for field measurements. Post processing of the signals showed that a thermite weld could be detected at a range of 790m from the transducer array. It was concluded that the required range can be achieved in new rail while it would be extremely difficult in very old rail.
NASA Technical Reports Server (NTRS)
Hunt, A. J.; Ayers, M. R.; Sibille, L.; Smith, D. D.
2001-01-01
The transition from sol to gel is a process that is critical to the properties of engineered nanomaterials, but one with few available techniques for observing the dynamic processes occurring during the evolution of the gel network. Specifically, the observation of various cluster aggregation models, such as diffusion-limited and reaction-limited cluster growth can be quite difficult. This can be rather important as the actual aggregation model can dramatically influence the mechanical properties of gels, and is significantly affected by the presence of convective flows, or their absence in microgravity. We have developed two new non-intrusive optical methods for observing the aggregation processes within gels in real time. These make use of the dynamic behavior of laser speckle patterns produced when an intense laser source is passed through a gelling sol. The first method is a simplified time-correlation measurement, where the speckle pattern is observed using a CCD camera and information on the movement of the scattering objects is readily apparent. This approach is extremely sensitive to minute variations in the flow field as the observed speckle pattern is a diffraction-based image, and is therefore sensitive to motions within the sol on the order of the wavelength of the probing light. Additionally, this method has proven useful in determining a precise time for the gel-point, an event often difficult to measure. Monitoring the evolution of contrast within the speckle field is another method that has proven useful for studying aeration. In this case, speckle contrast is dependent upon the size (correlation length) and number of scattering centers, increasing with increasing size, and decreasing with increasing numbers. The dynamic behavior of cluster growth in gels causes both of these to change simultaneously with time, the exact rate of which is determined by the specific aggregation model involved. Actual growth processes can now be observed, and the effects of varying gravity fields on the growth processes qualitatively described. Results on preliminary ground-based measurements have been obtained.
A Scientific Data Provenance API for Distributed Applications
DOE Office of Scientific and Technical Information (OSTI.GOV)
Raju, Bibi; Elsethagen, Todd O.; Stephan, Eric G.
Data provenance has been an active area of research as a means to standardize how the origin of data, process event history, and what or who was responsible for influencing results is explained. There are two approaches to capture provenance information. The first approach is to collect observed evidence produced by an executing application using log files, event listeners, and temporary files that are used by the application or application developer. The provenance translated from these observations is an interpretation of the provided evidence. The second approach is called disclosed because the application provides a firsthand account of the provenancemore » based on the anticipated questions on data flow, process flow, and responsible agents. Most observed provenance collection systems collect lot of provenance information during an application run or workflow execution. The common trend in capturing provenance is to collect all possible information, then attempt to find relevant information, which is not efficient. Existing disclosed provenance system APIs do not work well in distributed environment and have trouble finding where to fit the individual pieces of provenance information. This work focuses on determining more reliable solutions for provenance capture. As part of the Integrated End-to-end Performance Prediction and Diagnosis for Extreme Scientific Workflows (IPPD) project, an API was developed, called Producer API (PAPI), which can disclose application targeted provenance, designed to work in distributed environments by means of unique object identification methods. The provenance disclosure approach used adds additional metadata to the provenance information to uniquely identify the pieces and connect them together. PAPI uses a common provenance model to support this provenance integration across disclosure sources. The API also provides the flexibility to let the user decide what to do with the collected provenance. The collected provenance can be sent to a triple store using REST services or it can be logged to a file.« less
Mack, Natasha; Ramirez, Catalina B; Friedland, Barbara; Nnko, Soori
2013-01-01
Achieving participant comprehension has proven to be one of the most difficult, practical, and ethical challenges of HIV prevention clinical trials. It becomes even more challenging when local languages do not have equivalent scientific and technical vocabularies, rendering communication of scientific concepts in translated documents extremely difficult. Even when bilingual lexicons are developed, there is no guarantee that participants understand the terminology as translated. We conducted twelve focus groups with women of reproductive age in Mwanza, Tanzania to explore the effectiveness of four questioning techniques for: (1) assessing participants' familiarity with existing technical terms and concepts, (2) generating a list of acceptable technical and non-technical terms, (3) testing our definitions of technical terms, and (4) verifying participants' preferences for terms. Focus groups were transcribed, translated, and qualitatively analyzed. A translation process that uses all four questioning techniques in a step-wise approach is an effective way to establish a baseline understanding of participants' familiarity with research terms, to develop and test translatable definitions, and to identify participants' preferred terminology for international HIV clinical research. This may help to ensure that important concepts are not "lost in translation." The results emphasize the importance of using a variety of techniques depending on the level of participant familiarity with research concepts, the existence of colloquial or technical terms in the target language, and the inherent complexity of the terms.
Mack, Natasha; Ramirez, Catalina B.; Friedland, Barbara; Nnko, Soori
2013-01-01
Introduction Achieving participant comprehension has proven to be one of the most difficult, practical, and ethical challenges of HIV prevention clinical trials. It becomes even more challenging when local languages do not have equivalent scientific and technical vocabularies, rendering communication of scientific concepts in translated documents extremely difficult. Even when bilingual lexicons are developed, there is no guarantee that participants understand the terminology as translated. Methods We conducted twelve focus groups with women of reproductive age in Mwanza, Tanzania to explore the effectiveness of four questioning techniques for: (1) assessing participants' familiarity with existing technical terms and concepts, (2) generating a list of acceptable technical and non-technical terms, (3) testing our definitions of technical terms, and (4) verifying participants' preferences for terms. Focus groups were transcribed, translated, and qualitatively analyzed. Results and Discussion A translation process that uses all four questioning techniques in a step-wise approach is an effective way to establish a baseline understanding of participants' familiarity with research terms, to develop and test translatable definitions, and to identify participants' preferred terminology for international HIV clinical research. This may help to ensure that important concepts are not “lost in translation.” The results emphasize the importance of using a variety of techniques depending on the level of participant familiarity with research concepts, the existence of colloquial or technical terms in the target language, and the inherent complexity of the terms. PMID:24040075
Osmium Isotope and Highly Siderophile Element Compositions of Lunar Orange and Green Glasses
NASA Technical Reports Server (NTRS)
Walker, R. J.; Horan, M. F.; Shearer, C. K.; Papike, J. J.
2003-01-01
The absolute and relative abundances of the highly siderophile elements (HSE) present in planetary mantles are primarily controlled by: 1) silicate-metal partitioning during core-mantle differentiation, 2) the subsequent addition of HSE to mantles via continued planetary accretion. Consequently, constraints on the absolute and relative abundances of the HSE in the lunar mantle will provide unique insights to the formation and late accretionary history of not only the Moon, but also Earth. Determining the HSE content of the lunar mantle, however, has proven difficult, because no bona fide mantle rocks have been collected from the moon. The only materials presently available for constraining mantle abundances are lunar volcanic rocks. Lunar basalts typically have very low concentrations of HSE and highly fractionated HSE patterns. Because of our extremely limited understanding of mantle melt partitioning of the HSE, even for terrestrial systems, extrapolations to mantle compositions from basaltic compositions are difficult, except possibly for the less compatible HSE Pt and Pd. Primitive, presumably less fractionated materials, such as picritic glasses are potentially more diagnostic of the lunar interior. Here we report Os isotopic composition data and Re, Os, Ir, Ru, Pt and Pd concentration data for green glass (15426,164) and orange glass (74001,1217). As with previous studies utilizing neutron activation analysis, we are examining different size fractions of the spherules to assess the role of surface condensation in the generation of the HSE abundances.
Emerging communications technologies for outer-planet exploration
NASA Technical Reports Server (NTRS)
Stelzried, C.; Lesh, J.
2001-01-01
Communication over long free space distances is extremely difficult due to the inverse squared propagation losses associated with link distance. That makes communications particularly difficult from outer planet destinations.
DOE Office of Scientific and Technical Information (OSTI.GOV)
Schissel, David; Greenwald, Martin
The MPO (Metadata, Provenance, Ontology) Project successfully addressed the goal of improving the usefulness and traceability of scientific data by building a system that could capture and display all steps in the process of creating, analyzing and disseminating that data. Throughout history, scientists have generated handwritten logbooks to keep track of data, their hypotheses, assumptions, experimental setup, and computational processes as well as reflections on observations and issues encountered. Over the last several decades, with the growth of personal computers, handheld devices, and the World Wide Web, the handwritten logbook has begun to be replaced by electronic logbooks. This transitionmore » has brought increased capability such as supporting multi-media, hypertext, and fast searching. However, content creation and metadata (a set of data that describes and gives information about other data) capturing has for the most part remained a manual activity just as it was with handwritten logbooks. This has led to a fragmentation of data, processing, and annotation that has only accelerated as scientific workflows continue to increase in complexity. From a scientific perspective, it is very important to be able to understand the lineage of any piece of data: who, what, when, how, and why. This is typically referred to as data provenance. The fragmentation discussed previously often means that data provenance is lost. As scientific workflows move to powerful computers and become more complex, the ability to track all of the steps involved in creating a piece of data become even more difficult. It was the goal of the MPO (Metadata, Provenance, Ontology) Project to create a system (the MPO System) that allows for automatic provenance and metadata capturing in such a way to allow easy searching and browsing. This goal needed to be accomplished in a general way so that it may be used across a broad range of scientific domains, yet allow the addition of vocabulary (Ontology) that is domain specific as is required for intelligent searching and browsing in the scientific context. Through the creation and deployment of the MPO system, the goals of the project were achieved. An enhanced metadata, provenance, and ontology storage system was created. This was combined with innovative methodologies for navigating and exploring these data using a web browser for both experimental and simulation-based scientific research. In addition, a system to allow scientists to instrument their existing workflows for automatic metadata and provenance is part of the MPO system. In that way, a scientist can continue to use their existing methodology yet easily document their work. Workflows and data provenance can be displayed either graphically or in an electronic notebook format and support advanced search features including via ontology. The MPO system was successfully used in both Climate and Magnetic Fusion Energy Research. The software for the MPO system is located at https://github.com/MPO-Group/MPO and is open source distributed under the Revised BSD License. A demonstration site of the MPO system is open to the public and is available at https://mpo.psfc.mit.edu/. A Docker container release of the command line client is available for public download using the command docker pull jcwright/mpo-cli at https://hub.docker.com/r/jcwright/mpo-cli.« less
A Fiducial Approach to Extremes and Multiple Comparisons
ERIC Educational Resources Information Center
Wandler, Damian V.
2010-01-01
Generalized fiducial inference is a powerful tool for many difficult problems. Based on an extension of R. A. Fisher's work, we used generalized fiducial inference for two extreme value problems and a multiple comparison procedure. The first extreme value problem is dealing with the generalized Pareto distribution. The generalized Pareto…
Resurrecting Letters of Marque and Reprisal to Address Modern Threats
2013-03-01
history 4 and economics. Unfortunately, bringing maritime pirates and cyber criminals to justice has proven difficult under current norms of... cyber criminals have cost companies and consumers hundreds of millions of dollars and valuable intellectual property.79 The National Security Strategy
Sideband-Separating, Millimeter-Wave Heterodyne Receiver
NASA Technical Reports Server (NTRS)
Ward, John S.; Bumble, Bruce; Lee, Karen A.; Kawamura, Jonathan H.; Chattopadhyay, Goutam; Stek, paul; Stek, Paul
2010-01-01
Researchers have demonstrated a submillimeter-wave spectrometer that combines extremely broad bandwidth with extremely high sensitivity and spectral resolution to enable future spacecraft to measure the composition of the Earth s troposphere in three dimensions many times per day at spatial resolutions as high as a few kilometers. Microwave limb sounding is a proven remote-sensing technique that measures thermal emission spectra from molecular gases along limb views of the Earth s atmosphere against a cold space background.
Salmonella species group B causing endocarditis of the prosthetic mitral valve.
Al-Sherbeeni, Nisreen M
2009-08-01
The Salmonella species is an extremely rare cause of infective endocarditis. This case report is for Salmonella spp. group B proven by positive multiple blood cultures, and positive intraoperative culture from the vegetation of the mitral valve prosthesis.
Applying the Karma Provenance tool to NASA's AMSR-E Data Production Stream
NASA Astrophysics Data System (ADS)
Ramachandran, R.; Conover, H.; Regner, K.; Movva, S.; Goodman, H. M.; Pale, B.; Purohit, P.; Sun, Y.
2010-12-01
Current procedures for capturing and disseminating provenance, or data product lineage, are limited in both what is captured and how it is disseminated to the science community. For example, the Advanced Microwave Scanning Radiometer for the Earth Observing System (AMSR-E) Science Investigator-led Processing System (SIPS) generates Level 2 and Level 3 data products for a variety of geophysical parameters. Data provenance and quality information for these data sets is either very general (e.g., user guides, a list of anomalous data receipt and processing conditions over the life of the missions) or difficult to access or interpret (e.g., quality flags embedded in the data, production history files not easily available to users). Karma is a provenance collection and representation tool designed and developed for data driven workflows such as the productions streams used to produce EOS standard products. Karma records uniform and usable provenance metadata independent of the processing system while minimizing both the modification burden on the processing system and the overall performance overhead. Karma collects both the process and data provenance. The process provenance contains information about the workflow execution and the associated algorithm invocations. The data provenance captures metadata about the derivation history of the data product, including algorithms used and input data sources transformed to generate it. As part of an ongoing NASA funded project, Karma is being integrated into the AMSR-E SIPS data production streams. Metadata gathered by the tool will be presented to the data consumers as provenance graphs, which are useful in validating the workflows and determining the quality of the data product. This presentation will discuss design and implementation issues faced while incorporating a provenance tool into a structured data production flow. Prototype results will also be presented in this talk.
Mild Developmental Hypothyroidism and Trace Fear Conditioning: Role of Gender and Shock Duration.
Rodent models of developmental thyroid hormone (TH) deficiency aptly reflect the deleterious effects of severe TH deficiencies on brain structure and function in humans. However, the impact of moderate TH insufficiencies on neurodevelopmental outcomes has proven more difficult to...
Semantic Information and the Syntax of Propositional Attitude Verbs
ERIC Educational Resources Information Center
White, Aaron S.; Hacquard, Valentine; Lidz, Jeffrey
2018-01-01
Propositional attitude verbs, such as "think" and "want," have long held interest for both theoretical linguists and language acquisitionists because their syntactic, semantic, and pragmatic properties display complex interactions that have proven difficult to fully capture from either perspective. This paper explores the…
College Basketball on the Line.
ERIC Educational Resources Information Center
Suggs, Welch
1999-01-01
The National Collegiate Athletic Association (NCAA) has convened a working group to address problems in recruiting, gambling, academic standards, and other corrupt practices in college basketball programs. Such problems are neither new nor unique to basketball, and changing college sports has proven to be difficult. Recommendations are anticipated…
Extremophiles in Household Water Heaters
NASA Astrophysics Data System (ADS)
Wilpiszeski, R.; House, C. H.
2016-12-01
A significant fraction of Earth's microbial diversity comes from species living in extreme environments, but natural extreme environments can be difficult to access. Manmade systems like household water heaters serve as an effective proxy for thermophilic environments that are otherwise difficult to sample directly. As such, we are investigating the biogeography, taxonomic distribution, and evolution of thermophiles growing in domestic water heaters. Citizen scientists collected hot tap water culture- and filter- samples from 101 homes across the United States. We recovered a single species of thermophilic heterotroph from culture samples inoculated from water heaters across the United States, Thermus scotoductus. Whole-genome sequencing was conducted to better understand the distribution and evolution of this single species. We have also sequenced hyper-variable regions of the 16S rRNA gene from whole-community filter samples to identify the broad diversity and distribution of microbial cells captured from each water heater. These results shed light on the processes that shape thermophilic populations and genomes at a spatial resolution that is difficult to access in naturally occurring extreme ecosystems.
Effects of temperature and drought manipulations on seedlings of Scots pine provenances.
Taeger, S; Sparks, T H; Menzel, A
2015-03-01
Rising temperatures and more frequent and severe climatic extremes as a consequence of climate change are expected to affect growth and distribution of tree species that are adapted to current local conditions. Species distribution models predict a considerable loss of habitats for Pinus sylvestris. These models do not consider possible intraspecific differences in response to drought and warming that could buffer those impacts. We tested 10 European provenances of P. sylvestris, from the southwestern to the central European part of the species distribution, for their response to warming and to drought using a factorial design. In this common-garden experiment the air surrounding plants was heated directly to prevent excessive soil heating, and drought manipulation, using a rain-out shelter, permitted almost natural radiation, including high light stress. Plant responses were assessed as changes in phenology, growth increment and biomass allocation. Seedlings of P. sylvestris revealed a plastic response to drought by increased taproot length and root-shoot ratios. Strongest phenotypic plasticity of root growth was found for southwestern provenances, indicating a specific drought adaptation at the cost of overall low growth of aboveground structures even under non-drought conditions. Warming had a minor effect on growth but advanced phenological development and had a contrasting effect on bud biomass and diameter increment, depending on water availability. The intraspecific variation of P. sylvestris provenances could buffer climate change impacts, although additional factors such as the adaptation to other climatic extremes have to be considered before assisted migration could become a management option. © 2014 German Botanical Society and The Royal Botanical Society of the Netherlands.
Attention, Task Difficulty, and ADHD
ERIC Educational Resources Information Center
Nigg, Joel T.
2005-01-01
Comments on analysis of attention tasks in Attention Deficit Hyperactivity Disorder (ADHD) provided by Wilding (2005)points out that whereas many regulatory functions, including alertness or arousal, appear to be impaired in ADHD, demonstrating basic attention deficits in selection or orienting functions in the disorder has proven difficult. Yet…
Studying the Elusive Experience in Pervasive Games
ERIC Educational Resources Information Center
Stenros, Jaakko; Waern, Annika; Montola, Markus
2012-01-01
Studying pervasive games is inherently difficult and different from studying computer or board games. This article builds upon the experiences of staging and studying several playful pervasive technology prototypes. It discusses the challenges and pitfalls of evaluating pervasive game prototypes and charts methods that have proven useful in…
Bayesian model selection applied to artificial neural networks used for water resources modeling
NASA Astrophysics Data System (ADS)
Kingston, Greer B.; Maier, Holger R.; Lambert, Martin F.
2008-04-01
Artificial neural networks (ANNs) have proven to be extremely valuable tools in the field of water resources engineering. However, one of the most difficult tasks in developing an ANN is determining the optimum level of complexity required to model a given problem, as there is no formal systematic model selection method. This paper presents a Bayesian model selection (BMS) method for ANNs that provides an objective approach for comparing models of varying complexity in order to select the most appropriate ANN structure. The approach uses Markov Chain Monte Carlo posterior simulations to estimate the evidence in favor of competing models and, in this study, three known methods for doing this are compared in terms of their suitability for being incorporated into the proposed BMS framework for ANNs. However, it is acknowledged that it can be particularly difficult to accurately estimate the evidence of ANN models. Therefore, the proposed BMS approach for ANNs incorporates a further check of the evidence results by inspecting the marginal posterior distributions of the hidden-to-output layer weights, which unambiguously indicate any redundancies in the hidden layer nodes. The fact that this check is available is one of the greatest advantages of the proposed approach over conventional model selection methods, which do not provide such a test and instead rely on the modeler's subjective choice of selection criterion. The advantages of a total Bayesian approach to ANN development, including training and model selection, are demonstrated on two synthetic and one real world water resources case study.
DOE Office of Scientific and Technical Information (OSTI.GOV)
Barran, Perdita; Baker, Erin
The great complexity of biological systems and their environment poses similarly vast challenges for accurate analytical evaluations of their identity, structure and quantity. Post genomic science, has predicted much regarding the static populations of biological systems, but a further challenge for analysis is to test the accuracy of these predictions, as well as provide a better representation of the transient nature of the molecules of life. Accurate measurements of biological systems have wide applications for biological, forensic, biotechnological and healthcare fields. Therefore, the holy grail is to find a technique which can identify and quantify biological molecules with high throughput,more » sensitivity and robustness, as well evaluate molecular structure(s) in order to understand how the specific molecules interact and function. While wrapping all of these characteristics into one platform may sound difficult, ion mobility spectrometry (IMS) is addressing all of these challenges. Over the last decade, the number of analytical studies utilizing IMS for the evaluation of complex biological and environmental samples has greatly increased. In most cases IMS is coupled with mass spectrometry (IM-MS), but even alone IMS provides the unique capability of rapidly assessing a molecule’s structure, which can be extremely difficult with other techniques. The robustness of the IMS measurement is bourne out by its widespread use in security, environmental and military applications. The multidimensional IM-MS measurements however have been proven to be ever more powerful, as applied to complex mixtures as they enable the evaluation of both the structure and mass of every molecular component in a sample during a single measurement, without the need for continual reference calibration.« less
Estimation of population size using open capture-recapture models
McDonald, T.L.; Amstrup, Steven C.
2001-01-01
One of the most important needs for wildlife managers is an accurate estimate of population size. Yet, for many species, including most marine species and large mammals, accurate and precise estimation of numbers is one of the most difficult of all research challenges. Open-population capture-recapture models have proven useful in many situations to estimate survival probabilities but typically have not been used to estimate population size. We show that open-population models can be used to estimate population size by developing a Horvitz-Thompson-type estimate of population size and an estimator of its variance. Our population size estimate keys on the probability of capture at each trap occasion and therefore is quite general and can be made a function of external covariates measured during the study. Here we define the estimator and investigate its bias, variance, and variance estimator via computer simulation. Computer simulations make extensive use of real data taken from a study of polar bears (Ursus maritimus) in the Beaufort Sea. The population size estimator is shown to be useful because it was negligibly biased in all situations studied. The variance estimator is shown to be useful in all situations, but caution is warranted in cases of extreme capture heterogeneity.
NASA Astrophysics Data System (ADS)
Thebault, P.; Haghighipour, N.
Spurred by the discovery of numerous exoplanets in multiple systems, binaries have become in recent years one of the main topics in planet formation research. Numerous studies have investigated to what extent the presence of a stellar companion can affect the planet formation process. Such studies have implications that can reach beyond the sole context of binaries, as they allow to test certain aspects of the planet formation scenario by submitting them to extreme environments. We review here the current understanding on this complex problem. We show in particular how each of the different stages of the planet-formation process is affected differently by binary perturbations. We focus especially on the intermediate stage of kilometre-sized planetesimal accretion, which has proven to be the most sensitive to binarity and for which the presence of some exoplanets observed in tight binaries is difficult to explain by in-situ formation following the "standard" planet-formation scenario. Some tentative solutions to this apparent paradox are presented. The last part of our review presents a thorough description of the problem of planet habitability, for which the binary environment creates a complex situation because of the presence of two irradation sources of varying distance.
Volume of Impact Melt Generated by the Formation of the South Pole-Aitken Basin
NASA Technical Reports Server (NTRS)
Petro, Noah E.
2011-01-01
The South Pole-Aitken Basin (SPA) is the largest, deepest, and oldest identified basin on the Moon and as such contains surfaces that are unique due to their age, composition, and depth of origin in the lunar crust [1-5] (Figure 1). SPA has been a target of intense interest as an area for robotic sample return in order to determine the age of the basin and the composition and origin of its interior [6-8]. In response to this interest there have been several efforts to estimate the likely provenance of regolith material within central SPA [9-12]. These model estimates suggest that, despite the formation of basins and craters following SPA, the regolith within SPA is dominated by locally derived material. An assumption of these models has been that the locally derived material is primarily SPA impact-melt as opposed to local basement material (e.g. unmelted lower crust). However, the definitive identification of SPA derived impact melt on the basin floor, either by remote sensing [5, 13] or via photogeology [2, 14] is extremely difficult due to the number of subsequent impacts and volcanic activity [4].
A model for competitiveness level analysis in sports competitions: Application to basketball
NASA Astrophysics Data System (ADS)
de Saá Guerra, Y.; Martín González, J. M.; Sarmiento Montesdeoca, S.; Rodríguez Ruiz, D.; García-Rodríguez, A.; García-Manso, J. M.
2012-05-01
The degree of overall competitiveness of a sport league is a complex phenomenon. It is difficult to assess and quantify all elements that yield the final standing. In this paper, we analyze the general behavior of the result matrices of each season and we use the corresponding results as a probably density. Thus, the results of previous seasons are a way to investigate the probability that each team has to reach a certain number of victories. We developed a model based on Shannon entropy using two extreme competitive structures (a hierarchical structure and a random structure), and applied this model to investigate the competitiveness of two of the best professional basketball leagues: the NBA (USA) and the ACB (Spain). Both leagues’ entropy levels are high (NBA mean 0.983; ACB mean 0.980), indicating high competitiveness, although the entropy of the ACB (from 0.986 to 0.972) demonstrated more seasonal variability than that of the NBA (from 0.985 to 0.990), a possible result of greater sporting gradients in the ACB. The use of this methodology has proven useful for investigating the competitiveness of sports leagues as well as their underlying variability across time.
The Highly-Automated Airplane: Its Impact on Aviation Safety and an Analysis of Training Philosophy.
1997-06-01
equipment. This means more than just knowing how to program the device and being familiar with the functions of varying modes (Patrick, 1996:18). 33...the function that I wanted to use or modify in a flight plan." "Initially it is extremely difficult to figure out exactly how to program or pull up...commented: "Getting used to the EFIS display was the hardest. Initially it is extremely difficult to figure out exactly how to program or pull up the
Teaching Proportional Reasoning through Familiar Biology
ERIC Educational Resources Information Center
Burger, Lance
2010-01-01
Constructivism has constituted a predominant philosophical trend in mathematics education, but its implementation in the classroom has proven to be "far more difficult than the reform community acknowledges". This difficulty may be due in part to administrative cultures that might insist on more procedural types of instruction aimed at testing, in…
Why Linking Budgets to Plans Has Proven Difficult in Higher Education.
ERIC Educational Resources Information Center
Schmidtlein, Frank A.
1990-01-01
Conclusions from two studies (including a three-year nationwide study of higher education institutional planning) concern types of planning (strategic, program, facility, operational, budget, and issue-specific), and limitations (the limited powers of prediction and the political character of planning and budgeting). Types of budgeting processes…
Critical Assessment Issues in Work-Integrated Learning
ERIC Educational Resources Information Center
Ferns, Sonia; Zegwaard, Karsten E.
2014-01-01
Assessment has long been a contentious issue in work-integrated learning (WIL) and cooperative education. Despite assessment being central to the integrity and accountability of a university and long-standing theories around best practice in assessment, enacting quality assessment practices has proven to be more difficult. Authors in this special…
Forensic Analysis of Cites-Protected Dalbergia Timber from the Americas
Edgard O. Espinoza; Michael C. Wiemann; Josefina Barajas-Morales; Gabriela D. Chavarria; Pamela J. McClure
2015-01-01
Species identification of logs, planks, and veneers is difficult because they lack the traditional descriptors such as leaves and flowers. An additional challenge is that many transnational shipments have unreliable geographic provenance. Therefore, frequently the lowest taxonomic determination is genus, which allows unscrupulous importers to evade the endangered...
Multi-species pheromone-based mating disruption: Moth birth control in cranberries
USDA-ARS?s Scientific Manuscript database
Pheromone-based mating disruption is a proven method of pest control, but in cranberries, tailoring this technology to modern production practices has been difficult. Using the wax carrier, SPLAT, we have overcome many of these difficulties and now have three years of data suggesting that mating dis...
Resolving the Evolution of Extant and Extinct Ruminants With High-Throughput Phylogenomics
USDA-ARS?s Scientific Manuscript database
The Pecorans (higher ruminants) are believed to have rapidly speciated in the Mid-Eocene, resulting in five distinct extant families; Antilocapridae, Giraffidae, Moschidae, Cervidae, and Bovidae. Due to the rapid radiation, the Pecoran phylogeny has proven difficult to resolve and eleven of the fift...
Development of northern red oak rooted cutting and enrichment planting systems
Matthew H. Gocke; Jamie Schuler; Daniel J. Robison; Barry Goldfarb
2005-01-01
Enrichment planting may provide an efficient means to establish elite northern red oak (Quercus rubra L.) genotypes in recently harvested natural forests. However, planting northern red oak (NRO) seedlings into natural stands has proven difficult in the past, especially when competition and other stress factors are not controlled.
Deficit irrigation: Arriving at the crop water stress index via gas exchange measurements
USDA-ARS?s Scientific Manuscript database
Plant gas exchange provides a highly sensitive measure of the degree of drought stress. Canopy temperature (Tc) provides a much easier to acquire indication of crop water deficit that has been used in irrigation scheduling systems, but interpretation of this measurement has proven difficult. Our goa...
GREAT LAKES BASIN LAND-COVER DATA: ISSUES AND OPPORTUNITIES
The US Environmental Protection Agency (EPA) is developing a consistent land-cover (LC) data set for the entire 480,000 km2 Great Lakes Basin (GLB). The acquisition of consistent LC data has proven difficult both within the US and across GLB political boundaries due to disparate...
How Can We Improve Preventive and Educational Interventions for Intimate Relationships?
ERIC Educational Resources Information Center
Bradbury, Thomas N.; Lavner, Justin A.
2012-01-01
Improving intimate relationships with preventive and educational interventions has proven to be more difficult than originally conceived, and earlier models and approaches may be reaching their limits. Basic concerns remain about the long-term effectiveness of these interventions, whether they are reaching and benefiting couples most likely to…
Construct Validation of the Behavior and Instructional Management Scale
ERIC Educational Resources Information Center
Martin, Nancy K.; Sass, Daniel A.
2010-01-01
Beliefs related to classroom management vary among teachers and play an important role in classrooms. Despite the importance of this construct, valid measures have proven difficult to develop. This study evaluated the psychometric properties of the Behavior and Instructional Management Scale (BIMS), a short but valid measure of teachers'…
ERIC Educational Resources Information Center
LaGrandeur, Kevin
Computer mediated communication (CMC) tends to erase power structures because such communication somehow undermines or escapes discursive limits. Online discussions seem to promote rhetorical experimentation on the part of the participants. Finding a way to explain disparities between electronic discussion and oral discussion has proven difficult.…
Framing Indigenous Languages as Secondary to Matrix Languages
ERIC Educational Resources Information Center
Meek, Barbra A.; Messing, Jacqueline
2007-01-01
Reversing language shift has proven to be difficult for many reasons. Although much of the literature has focused on educational practices, little research has attended to the visual presentation of language used in educational texts aimed at reversing shift. In this article, we compare language materials developed for two different language…
Development and Evaluation of the School Cafeteria Nutrition Assessment Measures
ERIC Educational Resources Information Center
Krukowski, Rebecca A.; Philyaw Perez, Amanda G.; Bursac, Zoran; Goodell, Melanie; Raczynski, James M.; Smith West, Delia; Phillips, Martha M.
2011-01-01
Background: Foods provided in schools represent a substantial portion of US children's dietary intake; however, the school food environment has proven difficult to describe due to the lack of comprehensive, standardized, and validated measures. Methods: As part of the Arkansas Act 1220 evaluation project, we developed the School Cafeteria…
Next-Generation Long-Range Strike: Combating the Tyranny of Distance
2011-02-16
and other subsystems such as fuel, hydraulics, ejection seats , etc. from proven and fielded systems. To enable the optionally manned capability...weapon is a very difficult target to engage. Surface-to- air missile kinematics simply cannot match that of a hypersonic weapon enabling more targets to
USDA-ARS?s Scientific Manuscript database
Antimicrobial polymeric films that are both mechanically robust and function renewable would have broad technological implications for areas ranging from medical safety and bioengineering to foods industry; however, creating such materials has proven extremely challenging. Here, a novel strategy is ...
NASA Astrophysics Data System (ADS)
Seidel, Hannes; Schunk, Christian; Matiu, Michael; Menzel, Annette
2016-04-01
Climate warming and more frequent and severe drought events will alter the adaptedness and fitness of tree species. Especially, Scots pine forests have been affected above average by die-off events during the last decades. Assisted migration of adapted provenances might help alleviating impacts by recent climate change and successfully regenerating forests. However, the identification of suitable provenances based on established ecophysiological methods is time consuming, sometimes invasive, and data on provenance-specific mortality are lacking. We studied the performance, stress and survival of potted Scots pine seedlings from 12 European provenances grown in a greenhouse experiment with multiple drought and warming treatments. In this paper, we will present results of drought stress impacts monitored with four different thermal indices derived from infrared thermography imaging as well as an ample mortality study. Percent soil water deficit (PSWD) was shown to be the main driver of drought stress response in all thermal indices. In spite of wet and dry reference surfaces, however, fluctuating environmental conditions, mainly in terms of air temperature and humidity, altered the measured stress response. In linear mixed-effects models, besides PSWD and meteorological covariates, the factors provenance and provenance - PSWD interactions were included. The explanatory power of the models (R2) ranged between 0.51 to 0.83 and thus, provenance-specific responses to strong and moderate drought and subsequent recovery were revealed. However, obvious differences in the response magnitude of provenances to drought were difficult to explicitly link to general features such Mediterranean - continental type or climate at the provenances' origin. We conclude that seedlings' drought resistance may be linked to summer precipitation and their experienced stress levels are a.o. dependent on their above ground dimensions under given water supply. In respect to mortality, previous drought stress experience lowered the current risk and obvious provenance effects were largely related to different growth traits (dimensions). Our experimental results suggest besides evidence for abiotic stress hardening provenance-specific variation in drought resilience. Thus, there is room for provenance-based assisted migration as tool for climate change adaptation in forestry.
Ekstrand, Elisabeth; Rylander, Lars; Lexell, Jan; Brogårdh, Christina
2016-11-02
Despite that disability of the upper extremity is common after stroke, there is limited knowledge how it influences self-perceived ability to perform daily hand activities. The aim of this study was to describe which daily hand activities that persons with mild to moderate impairments of the upper extremity after stroke perceive difficult to perform and to evaluate how several potential factors are associated with the self-perceived performance. Seventy-five persons (72 % male) with mild to moderate impairments of the upper extremity after stroke (4 to 116 months) participated. Self-perceived ability to perform daily hand activities was rated with the ABILHAND Questionnaire. The perceived ability to perform daily hand activities and the potentially associated factors (age, gender, social and vocational situation, affected hand, upper extremity pain, spasticity, grip strength, somatosensation of the hand, manual dexterity, perceived participation and life satisfaction) were evaluated by linear regression models. The activities that were perceived difficult or impossible for a majority of the participants were bimanual tasks that required fine manual dexterity of the more affected hand. The factor that had the strongest association with perceived ability to perform daily hand activities was dexterity (p < 0.001), which together with perceived participation (p = 0.002) explained 48 % of the variance in the final multivariate model. Persons with mild to moderate impairments of the upper extremity after stroke perceive that bimanual activities requiring fine manual dexterity are the most difficult to perform. Dexterity and perceived participation are factors specifically important to consider in the rehabilitation of the upper extremity after stroke in order to improve the ability to use the hands in daily life.
Comparison of postfire seeding practices for Wyoming big sagebrush
Jeffrey E. Ott; Robert D. Cox; Nancy L. Shaw
2017-01-01
Wildfires in the Great Basin have resulted in widespread loss of Wyoming big sagebrush (Artemisia tridentata Nutt. ssp. wyomingensis Beetle & Young), an ecologically important shrub that has proven difficult to establish from seed.We sought to identify optimal seeding practices forWyoming big sagebrush in the context of postfire seeding operations involving...
A New Consensus for Undergraduate Education: Can We Get There from Here?
ERIC Educational Resources Information Center
Shoenberg, Robert E.
2007-01-01
Business executives, government leaders and educators concerned with undergraduate curriculum are converging on a set of college outcomes necessary for success in the global society of the 21st century. Yet moving postsecondary education toward a curriculum that embraces these outcomes has proven difficult. The preoccupations of faculty members,…
ERIC Educational Resources Information Center
James, Richard A.
2013-01-01
In standards-based education the importance of interpreting standards and effectively embedding them into instructional design is critical in connecting curriculum and instruction. Finding the link between standards and instruction while striving to engage students has proven difficult. Too often instructional design does not meet the cognitive…
The Intersection of Dialogue and Low Transactional Distance: Considerations for Higher Education
ERIC Educational Resources Information Center
Farquhar, Lynn
2013-01-01
The theory of transactional distance has been subjected to a variety of empirical tests and philosophical critiques. Throughout this process, the variable of dialogue has attracted much attention. Although dialogue has proven difficult to measure and define, it is widely regarded as an ideal outcome of the teacher-learner transaction. Considered…
Moisture dynamics in masticated fuelbeds: A preliminary analysis
Jesse Kreye; J. Morgan Varner
2007-01-01
Mastication has become a popular fuels treatment in the Western United States, but predicting subsequent fire behavior and effects has proven difficult. Fire behavior and effects in masticated fuelbeds have been more intense and erratic in comparison with model predictions. While various particle or fuelbed characteristics in these fuels may contribute to the...
Prospects for Gene Therapy in the Fragile X Syndrome
ERIC Educational Resources Information Center
Rattazzi, Mario C.; LaFauci, Giuseppe; Brown, W. Ted
2004-01-01
Gene therapy is unarguably the definitive way to treat, and possibly cure, genetic diseases. A straightforward concept in theory, in practice it has proven difficult to realize, even when directed to easily accessed somatic cell systems. Gene therapy for diseases in which the central nervous system (CNS) is the target organ presents even greater…
In Practice: Virtual Job Club--A Social Support Network for Recent Graduates
ERIC Educational Resources Information Center
Maietta, Heather N.
2012-01-01
Searching for employment during this recession-battered market has proven difficult for many new college graduates. As unemployment trends and hiring outlooks continue their slow resurgence, the competition for jobs remains fierce, and the students are feeling the pressure. In this article, the author describes Nichols College's new, web-based…
USDA-ARS?s Scientific Manuscript database
Gene silencing through RNA interference (RNAi) has revolutionized the study of gene function, particularly in non-model insects. However, in Lepidoptera (moths and butterflies) RNAi has many times proven to be difficult to achieve. Most of the negative results have been anecdotal and the positive ex...
Evolutionary computing for the design search and optimization of space vehicle power subsystems
NASA Technical Reports Server (NTRS)
Kordon, M.; Klimeck, G.; Hanks, D.
2004-01-01
Evolutionary computing has proven to be a straightforward and robust approach for optimizing a wide range of difficult analysis and design problems. This paper discusses the application of these techniques to an existing space vehicle power subsystem resource and performance analysis simulation in a parallel processing environment.
A Formal Construction of Term Classes. Technical Report No. TR73-18.
ERIC Educational Resources Information Center
Yu, Clement T.
The computational complexity of a formal process for the construction of term classes for information retrieval is examined. While the process is proven to be difficult computationally, heuristic methods are applied. Experimental results are obtained to illustrate the maximum possible improvement in system performance of retrieval using the formal…
The Utility of Interaction Analysis for Generalizing Characteristics of Science Classrooms
ERIC Educational Resources Information Center
Crippen, Kent J.; Sangueza, Cheryl R.
2013-01-01
Validating and generalizing from holistic observation protocols of classroom practice have proven difficult. These tools miss crucial classroom characteristics, like the type of instruction, the organization of learners, and the level of cognitive engagement that occur differentially in the time span of a lesson. As a result, this study examined…
Gestural Characterization of a Phonological Class: The Liquids
ERIC Educational Resources Information Center
Proctor, Michael Ian
2009-01-01
Rhotics and laterals pattern together in a variety of ways that suggest that they form a phonological class (Walsh-Dickey 1997), yet capturing the relevant set of consonants and describing the behavior of its members has proven difficult under feature-based phonological theory (Wiese 2001). In this dissertation, I argue that an articulatory…
George, Jan-Peter; Grabner, Michael; Karanitsch-Ackerl, Sandra; Mayer, Konrad; Weißenbacher, Lambert; Schueler, Silvio
2017-01-01
Abstract Assessing intra-specific variation in drought stress response is required to mitigate the consequences of climate change on forest ecosystems. Previous studies suggest that European larch (Larix decidua Mill.), an important European conifer in mountainous and alpine forests, is highly vulnerable to drought. In light of this, we estimated the genetic variation in drought sensitivity and its degree of genetic determination in a 50-year-old common garden experiment in the drought-prone northeastern Austria. Tree ring data from larch provenances originating from across the species' natural range were used to estimate the drought reaction in four consecutive drought events (1977, 1981, 1990–1994, and 2003) with extremely low standardized precipitation- and evapotranspiration-index values that affected growth in all provenances. We found significant differences among provenances across the four drought periods for the trees’ capacity to withstand drought (resistance) and for their capacity to reach pre-drought growth levels after drought (resilience). Provenances from the species' northern distribution limit in the Polish lowlands were found to be more drought resistant and showed higher stability across all drought periods than provenances from mountainous habitats at the southern fringe. The degree of genetic determination, as estimated by the repeatability, ranged up to 0.39, but significantly differed among provenances, indicating varying degrees of natural selection at the provenance origin. Generally, the relationship between the provenances’ source climate and drought behavior was weak, suggesting that the contrasting patterns of drought response are a result of both genetic divergence out of different refugial lineages and local adaptation to summer or winter drought conditions. Our analysis suggests that European larch posseses high genetic variation among and within provenances that can be used for assisted migration and breeding programs. PMID:28173601
DOE Office of Scientific and Technical Information (OSTI.GOV)
Wang, Jiali; Han, Yuefeng; Stein, Michael L.
2016-02-10
The Weather Research and Forecast (WRF) model downscaling skill in extreme maximum daily temperature is evaluated by using the generalized extreme value (GEV) distribution. While the GEV distribution has been used extensively in climatology and meteorology for estimating probabilities of extreme events, accurately estimating GEV parameters based on data from a single pixel can be difficult, even with fairly long data records. This work proposes a simple method assuming that the shape parameter, the most difficult of the three parameters to estimate, does not vary over a relatively large region. This approach is applied to evaluate 31-year WRF-downscaled extreme maximummore » temperature through comparison with North American Regional Reanalysis (NARR) data. Uncertainty in GEV parameter estimates and the statistical significance in the differences of estimates between WRF and NARR are accounted for by conducting bootstrap resampling. Despite certain biases over parts of the United States, overall, WRF shows good agreement with NARR in the spatial pattern and magnitudes of GEV parameter estimates. Both WRF and NARR show a significant increase in extreme maximum temperature over the southern Great Plains and southeastern United States in January and over the western United States in July. The GEV model shows clear benefits from the regionally constant shape parameter assumption, for example, leading to estimates of the location and scale parameters of the model that show coherent spatial patterns.« less
Social Network Analysis in E-Learning Environments: A Preliminary Systematic Review
ERIC Educational Resources Information Center
Cela, Karina L.; Sicilia, Miguel Ángel; Sánchez, Salvador
2015-01-01
E-learning occupies an increasingly prominent place in education. It provides the learner with a rich virtual network where he or she can exchange ideas and information and create synergies through interactions with other members of the network, whether fellow learners or teachers. Social network analysis (SNA) has proven extremely powerful at…
Do you really know where this SNP goes?
USDA-ARS?s Scientific Manuscript database
The release of build 10.2 of the swine genome was a marked improvement over previous builds and has proven extremely useful. However, as most know, there are regions of the genome that this particular build does not accurately represent. For instance, nearly 25% of the 62,162 SNP on the Illumina Por...
NASA Astrophysics Data System (ADS)
Mutua, F.; Koike, T.
2013-12-01
Extreme weather events have been the leading cause of disasters and damage all over the world.The primary ingredient to these disasters especially floods is rainfall which over the years, despite advances in modeling, computing power and use of new data and technologies, has proven to be difficult to predict. Also, recent climate projections showed a pattern consistent with increase in the intensity and frequency of extreme events in the East African region.We propose a holistic integrated approach to climate change assessment and extreme event adaptation through coupling of analysis techniques, tools and data. The Lake Victoria Basin (LVB) in East Africa supports over three million livelihoods and is a valuable resource to five East African countries as a source of water and means of transport. However, with a Mesoscale weather regime driven by land and lake dynamics,extreme Mesoscale events have been prevalent and the region has been on the receiving end during anomalously wet years in the region. This has resulted in loss of lives, displacements, and food insecurity. In the LVB, the effects of climate change are increasingly being recognized as a significant contributor to poverty, by its linkage to agriculture, food security and water resources. Of particular importance are the likely impacts of climate change in frequency and intensity of extreme events. To tackle this aspect, this study adopted an integrated regional, mesoscale and basin scale approach to climate change assessment. We investigated the projected changes in mean climate over East Africa, diagnosed the signals of climate change in the atmosphere, and transferred this understanding to mesoscale and basin scale. Changes in rainfall were analyzed and similar to the IPCC AR4 report; the selected three General Circulation Models (GCMs) project a wetter East Africa with intermittent dry periods in June-August. Extreme events in the region are projected to increase; with the number of wet days exceeding the 90% percentile of 1981-2000 likely to increase by 20-40% in the whole region. We also focused on short-term weather forecasting as a step towards adapting to a changing climate. This involved dynamic downscaling of global weather forecasts to high resolution with a special focus on extreme events. By utilizing complex model dynamics, the system was able to reproduce the Mesoscale dynamics well, simulated the land/lake breeze and diurnal pattern but was inadequate in some aspects. The quantitative prediction of rainfall was inaccurate with overestimation and misplacement but with reasonable occurrence. To address these shortcomings we investigated the value added by assimilating Advanced Microwave Scanning Radiometer (AMSR-E) brightness temperature during the event. By assimilating 23GHz (sensitive to water) and 89GHz (sensitive to cloud) frequency brightness temperature; the predictability of an extreme rain weather event was investigated. The assimilation through a Cloud Microphysics Data Assimilation (CMDAS) into the weather prediction model considerably improved the spatial distribution of this event.
What Does a Verbal Test Measure? A New Approach to Understanding Sources of Item Difficulty.
ERIC Educational Resources Information Center
Berk, Eric J. Vanden; Lohman, David F.; Cassata, Jennifer Coyne
Assessing the construct relevance of mental test results continues to present many challenges, and it has proven to be particularly difficult to assess the construct relevance of verbal items. This study was conducted to gain a better understanding of the conceptual sources of verbal item difficulty using a unique approach that integrates…
ERIC Educational Resources Information Center
Metsala, Jamie L.; David, Margaret D.
2017-01-01
For students with reading disabilities, reading fluency has proven difficult to remediate. The current study examined age-related effects on measures of word and text-reading outcomes, within the context of a phonologically based remedial reading program. The contribution of speeded-reading of sublexical sound-spelling patterns to fluency outcomes…
Multiobjective Optimization Using a Pareto Differential Evolution Approach
NASA Technical Reports Server (NTRS)
Madavan, Nateri K.; Biegel, Bryan A. (Technical Monitor)
2002-01-01
Differential Evolution is a simple, fast, and robust evolutionary algorithm that has proven effective in determining the global optimum for several difficult single-objective optimization problems. In this paper, the Differential Evolution algorithm is extended to multiobjective optimization problems by using a Pareto-based approach. The algorithm performs well when applied to several test optimization problems from the literature.
Closing the College Completion Gap: A Guidebook for the Faith Community
ERIC Educational Resources Information Center
Moore, Laura A.; Bridgeland, John M.; DiIulio, John J., Jr.
2010-01-01
A degree beyond high school has become an essential element of opportunity in America and is a proven pathway out of poverty. However, the majority of our nation's young people, especially low-income Americans, are finding it difficult to complete this pathway to success. Every day, there are faith communities throughout the country that are…
ERIC Educational Resources Information Center
Sonn, Andrew C.
2009-01-01
While facing difficult financial times, student affairs divisions and their leaders are increasingly considering collaborating with development officers and other institutional partners to raise funds for student services, activities, and facilities. Student affairs leaders, however, do not have proven strategies based on empirical data for making…
USDA-ARS?s Scientific Manuscript database
Chronic wasting disease (CWD) is an efficiently transmitted spongiform encephalopathy of cervids (e.g. deer, elk, and moose), and is the only known prion disease affecting both free-ranging wildlife and captive animals. The antemortem detection of CWD and other prion diseases has proven difficult, d...
ERIC Educational Resources Information Center
Kish, Stacy
2008-01-01
Obesity among children and adults has reached epidemic proportions in the United States. This condition has proven difficult to treat effectively, especially in terms of sustainable weight loss. The project described in this report embarked on multidimensional, community-based efforts to prompt a national discussion of the obesity issue and the…
ERIC Educational Resources Information Center
Carnegie Council on Adolescent Development, Washington, DC.
This symposium addressed key findings of the Carnegie Council on Adolescent Development-sponsored book "Promoting the Health of Adolescents: New Directions for the Twenty-First Century." A panel of experts focused on science policy implications of critical issues in adolescent health promotion that have proven difficult to address such…
ERIC Educational Resources Information Center
Hieneman, Meme; Childs, Karen; Sergay, Jane
2006-01-01
Now the theory and research behind the positive behavior support (PBS) process--an approach already proven effective in schools and community programs--has been transformed into a practical, easy-to-use guide that's perfect for sharing with parents. Developed by educators and families, this user-friendly handbook offers parents easy-to-follow…
ERIC Educational Resources Information Center
Zimmer-Gembeck, Melanie J.; Skinner, Ellen A.
2011-01-01
Despite consensus that development shapes every aspect of coping, studies of age differences in coping have proven difficult to integrate, primarily because they examine largely unselected age groups, and utilize overlapping coping categories. A developmental framework was used to organize 58 studies of coping involving over 250 age comparisons or…
John B. Loomis; George Peterson; Patricia A. Champ; Thomas C. Brown; Beatrice Lucero
1998-01-01
Estimating empirical measures of an individual's willingness to accept that are consistent with conventional economic theory, has proven difficult. The method of paired comparison offers a promising approach to estimate willingness to accept. This method involves having individuals make binary choices between receiving a particular good or a sum of money....
Neurosurgical rare disease: solitary plasmacytoma of the skull - case report and literature review.
Rizea, Radu Eugen; Popescu, Mihai; Gheorghiţă, Karina Lidia; Popescu, George; Neamţu, Marius Cristian; Busuioc, Cristina Jana; Ciurea, Alexandru Vlad
2018-01-01
Solitary extranevraxial plasmacytoma (SEP), as a clinical entity without signs of systemic myelomatosis, is extremely rare; it is difficult to find literature on the issue of patient management and proper course of action in the presence of associated pathology. The authors present a rare case of plasmacytoma of the skull vault associated with severe cardiac pathology, which made surgery extremely difficult and possible only through temporization of the interventions, as presented. We discuss our findings and opportunities for treatment in this case, which seemed unapproachable at presentation, in connection with the associated cardiac pathology. The case was followed-up for eight years with no recurrences.
Complex layered dental restorations: Are they recognizable and do they survive extreme conditions?
Soon, Alistair S; Bush, Mary A; Bush, Peter J
2015-09-01
Recent research has shown that restorative dental materials can be recognized by microscopy and elemental analysis (scanning electron microscopy/energy dispersive X-ray spectroscopy and X-ray fluorescence; SEM/EDS and XRF) and that this is possible even in extreme conditions, such as cremation. These analytical methods and databases of dental materials properties have proven useful in DVI (disaster victim identification) of a commercial plane crash in 2009, and in a number of other victim identification cases. Dental materials appear on the market with ever expanding frequency. With their advent, newer methods of restoration have been proposed and adopted in the dental office. Methods might include placing multiple layers of dental materials, where they have different properties including adhesion, viscosity, or working time. These different dental materials include filled adhesives, flowable resins, glass ionomer cements, composite resins, liners and sealants. With possible combinations of different materials in these restorations, the forensic odontologist is now confronted with a new difficulty; how to recognize each individual material. The question might be posed if it is even possible to perform this task. Furthermore, an odontologist might be called upon to identify a victim under difficult circumstances, such as when presented with fragmented or incinerated remains. In these circumstances the ability to identify specific dental materials could assist in the identification of the deceased. Key to use of this information is whether these new materials and methods are detailed in the dental chart. Visual or radiographic inspection may not reveal the presence of a restoration, let alone the possible complex nature of that restoration. This study demonstrates another scientific method in forensic dental identification. Copyright © 2015 Elsevier Ireland Ltd. All rights reserved.
DOE Office of Scientific and Technical Information (OSTI.GOV)
Wilbanks, Thomas J.; Fernandez, Steven J.; Allen, Melissa R.
The President s Climate Change Action Plan calls for the development of better science, data, and tools for climate preparedness. Many of the current questions about preparedness for extreme weather events in coming decades are, however, difficult to answer with assets that have been developed by climate science to answer longer-term questions about climate change. Capacities for projecting exposures to climate-related extreme events, along with their implications for interconnected infrastructures, are now emerging.
Wilbanks, Thomas J.; Fernandez, Steven J.; Allen, Melissa R.
2015-06-23
The President s Climate Change Action Plan calls for the development of better science, data, and tools for climate preparedness. Many of the current questions about preparedness for extreme weather events in coming decades are, however, difficult to answer with assets that have been developed by climate science to answer longer-term questions about climate change. Capacities for projecting exposures to climate-related extreme events, along with their implications for interconnected infrastructures, are now emerging.
Courting, Marriage and Death in Colombia: An Interview.
ERIC Educational Resources Information Center
Richardson, Constance
There are a variety of methods to impart the cultural setting of a foreign language. The teacher can use, among other things, cultural assimilators, films, mini-dramas, culture capsules, background lectures, and native-speaking class visitors. This last technique can be extremely effective but difficult to arrange and difficult to control once it…
Learned Helplessness: The Effect of Failure on Test-Taking
ERIC Educational Resources Information Center
Firmin, Michael; Hwang, Chi-En; Copella, Margaret; Clark, Sarah
2004-01-01
This study examined learned helplessness and its effect on test taking. Students were given one of two tests; the first began with extremely difficult questions and the other started with easy questions. The researchers hypothesized that those who took the test beginning with difficult questions would become easily frustrated and possibly doubt…
Predicting the Magnetic Properties of ICMEs: A Pragmatic View
NASA Astrophysics Data System (ADS)
Riley, P.; Linker, J.; Ben-Nun, M.; Torok, T.; Ulrich, R. K.; Russell, C. T.; Lai, H.; de Koning, C. A.; Pizzo, V. J.; Liu, Y.; Hoeksema, J. T.
2017-12-01
The southward component of the interplanetary magnetic field plays a crucial role in being able to successfully predict space weather phenomena. Yet, thus far, it has proven extremely difficult to forecast with any degree of accuracy. In this presentation, we describe an empirically-based modeling framework for estimating Bz values during the passage of interplanetary coronal mass ejections (ICMEs). The model includes: (1) an empirically-based estimate of the magnetic properties of the flux rope in the low corona (including helicity and field strength); (2) an empirically-based estimate of the dynamic properties of the flux rope in the high corona (including direction, speed, and mass); and (3) a physics-based estimate of the evolution of the flux rope during its passage to 1 AU driven by the output from (1) and (2). We compare model output with observations for a selection of events to estimate the accuracy of this approach. Importantly, we pay specific attention to the uncertainties introduced by the components within the framework, separating intrinsic limitations from those that can be improved upon, either by better observations or more sophisticated modeling. Our analysis suggests that current observations/modeling are insufficient for this empirically-based framework to provide reliable and actionable prediction of the magnetic properties of ICMEs. We suggest several paths that may lead to better forecasts.
NASA Astrophysics Data System (ADS)
Tillmann, W.; Henning, T.; Wojarski, L.
2018-06-01
Many industrial applications require components with an increasing geometric complexity and specific material properties. Furthermore, the production costs and the affordable production time have to be minimized in order to ensure competitiveness. These divergent objectives are difficult to achieve with a single manufacturing technology. Therefore, joining of selective laser melted (SLM) complex shaped parts to conventionally produced high-volume components provides a high potential. The current investigation focuses on vacuum brazing conventionally manufactured to non-hipped SLM generated AISI 316L stainless steel. Cylindrical samples (Ø 14 mm) were brazed using a B-Ni2 foil (50 µm) at 1050 °C for 30 minutes in vacuum (< 4.5·10-5 mbar) and directly cooled down to room temperature with 4 bar overpressure to prevent the formation of chromium carbides within the base material. It could be proven that the brazing quality is extremely sensitive to even marginal porosities (< 0.2 %) and/or oxide inclusions of the SLM microstructure. Therefore, the fracture mirror in SLM/conventional steel brazements was at the joint braze/SLM steel interface, leading to a joint strength of 317.4 MPa. This corresponds to only 67.4 % of the joint strength obtained with conventional steel, where the fracture propagated through the diffusion area.
NASA Astrophysics Data System (ADS)
Fisher, Mark; Sikes, John; Prather, Mark
2004-09-01
The dog's nose is an effective, highly-mobile sampling system, while the canine olfactory organs are an extremely sensitive detector. Having been trained to detect a wide variety of substances with exceptional results, canines are widely regarded as the 'gold standard' in chemical vapor detection. Historically, attempts to mimic the ability of dogs to detect vapors of explosives using electronic 'dogs noses' has proven difficult. However, recent advances in technology have resulted in development of detection (i.e., sampling and sensor) systems with performance that is rapidly approaching that of trained canines. The Nomadics Fido was the first sensor to demonstrate under field conditions the detection of landmines with performance approaching that of canines. More recently, comparative testing of Fido against canines has revealed that electronic vapor detection, when coupled with effective sampling methods, can produce results comparable to that of highly-trained canines. The results of these comparative tests will be presented, as will recent test results in which explosives hidden in cargo were detected using Fido with a high-volume sampling technique. Finally, the use of canines along with electronic sensors will be discussed as a means of improving the performance and expanding the capabilities of both methods.
Improved LCI profile of LAB based on latest technology advances
DOE Office of Scientific and Technical Information (OSTI.GOV)
Berna, J.L.; Renta, C.
1995-12-31
The first technology used to produce LAB was introduced in the early 60`s and since then a continuous optimization process has taken place on this highly competitive product on which additional cost effectiveness improvements became highly challenging. The latest technology introduced in the market (CEPSA {minus} UOP DETAL) based on a fixed bed alkylation process, has already been proved on a commercial scale. The simplicity of the new technology as compared to current ones, namely HF, has proven to be very effective in reducing substantially the impact due to several major components of the Life Cycle Inventory (LCI) in particularmore » the emissions of the overall operation. Additional improvements in other aspects like energy consumption are extremely difficult to achieve today as this parameter has already been highly optimized during the last two decades making in fact LAB a highly effective chemical in terms of energy requirements as well as on raw material consumption. The results of the first LCI of the new LAB technology indicate a reduction of CO process emissions to nearly 1/2 as compared to standard HF process as well as reduction in solid waste to 1/3 of the corresponding HF process. Important reductions have also been noticed on NOx emissions with the new technology.« less
Falk, Bryan; Reed, Robert N.
2015-01-01
Molecular approaches to prey identification are increasingly useful in elucidating predator–prey relationships, and we aimed to investigate the feasibility of these methods to document the species identities of prey consumed by invasive Burmese pythons in Florida. We were particularly interested in the diet of young snakes, because visual identification of prey from this size class has proven difficult. We successfully extracted DNA from the gastrointestinal contents of 43 young pythons, as well as from several control samples, and attempted amplification of DNA mini-barcodes, a 130-bp region of COX1. Using a PNA clamp to exclude python DNA, we found that prey DNA was not present in sufficient quality for amplification of this locus in 86% of our samples. All samples from the GI tracts of young pythons contained only hair, and the six samples we were able to identify to species were hispid cotton rats. This suggests that young Burmese pythons prey predominantly on small mammals and that prey diversity among snakes of this size class is low. We discuss prolonged gastrointestinal transit times and extreme gastric breakdown as possible causes of DNA degradation that limit the success of a molecular approach to prey identification in Burmese pythons
NASA Astrophysics Data System (ADS)
Tyler, Bonnie J.; Rangaranjan, Srinath; Möller, Jörg; Beumer, Andre'; Arlinghaus, Heinrich F.
2006-07-01
The diffusion of the anti-microbial chlorhexidine digluconate (CHG) has been studied in C. albicans biofilms by time-of-flight secondary-ion mass spectrometry (TOF-SIMS). C. albicans has been shown to become resistant to common anti-microbial agents, including CHG, when growing as a biofilm. Mass transport resistance within biofilms has commonly been suggested as a resistance mechanism, but measurement of transport for most anti-microbial agents in biofilms has proven extremely difficult because of the heterogeneity of the biofilms and the difficulty in detecting these agents within an intact biofilm. In this study, TOF-SIMS has been used to study the transport of CHG and glucose in a frozen hydrated biofilm. The TOF-SIMS images reveal a progression of CHG from the top of the biofilm to its base with time. Images suggest that there are channels within the biofilm and show preferential binding of CHG to cellular components of the biofilm. Additionally, both living and dead cells can be identified in the TOF-SIMS images by the sequestration of K + and the presence of cell markers. This study demonstrates that TOF-SIMS has the unique potential to simultaneously observe the presence of an antimicrobial agent, concentration of nutrients, and the viability of the cell population.
Assessment of geraniol-incorporated polymers to control Aedes albopictus (Diptera: culicidae)
Chuaycharoensuk, T.; Manguin, S.; Duvallet, G.; Chareonviriyaphap, T.
2012-01-01
Effective control of mosquito borne diseases has proven extremely difficult with both vector and pathogen remaining entrenched and expanding in many disease endemic areas. When lacking an effective vaccine, vector control methods targeting both larval habitats and adult mosquito populations remain the primary strategy for reducing risk. Aedes albopictus from Thailand was used as a reference baseline for evaluation of natural insecticides incorporated in polymer disks and pellets and tested both in laboratory and field conditions. In laboratory and field tests, the highest larval mortality was obtained with disks or pellets containing IKHC (Insect Killer Highly Concentrate) from Fulltec AG Company. This product is reputed to contain geraniol as an active ingredient. With pellets, high mortality of Ae. albopictus larvae (92%) was observed in presence of 1 g of pellets per 500 ml of water at day 1st, and the mortality was 100% at day 1st for larvae in presence of 5 or 10 g of pellets. Fulltec AG Company has not accepted to give us the exact composition of their IKHC product. Therefore, we cannot recommend it, but the principle of using monoterpenes like geraniol, incorporated into polymer disks or pellets as natural larvicide needs more attention as it could be considered as a powerful alternative in mosquito vector control. PMID:22910616
A Simple Flotation De-Linking Experiment for the Recycling of Paper
ERIC Educational Resources Information Center
Venditti, Richard A.
2004-01-01
A laboratory exercise for the flotation de-linking of wastepaper is described, which consists of disintegrating printed wastepaper in a blender and then removing the ink or toner contaminants by pumping air bubbles through suspension using an aquarium pump or other source of air bubbles. The exercise has proven extremely reliable and consistent in…
ERIC Educational Resources Information Center
Denham, A. R.
2015-01-01
There has been a steady rise in the support for games as learning environments. This support is largely based on the strong levels of engagement and motivation observed during gameplay. What has proven difficult is the ability to consistently design and develop learning games that are both engaging and educationally viable. Those in the game-based…
ERIC Educational Resources Information Center
Gustafsson, Jan-Eric
2013-01-01
In educational effectiveness research, it frequently has proven difficult to make credible inferences about cause and effect relations. The article first identifies the main categories of threats to valid causal inference from observational data, and discusses designs and analytic approaches which protect against them. With the use of data from 22…
Educating Men and Women about Sexual Harassment: An Exercise for Trainers and Teachers.
ERIC Educational Resources Information Center
Cooks, Leda M.
Sexual harassment has proven to be a difficult topic for men and women to discuss openly. The articulation of such experience cannot occur unless both can communicate about the nature of differences and the constraints of culture; men and women must forgo the assumption that they are speaking from the same situated experience. Although several…
Radionuclide diagnosis of splenic rupture in infectious mononucleosis
DOE Office of Scientific and Technical Information (OSTI.GOV)
Vezina, W.C.; Nicholson, R.L.; Cohen, P.
1984-06-01
Spontaneous splenic rupture is a rare but serious complication of infectious mononucleosis. Although radionuclide spleen imaging is a well accepted method for diagnosis of traumatic rupture, interpretation can be difficult in the setting of mononucleosis, as tears may be ill-defined and diagnosis hampered by inhomogeneous splenic uptake. Four proven cases of spontaneous rupture are presented, three of which illustrate these diagnostic problems.
The Use of Enhanced Bioremediation at the Savannah River Site to Remediate Pesticides and PCBs
DOE Office of Scientific and Technical Information (OSTI.GOV)
Beul, R.
2003-09-30
Enhanced bioremediation is quickly developing into an economical and viable technology for the remediation of contaminated soils. Until recently, chlorinated organic compounds have proven difficult to bioremediate. This article reviews the ongoing remediation occurring at the Chemicals, Metals, and Pesticides (CMP) Pits using windrow turners to facilitate microbial degradation of certain pesticides and PCBs.
Functional Concepts in Mental Retardation: Finding the Natural Essence of an Artificial Category
ERIC Educational Resources Information Center
Greenspan, Stephen
2006-01-01
Although there have always been people considered to have mental retardation (MR), the category has proven surprisingly difficult to define adequately. This is because it includes a subcategory of mild MR whose members are part of a larger population of marginally competent people, some of whom may be considered to have other forms of disability…
DOT National Transportation Integrated Search
1984-01-01
The construction and operation of an integrated mass transportation : system in the Washington Metropolitan Area has proven to be a : difficult task and will continue to be for the foreseeable future. The : administrative and financing structure of W...
Geoffrey J. Cary; Robert E. Keane; Robert H. Gardner; Sandra Lavorel; Mike D. Flannigan; Ian D. Davies; Chao Li; James M. Lenihan; T. Scott Rupp; Florent Mouillot
2006-01-01
The relative importance of variables in determining area burned is an important management consideration although gaining insights from existing empirical data has proven difficult. The purpose of this study was to compare the sensitivity of modeled area burned to environmental factors across a range of independently-developed landscape-fire-succession models. The...
Choosing to Major in Physics, or Not: Factors Affecting Undergraduate Decision Making
ERIC Educational Resources Information Center
Stiles-Clarke, Laura; MacLeod, Katarin
2016-01-01
For the past 40 years, there has been apprehension in North American society, and particularly in the scientific community, concerning the decline of interest and enrollment in science degree programs at the post-secondary level. This trend has proven very difficult to reverse. The purpose of this study was to explore why students at an Atlantic…
ERIC Educational Resources Information Center
Bergner, Yoav; Kerr, Deirdre; Pritchard, David E.
2015-01-01
Determining how learners use MOOCs effectively is critical to providing feedback to instructors, schools, and policy-makers on this highly scalable technology. However, drawing inferences about student learning outcomes in MOOCs has proven to be quite difficult due to large amounts of missing data (of various kinds) and to the diverse population…
Privatization and the allure of franchising: a Zambian feasibility study.
Fiedler, John L; Wight, Jonathan B
2003-01-01
Efforts to privatize portions of the health sector have proven more difficult to implement than had been anticipated previously. One common bottleneck encountered has been the traditional organizational structure of the private sector, with its plethora of independent, single physician practices. The atomistic nature of the sector has rendered many privatization efforts difficult, slow and costly-in terms of both organizational development and administration. In many parts of Africa, in particular, the shortages of human and social capital, and the fragile nature of legal institutions, undermine the appeal of privatization. The private sector is left with inefficiencies, high prices and costs, and a reduced effective demand. The result is the simultaneous existence of excess capacity and unmet need. One potential method to improve the efficiency of the private sector, and thereby enhance the likelihood of successful privatization, is to transfer managerial technology--via franchising--from models that have proven successful elsewhere. This paper presents a feasibility analysis of franchizing the successful Bolivian PROSALUD system's management package to Zambia. The assessment, based on PROSALUD's financial model, demonstrates that technology transfer requires careful adaptation to local conditions and, in this instance, would still require significant external assistance.
Design, implementation and migration of security systems as an extreme project.
DOE Office of Scientific and Technical Information (OSTI.GOV)
Scharmer, Carol; Trujillo, David
2010-08-01
Decision Trees, algorithms, software code, risk management, reports, plans, drawings, change control, presentations, and analysis - all useful tools and efforts but time consuming, resource intensive, and potentially costly for projects that have absolute schedule and budget constraints. What are necessary and prudent efforts when a customer calls with a major security problem that needs to be fixed with a proven, off-the-approval-list, multi-layered integrated system with high visibility and limited funding and expires at the end of the Fiscal Year? Whether driven by budget cycles, safety, or by management decree, many such projects begin with generic scopes and funding allocatedmore » based on a rapid management 'guestimate.' Then a Project Manager (PM) is assigned a project with a predefined and potentially limited scope, compressed schedule, and potentially insufficient funding. The PM is tasked to rapidly and cost effectively coordinate a requirements-based design, implementation, test, and turnover of a fully operational system to the customer, all while the customer is operating and maintaining an existing security system. Many project management manuals call this an impossible project that should not be attempted. However, security is serious business and the reality is that rapid deployment of proven systems via an 'Extreme Project' is sometimes necessary. Extreme Projects can be wildly successful but require a dedicated team of security professionals lead by an experienced project manager using a highly-tailored and agile project management process with management support at all levels, all combined with significant interface with the customer. This paper does not advocate such projects or condone eliminating the valuable analysis and project management techniques. Indeed, having worked on a well-planned project provides the basis for experienced team members to complete Extreme Projects. This paper does, however, provide insight into what it takes for projects to be successfully implemented and accepted when completed under extreme conditions.« less
Design implementation and migration of security systems as an extreme project.
DOE Office of Scientific and Technical Information (OSTI.GOV)
Scharmer, Carol
2010-10-01
Decision Trees, algorithms, software code, risk management, reports, plans, drawings, change control, presentations, and analysis - all useful tools and efforts but time consuming, resource intensive, and potentially costly for projects that have absolute schedule and budget constraints. What are necessary and prudent efforts when a customer calls with a major security problem that needs to be fixed with a proven, off-the-approval-list, multi-layered integrated system with high visibility and limited funding and expires at the end of the Fiscal Year? Whether driven by budget cycles, safety, or by management decree, many such projects begin with generic scopes and funding allocatedmore » based on a rapid management 'guestimate.' Then a Project Manager (PM) is assigned a project with a predefined and potentially limited scope, compressed schedule, and potentially insufficient funding. The PM is tasked to rapidly and cost effectively coordinate a requirements-based design, implementation, test, and turnover of a fully operational system to the customer, all while the customer is operating and maintaining an existing security system. Many project management manuals call this an impossible project that should not be attempted. However, security is serious business and the reality is that rapid deployment of proven systems via an 'Extreme Project' is sometimes necessary. Extreme Projects can be wildly successful but require a dedicated team of security professionals lead by an experienced project manager using a highly-tailored and agile project management process with management support at all levels, all combined with significant interface with the customer. This paper does not advocate such projects or condone eliminating the valuable analysis and project management techniques. Indeed, having worked on a well-planned project provides the basis for experienced team members to complete Extreme Projects. This paper does, however, provide insight into what it takes for projects to be successfully implemented and accepted when completed under extreme conditions.« less
Systemic nickel hypersensitivity and diet: myth or reality?
Pizzutelli, S
2011-02-01
Nickel is a very common metal contained in many everyday objects and is the leading cause of ACD (Allergic Contact Dermatitis). Nickel is present in most of the constituents of a normal diet, but some food groups are usually considered to be richer. However, the nickel content of specific food can vary widely, depending on many factors. Thus, the daily intake of nickel is also highly variable both among different populations and in a single individual, in different seasons and even in different days. Measuring precisely the daily intake of nickel from food and drinks is extremely difficult, if not impossible. The relationship between ACD and contact with nickel is undisputed and widely confirmed in literature. The situation is different for systemic nickel allergy syndrome (SNAS). The SNAS can have cutaneous signs and symptoms (Systemic Contact Dermatitis or SCD) or extracutaneous signs and symptoms (gastrointestinal, respiratory, neurological, etc.).The occurrence of SCD as a systemic reaction to the nickel normally assumed in the daily diet is very controversial. A rigorous demonstration of the relationship between SCD and nickel is extremely difficult. In particular, further and larger studies are needed to assess the reality and the prevalence of nickel urticaria. With respect to nickel-related gastrointestinal symptoms, as well as chronic fatigue syndrome, fibromyalgia, headache, recurring cold sores and recurrent infections in general, the data available in literature are not conclusive and the studies lack the support of clear, first-hand evidence. With respect to respiratory disorders, the role of food nickel and the effectiveness of a dietary treatment have been assumed but not proven. In fact, the usefullness of a therapeutic low-nickel diet is controversial: rare, if not exceptional, and limited to very sporadic cases of SCD. Additionally, the quantitative and qualitative composition of a low-nickel diet presents few certainties and many uncertainties. The low-nickel diets suggested in literature are highly variable, both in the extension of the restrictions and in their details--and the differences are not marginal. an evaluation of the data presented by medical literature about SNAS and its relationship with oral nickel does not allow to draw final conclusions. In the absence of genuine certainty we can only conclude that further and broader studies, more rigorously conducted, are needed.
2010-01-01
infection, or avascular necrosis is extremely difficult. Tibiocalcaneal fusion typically leaves a patient with a leg length discrepancy unless large bone...fractures. J Orthop Trauma 2004;18(5):265–70. 37. Dennison MG, Pool RD, Simonis RB, et al. Tibiocalcaneal fusion for avascular necrosis of the talus
Current thinking about acute compartment syndrome of the lower extremity
Shadgan, Babak; Menon, Matthew; Sanders, David; Berry, Gregg; Martin, Claude; Duffy, Paul; Stephen, David; O’Brien, Peter J.
2010-01-01
Acute compartment syndrome of the lower extremity is a clinical condition that, although uncommon, is seen fairly regularly in modern orthopedic practice. The pathophysiology of the disorder has been extensively described and is well known to physicians who care for patients with musculoskeletal injuries. The diagnosis, however, is often difficult to make. In this article, we review the clinical risk factors of acute compartment syndrome of the lower extremity, identify the current concepts of diagnosis and discuss appropriate treatment plans. We also describe the Canadian medicolegal environment in regard to compartment syndrome of the lower extremity. PMID:20858378
A tabular format of Pyle's ageing and sexing methods for landbirds
W.H. Sakai; C.J. Ralph
2002-01-01
We present a new method of summarizing Peter Pyle's (1997) ageing and sexing guide into a tabular format that has proven to be extremely useful for both novice and experienced banders. This format allows quick and accurate assessment by a bander to distinguish species, age, and sex criteria. Rapid and accurate processing are essential to the health of birds...
Tynan, Jennifer R; Schachar, Norman S; Marshall, Geoffrey B; Gray, Robin R
2005-02-01
Unicameral bone cysts of the pelvis are extremely rare. A 19-year old man presented with a pathologic fracture through a pelvic unicameral bone cyst. He was treated with computed tomography-guided percutaneous curettage, biopsy, and demineralized bone matrix injection. Treatment has proven successful in short-term follow-up.
Forensic odontology and the identification of human remains.
Halik, F J
1989-03-01
The forensic odontology discipline has proven to be another extremely important avenue of dentistry's service to mankind. Only the deeply committed, knowledgeable and skillful dental professional can provide this service and it cannot be duplicated. Scientific investigation leading to continual improvements in the techniques of identification as well as the other facts of forensic odontology are typical of dental professionalism and service.
Diffusion Monte Carlo calculations of Xenon and Krypton at High Pressure
NASA Astrophysics Data System (ADS)
Shulenburger, Luke; Mattsson, Thomas R.
2011-06-01
Ab initio calculations based on density functional theory (DFT) have proven a valuable tool in understanding the properties of materials at extreme conditions. However, there are entire classes of materials where the current limitations of DFT cast doubt upon the predictive power of the method. These include so called strongly correlated systems and materials where van der Waals forces are important. Diffusion Monte Carlo (DMC) can treat materials with a different class of approximations that have generally proven to be more accurate. The use of DMC together with DFT may therefore improve the predictive capability of the ab initio calculation of materials at extreme conditions. We present two examples of this approach. In the first we use DMC total energies to address the discrepancy between DFT and diamond anvil cell melt curves of Xe. In the second, DMC is used to address the choice of density functional used in calculations of the Kr hugoniot. Sandia National Laboratories is a multiprogram laboratory managed and operated by Sandia Corporation, a wholly owned subsidiary of Lockheed Martin Corporation, for the U.S. Department of Energy's National Nuclear Security Administration under Contract No. DE-AC04-94AL85000. Belonoshko et al. PRB 74, 054114 (2006).
ERIC Educational Resources Information Center
Anderson, Michael L.
2012-01-01
Spending on big-time college athletics is often justified on the grounds that athletic success attracts students and raises donations. Testing this claim has proven difficult because success is not randomly assigned. We exploit data on bookmaker spreads to estimate the probability of winning each game for college football teams. We then condition…
ERIC Educational Resources Information Center
Priode, Kimberly S.
2013-01-01
Gaining admission into pre-licensure nursing programs has proven to be quite difficult for the average college student. Topping the list of crucial priorities for many academic institutions is the retention of these nursing students. Yet, the reality is that many students decide not to complete their course of study for reasons other than academic…
ERIC Educational Resources Information Center
Lehr, Camilla A.; Johnson, David R.; Bremer, Christine D.; Cosio, Anna; Thompson, Megan
2004-01-01
This manual provides a synthesis of research-based dropout prevention and intervention and offers examples of interventions that show evidence of effectiveness. This has proven to be a difficult task because the intervention research on dropout and school completion that can be used to inform practice is incomplete (Dynarski & Gleason, 2002;…
Preventing Firefighter Exposure Hazards
2017-09-01
INTENTIONALLY LEFT BLANK i REPORT DOCUMENTATION PAGE Form Approved OMB No.0704-0188 Public reporting burden for this collection of information is... Form 298 (Rev.2-89) Prescribed by ANSI Std.239-18 ii THIS PAGE INTENTIONALLY LEFT BLANK iii Approved for public release. Distribution is...have been proven harmful to humans when they are in chemical form , it is difficult to measure their harmfulness when the chemicals are transformed
2009-01-01
The modified Brooke formula may not be effective in preventing all complications of fluid loading in all patients. The important concept is that if...addition to complicated mathematical computations [39]. They used their knowledge of expected fluid loss rates to devise a formula, based on trials of...burn resuscitations in order to prevent such a complication . This has proven to be a difficult task. The use of colloid has been examined in
ERIC Educational Resources Information Center
Teixeira, Julie Brill
2012-01-01
Since their inception, all schools of the Sacred Heart have been headed by nuns of the Religious of the Sacred Heart of Jesus [RSCJ]. As the years have passed, many RSCJ nuns have aged and retired leaving vacancies that have proven difficult to fill. In this qualitative study, the characteristics, commonalities, and personal motivations of Sacred…
ERIC Educational Resources Information Center
Riveros, Héctor G.
2012-01-01
The inquiry-based approach to learning has proven to be quite effective, since Socrates, but it is difficult to found good questions to induce reasoning. Many sources explain wrongly some experimental results, which can be used as discrepant events. Some use the breaking of a ruler with a newspaper to "show" that the atmospheric pressure…
ERIC Educational Resources Information Center
Shin, Nana; Vaughn, Brian E.; Kim, Mina; Krzysik, Lisa; Bost, Kelly K.; McBride, Brent; Santos, Antonio J.; Peceguina, Ines; Coppola, Gabrielle
2011-01-01
Achieving consensus on the definition and measurement of social competence (SC) for preschool children has proven difficult in the developmental sciences. We tested a hierarchical model in which SC is assumed to be a second-order latent variable by using longitudinal data (N = 345). We also tested the degree to which peer SC at Time 1 predicted…
ERIC Educational Resources Information Center
Dean, John F.
For a variety of reasons, collection care in Southeast Asia, especially in the northern regions, is fraught with many difficult challenges. Climates that are unfriendly to paper-based materials, poor economies, war, and civil unrest, are just a few of the reasons that librarians and archivists find it extremely difficult to ensure the survival of…
Effect of loudness on reaction time and response force in different motor tasks.
Jaśkowski, Piotr; Włodarczyk, Dariusz
2005-12-01
Van der Molen and Keuss, in 1979 and 1981, showed that paradoxically long reaction times occur with extremely strong auditory stimuli when the task is difficult, e.g., choice-by-location or Simon paradigm. It was argued that this paradoxical behavior of RT is due to active inhibition of an arousal-dependent bypassing mechanism to prevent false responses. As the peak force, i.e., maximal force exerted by participants on a response key, is considered to be related to immediate arousal, we predicted that for extremely loud stimuli and for difficult tasks, lengthening of RT should be associated with reduction of peak force. Moreover, these effects should be enhanced when emphasis is on accuracy rather than speed. Although the relation between RT and intensity depended on task difficulty, no increase in RT was found for the loudest tones. Moreover, peak force increased monotonically with loudness, showing no tendency to be suppressed for loudest tones and difficult tasks.
NASA Astrophysics Data System (ADS)
(Phil) Greenwood, Philip; Fister, Wolfgang; Kuhn, Nikolaus
2014-05-01
The invasive plant, Impatiens glandulifera (common English name: Himalayan Balsam), is now found in most temperate European countries, as well as across large parts of North America and on some Australasian islands. As a ruderal species, it favours damp, nutrient-rich soils that experience frequent natural disturbance, such as riparian zones. Its ability to out-compete native vegetation and tendency to suffer rapid dieback during cold weather has led to repeated speculation that it may promote soil erosion, particularly along riverbanks. Despite the strong implication, its ability to promote erosion has only recently been empirically proven during an investigation over one dieback and regrowth cycle along a small watercourse in northwest Switzerland. This presentation now benefits from additional results covering further dieback and regrowth cycles obtained from the same watercourse as above, and from a different river system in southwest UK. These additional results support the original conclusion that I. glandulifera promotes soil erosion along riverbanks and the riparian zone. Importantly, the equivalent ground surface retreat from each group of contaminated locations over the three dieback and regrowth cycles are comparable with erosion in regions where high magnitude events are often recorded. Given these very high erosion rates, albeit over three monitoring phases, it is hypothesised that I. glandulifera may act as a catalyst for repeat cycles of colonisation, dieback and extreme erosion. Aside from the deleterious effect of large quantities of nutrient-rich sediment entering into watercourses, high magnitude soil loss such as this could result in reach-scale sections of riverbank undergoing profound morphological changes and reduced structural stability. Dynamic modifications such as those could ultimately impede the ability of riverbanks to moderate stream flow and offer flood protection, as well as hamper the capacity of riparian zones to buffer and retain sediment and associated contaminants during their passage from terrestrial to aquatic environments. Given the dearth of effective intervention measures to halt, or even slow, the spread of I. glandulifera, the impact of extreme erosion driven by this invasive plant could eventually affect the ecohydromorphic functioning of whole river systems, thus making their management extremely difficult and complex.
Multi-Conformer Ensemble Docking to Difficult Protein Targets
Ellingson, Sally R.; Miao, Yinglong; Baudry, Jerome; ...
2014-09-08
We investigate large-scale ensemble docking using five proteins from the Directory of Useful Decoys (DUD, dud.docking.org) for which docking to crystal structures has proven difficult. Molecular dynamics trajectories are produced for each protein and an ensemble of representative conformational structures extracted from the trajectories. Docking calculations are performed on these selected simulation structures and ensemble-based enrichment factors compared with those obtained using docking in crystal structures of the same protein targets or random selection of compounds. We also found simulation-derived snapshots with improved enrichment factors that increased the chemical diversity of docking hits for four of the five selected proteins.more » A combination of all the docking results obtained from molecular dynamics simulation followed by selection of top-ranking compounds appears to be an effective strategy for increasing the number and diversity of hits when using docking to screen large libraries of chemicals against difficult protein targets.« less
NASA Astrophysics Data System (ADS)
Cucchi, Marco; Petitta, Marcello; Calmanti, Sandro
2016-04-01
High temperatures have an impact on the energy balance of any living organism and on the operational capabilities of critical infrastructures. Heat-wave indicators have been mainly developed with the aim of capturing the potential impacts on specific sectors (agriculture, health, wildfires, transport, power generation and distribution). However, the ability to capture the occurrence of extreme temperature events is an essential property of a multi-hazard extreme climate indicator. Aim of this study is to develop a standardized heat-wave indicator, that can be combined with other indices in order to describe multiple hazards in a single indicator. The proposed approach can be used in order to have a quantified indicator of the strenght of a certain extreme. As a matter of fact, extremes are usually distributed in exponential or exponential-exponential functions and it is difficult to quickly asses how strong was an extreme events considering only its magnitude. The proposed approach simplify the quantitative and qualitative communication of extreme magnitude
Bondability of ipê (Tabebuia spp.) wood using ambient-curing exterior wood adhesives
Daniel J. Yelle
2016-01-01
Ipê is an extremely difficult species to bond because of its high density, interlocking grain, and high volumetric swellingâshrinkage under prolonged wet conditions. Despite its difficulties, the wood is known to be extremely durable in exterior conditions because of its resistance to microbial and insect degradation. Therefore, investigating its bondability with...
The Extreme Ultraviolet Explorer science instruments development - Lessons learned
NASA Technical Reports Server (NTRS)
Malina, Roger F.; Battel, S.
1991-01-01
The science instruments development project for the Extreme Ultraviolet Explorer (EUVE) satellite is reviewed. Issues discussed include the philosophical basis of the program, the establishment of a tight development team, the approach to planning and phasing activities, the handling of the most difficult technical problems, and the assessment of the work done during the preimplemntation period of the project.
The attitudes of neonatal nurses towards extremely preterm infants.
Gallagher, Katie; Marlow, Neil; Edgley, Alison; Porock, Davina
2012-08-01
The paper is a report of a study of the attitudes of neonatal nurses towards extremely preterm infants. Alongside advancing survival at extremely preterm gestational ages, ethical debates concerning the provision of invasive care have proliferated in light of the high morbidity. Despite nurses being the healthcare professionals who work closest with the infant and their family, their potential influence is usually ignored when determining how parents come to decisions about future care for their extremely premature infant. A Q methodology was employed to explore the attitudes of neonatal nurses towards caring for extremely preterm infants. Data were collected between 2007 and 2008 and analysed using PQMethod and Card Content Analysis. Thirty-six nurses from six neonatal units in the United Kingdom participated. Although there was consensus around the professional role of the nurse, when faced with the complexities of neonatal nursing three distinguishing factors emerged: the importance of parental choice in decision-making, the belief that technology should be used to assess response to treatment, and the belief that healthcare professionals should undertake difficult decisions. Neonatal nurses report unexpected difficulties in upholding their professionally defined role through highly complex and ever varied decision-making processes. Recognition of individual attitudes to the care of extremely preterm infants and the role of the family in the face of difficult decisions should facilitate more open communication between the nurse and the parents and improve the experience of both the nurse and the family during these emotional situations. © 2011 Blackwell Publishing Ltd.
S-ProvFlow: provenance model and tools for scalable and adaptive analysis pipelines in geoscience.
NASA Astrophysics Data System (ADS)
Spinuso, A.; Mihajlovski, A.; Atkinson, M.; Filgueira, R.; Klampanos, I.; Sanchez, S.
2017-12-01
The reproducibility of scientific findings is essential to improve the quality and application of modern data-driven research. Delivering such reproducibility is challenging in the context of systems handling large data-streams with sophisticated computational methods. Similarly, the SKA (Square Kilometer Array) will collect an unprecedented volume of radio-wave signals that will have to be reduced and transformed into derived products, with impact on space-weather research. This highlights the importance of having cross-disciplines mechanisms at the producer's side that rely on usable lineage data to support validation and traceability of the new artifacts. To be informative, provenance has to describe each methods' abstractions and their implementation as mappings onto distributed platforms and their concurrent execution, capturing relevant internal dependencies at runtime. Producers and intelligent toolsets should be able to exploit the produced provenance, steering real-time monitoring activities and inferring adaptations of methods at runtime.We present a model of provenance (S-PROV) that extends W3C PROV and ProvONE, broadening coverage of provenance to aspects related to distribution, scale-up and steering of stateful streaming operators in analytic pipelines. This is supported by a technical framework for tuneable and actionable lineage, ensuring its relevance to the users' interests, fostering its rapid exploitation to facilitate research practices. By applying concepts such as provenance typing and profiling, users define rules to capture common provenance patterns and activate selective controls based on domain-metadata. The traces are recorded in a document-store with index optimisation and a web API serves advanced interactive tools (S-ProvFlow, https://github.com/KNMI/s-provenance). These allow different classes of consumers to rapidly explore the provenance data. The system, which contributes to the SKA-Link initiative, within technology and knowledge transfer events, will be discussed in the context of an existing data-intensive service for seismology (VERCE), and the newly funded project DARE - Delivering Agile Research Excellence. A generic solution for extreme data and methods in geosciences that domain experts can understand, change and use effectively.
2015-01-01
precluded because they are expensive to produce and unstable in all but the most optimized conditions. Aptamers have provided a popular alternative...has proven difficult (Song, Lee, and Ban 2012). Aptamers , however, do include their own challenges as their isolation through selection pro- cesses are...single-chain antibodies contain the same recognition properties of standard antibodies but are much smaller with a stability similar to aptamers
Enterocutaneous Fistula: Proven Strategies and Updates
Gribovskaja-Rupp, Irena; Melton, Genevieve B.
2016-01-01
Management of enterocutaneous fistula represents one of the most protracted and difficult problems in colorectal surgery with substantial morbidity and mortality rates. This article summarizes the current classification systems and successful management protocols, provides an in-depth review of fluid resuscitation, sepsis control, nutrition management, medication management of output quantity, wound care, nonoperative intervention measures, operative timeline, and considerations, and discusses special considerations such as inflammatory bowel disease and enteroatmospheric fistula. PMID:27247538
Sara R. Morris; Erica M. Turner; David A. Liebner; Amanda M. Larracuente; H. David Sheets
2005-01-01
One measure of the importance of a stopover site is the length of time that migrants spend at an area, however measuring the time birds spend at a stopover site has proven difficult. Most banding studies have presented only minimum length of stopover, based on the difference between initial capture and final recapture of birds that are captured more than once. Cormack-...
Use of Severity of Illness Indexes for Assessing Health Care Provider Performance
1985-07-01
Exclusive reliance on manual selection of the inpatient records would have proven difficult and time consuming. Appendix B contains correspondence...presence of mortalities or complications following surgery. Results obtained from the two-fold PASBA screen and manual selection process represent a...information provided include the last four numbers of each patient’s social security number, register number, procedure and occurrence found. A manual
Quality versus quantity: The complexities of quality of life determinations for neonatal nurses.
Green, Janet; Darbyshire, Philip; Adams, Anne; Jackson, Debra
2017-11-01
The ability to save the life of an extremely premature baby has increased substantially over the last decade. This survival, however, can be associated with unfavourable outcomes for both baby and family. Questions are now being asked about quality of life for survivors of extreme prematurity. Quality of life is rightly deemed to be an important consideration in high technology neonatal care; yet, it is notoriously difficult to determine or predict. How does one define and operationalise what is considered to be in the best interest of a surviving extremely premature baby, especially when the full extent of the outcomes might not be known for several years? The research investigates the caregiving dilemmas often faced by neonatal nurses when caring for extremely premature babies. This article explores the issues arising for neonatal nurses when they considered the philosophical and ethical questions about quality of life in babies ≤24 weeks gestation. Data were collected via a questionnaire to Australian neonatal nurses and semi-structured interviews with 24 neonatal nurses in New South Wales, Australia. Ethical considerations: Ethical processes and procedures have been adhered to by the researchers. A qualitative approach was used to analyse the data. The theme 'difficult choices' was generated which comprised three sub-themes: 'damaged through survival', 'the importance of the brain' and 'families are important'. The results show that neonatal nurses believed that quality of life was an important consideration; yet they experienced significant inner conflict and uncertainty when asked to define or suggest specific elements of quality of life, or to suggest how it might be determined. It was even more difficult for the nurses to say when an extremely premature baby's life possessed quality. Their previous clinical and personal experiences led the nurses to believe that the quality of the family's life was important, and possibly more so than the quality of life of the surviving baby. This finding contrasts markedly with much of the existing literature in this field. Quality of life for extremely premature babies was an important consideration for neonatal nurses; however, they experienced difficulty deciding how to operationalise such considerations in their everyday clinical practice.
Gadabanahalli, Karthik; Belaval, Vinay V; Bhat, Venkatraman; Gorur, Imran M
2015-04-01
Primary extraskeletal myxoid chondrosarcoma of the pulmonary arteries is a very rare entity. Multimodality imaging reports on this entity are few. Myxoid chondrosarcoma is characterized by chondroid and neurogenic differentiation in extraskeletal locations. These tumours represent fewer than 2.5% of all soft-tissue sarcomas, and are most commonly found in the lower extremities, limb girdles, distal extremities and trunk. We report an unusual case of a 31-year old man with histopathologically proven extraskeletal myxoid chondrosarcoma of the pulmonary arteries mimicking acute pulmonary thromboembolism. © The Author 2015. Published by Oxford University Press on behalf of the European Association for Cardio-Thoracic Surgery. All rights reserved.
Influence of Body Weight on Bone Mass, Architecture, and Turnover
Iwaniec, Urszula T.; Turner, Russell T.
2016-01-01
Weight-dependent loading of the skeleton plays an important role in establishing and maintaining bone mass and strength. This review focuses on mechanical signaling induced by body weight as an essential mechanism for maintaining bone health. In addition, the skeletal effects of deviation from normal weight are discussed. The magnitude of mechanical strain experienced by bone during normal activities is remarkably similar among vertebrates, regardless of size, supporting the existence of a conserved regulatory mechanism, or mechanostat, that senses mechanical strain. The mechanostat functions as an adaptive mechanism to optimize bone mass and architecture based on prevailing mechanical strain. Changes in weight, due to altered mass, weightlessness (spaceflight), and hypergravity (modeled by centrifugation), induce an adaptive skeletal response. However, the precise mechanisms governing the skeletal response are incompletely understood. Furthermore, establishing whether the adaptive response maintains the mechanical competence of the skeleton has proven difficult, necessitating development of surrogate measures of bone quality. The mechanostat is influenced by regulatory inputs to facilitate non-mechanical functions of the skeleton, such as mineral homeostasis, as well as hormones and energy/nutrient availability that support bone metabolism. While the skeleton is very capable of adapting to changes in weight, the mechanostat has limits. At the limits, extreme deviations from normal weight and body composition are associated with impaired optimization of bone strength to prevailing body size. PMID:27352896
UAS Photogrammetry for Rapid Response Characterization of Subaerial Coastal Change
NASA Astrophysics Data System (ADS)
Do, C.; Anarde, K.; Figlus, J.; Prouse, W.; Bedient, P. B.
2016-12-01
Unmanned aerial systems (UASs) provide an exciting new platform for rapid response measurement of subaerial coastal change. Here we validate the use of a coupled hobbyist UAS and optical photogrammetry framework for high-resolution mapping of portions of a low-lying barrier island along the Texas Gulf Coast. A DJI Phantom 3 Professional was used to capture 2D nadir images of the foreshore and back-beach environments containing both vegetated and non-vegetated features. The images were georeferenced using ground-truth markers surveyed via real-time kinematic (RTK) GPS and were then imported into Agisoft Photoscan, a photo-processing software, to generate 3D point clouds and digital elevation maps (DEMs). The georeferenced elevation models were then compared to RTK measurements to evaluate accuracy and precision. Thus far, DEMs derived from UAS photogrammetry show centimeter resolution for renderings of non-vegetated landforms. High-resolution renderings of vegetated and back-barrier regions have proven more difficult due to interstitial wetlands (surface reflectance) and uneven terrain for GPS backpack surveys. In addition to producing high-quality models, UAS photogrammetry has demonstrated to be more time-efficient than traditional mapping methods, making it advantageous for rapid response deployments. This study is part of a larger effort to relate field measurements of storm hydrodynamics to subaerial evidence of geomorphic change to better understand barrier island response to extreme storms.
NASA Astrophysics Data System (ADS)
Bory, A. J.; Skonieczny, C.; Bout-Roumazeilles, V.; Grousset, F. E.; Biscaye, P. E.
2011-12-01
Dust records retrieved from ice and sediment cores represent some of our most valuable evidence for modifications of atmospheric circulation on various times scales over the last few Pleistocene glacial and interglacial climate cycles. These data also contribute to the documentation of changes in continental paleo-environments (e.g., changes in aridity), changes in iron inputs to the ocean, as well as changes in the hydrological cycle. Interpreting ice and sediment-core dust records, and using them for modelling purposes, requires firstly a good understanding of the dust provenance and its possible temporal variability. Specific intrinsic tracers such as clay mineralogy, major and trace elements, and radiogenic isotopes (strontium, neodymium, lead) have been used for this purpose, with variable effectiveness. One difficulty lies in the fact that these measurements require significant amount of mineral particles and can thus only be obtained at low temporal resolution, either because of the low dust concentration in ice cores or because of the low mass accumulation rates and bioturbation in marine sediments. As a result, dust samples extracted from ice and sediment cores for provenance investigation average long periods of time and may reflect mixtures from various source areas, complicating the interpretation of the data. Still, provenance tracers (clay mineralogy and Sr-Nd isotopes in particular) made possible for instance the discrimination of which continents provided most of the dust deposited in remote locations such as Greenland and Antarctica during the dusty glacial stages. The locations of the contributing source areas, however, were not precisely identified. During the low-dust, interglacial periods, provenance has proven more difficult to establish unambiguously, even at broad (i.e., continental) geographic scales. In other aeolian deposits, such as Asian loess or marine sediments off West Africa, the provenance of the dust is still poorly constrained, despite the fact that these archives are located close to the highest dust-emission areas in the world. Characterization of dust provenance (using mineralogical and isotopic fingerprints) at present, which can be achieved at much higher resolution and benefit from remote sensing data and well-constrained GMC outputs, may provide valuable clues for our understanding of dust provenance in paleoclimate records. We review some investigations carried out in Greenland and Antarctica over the last decade, and present new results from the West African margin. We discuss the extent to which these present-day time series may help us calibrating our paleo-dust provenance proxies, and improving our understanding of dust provenance in paleoclimate records.
Difficult to control atopic dermatitis
2013-01-01
Difficult to control atopic dermatitis (AD) presents a therapeutic challenge and often requires combinations of topical and systemic treatment. Anti-inflammatory treatment of severe AD most commonly includes topical glucocorticosteroids and topical calcineurin antagonists used for exacerbation management and more recently for proactive therapy in selected cases. Topical corticosteroids remain the mainstay of therapy, the topical calcineurin inhibitors tacrolimus and pimecrolimus are preferred in certain locations. Systemic anti-inflammatory treatment is an option for severe refractory cases. Microbial colonization and superinfection contribute to disease exacerbation and thus justify additional antimicrobial / antiseptic treatment. Systemic antihistamines (H1) may relieve pruritus but do not have sufficient effect on eczema. Adjuvant therapy includes UV irradiation preferably of UVA1 wavelength. “Eczema school” educational programs have been proven to be helpful. PMID:23663504
Titian: Data Provenance Support in Spark
Interlandi, Matteo; Shah, Kshitij; Tetali, Sai Deep; Gulzar, Muhammad Ali; Yoo, Seunghyun; Kim, Miryung; Millstein, Todd; Condie, Tyson
2015-01-01
Debugging data processing logic in Data-Intensive Scalable Computing (DISC) systems is a difficult and time consuming effort. Today’s DISC systems offer very little tooling for debugging programs, and as a result programmers spend countless hours collecting evidence (e.g., from log files) and performing trial and error debugging. To aid this effort, we built Titian, a library that enables data provenance—tracking data through transformations—in Apache Spark. Data scientists using the Titian Spark extension will be able to quickly identify the input data at the root cause of a potential bug or outlier result. Titian is built directly into the Spark platform and offers data provenance support at interactive speeds—orders-of-magnitude faster than alternative solutions—while minimally impacting Spark job performance; observed overheads for capturing data lineage rarely exceed 30% above the baseline job execution time. PMID:26726305
Payne, Isaac; Grimm, Leander M.
2017-01-01
Paradoxical puborectalis contraction (PPC) and increased perineal descent (IPD) are subclasses of obstructive defecation. Often these conditions coexist, which can make the evaluation, workup, and treatment difficult. After a thorough history and examination, workup begins with utilization of proven diagnostic modalities such as cinedefecography and anal manometry. Advancements in technology have increased the surgeon's diagnostic armamentarium. Biofeedback and pelvic floor therapy have proven efficacy for both conditions as first-line treatment. In circumstances where PPC is refractory to biofeedback therapy, botulinum toxin injection is recommended. Historically, pelvic floor repair has been met with suboptimal results. In IPD, surgical therapy now is directed toward the potentially attendant abnormalities such as rectoanal intussusception and rectal prolapse. When these associated abnormalities are not present, an ostomy should be considered in patients with IPD as well as medically refractory PPC. PMID:28144209
ERIC Educational Resources Information Center
Holcomb, Betty
2018-01-01
Investments in quality child care and full-day pre-K more than pay for themselves, especially in tough economic times. They are proven strategies for reversing the growing income inequality in New York State, the most extreme in the nation by giving every child the resources to become successful wage earners. New York State leaders must build…
The parser generator as a general purpose tool
NASA Technical Reports Server (NTRS)
Noonan, R. E.; Collins, W. R.
1985-01-01
The parser generator has proven to be an extremely useful, general purpose tool. It can be used effectively by programmers having only a knowledge of grammars and no training at all in the theory of formal parsing. Some of the application areas for which a table-driven parser can be used include interactive, query languages, menu systems, translators, and programming support tools. Each of these is illustrated by an example grammar.
An Investigation of Wave Impact Duration in High-Speed Planing Craft in Rough Water
2014-04-01
10 Figure 9. CCD’s CObIA cRIO Data Acquisition System.............................................................11 Figure 10...environment. CCD’s CObIA system shown in Figure 9, based on National Instruments Compact RIO, has proven itself suitable for seakeeping measurements in...even the most extreme conditions. Figure 9. CCD’s CObIA cRIO Data Acquisition System Personal computers have also improved, allowing engineers to
The U.S. Air Force Transformation Flight Plan
2003-11-01
at Buckley Air Force Base, Colorado. Reserve Associate and Active Associate units have proven that this concept works and benef its the Active and...munitions manufactured from nano-particles, whose virtually all-surface structure yields unprecedented “burn-rates” (extreme explosiveness), promise far...systems for a common operating system, and a suite of remotely operated sensors, weapons, and robotics . Also included are a group of non-lethal weapon
A case of keratosis lichenoid chronica.
Baczewski, Natasha; Albano, Brian
2012-01-01
Keratosis lichenoid chronica is a rare dermatologic anomaly believed to be a variant of lichen planus. It presents as violaceous, nodular lesions usually on the dorsal aspects of the extremities and the trunk. The disease is refractory to treatment although psoralen ultraviolet A therapy and oral retinoids have been proven useful in some cases. Here we present the case of a 58-year-old male diagnosed with keratosis lichenoid chronica.
Distant Galaxy Clusters Hosting Extreme Central Galaxies
NASA Astrophysics Data System (ADS)
McDonald, Michael
2014-09-01
The recently-discovered Phoenix cluster harbors the most star-forming central cluster galaxy of any cluster in the known Universe, by nearly a factor of 10. This extreme system appears to be fulfilling early cooling flow predictions, although the lack of similar systems makes any interpretation difficult. In an attempt to find other "Phoenix-like" clusters, we have cross-correlated archival all-sky surveys (in which Phoenix was detected) and isolated 4 similarly-extreme systems which are also coincident in position and redshift with an overdensity of red galaxies. We propose here to obtain Chandra observations of these extreme, Phoenix-like systems, in order to confirm them as relaxed, rapidly-cooling galaxy clusters.
Río Tinto: A Geochemical and Mineralogical Terrestrial Analogue of Mars
NASA Astrophysics Data System (ADS)
Amils, Ricardo; Fernández-Remolar, David
2014-09-01
The geomicrobiological characterization of the water column and sediments of Río Tinto (Huelva, Southwestern Spain) have proven the importance of the iron and the sulfur cycles, not only in generating the extreme conditions of the habitat (low pH, high concentration of toxic heavy metals), but also in maintaining the high level of microbial diversity detected in the basin. It has been proven that the extreme acidic conditions of Río Tinto basin are not the product of 5000 years of mining activity in the area, but the consequence of an active underground bioreactor that obtains its energy from the massive sulfidic minerals existing in the Iberian Pyrite Belt. Two drilling projects, MARTE (Mars Astrobiology Research and Technology Experiment) (2003-2006) and IPBSL (Iberian Pyrite Belt Subsurface Life Detection) (2011-2015), were developed and carried out to provide evidence of subsurface microbial activity and the potential resources that support these activities. The reduced substrates and the oxidants that drive the system appear to come from the rock matrix. These resources need only groundwater to launch diverse microbial metabolisms. The similarities between the vast sulfate and iron oxide deposits on Mars and the main sulfide bioleaching products found in the Tinto basin have given Río Tinto the status of a geochemical and mineralogical Mars terrestrial analogue.
To the fringe and back: Violent extremism and the psychology of deviance.
Kruglanski, Arie W; Jasko, Katarzyna; Chernikova, Marina; Dugas, Michelle; Webber, David
2017-04-01
We outline a general psychological theory of extremism and apply it to the special case of violent extremism (VE). Extremism is defined as motivated deviance from general behavioral norms and is assumed to stem from a shift from a balanced satisfaction of basic human needs afforded by moderation to a motivational imbalance wherein a given need dominates the others. Because motivational imbalance is difficult to sustain, only few individuals do, rendering extreme behavior relatively rare, hence deviant. Thus, individual dynamics translate into social patterns wherein majorities of individuals practice moderation, whereas extremism is the province of the few. Both extremism and moderation require the ability to successfully carry out the activities that these demand. Ability is partially determined by the activities' difficulty, controllable in part by external agents who promote or oppose extremism. Application of this general framework to VE identifies the specific need that animates it and offers broad guidelines for addressing this pernicious phenomenon. (PsycINFO Database Record (c) 2017 APA, all rights reserved).
1988-05-25
reverse if necessary and identify by block numoer) FIELD GROUP SUB-GROUP phylogeny; evolution PJ 06 103 Key Words - archaebacteria ;eubacteria...branching representatives of the eubacterial kingdom (yet known) are, without exception, thermophilic, which is also the 6ra case for the archaebacterial... kingdom . A bacterium isolated from the Red Sea by Prof. Karl Stetter has proven to be difficult to grow in the quantities required for RNA sequencing
Role of APOE Isforms in the Pathogenesis of TBI Induced Alzheimer’s Disease
2014-10-01
the inheritance of APOe4 is the only proven genetic risk factor for sporadic Alzheimer disease (AD). Importantly, TBI is a risk factor for the...mice on human APOE genetic background were exceptionally difficult to generate. We are considering changes in the genotype of those particular groups...mediated through ABCA1. 2 Keywords Traumatic brain injury, APOE isoforms, ABCA1, Alzheimer disease, APPmice, amyloid beta, axonal injury, inflamma
Decision Making in the Submarine Information Architecture
2012-12-15
proven to be successful for the watch section in the past. Collectively these predilections build up over time like a collective Kalman filter . Watch...especially hard to predict and resources are strained , the planning horizon is likely to be much shorter. c. It is difficult to gauge how well these...becomes an effective filter for information and variety as long as the strategies are successful. These strategies become basins of stability for watch
2010-04-01
this heterogeneity, for the purpose of predicting water flow and reactive transport behavior at the field scale, has proven quite difficult. This...potential (soil water pressure) at the outlet and at offset points in response injections at different inlet pressure heads. 13 Task 2: Development...preferential pathways (Wu et al., 1993). A viable solution to this problem is to supply water under tension using an inflatable borehole
The use of historical information for regional frequency analysis of extreme skew surge
NASA Astrophysics Data System (ADS)
Frau, Roberto; Andreewsky, Marc; Bernardara, Pietro
2018-03-01
The design of effective coastal protections requires an adequate estimation of the annual occurrence probability of rare events associated with a return period up to 103 years. Regional frequency analysis (RFA) has been proven to be an applicable way to estimate extreme events by sorting regional data into large and spatially distributed datasets. Nowadays, historical data are available to provide new insight on past event estimation. The utilisation of historical information would increase the precision and the reliability of regional extreme's quantile estimation. However, historical data are from significant extreme events that are not recorded by tide gauge. They usually look like isolated data and they are different from continuous data from systematic measurements of tide gauges. This makes the definition of the duration of our observations period complicated. However, the duration of the observation period is crucial for the frequency estimation of extreme occurrences. For this reason, we introduced here the concept of credible duration
. The proposed RFA method (hereinafter referenced as FAB, from the name of the authors) allows the use of historical data together with systematic data, which is a result of the use of the credible duration concept.
Provenance in Data Interoperability for Multi-Sensor Intercomparison
NASA Technical Reports Server (NTRS)
Lynnes, Chris; Leptoukh, Greg; Berrick, Steve; Shen, Suhung; Prados, Ana; Fox, Peter; Yang, Wenli; Min, Min; Holloway, Dan; Enloe, Yonsook
2008-01-01
As our inventory of Earth science data sets grows, the ability to compare, merge and fuse multiple datasets grows in importance. This requires a deeper data interoperability than we have now. Efforts such as Open Geospatial Consortium and OPeNDAP (Open-source Project for a Network Data Access Protocol) have broken down format barriers to interoperability; the next challenge is the semantic aspects of the data. Consider the issues when satellite data are merged, cross-calibrated, validated, inter-compared and fused. We must match up data sets that are related, yet different in significant ways: the phenomenon being measured, measurement technique, location in space-time or quality of the measurements. If subtle distinctions between similar measurements are not clear to the user, results can be meaningless or lead to an incorrect interpretation of the data. Most of these distinctions trace to how the data came to be: sensors, processing and quality assessment. For example, monthly averages of satellite-based aerosol measurements often show significant discrepancies, which might be due to differences in spatio- temporal aggregation, sampling issues, sensor biases, algorithm differences or calibration issues. Provenance information must be captured in a semantic framework that allows data inter-use tools to incorporate it and aid in the intervention of comparison or merged products. Semantic web technology allows us to encode our knowledge of measurement characteristics, phenomena measured, space-time representation, and data quality attributes in a well-structured, machine-readable ontology and rulesets. An analysis tool can use this knowledge to show users the provenance-related distrintions between two variables, advising on options for further data processing and analysis. An additional problem for workflows distributed across heterogeneous systems is retrieval and transport of provenance. Provenance may be either embedded within the data payload, or transmitted from server to client in an out-of-band mechanism. The out of band mechanism is more flexible in the richness of provenance information that can be accomodated, but it relies on a persistent framework and can be difficult for legacy clients to use. We are prototyping the embedded model, incorporating provenance within metadata objects in the data payload. Thus, it always remains with the data. The downside is a limit to the size of provenance metadata that we can include, an issue that will eventually need resolution to encompass the richness of provenance information required for daata intercomparison and merging.
Identifying Opportunities for Vertical Integration of Biochemistry and Clinical Medicine.
Wendelberger, Karen J.; Burke, Rebecca; Haas, Arthur L.; Harenwattananon, Marisa; Simpson, Deborah
1998-01-01
Objectives: Retention of basic science knowledge, as judged by National Board of Medical Examiners' (NBME) data, suffers due to lack of apparent relevance and isolation of instruction from clinical application, especially in biochemistry. However, the literature reveals no systematic process for identifying key biochemical concepts and associated clinical conditions. This study systematically identified difficult biochemical concepts and their common clinical conditions as a critical step towards enhancing relevance and retention of biochemistry.Methods: A multi-step/ multiple stakeholder process was used to: (1) identify important biochemistry concepts; (2) determine students' perceptions of concept difficulty; (3) assess biochemistry faculty, student, and clinical teaching scholars' perceived relevance of identified concepts; and (4) identify associated common clinical conditions for relevant and difficult concepts. Surveys and a modified Delphi process were used to gather data, subsequently analyzed using SPSS for Windows.Results: Sixteen key biochemical concepts were identified. Second year medical students rated 14/16 concepts as extremely difficult while fourth year students rated nine concepts as moderately to extremely difficult. On average, each teaching scholar generated common clinical conditions for 6.2 of the 16 concepts, yielding a set of seven critical concepts and associated clinical conditions.Conclusions: Key stakeholders in the instructional process struggle to identify biochemistry concepts that are critical, difficult to learn and associated with common clinical conditions. However, through a systematic process beginning with identification of concepts and associated clinical conditions, relevance of basic science instruction can be enhanced.
Patients whom neurologists find difficult to help
Carson, A; Stone, J; Warlow, C; Sharpe, M
2004-01-01
Objective: To test the hypothesis that patients whose symptoms were less explained by organic disease would be perceived as more difficult to help. Methods: In a consecutive series of 300 new neurology outpatients, neurologists indicated on four point Likert-type scales how "difficult to help" they found the patient and to what extent the patient's symptoms were explained by organic disease. The patients' demographics, health status, number of somatic symptoms, and mental state were also assessed. Results: The neurologists rated 143 patients (48%) as "not at all difficult" to help, 111 (37%) as "somewhat difficult", 27 (9%) as "very difficult", and 18 (6%) as "extremely difficult". A logistic regression model was constructed and the hypothesis that patients whose symptoms were less explained by organic disease would be perceived as more difficult to help was supported. The only other measured variable that contributed to perceived difficulty was physical disability, but it explained only a small amount of the variance. Conclusions: Neurologists find patients whose symptoms are not explained by organic disease more difficult to help than their other patients. PMID:15548505
A fire danger rating system for Hawaii
Robert E. Burgan; Francis M. Fujioka; George H. Hirata
1974-01-01
Extremes in rainfall on the Hawaiian Islands make it difficult to judge forest fire danger conditions. The use of an automatic data collection and computer processing system helps to monitor the problem.
DOE Office of Scientific and Technical Information (OSTI.GOV)
Carothers, Christopher D.; Meredith, Jeremy S.; Blanco, Marc
Performance modeling of extreme-scale applications on accurate representations of potential architectures is critical for designing next generation supercomputing systems because it is impractical to construct prototype systems at scale with new network hardware in order to explore designs and policies. However, these simulations often rely on static application traces that can be difficult to work with because of their size and lack of flexibility to extend or scale up without rerunning the original application. To address this problem, we have created a new technique for generating scalable, flexible workloads from real applications, we have implemented a prototype, called Durango, thatmore » combines a proven analytical performance modeling language, Aspen, with the massively parallel HPC network modeling capabilities of the CODES framework.Our models are compact, parameterized and representative of real applications with computation events. They are not resource intensive to create and are portable across simulator environments. We demonstrate the utility of Durango by simulating the LULESH application in the CODES simulation environment on several topologies and show that Durango is practical to use for simulation without loss of fidelity, as quantified by simulation metrics. During our validation of Durango's generated communication model of LULESH, we found that the original LULESH miniapp code had a latent bug where the MPI_Waitall operation was used incorrectly. This finding underscores the potential need for a tool such as Durango, beyond its benefits for flexible workload generation and modeling.Additionally, we demonstrate the efficacy of Durango's direct integration approach, which links Aspen into CODES as part of the running network simulation model. Here, Aspen generates the application-level computation timing events, which in turn drive the start of a network communication phase. Results show that Durango's performance scales well when executing both torus and dragonfly network models on up to 4K Blue Gene/Q nodes using 32K MPI ranks, Durango also avoids the overheads and complexities associated with extreme-scale trace files.« less
Ullrich, Sophie R.; González, Carolina; Poehlein, Anja; Tischler, Judith S.; Daniel, Rolf; Schlömann, Michael; Holmes, David S.; Mühling, Martin
2016-01-01
Acid mine drainage (AMD), associated with active and abandoned mining sites, is a habitat for acidophilic microorganisms that gain energy from the oxidation of reduced sulfur compounds and ferrous iron and that thrive at pH below 4. Members of the recently proposed genus “Ferrovum” are the first acidophilic iron oxidizers to be described within the Betaproteobacteria. Although they have been detected as typical community members in AMD habitats worldwide, knowledge of their phylogenetic and metabolic diversity is scarce. Genomics approaches appear to be most promising in addressing this lacuna since isolation and cultivation of “Ferrovum” has proven to be extremely difficult and has so far only been successful for the designated type strain “Ferrovum myxofaciens” P3G. In this study, the genomes of two novel strains of “Ferrovum” (PN-J185 and Z-31) derived from water samples of a mine water treatment plant were sequenced. These genomes were compared with those of “Ferrovum” sp. JA12 that also originated from the mine water treatment plant, and of the type strain (P3G). Phylogenomic scrutiny suggests that the four strains represent three “Ferrovum” species that cluster in two groups (1 and 2). Comprehensive analysis of their predicted metabolic pathways revealed that these groups harbor characteristic metabolic profiles, notably with respect to motility, chemotaxis, nitrogen metabolism, biofilm formation and their potential strategies to cope with the acidic environment. For example, while the “F. myxofaciens” strains (group 1) appear to be motile and diazotrophic, the non-motile group 2 strains have the predicted potential to use a greater variety of fixed nitrogen sources. Furthermore, analysis of their genome synteny provides first insights into their genome evolution, suggesting that horizontal gene transfer and genome reduction in the group 2 strains by loss of genes encoding complete metabolic pathways or physiological features contributed to the observed diversification. PMID:27303384
Study of an astronomical extreme ultraviolet rocket spectrometer for use on shuttle missions
NASA Technical Reports Server (NTRS)
Bowyer, C. S.
1977-01-01
The adaptation of an extreme ultraviolet astronomy rocket payload for flight on the shuttle was studied. A sample payload for determining integration and flight procedures for experiments which may typically be flown on shuttle missions was provided. The electrical, mechanical, thermal, and operational interface requirements between the payload and the orbiter were examined. Of particular concern was establishing a baseline payload accommodation which utilizes proven common hardware for electrical, data, command, and possibly real time monitoring functions. The instrument integration and checkout procedures necessary to assure satisfactory in-orbit instrument performance were defined and those procedures which can be implemented in such a way as to minimize their impact on orbiter integration schedules were identified.
Biological Effects of Short, High-Level Exposure to Gases: Nitrogen Oxides.
1980-07-01
damage. Proven effects are mainly on the respiratory tract. Intense exposures result in death, hospitalization with recovery, or severe responses not...and up, for single exposures of a few minutes up to 1 hour. At the other extreme the threshold of measurable respiratory impairment in volunteers is...reversible or irreversible respiratory impairment by NOx on oxygen sufficiency and,hence, physical and mental capacity has not been measured in man, but
NASA Astrophysics Data System (ADS)
Lazoglou, Georgia; Anagnostopoulou, Christina; Tolika, Konstantia; Kolyva-Machera, Fotini
2018-04-01
The increasing trend of the intensity and frequency of temperature and precipitation extremes during the past decades has substantial environmental and socioeconomic impacts. Thus, the objective of the present study is the comparison of several statistical methods of the extreme value theory (EVT) in order to identify which is the most appropriate to analyze the behavior of the extreme precipitation, and high and low temperature events, in the Mediterranean region. The extremes choice was made using both the block maxima and the peaks over threshold (POT) technique and as a consequence both the generalized extreme value (GEV) and generalized Pareto distributions (GPDs) were used to fit them. The results were compared, in order to select the most appropriate distribution for extremes characterization. Moreover, this study evaluates the maximum likelihood estimation, the L-moments and the Bayesian method, based on both graphical and statistical goodness-of-fit tests. It was revealed that the GPD can characterize accurately both precipitation and temperature extreme events. Additionally, GEV distribution with the Bayesian method is proven to be appropriate especially for the greatest values of extremes. Another important objective of this investigation was the estimation of the precipitation and temperature return levels for three return periods (50, 100, and 150 years) classifying the data into groups with similar characteristics. Finally, the return level values were estimated with both GEV and GPD and with the three different estimation methods, revealing that the selected method can affect the return level values for both the parameter of precipitation and temperature.
Scott, Matthew; Kaler, Karan V. I. S.; Paul, Reginald
2001-06-15
Strong frequency-dependent fluid flow has been observed near the surface of microelectrode arrays. Modeling this phenomenon has proven to be difficult, with existing theories unable to account for the qualitative trend observed in the frequency spectra of this flow. Using recent electrode polarization results, a more comprehensive model of the double layer on the electrode surface is used to obtain good theoretical agreement with experimental data. Copyright 2001 Academic Press.
Simple technique of talc delivery for video-assisted talc pleurodesis.
Jutley, Rajwinder S; Waqar, Salman; Raha, Neil; Fenton, Paul; Sarkar, Pradip K
2009-02-01
It has been proven that talc is the sclerosant of choice for pleurodesis, especially for malignant effusions. Uniform talc deposition on the visceral pleura is often difficult, resulting in clump deposition with the use of an atomizer or bladder syringe delivery apparatus. We have devised a simple sterile apparatus that allows the operator to retain full control over the talc delivery rate and coat the lung uniformly under direct vision using a pressurized system.
The PSML format and library for norm-conserving pseudopotential data curation and interoperability
NASA Astrophysics Data System (ADS)
García, Alberto; Verstraete, Matthieu J.; Pouillon, Yann; Junquera, Javier
2018-06-01
Norm-conserving pseudopotentials are used by a significant number of electronic-structure packages, but the practical differences among codes in the handling of the associated data hinder their interoperability and make it difficult to compare their results. At the same time, existing formats lack provenance data, which makes it difficult to track and document computational workflows. To address these problems, we first propose a file format (PSML) that maps the basic concepts of the norm-conserving pseudopotential domain in a flexible form and supports the inclusion of provenance information and other important metadata. Second, we provide a software library (libPSML) that can be used by electronic structure codes to transparently extract the information in the file and adapt it to their own data structures, or to create converters for other formats. Support for the new file format has been already implemented in several pseudopotential generator programs (including ATOM and ONCVPSP), and the library has been linked with SIESTA and ABINIT, allowing them to work with the same pseudopotential operator (with the same local part and fully non-local projectors) thus easing the comparison of their results for the structural and electronic properties, as shown for several example systems. This methodology can be easily transferred to any other package that uses norm-conserving pseudopotentials, and offers a proof-of-concept for a general approach to interoperability.
Current evaluation and management of spondylolysis and spondylolisthesis.
McTimoney, C A Michelle; Micheli, Lyle J
2003-02-01
Spondylolysis occurs with a prevalence of 4% to 6% in the general population. Although the etiology of this lesion is still unclear, it has been shown to have both hereditary and acquired risk factors, with an increased prevalence in men and athletes participating in certain high-risk sports. Spondylolisthesis occurs in a significant proportion of individuals with bilateral spondylolysis. Predicting risk factors for progression of the slip in spondylolisthesis has proven difficult. Multiple imaging techniques are helpful in the diagnosis of spondylolysis and spondylolisthesis, with recent research addressing the utility of magnetic resonance imaging in the diagnosis and management of pars lesions. The management guidelines have remained largely unchanged since early recommendations. Recently, the addition of a bone growth stimulator to the management of difficult cases has shown promise.
Development and validation of a Kalman filter-based model for vehicle slip angle estimation
NASA Astrophysics Data System (ADS)
Gadola, M.; Chindamo, D.; Romano, M.; Padula, F.
2014-01-01
It is well known that vehicle slip angle is one of the most difficult parameters to measure on a vehicle during testing or racing activities. Moreover, the appropriate sensor is very expensive and it is often difficult to fit to a car, especially on race cars. We propose here a strategy to eliminate the need for this sensor by using a mathematical tool which gives a good estimation of the vehicle slip angle. A single-track car model, coupled with an extended Kalman filter, was used in order to achieve the result. Moreover, a tuning procedure is proposed that takes into consideration both nonlinear and saturation characteristics typical of vehicle lateral dynamics. The effectiveness of the proposed algorithm has been proven by both simulation results and real-world data.
On Improving Efficiency of Differential Evolution for Aerodynamic Shape Optimization Applications
NASA Technical Reports Server (NTRS)
Madavan, Nateri K.
2004-01-01
Differential Evolution (DE) is a simple and robust evolutionary strategy that has been provEn effective in determining the global optimum for several difficult optimization problems. Although DE offers several advantages over traditional optimization approaches, its use in applications such as aerodynamic shape optimization where the objective function evaluations are computationally expensive is limited by the large number of function evaluations often required. In this paper various approaches for improving the efficiency of DE are reviewed and discussed. Several approaches that have proven effective for other evolutionary algorithms are modified and implemented in a DE-based aerodynamic shape optimization method that uses a Navier-Stokes solver for the objective function evaluations. Parallelization techniques on distributed computers are used to reduce turnaround times. Results are presented for standard test optimization problems and for the inverse design of a turbine airfoil. The efficiency improvements achieved by the different approaches are evaluated and compared.
Management of stormwater facility maintenance residuals
DOT National Transportation Integrated Search
1998-06-01
Current research on stormwater maintenance residuals has revealed that the source and nature of these materials is extremely variable, that regulation can be ambiguous, and handling can be costly and difficult. From a regulatory perspective, data ind...
Countering Extremism; Beyond Interagency Cooperation
2011-04-18
such as health care, education and welfare for its constituents. Hizballah also garnered credit in Lebanon for forcing Israel to withdraw in... Minster , will likely make the official relationship with the GOL significantly more difficult. 24 “A
NASA Astrophysics Data System (ADS)
Dougan, Lorna
2015-11-01
Wherever we look on Earth - even in the most inhospitable places - we find life. But how do organisms manage to survive such difficult conditions? Lorna Dougan explains how physicists are helping to unravel the properties of “extremophile” life.
Case study of a floor-cleaning robot
NASA Astrophysics Data System (ADS)
Branch, Allan C.
1998-01-01
Developing the technologies suitable of ra high level robotic application such as cleaning a floor has proved extremely difficult. Developing the robot mobility technology has been a stumbling block and developing and integrating the applications technology to the machine and the mobility technology has also been a difficult stage in this quest, but doing so in a cost effective and realistic manner suitable for the market place and to compete with humans and manually operated machines has been the most difficult of all. This paper describes one of these quests spanning a 14 year period and resulting in what is hoped will be the world's first commercially manufactured household robot vacuum cleaner.
Molecular Imaging for Guiding Oncologic Prognosis and Therapy in Esophageal Adenocarcinoma
Yentz, Sarah; Wang, Thomas D.
2011-01-01
In the last 30 years, the incidence of esophageal adenocarcinoma has skyrocketed. Sadly, advances in treatment have not followed the same trend, and the prognosis for patients with esophageal adenocarcinoma remains poor with a 5-year survival rate of only 15%. Like most cancers, early detection is the key to improving prognosis, but this outcome has proven difficult in the esophagus for several reasons: 1) patients present with advanced disease because “alarm symptoms” such as dysphagia occur at a late stage, and 2) high-grade dysplasia (HGD) and early adenocarcinoma (ACA) are not visible on routine surveillance endoscopy. Currently, the recommended surveillance strategy involves collection of random biopsies, an imperfect technique that is limited by sampling error and is infrequently used because of the considerable time and cost it requires. Even in patients with biopsy-proven dysplasia, adequate guidance for clinical management decisions is still lacking. Dysplasia alone is not an entirely reliable biomarker for the risk of progression to adenocarcinoma because the natural history of this condition is extremely variable. Clearly, there is a need for additional biomarkers that can better characterize this disease, and thus improve our ability to treat patients on an individual basis. As we better understand the molecular changes that lead to the development of this cancer, new molecular biomarkers are needed to allow for more personalized diagnoses, surveillance and treatment. Targeted agents against EGFR, HER2/neu and VEGF are currently being evaluated for their role in combination chemotherapy for metastatic esophageal adenocarcinoma. As these studies progress, a reliable approach for determining receptor status in individual patients is essential. Molecular imaging uses fluorescent probes that target specific cell surface receptors, and has the potential to evaluate an individual patient’s gene expression profile. By topically applying fluorescent probes to dysplastic epithelium during endoscopy, a variety of receptors can be visualized, and the response to treatment can be monitored in real time. This technique can mitigate the limitations of current surveillance protocols, allow for improved cancer detection, and be used for truly personalized treatment in the future. PMID:21576902
MEMS Micro-Valve for Space Applications
NASA Technical Reports Server (NTRS)
Chakraborty, I.; Tang, W. C.; Bame, D. P.; Tang, T. K.
1998-01-01
We report on the development of a Micro-ElectroMechanical Systems (MEMS) valve that is designed to meet the rigorous performance requirements for a variety of space applications, such as micropropulsion, in-situ chemical analysis of other planets, or micro-fluidics experiments in micro-gravity. These systems often require very small yet reliable silicon valves with extremely low leak rates and long shelf lives. Also, they must survive the perils of space travel, which include unstoppable radiation, monumental shock and vibration forces, as well as extreme variations in temperature. Currently, no commercial MEMS valve meets these requirements. We at JPL are developing a piezoelectric MEMS valve that attempts to address the unique problem of space. We begin with proven configurations that may seem familiar. However, we have implemented some major design innovations that should produce a superior valve. The JPL micro-valve is expected to have an extremely low leak rate, limited susceptibility to particulates, vibration or radiation, as well as a wide operational temperature range.
Federal Register 2010, 2011, 2012, 2013, 2014
2013-08-20
... rule is extremely difficult due to the numerous variables associated with delivery (e.g., weather... 2 hours resulting from weather or unforeseen construction delays. NRMCA claims that these frequent...
DeGregoris, Gerard; Diwan, Sudhir
2010-01-01
Lower back and extremity pain in the amputee patient can be challenging to classify and treat. Radicular compression in a patient with lower limb amputation may present as or be superimposed upon phantom limb pain, creating diagnostic difficulties. Both patients and physicians classically find it difficult to discern phantom sensation from phantom limb pain and stump pain; radicular compression is often not considered. Many studies have shown back pain to be a significant cause of pain in lower limb amputees, but sciatica has been rarely reported in amputees. We present a case of L4/5 radiculitis in an above-knee amputee presenting as phantom radiculitis. Our patient is a 67 year old gentleman with new onset 10/10 pain in a phantom extremity superimposed upon a 40 year history of previously stable phantom limb pain. MRI showed a central disc herniation at L4/5 with compression of the traversing left L4 nerve root. Two fluoroscopically guided left transforaminal epidural steroid injections at the level of the L4 and L5 spinal nerve roots totally alleviated his new onset pain. At one year post injection, his phantom radiculitis pain was completely gone, though his underlying phantom limb pain remained. Lumbar radiculitis in lower extremity amputee patients may be difficult to differentiate from baseline phantom limb pain. When conservative techniques fail, fluoroscopically guided spinal nerve injection may be valuable in determining the etiology of lower extremity pain. Our experience supports the notion that epidural steroid injections can effectively treat phantom lumbar radiculitis in lower extremity amputees.
The past, present and future of cyber-physical systems: a focus on models.
Lee, Edward A
2015-02-26
This paper is about better engineering of cyber-physical systems (CPSs) through better models. Deterministic models have historically proven extremely useful and arguably form the kingpin of the industrial revolution and the digital and information technology revolutions. Key deterministic models that have proven successful include differential equations, synchronous digital logic and single-threaded imperative programs. Cyber-physical systems, however, combine these models in such a way that determinism is not preserved. Two projects show that deterministic CPS models with faithful physical realizations are possible and practical. The first project is PRET, which shows that the timing precision of synchronous digital logic can be practically made available at the software level of abstraction. The second project is Ptides (programming temporally-integrated distributed embedded systems), which shows that deterministic models for distributed cyber-physical systems have practical faithful realizations. These projects are existence proofs that deterministic CPS models are possible and practical.
NASA Technical Reports Server (NTRS)
Turnbull, D.
1984-01-01
The formation by melt quenching of such metastable structures as glassy or microcrystalline solids and highly supersaturated solutions is made possible by the extreme resistance of most melts to homophase crystal nucleation at deep undercooling. This nucleation resistance contrasts sharply with the very low kinetic resistance to the movement of crystal-melt interfaces, once formed, in metals and other fluid systems at even minute undercooling. The methods of nucleation study which have proven especially effective in bypassing nucleation by heterophase impurities thereby exposing the high resistance of melts to homophase nucleation may be summarized as follows: observation of the crystallization behavior of dispersed small droplets; drop tube experiments in which liquid drops solidify, under containerless conditions, during their fall in the tube; and observation of the crystallization of bulk specimens immersed in fluxes chosen to dissolve or otherwise deactivate (e.g., by wetting) heterophase nucleants. This method has proven to be remarkably effective in deactivating such nucleants in certain pure metals.
The Past, Present and Future of Cyber-Physical Systems: A Focus on Models
Lee, Edward A.
2015-01-01
This paper is about better engineering of cyber-physical systems (CPSs) through better models. Deterministic models have historically proven extremely useful and arguably form the kingpin of the industrial revolution and the digital and information technology revolutions. Key deterministic models that have proven successful include differential equations, synchronous digital logic and single-threaded imperative programs. Cyber-physical systems, however, combine these models in such a way that determinism is not preserved. Two projects show that deterministic CPS models with faithful physical realizations are possible and practical. The first project is PRET, which shows that the timing precision of synchronous digital logic can be practically made available at the software level of abstraction. The second project is Ptides (programming temporally-integrated distributed embedded systems), which shows that deterministic models for distributed cyber-physical systems have practical faithful realizations. These projects are existence proofs that deterministic CPS models are possible and practical. PMID:25730486
Río Tinto: A Geochemical and Mineralogical Terrestrial Analogue of Mars
Amils, Ricardo; Fernández-Remolar, David
2014-01-01
The geomicrobiological characterization of the water column and sediments of Río Tinto (Huelva, Southwestern Spain) have proven the importance of the iron and the sulfur cycles, not only in generating the extreme conditions of the habitat (low pH, high concentration of toxic heavy metals), but also in maintaining the high level of microbial diversity detected in the basin. It has been proven that the extreme acidic conditions of Río Tinto basin are not the product of 5000 years of mining activity in the area, but the consequence of an active underground bioreactor that obtains its energy from the massive sulfidic minerals existing in the Iberian Pyrite Belt. Two drilling projects, MARTE (Mars Astrobiology Research and Technology Experiment) (2003–2006) and IPBSL (Iberian Pyrite Belt Subsurface Life Detection) (2011–2015), were developed and carried out to provide evidence of subsurface microbial activity and the potential resources that support these activities. The reduced substrates and the oxidants that drive the system appear to come from the rock matrix. These resources need only groundwater to launch diverse microbial metabolisms. The similarities between the vast sulfate and iron oxide deposits on Mars and the main sulfide bioleaching products found in the Tinto basin have given Río Tinto the status of a geochemical and mineralogical Mars terrestrial analogue. PMID:25370383
Laboratory Cultivation and Maintenance of Borrelia miyamotoi.
Stone, Brandee L; Brissette, Catherine A
2016-08-12
Borrelia miyamotoi is a relapsing fever tick-borne pathogen found in Ixodes spp. (hard) ticks. In vitro culturing has proven difficult despite initial reports of cultures maintained in Barbour-Stoenner-Kelly-II (BSK-II) medium. The ability to culture in vitro opens many avenues for investigating the genetics and physiology of bacterial species. This unit describes methods for the maintenance and cultivation of B. miyamotoi in liquid medium. © 2016 by John Wiley & Sons, Inc. Copyright © 2016 John Wiley & Sons, Inc.
Extremes in ecology: Avoiding the misleading effects of sampling variation in summary analyses
Link, W.A.; Sauer, J.R.
1996-01-01
Surveys such as the North American Breeding Bird Survey (BBS) produce large collections of parameter estimates. One's natural inclination when confronted with lists of parameter estimates is to look for the extreme values: in the BBS, these correspond to the species that appear to have the greatest changes in population size through time. Unfortunately, extreme estimates are liable to correspond to the most poorly estimated parameters. Consequently, the most extreme parameters may not match up with the most extreme parameter estimates. The ranking of parameter values on the basis of their estimates are a difficult statistical problem. We use data from the BBS and simulations to illustrate the potential misleading effects of sampling variation in rankings of parameters. We describe empirical Bayes and constrained empirical Bayes procedures which provide partial solutions to the problem of ranking in the presence of sampling variation.
Snow Depth Mapping at a Basin-Wide Scale in the Western Arctic Using UAS Technology
NASA Astrophysics Data System (ADS)
de Jong, T.; Marsh, P.; Mann, P.; Walker, B.
2015-12-01
Assessing snow depths across the Arctic has proven to be extremely difficult due to the variability of snow depths at scales from metres to 100's of metres. New Unmanned Aerial Systems (UAS) technology provides the possibility to obtain centimeter level resolution imagery (~3cm), and to create Digital Surface Models (DSM) based on the Structure from Motion method. However, there is an ongoing need to quantify the accuracy of this method over different terrain and vegetation types across the Arctic. In this study, we used a small UAS equipped with a high resolution RGB camera to create DSMs over a 1 km2 watershed in the western Canadian Arctic during snow (end of winter) and snow-free periods. To improve the image georeferencing, 15 Ground Control Points were marked across the watershed and incorporated into the DSM processing. The summer DSM was subtracted from the snowcovered DSM to deliver snow depth measurements across the entire watershed. These snow depth measurements were validated by over 2000 snow depth measurements. This technique has the potential to improve larger scale snow depth mapping across watersheds by providing snow depth measurements at a ~3 cm . The ability of mapping both shallow snow (less than 75cm) covering much of the basin and snow patches (up to 5 m in depth) that cover less than 10% of the basin, but contain a significant portion of total basin snowcover, is important for both water resource applications, as well as for testing snow models.
Stress fractures of the foot and ankle in athletes.
Mayer, Stephanie W; Joyner, Patrick W; Almekinders, Louis C; Parekh, Selene G
2014-11-01
Stress fractures of the foot and ankle are a common problem encountered by athletes of all levels and ages. These injuries can be difficult to diagnose and may be initially evaluated by all levels of medical personnel. Clinical suspicion should be raised with certain history and physical examination findings. Scientific and review articles were searched through PubMed (1930-2012) with search terms including stress fractures and 1 of the following: foot ankle, medial malleolus, lateral malleolus, calcaneus, talus, metatarsal, cuboid, cuneiform, sesamoid, or athlete. Clinical review. Level 5. Stress fractures of the foot and ankle can be divided into low and high risk based upon their propensity to heal without complication. A wide variety of nonoperative strategies are employed based on the duration of symptoms, type of fracture, and patient factors, such as activity type, desire to return to sport, and compliance. Operative management has proven superior in several high-risk types of stress fractures. Evidence on pharmacotherapy and physiologic therapy such as bone stimulators is evolving. A high index of suspicion for stress fractures is appropriate in many high-risk groups of athletes with lower extremity pain. Proper and timely work-up and treatment is successful in returning these athletes to sport in many cases. Low-risk stress fracture generally requires only activity modification while high-risk stress fracture necessitates more aggressive intervention. The specific treatment of these injuries varies with the location of the stress fracture and the goals of the patient.
Allosteric Modulators for the Treatment of Schizophrenia: Targeting Glutamatergic Networks
Menniti, Frank S.; Lindsley, Craig W.; Conn, P. Jeffrey; Pandit, Jayvardhan; Zagouras, Panayiotis; Volkmann, Robert A.
2013-01-01
Schizophrenia is a highly debilitating mental disorder which afflicts approximately 1% of the global population. Cognitive and negative deficits account for the lifelong disability associated with schizophrenia, whose symptoms are not effectively addressed by current treatments. New medicines are needed to treat these aspects of the disease. Neurodevelopmental, neuropathological, genetic, and behavioral pharmacological data indicate that schizophrenia stems from a dysfunction of glutamate synaptic transmission, particularly in frontal cortical networks. A number of novel pre- and postsynaptic mechanisms affecting glutamatergic synaptic transmission have emerged as viable targets for schizophrenia. While developing orthosteric glutamatergic agents for these targets has proven extremely difficult, targeting allosteric sites of these targets has emerged as a promising alternative. From a medicinal chemistry perspective, allosteric sites provide an opportunity of finding agents with better drug-like properties and greater target specificity. Furthermore, allosteric modulators are better suited to maintaining the highly precise temporal and spatial aspects of glutamatergic synaptic transmission. Herein, we review neuropathological and genomic/genetic evidence underscoring the importance of glutamate synaptic dysfunction in the etiology of schizophrenia and make a case for allosteric targets for therapeutic intervention. We review progress in identifying allosteric modulators of AMPA receptors, NMDA receptors, and metabotropic glutamate receptors, all with the aim of restoring physiological glutamatergic synaptic transmission. Challenges remain given the complexity of schizophrenia and the difficulty in studying cognition in animals and humans. Nonetheless, important compounds have emerged from these efforts and promising preclinical and variable clinical validation has been achieved. PMID:23409764
A first constraint on the average mass of ultra-diffuse galaxies from weak gravitational lensing
NASA Astrophysics Data System (ADS)
Sifón, Cristóbal; van der Burg, Remco F. J.; Hoekstra, Henk; Muzzin, Adam; Herbonnet, Ricardo
2018-01-01
The recent discovery of thousands of ultra-diffuse galaxies (UDGs) in nearby galaxy clusters has opened a new window into the process of galaxy formation and evolution. Several scenarios have been proposed to explain the formation history of UDGs, and their ability to survive in the harsh cluster environments. A key requirement to distinguish between these scenarios is a measurement of their halo masses which, due to their low surface brightnesses, has proven difficult if one relies on stellar tracers of the potential. We exploit weak gravitational lensing, a technique that does not depend on these baryonic tracers, to measure the average subhalo mass of 784 UDGs selected in 18 clusters at z ≤ 0.09. Our sample of UDGs has a median stellar mass 〈m⋆〉 = 2 × 108 M⊙ and a median effective radius 〈reff〉 = 2.8 kpc. We constrain the average mass of subhaloes within 30 kpc to log mUDG(r < 30 kpc)/M⊙ ≤ 10.99 at 95 per cent credibility, implying an effective virial mass log m200/M⊙ ≤ 11.80, and a lower limit on the stellar mass fraction within 10 kpc of 1.0 per cent. Such mass is consistent with a simple extrapolation of the subhalo-to-stellar mass relation of typical satellite galaxies in massive clusters. However, our analysis is not sensitive to scatter about this mean mass; the possibility remains that extreme UDGs reside in haloes as massive as the Milky Way.
Tigers and their prey: Predicting carnivore densities from prey abundance
Karanth, K.U.; Nichols, J.D.; Kumar, N.S.; Link, W.A.; Hines, J.E.
2004-01-01
The goal of ecology is to understand interactions that determine the distribution and abundance of organisms. In principle, ecologists should be able to identify a small number of limiting resources for a species of interest, estimate densities of these resources at different locations across the landscape, and then use these estimates to predict the density of the focal species at these locations. In practice, however, development of functional relationships between abundances of species and their resources has proven extremely difficult, and examples of such predictive ability are very rare. Ecological studies of prey requirements of tigers Panthera tigris led us to develop a simple mechanistic model for predicting tiger density as a function of prey density. We tested our model using data from a landscape-scale long-term (1995-2003) field study that estimated tiger and prey densities in 11 ecologically diverse sites across India. We used field techniques and analytical methods that specifically addressed sampling and detectability, two issues that frequently present problems in macroecological studies of animal populations. Estimated densities of ungulate prey ranged between 5.3 and 63.8 animals per km2. Estimated tiger densities (3.2-16.8 tigers per 100 km2) were reasonably consistent with model predictions. The results provide evidence of a functional relationship between abundances of large carnivores and their prey under a wide range of ecological conditions. In addition to generating important insights into carnivore ecology and conservation, the study provides a potentially useful model for the rigorous conduct of macroecological science.
Extremal Optimization for estimation of the error threshold in topological subsystem codes at T = 0
NASA Astrophysics Data System (ADS)
Millán-Otoya, Jorge E.; Boettcher, Stefan
2014-03-01
Quantum decoherence is a problem that arises in implementations of quantum computing proposals. Topological subsystem codes (TSC) have been suggested as a way to overcome decoherence. These offer a higher optimal error tolerance when compared to typical error-correcting algorithms. A TSC has been translated into a planar Ising spin-glass with constrained bimodal three-spin couplings. This spin-glass has been considered at finite temperature to determine the phase boundary between the unstable phase and the stable phase, where error recovery is possible.[1] We approach the study of the error threshold problem by exploring ground states of this spin-glass with the Extremal Optimization algorithm (EO).[2] EO has proven to be a effective heuristic to explore ground state configurations of glassy spin-systems.[3
Arctic sea ice, Eurasia snow, and extreme winter haze in China.
Zou, Yufei; Wang, Yuhang; Zhang, Yuzhong; Koo, Ja-Ho
2017-03-01
The East China Plains (ECP) region experienced the worst haze pollution on record for January in 2013. We show that the unprecedented haze event is due to the extremely poor ventilation conditions, which had not been seen in the preceding three decades. Statistical analysis suggests that the extremely poor ventilation conditions are linked to Arctic sea ice loss in the preceding autumn and extensive boreal snowfall in the earlier winter. We identify the regional circulation mode that leads to extremely poor ventilation over the ECP region. Climate model simulations indicate that boreal cryospheric forcing enhances the regional circulation mode of poor ventilation in the ECP region and provides conducive conditions for extreme haze such as that of 2013. Consequently, extreme haze events in winter will likely occur at a higher frequency in China as a result of the changing boreal cryosphere, posing difficult challenges for winter haze mitigation but providing a strong incentive for greenhouse gas emission reduction.
Arctic sea ice, Eurasia snow, and extreme winter haze in China
Zou, Yufei; Wang, Yuhang; Zhang, Yuzhong; Koo, Ja-Ho
2017-01-01
The East China Plains (ECP) region experienced the worst haze pollution on record for January in 2013. We show that the unprecedented haze event is due to the extremely poor ventilation conditions, which had not been seen in the preceding three decades. Statistical analysis suggests that the extremely poor ventilation conditions are linked to Arctic sea ice loss in the preceding autumn and extensive boreal snowfall in the earlier winter. We identify the regional circulation mode that leads to extremely poor ventilation over the ECP region. Climate model simulations indicate that boreal cryospheric forcing enhances the regional circulation mode of poor ventilation in the ECP region and provides conducive conditions for extreme haze such as that of 2013. Consequently, extreme haze events in winter will likely occur at a higher frequency in China as a result of the changing boreal cryosphere, posing difficult challenges for winter haze mitigation but providing a strong incentive for greenhouse gas emission reduction. PMID:28345056
Durable nonslip stainless-steel drivebelts
NASA Technical Reports Server (NTRS)
Bahiman, H.
1979-01-01
Two toothed stainless-steel drive belt retains its strength and flexibility in extreme heat or cold, intense radiation, or under high loading. Belt does not stretch or slip and is particularly suited to machinery for which replacement is difficult or impossible.
Elephantiasis nostras verrucosa on the buttocks and sacrum of two immobile men.
Setyadi, Hedy G; Iacco, Megan Reif; Shwayder, Tor A; Ormsby, Adrian
2011-02-15
Though typically involving the lower extremities, elephantiasis nostras verrucosa (ENV) can occur in any area affected by lymphedema. Here we report two cases of ENV: one is a biopsy-proven case and the other is a clinically diagnosed case. Both occurred on the buttocks and sacrum of immobile, morbidly obese men who were persistently in the supine or seated position. Whereas classic ENV is not uncommon, this striking presentation on these unusual areas is quite rare.
The use of hydro-dynamic models in the practice-oriented education of engineering students
NASA Astrophysics Data System (ADS)
Sziebert, J.; Zellei, L.; Tamás, E. A.
2009-04-01
Management tasks related to open channel flows became rather comprehensive and multi-disciplinary, particularly with the predominancy of nature management aspects. The water regime of our rivers has proven to reach extremities more and more frequently in the past decades. In order to develop and analyse alternative solutions and to handle and resolve conflicts of interests, we apply 1D hydro-dynamic models in education for the explanation of processes and to improve practical skills of our students.
Equipment modifications for perennial nutsedge control in fallow organic transition
USDA-ARS?s Scientific Manuscript database
Perennial nutsedges are extremely difficult to control in organic crop transition and production systems. Herbicides suitable for use in certified organic production do not adequately control perennial nutsedges. Cultural and mechanical control are partially effective in controlling perennial nuts...
Acupuncture and Deaf-Mutism--An Essay in Cross-Cultural Defectology
ERIC Educational Resources Information Center
Sutton, Andrew
1977-01-01
Describes reportedly successful treatment of deaf-mutes in China by acupuncture, and suggests that the disorders might have been more psychological than physical. The author comments that interpretation of poorly documented reports from unfamiliar cultures is extremely difficult. (AV)
Malignant solitary fibrous tumor in the extremity: Cytopathologic findings
Khanchel, Fatma; Driss, Maha; Mrad, Karima; Romdhane, Khaled Ben
2012-01-01
Malignant solitary fibrous tumor (SFT) is an extremely rare neoplasm. There are only rare published accounts of the cytopathologic features of this tumor. We report a case of a 59-year-old woman presented with a 10-year history of a right thigh mass. A preoperative fine needle aspiration (FNA) was performed. Smears were hypercellular, with cohesive and crowded tissue fragments, haphazard cell arrangements and many single cells. The tumor cells were polymorphous, plump spindled or round with often indented or bare nuclei. A differential diagnosis of low grade sarcoma was favored. The diagnosis of malignant SFT is extremely difficult on FNA and must be included in the differential diagnosis of spindle cell neoplasms. PMID:22787298
Evolution caused by extreme events.
Grant, Peter R; Grant, B Rosemary; Huey, Raymond B; Johnson, Marc T J; Knoll, Andrew H; Schmitt, Johanna
2017-06-19
Extreme events can be a major driver of evolutionary change over geological and contemporary timescales. Outstanding examples are evolutionary diversification following mass extinctions caused by extreme volcanism or asteroid impact. The evolution of organisms in contemporary time is typically viewed as a gradual and incremental process that results from genetic change, environmental perturbation or both. However, contemporary environments occasionally experience strong perturbations such as heat waves, floods, hurricanes, droughts and pest outbreaks. These extreme events set up strong selection pressures on organisms, and are small-scale analogues of the dramatic changes documented in the fossil record. Because extreme events are rare, almost by definition, they are difficult to study. So far most attention has been given to their ecological rather than to their evolutionary consequences. We review several case studies of contemporary evolution in response to two types of extreme environmental perturbations, episodic (pulse) or prolonged (press). Evolution is most likely to occur when extreme events alter community composition. We encourage investigators to be prepared for evolutionary change in response to rare events during long-term field studies.This article is part of the themed issue 'Behavioural, ecological and evolutionary responses to extreme climatic events'. © 2017 The Author(s).
Congenital Differences of the Upper Extremity: Classification and Treatment Principles
2011-01-01
For hand surgeons, the treatment of children with congenital differences of the upper extremity is challenging because of the diverse spectrum of conditions encountered, but the task is also rewarding because it provides surgeons with the opportunity to impact a child's growth and development. An ideal classification of congenital differences of the upper extremity would reflect the full spectrum of morphologic abnormalities and encompass etiology, a guide to treatment, and provide prognoses. In this report, I review current classification systems and discuss their contradictions and limitations. In addition, I present a modified classification system and provide treatment principles. As our understanding of the etiology of congenital differences of the upper extremity increases and as experience of treating difficult cases accumulates, even an ideal classification system and optimal treatment strategies will undoubtedly continue to evolve. PMID:21909463
Lin, Chung-Wei; Tsai, Tzu-Jung; Cheng, Tsung-Yen; Wei, Hung-Kuang; Hung, Chen-Fang; Chen, Yin-Yin; Chen, Chii-Ming
2016-07-01
Laparoscopic liver resection (LLR) has been proven to be feasible and safe. However, it is a difficult and complex procedure with a steep learning curve. The aim of this study was to evaluate the learning curve of LLR at our institutions since 2008. One hundred and twenty-six consecutive LLRs were included from May 2008 to December 2014. Patient characteristics, operative data, and surgical outcomes were collected prospectively and analyzed. The median tumor size was 25 mm (range 5-90 mm), and 96 % of the resected tumors were malignant. 41.3 % (52/126) of patients had pathologically proven liver cirrhosis. The median operation time was 216 min (range 40-602 min) with a median blood loss of 100 ml (range 20-2300 ml). The median length of hospital stay was 4 days (range 2-10 days). Six major postoperative complications occurred in this series, and there was no 90-day postoperative mortality. Regarding the incidence of major operative events including operation time longer than 300 min, perioperative blood loss above 500 ml, and major postoperative complications, the learning curve [as evaluated by the cumulative sum (CUSUM) technique] showed its first reverse after 22 cases. The indication of laparoscopic resection in this series extended after 60 cases to include tumors located in difficult locations (segments 4a, 7, 8) and major hepatectomy. CUSUM showed that the incidence of major operative events proceeded to increase again, and the second reverse was noted after an additional 40 cases of experience. Location of the tumor in a difficult area emerged as a significant predictor of major operative events. In carefully selected patients, CUSUM analysis showed 22 cases were needed to overcome the learning curve for minor LLR.
Ramiro-H, Manuel; Cruz-A, J Enrique; García-Gómez, Francisco
2017-01-01
The evaluation and quantification of scientific activity is an extremely complex task. Evaluation of research results is often difficult, and different indicators for the quantification and evaluation of scientific publications have been identified, as well as the development and success of the training programs of researchers.
n-Alcohol/Water Partition Coefficients for Decachlorobiphenyl (PCB 209)
Measurements of n-octanol/water partition coefficients (Kow) for highly hydrophobic chemicals are extremely difficult and are rarely made, in part due to the large volumes of water typically needed to quantify these compounds in the aqueous phase. An extrapolation approach using ...
A proven knowledge-based approach to prioritizing process information
NASA Technical Reports Server (NTRS)
Corsberg, Daniel R.
1991-01-01
Many space-related processes are highly complex systems subject to sudden, major transients. In any complex process control system, a critical aspect is rapid analysis of the changing process information. During a disturbance, this task can overwhelm humans as well as computers. Humans deal with this by applying heuristics in determining significant information. A simple, knowledge-based approach to prioritizing information is described. The approach models those heuristics that humans would use in similar circumstances. The approach described has received two patents and was implemented in the Alarm Filtering System (AFS) at the Idaho National Engineering Laboratory (INEL). AFS was first developed for application in a nuclear reactor control room. It has since been used in chemical processing applications, where it has had a significant impact on control room environments. The approach uses knowledge-based heuristics to analyze data from process instrumentation and respond to that data according to knowledge encapsulated in objects and rules. While AFS cannot perform the complete diagnosis and control task, it has proven to be extremely effective at filtering and prioritizing information. AFS was used for over two years as a first level of analysis for human diagnosticians. Given the approach's proven track record in a wide variety of practical applications, it should be useful in both ground- and space-based systems.
NASA Technical Reports Server (NTRS)
Von Roos, O.
1978-01-01
The limitations of the detectability of extremely weak signals (gravitational radiation for instance) imposed by Heisenberg's uncertainty principle on the sequential determination of those signals have been explored recently. A variety of schemes have been proposed to circumvent these limitations. Although all of the earlier attempts have been proven fruitless a recent proposal seems to be quite promising. The scheme, consisting of two harmonic oscillators interacting with each other in a peculiar way, allows for an exact analytical solution which is derived here. If it can be assumed that the expectation value of one of the canonical variables of the total system suffices to monitor the weak signal it can be shown that, in the absence of thermal noise, arbitrarily weak signals can in principle be measured without interference from the uncertainty principle.
Bowman, Mary H; Taub, Edward; Uswatte, Gitendra; Delgado, Adriana; Bryson, Camille; Morris, David M; McKay, Staci; Mark, Victor W
2006-01-01
Constraint-Induced Movement therapy (CI therapy) is a recognized rehabilitation approach for persons having stroke with mild to moderately severe motor upper extremity deficits. To date, no rehabilitation treatment protocol has been proven effective that addresses both motor performance and spontaneous upper extremity use in the life situation for chronic stroke participants having severe upper extremity impairment with no active finger extension or thumb abduction. This case report describes treatment of a chronic stroke participant with a plegic hand using a CI therapy protocol that combines CI therapy with selected occupational and physical therapy techniques. Treatment consisted of six sessions of adaptive equipment and upper extremity orthotics training followed by a three-week, six-hour daily intervention of CI therapy plus neurodevelopmental treatment. Outcome measures included the Motor Activity Log for very low functioning patients (Grade 5 MAL), upper extremity portion of the Fugl-Meyer Motor Assessment, Graded Wolf Motor Function Test - for very low functioning patients (gWMFT- Grade 5), and Modified Ashworth Scale. The participant showed improvement on each outcome measure with the largest improvement on the Grade 5 MAL. In follow-up, the participant had good retention of his gains in motor performance and use of his more affected arm for real world activities after 3 months; after a one-week brush-up at 3 months, and at one year post-treatment.
Rider, Lisa G.; Dankó, Katalin; Miller, Frederick W.
2016-01-01
Purpose of review Clinical registries and biorepositories have proven extremely useful in many studies of diseases, especially rare diseases. Given their rarity and diversity, the idiopathic inflammatory myopathies, or myositis syndromes, have benefited from individual researchers’ collections of cohorts of patients. Major efforts are being made to establish large registries and biorepositories that will allow many additional studies to be performed that were not possible before. Here we describe the registries developed by investigators and patient support groups that are currently available for collaborative research purposes. Recent findings We have identified 46 myositis research registries, including many with biorepositories, which have been developed for a wide variety of purposes and have resulted in great advances in understanding the range of phenotypes, clinical presentations, risk factors, pathogenic mechanisms, outcome assessment, therapeutic responses, and prognoses. These are now available for collaborative use to undertake additional studies. Two myositis patient registries have been developed for research, and myositis patient support groups maintain demographic registries with large numbers of patients available to be contacted for potential research participation. Summary Investigator-initiated myositis research registries and biorepositories have proven extremely useful in understanding many aspects of these rare and diverse autoimmune diseases. These registries and biorepositories, in addition to those developed by myositis patient support groups, deserve continued support to maintain the momentum in this field as they offer major opportunities to improve understanding of the pathogenesis and treatment of these diseases in cost-effective ways. PMID:25225838
Rider, Lisa G; Dankó, Katalin; Miller, Frederick W
2014-11-01
Clinical registries and biorepositories have proven extremely useful in many studies of diseases, especially rare diseases. Given their rarity and diversity, the idiopathic inflammatory myopathies, or myositis syndromes, have benefited from individual researchers' collections of cohorts of patients. Major efforts are being made to establish large registries and biorepositories that will allow many additional studies to be performed that were not possible before. Here, we describe the registries developed by investigators and patient support groups that are currently available for collaborative research purposes. We have identified 46 myositis research registries, including many with biorepositories, which have been developed for a wide variety of purposes and have resulted in great advances in understanding the range of phenotypes, clinical presentations, risk factors, pathogenic mechanisms, outcome assessment, therapeutic responses, and prognoses. These are now available for collaborative use to undertake additional studies. Two myositis patient registries have been developed for research, and myositis patient support groups maintain demographic registries with large numbers of patients available to be contacted for potential research participation. Investigator-initiated myositis research registries and biorepositories have proven extremely useful in understanding many aspects of these rare and diverse autoimmune diseases. These registries and biorepositories, in addition to those developed by myositis patient support groups, deserve continued support to maintain the momentum in this field as they offer major opportunities to improve understanding of the pathogenesis and treatment of these diseases in cost-effective ways.
Method For Synthesizing Extremely High-Temperature Melting Materials
Saboungi, Marie-Louise; Glorieux, Benoit
2005-11-22
The invention relates to a method of synthesizing high-temperature melting materials. More specifically the invention relates to a containerless method of synthesizing very high temperature melting materials such as borides, carbides and transition-metal, lanthanide and actinide oxides, using an Aerodynamic Levitator and a laser. The object of the invention is to provide a method for synthesizing extremely high-temperature melting materials that are otherwise difficult to produce, without the use of containers, allowing the manipulation of the phase (amorphous/crystalline/metastable) and permitting changes of the environment such as different gaseous compositions.
Method for synthesizing extremely high-temperature melting materials
Saboungi, Marie-Louise; Glorieux, Benoit
2007-11-06
The invention relates to a method of synthesizing high-temperature melting materials. More specifically the invention relates to a containerless method of synthesizing very high temperature melting materials such as carbides and transition-metal, lanthanide and actinide oxides, using an aerodynamic levitator and a laser. The object of the invention is to provide a method for synthesizing extremely high-temperature melting materials that are otherwise difficult to produce, without the use of containers, allowing the manipulation of the phase (amorphous/crystalline/metastable) and permitting changes of the environment such as different gaseous compositions.
Surface properties of Indonesian-made narrow dynamic compression plates.
Dewo, P; Sharma, P K; van der Tas, H F; van der Houwen, E B; Timmer, M; Magetsari, R; Busscher, H J; van Horn, J R; Verkerke, G J
2008-07-01
The enormous need of orthopaedic (surgical) implants such as osteosynthesis plates is difficult to be fulfilled in developing countries commonly rely on imported ones. One of the alternatives is utilization of local resources, but only after they have been proven safe to use, to overcome this problem. Surface properties are some of the determining factors of safety for those implants. We have succeeded in developing prototype of osteosynthesis plate and the results indicate that Indonesian-made plates need improvement with regards to the surface quality of physical characterization.
DOE Office of Scientific and Technical Information (OSTI.GOV)
Ran, Hao; de Riese, Tamara; Llorens, Maria-Gema
The forty-year history of the Journal of Structural Geology has recorded an enormous increase in the description, interpretation and modelling of deformation structures. Amongst factors that control deformation and the resulting structures, mechanical anisotropy has proven difficult to tackle. Using a Fast Fourier Transform-based numerical solver for viscoplastic deformation of crystalline materials, we illustrate in this paper how mechanical anisotropy has a profound effect on developing structures, such as crenulation cleavages, porphyroclast geometry and the initiation of shear bands and shear zones.
Effect of a road safety training program on drivers' comparative optimism.
Perrissol, Stéphane; Smeding, Annique; Laumond, Francis; Le Floch, Valérie
2011-01-01
Reducing comparative optimism regarding risk perceptions in traffic accidents has been proven to be particularly difficult (Delhomme, 2000). This is unfortunate because comparative optimism is assumed to impede preventive action. The present study tested whether a road safety training course could reduce drivers' comparative optimism in high control situations. Results show that the training course efficiently reduced comparative optimism in high control, but not in low control situations. Mechanisms underlying this finding and implications for the design of road safety training courses are discussed. Copyright © 2010 Elsevier Ltd. All rights reserved.
Structure in gamma ray burst time profiles: Statistical Analysis 1
NASA Technical Reports Server (NTRS)
Lestrade, John Patrick
1992-01-01
Since its launch on April 5, 1991, the Burst And Transient Source Experiment (BATSE) has observed and recorded over 500 gamma-ray bursts (GRB). The analysis of the time profiles of these bursts has proven to be difficult. Attempts to find periodicities through Fourier analysis have been fruitless except one celebrated case. Our goal is to be able to qualify the observed time-profiles structure. Before applying this formation to bursts, we have tested it on profiles composed of random Poissonian noise. This paper is a report of those preliminary results.
Ran, Hao; de Riese, Tamara; Llorens, Maria-Gema; ...
2018-05-20
The forty-year history of the Journal of Structural Geology has recorded an enormous increase in the description, interpretation and modelling of deformation structures. Amongst factors that control deformation and the resulting structures, mechanical anisotropy has proven difficult to tackle. Using a Fast Fourier Transform-based numerical solver for viscoplastic deformation of crystalline materials, we illustrate in this paper how mechanical anisotropy has a profound effect on developing structures, such as crenulation cleavages, porphyroclast geometry and the initiation of shear bands and shear zones.
Acute Alcoholic Hepatitis: Therapy.
Phillips, Paulina K; Lucey, Michael R
2016-08-01
Alcoholic hepatitis (AH) causes great morbidity and mortality in the United States and throughout the world. Advances in therapy have proven difficult. In part, this reflects challenges in diagnosis, including the distinction between AH and acute-on-chronic liver failure. Liver biopsy is the best method to clarify the cause in circumstances whereby conflicting clinical data confound the diagnosis. All treatment of AH begins with abstinence from alcohol. All patients with AH should be given sufficient nutrition. Prednisolone has become the principal agent for treating patients with severe AH. Copyright © 2016 Elsevier Inc. All rights reserved.
Applied extreme-value statistics
DOE Office of Scientific and Technical Information (OSTI.GOV)
Kinnison, R.R.
1983-05-01
The statistical theory of extreme values is a well established part of theoretical statistics. Unfortunately, it is seldom part of applied statistics and is infrequently a part of statistical curricula except in advanced studies programs. This has resulted in the impression that it is difficult to understand and not of practical value. In recent environmental and pollution literature, several short articles have appeared with the purpose of documenting all that is necessary for the practical application of extreme value theory to field problems (for example, Roberts, 1979). These articles are so concise that only a statistician can recognise all themore » subtleties and assumptions necessary for the correct use of the material presented. The intent of this text is to expand upon several recent articles, and to provide the necessary statistical background so that the non-statistician scientist can recognize and extreme value problem when it occurs in his work, be confident in handling simple extreme value problems himself, and know when the problem is statistically beyond his capabilities and requires consultation.« less
Exact simulation of max-stable processes.
Dombry, Clément; Engelke, Sebastian; Oesting, Marco
2016-06-01
Max-stable processes play an important role as models for spatial extreme events. Their complex structure as the pointwise maximum over an infinite number of random functions makes their simulation difficult. Algorithms based on finite approximations are often inexact and computationally inefficient. We present a new algorithm for exact simulation of a max-stable process at a finite number of locations. It relies on the idea of simulating only the extremal functions, that is, those functions in the construction of a max-stable process that effectively contribute to the pointwise maximum. We further generalize the algorithm by Dieker & Mikosch (2015) for Brown-Resnick processes and use it for exact simulation via the spectral measure. We study the complexity of both algorithms, prove that our new approach via extremal functions is always more efficient, and provide closed-form expressions for their implementation that cover most popular models for max-stable processes and multivariate extreme value distributions. For simulation on dense grids, an adaptive design of the extremal function algorithm is proposed.
Laparoscopic access with a visualizing trocar.
Wolf, J S
1997-01-01
Although useful in most situations, there are several inherent disadvantages of the standard laparoscopic access techniques of Veress needle insertion and Hasson-type cannula placement. Veress needle placement may be hazardous in patients at high risk for intraabdominal adhesions and difficult in patients who are obese. The usual alternative, the Hasson-type cannula, often does not provide a good gas seal. As another option, the use of a visualizing trocar (OPTIVIEW) has proven to be effective in the initial experience at the University of Michigan. The inner trocar of the visualizing trocar is hollow except for a clear plastic conical tip with two external ridges. The trocar-cannula assembly is passed through tissue layers to enter the operative space under direct vision from a 10-mm zero-degree laparoscope placed into the trocar. Results suggest that this technique is an excellent alternative to Veress needle placement when laparoscopic access is likely to be hazardous or difficult.
Ahmad, Nasir; Higgins, Irina; Walker, Kerry M. M.; Stringer, Simon M.
2016-01-01
Attempting to explain the perceptual qualities of pitch has proven to be, and remains, a difficult problem. The wide range of sounds which elicit pitch and a lack of agreement across neurophysiological studies on how pitch is encoded by the brain have made this attempt more difficult. In describing the potential neural mechanisms by which pitch may be processed, a number of neural networks have been proposed and implemented. However, no unsupervised neural networks with biologically accurate cochlear inputs have yet been demonstrated. This paper proposes a simple system in which pitch representing neurons are produced in a biologically plausible setting. Purely unsupervised regimes of neural network learning are implemented and these prove to be sufficient in identifying the pitch of sounds with a variety of spectral profiles, including sounds with missing fundamental frequencies and iterated rippled noises. PMID:27047368
Diode laser (980nm) cartilage reshaping
NASA Astrophysics Data System (ADS)
El Kharbotly, A.; El Tayeb, T.; Mostafa, Y.; Hesham, I.
2011-03-01
Loss of facial or ear cartilage due to trauma or surgery is a major challenge to the otolaryngologists and plastic surgeons as the complicated geometric contours are difficult to be animated. Diode laser (980 nm) has been proven effective in reshaping and maintaining the new geometric shape achieved by laser. This study focused on determining the optimum laser parameters needed for cartilage reshaping with a controlled water cooling system. Harvested animal cartilages were angulated with different degrees and irradiated with different diode laser powers (980nm, 4x8mm spot size). The cartilage specimens were maintained in a deformation angle for two hours after irradiation then released for another two hours. They were serially measured and photographed. High-power Diode laser irradiation with water cooling is a cheep and effective method for reshaping the cartilage needed for reconstruction of difficult situations in otorhinolaryngologic surgery. Key words: cartilage,diode laser (980nm), reshaping.
An efficient field and laboratory workflow for plant phylotranscriptomic projects1
Yang, Ya; Moore, Michael J.; Brockington, Samuel F.; Timoneda, Alfonso; Feng, Tao; Marx, Hannah E.; Walker, Joseph F.; Smith, Stephen A.
2017-01-01
Premise of the study: We describe a field and laboratory workflow developed for plant phylotranscriptomic projects that involves cryogenic tissue collection in the field, RNA extraction and quality control, and library preparation. We also make recommendations for sample curation. Methods and Results: A total of 216 frozen tissue samples of Caryophyllales and other angiosperm taxa were collected from the field or botanical gardens. RNA was extracted, stranded mRNA libraries were prepared, and libraries were sequenced on Illumina HiSeq platforms. These included difficult mucilaginous tissues such as those of Cactaceae and Droseraceae. Conclusions: Our workflow is not only cost effective (ca. $270 per sample, as of August 2016, from tissue to reads) and time efficient (less than 50 h for 10–12 samples including all laboratory work and sample curation), but also has proven robust for extraction of difficult samples such as tissues containing high levels of secondary compounds. PMID:28337391
Towards a Functionally-Formed Air Traffic System-of-Systems
NASA Technical Reports Server (NTRS)
Conway, Sheila R.; Consiglio, Maria C.
2005-01-01
Incremental improvements to the national aviation infrastructure have not resulted in sufficient increases in capacity and flexibility to meet emerging demand. Unfortunately, revolutionary changes capable of substantial and rapid increases in capacity have proven elusive. Moreover, significant changes have been difficult to implement, and the operational consequences of such change, difficult to predict due to the system s complexity. Some research suggests redistributing air traffic control functions through the system, but this work has largely been dismissed out of hand, accused of being impractical. However, the case for functionally-based reorganization of form can be made from a theoretical, systems perspective. This paper investigates Air Traffic Management functions and their intrinsic biases towards centralized/distributed operations, grounded in systems engineering and information technology theories. Application of these concepts to a small airport operations design is discussed. From this groundwork, a robust, scalable system transformation plan may be made in light of uncertain demand.
Matsui, Daisuke; Nakano, Shogo; Dadashipour, Mohammad; Asano, Yasuhisa
2017-08-25
Insolubility of proteins expressed in the Escherichia coli expression system hinders the progress of both basic and applied research. Insoluble proteins contain residues that decrease their solubility (aggregation hotspots). Mutating these hotspots to optimal amino acids is expected to improve protein solubility. To date, however, the identification of these hotspots has proven difficult. In this study, using a combination of approaches involving directed evolution and primary sequence analysis, we found two rules to help inductively identify hotspots: the α-helix rule, which focuses on the hydrophobicity of amino acids in the α-helix structure, and the hydropathy contradiction rule, which focuses on the difference in hydrophobicity relative to the corresponding amino acid in the consensus protein. By properly applying these two rules, we succeeded in improving the probability that expressed proteins would be soluble. Our methods should facilitate research on various insoluble proteins that were previously difficult to study due to their low solubility.
DOE Office of Scientific and Technical Information (OSTI.GOV)
Sievers, David A.; Lischeske, James J.; Biddy, Mary J.
Solid-liquid separation of intermediate process slurries is required in some process configurations for the conversion of lignocellulosic biomass to transportation fuels. Thermochemically pretreated and enzymatically hydrolyzed corn stover slurries have proven difficult to filter due to formation of very low permeability cakes that are rich in lignin. Treatment of two different slurries with polyelectrolyte flocculant was demonstrated to increase mean particle size and filterability. Filtration flux was greatly improved, and thus scaled filter unit capacity was increased approximately 40-fold compared with unflocculated slurry. Although additional costs were accrued using polyelectrolyte, techno-economic analysis revealed that the increase in filter capacity significantlymore » reduced overall production costs. Fuel production cost at 95% sugar recovery was reduced by $1.35 US per gallon gasoline equivalent for dilute-acid pretreated and enzymatically hydrolyzed slurries and $3.40 for slurries produced using an additional alkaline de-acetylation preprocessing step that is even more difficult to natively filter.« less
STEAM INJECTION REMEDIATION IN FRACTURED BEDROCK AT LORING AIR FORCE BASE
Contaminated groundwater occurs at many Superfund, RCRA, and Brownfields sites. Chlorinated solvents which can form a dense nonaqueous phase (DNAPL) when released to the subsurface can pose an extreme challenge for remediation, as DNAPLs are often difficult to locate and even ha...
Defining Adequacy: Implications for School Business Officials.
ERIC Educational Resources Information Center
Picus, Lawrence O.
1999-01-01
Whereas equity generally focuses on relative levels or distributions of funds, adequacy stresses providing sufficient and absolute funding levels to produce desired student outcomes. Adequacy underlies many recent court decisions. Estimating costs of an adequate education is extremely difficult. School business officials must develop better…
Identification of source-sink dynamics in mountain lions of the Great Basin
USDA-ARS?s Scientific Manuscript database
Understanding population boundaries and movement rates in the field for species that are cryptic and occur at low densities is often extremely difficult and logistically prohibitive; however genetic techniques may offer insights that have previously been unattainable. We analyzed thirteen microsatel...
Field Scale Monitoring and Modeling of Water and Chemical Transfer in the Vadose Zone
USDA-ARS?s Scientific Manuscript database
Natural resource systems involve highly complex interactions of soil-plant-atmosphere-management components that are extremely difficult to quantitatively describe. Computer simulations for prediction and management of watersheds, water supply areas, and agricultural fields and farms have become inc...
2018-04-02
NASA's Solar Dynamics Observatory ran together three sequences of the sun taken in three different extreme ultraviolet wavelengths to better illustrate how different features that appear in one sequence are difficult if not impossible to see in the others (Mar. 20-21, 2018). In the red sequence (304 Angstroms), we can see very small spicules and some small prominences at the sun's edge, which are not easy to see in the other two sequences. In the second clip (193 Angstroms), we can readily observe the large and dark coronal hole, though it is difficult to make out in the others. In the third clip (171 wavelengths), we can see strands of plasma waving above the surface, especially above the one small, but bright, active region near the right edge. And these are just three of the 10 extreme ultraviolet wavelengths in which SDO images the sun every 12 seconds every day. That's a lot of data and a lot of science. Movies are available at https://photojournal.jpl.nasa.gov/catalog/PIA22360
NASA Astrophysics Data System (ADS)
Chu, Hsu-hsin; Wang, Jyhpyng
2018-05-01
Nonlinear optics in the extreme-ultraviolet (EUV) has been limited by lack of transparent media and small conversion efficiency. To overcome this problem we explore the advantage of using multiply charged ion plasmas as the interacting media between EUV and intense near-infrared (NIR) pulses. Such media are transparent to EUV and can withstand intense NIR driving pulses without damage. We calculate the third-order nonlinear polarizabilities of Ar2 + and Ar3 + ions for EUV and NIR four-wave mixing by using the well-proven Cowan code and find that the EUV-to-EUV conversion efficiency as high as 26% can be expected for practical experimental configurations using multi-terawatt NIR lasers. Such a high efficiency is possible because the driving pulse intensity can be scaled up to several orders of magnitude higher than in conventional nonlinear media, and the group-velocity and phase mismatch are insignificant at the experimental plasma densities. This effective scheme of wave mixing can be utilized for ultrafast EUV waveform measurement and control as well as wavelength conversion.
Overview of Key Results from SDO Extreme ultraviolet Variability Experiment (EVE)
NASA Astrophysics Data System (ADS)
Woods, Tom; Eparvier, Frank; Jones, Andrew; Mason, James; Didkovsky, Leonid; Chamberlin, Phil
2016-10-01
The SDO Extreme ultraviolet Variability Experiment (EVE) includes several channels to observe the solar extreme ultraviolet (EUV) spectral irradiance from 1 to 106 nm. These channels include the Multiple EUV Grating Spectrograph (MEGS) A, B, and P channels from the University of Colorado (CU) and the EUV SpectroPhometer (ESP) channels from the University of Southern California (USC). The solar EUV spectrum is rich in many different emission lines from the corona, transition region, and chromosphere. The EVE full-disk irradiance spectra are important for studying the solar impacts in Earth's ionosphere and thermosphere and are useful for space weather operations. In addition, the EVE observations, with its high spectral resolution of 0.1 nm and in collaboration with AIA solar EUV images, have proven valuable for studying active region evolution and explosive energy release during flares and coronal eruptions. These SDO measurements have revealed interesting results such as understanding the flare variability over all wavelengths, discovering and classifying different flare phases, using coronal dimming measurements to predict CME properties of mass and velocity, and exploring the role of nano-flares in continual heating of active regions.
Brain natriuretic peptide-guided therapy in the inpatient management of decompensated heart failure.
Saremi, Adonis; Gopal, Dipika; Maisel, Alan S
2012-02-01
Heart failure is extremely prevalent and is associated with significant mortality, morbidity and cost. Studies have already established mortality benefit with the use of neurohormonal blockade therapy in systolic failure. Unfortunately, physical signs and symptoms of heart failure lack diagnostic sensitivity and specificity, and medication doses proven to improve mortality in clinical trials are often not achieved. Brain natriuretic peptide (BNP) has proven to be of clinical use in the diagnosis and prognosis of heart failure, and recent efforts have been taken to further elucidate its role in guiding heart failure management. Multiple studies have been conducted on outpatient guided management, and although still controversial, there is a trend towards improved outcomes. Inpatient studies are lacking, but preliminary data suggest various BNP cut-off values, as well as percentage changes in BNP, that could be useful in predicting outcomes and improving mortality. In the future, heart failure management will probably involve an algorithm using clinical assessment and a multibiomarker-guided approach.
NASA Astrophysics Data System (ADS)
Pennington, D. D.; Garnica Chavira, L.; Villanueva-Rosales, N.
2017-12-01
People living in the vicinity of the middle Rio Grande from Elephant Butte Reservoir in New Mexico through Fort Quitman, Texas, including inhabitants on the Mexican side of the river, are confronted with numerous challenges that include drought, population growth, reduced surface water quality and quantity, declining aquifers, and expected future increases in temperature with more variable precipitation. The transboundary surface water is subject to complex regulation across two U.S. states and two nations (U.S. and Mexico). This presentation will summarize the modeling efforts of a USDA-funded project to characterize potential future solutions for water sustainability while managing agriculture, economic, and human impacts. It will present an online software system designed for rapid, flexible modeling of different climate, policy, and technology scenarios with stakeholders, and the underlying intelligent system that manages model selection, data and parameters, and user choices, and provides a provenance trace based on the W3C PROV standard.
The Analytic Hierarchy Process and Participatory Decisionmaking
Daniel L. Schmoldt; Daniel L. Peterson; Robert L. Smith
1995-01-01
Managing natural resource lands requires social, as well as biophysical, considerations. Unfortunately, it is extremely difficult to accurately assess and quantify changing social preferences, and to aggregate conflicting opinions held by diverse social groups. The Analytic Hierarchy Process (AHP) provides a systematic, explicit, rigorous, and robust mechanism for...
USDA-ARS?s Scientific Manuscript database
Gardner saltbush ecosystems are increasingly being invaded by halogeton (Halogeton glomeratus), which is extremely competitive and believed to increase soil surface salinity making it difficult to establish other desired plants. This study evaluated the ability of forage kochia (Kochia prostrata), ...
ERIC Educational Resources Information Center
Van Der Werf, Martin
2007-01-01
As the number of American students studying overseas increases, it will be difficult for colleges to establish or find enough adequate programs with challenging curricula. Students desire ever more remote locations, and colleges are being pushed to support the extremely adventurous. With more students studying abroad, and amid heightened fears…
"Vulnerable Families": Reflections on a Difficult Category
ERIC Educational Resources Information Center
Bauer, Petra; Wiezorek, Christine
2016-01-01
The term "vulnerable families" refers to familial living situations that are considered problematic, with a particular need for socially responsible, professionally provided support. This means of categorising families is extremely ambivalent, indicating not only a need for society to support forms of family life and family achievements,…
The extremely high exposure levels evaluated in prior investigations relating elevated levels of drinking water arsenic and hypertension prevalence make extrapolation to potential vascular effects at lower exposure levels very difficult. A cross-sectional study was conducted on ...
Measurements of n-octanol/water partition coefficients (KOW) for highly hydrophobic chemicals, i.e., greater than 108, are extremely difficult and are rarely made, in part because the vanishingly small concentrations in the water phase require extraordinary analytical sensitivity...
Sex Work Research: Methodological and Ethical Challenges
ERIC Educational Resources Information Center
Shaver, Frances M.
2005-01-01
The challenges involved in the design of ethical, nonexploitative research projects with sex workers or any other marginalized population are significant. First, the size and boundaries of the population are unknown, making it extremely difficult to get a representative sample. Second, because membership in hidden populations often involves…
Development of Semiochemical Based Control Programs for Arthropod Pests of Honeybees
USDA-ARS?s Scientific Manuscript database
In recent years the apiculture industry has experienced serious problems from serious invasions by exotic pests including Varroa destructor and the Small hive beetle, Aethina tumida. Control of these pests is difficult and problematic because Honey bees are extremely sensitive to pesticides and the...
Geiger, Stephen C; Azzolina, Nicholas A; Nakles, David V; Hawthorne, Steven B
2016-07-01
Polycyclic aromatic hydrocarbons (PAHs) are major drivers of risk at many urban and/or industrialized sediment sites. The US Environmental Protection Agency (USEPA) currently recommends using measurements of 18 parent + 16 groups of alkylated PAHs (PAH-34) to assess the potential for sediment-bound PAHs to impact benthic organisms at these sites. ASTM Method D7363-13 was developed to directly measure low-level sediment porewater PAH concentrations. These concentrations are then compared to ambient water criteria (final chronic values [FCVs]) to assess the potential for impact to benthic organisms. The interlaboratory validation study that was used to finalize ASTM D7363-13 was developed using 24 of the 2-, 3-, and 4-ring PAHs (PAH-24) that are included in the USEPA PAH-34 analyte list. However, it is the responsibility of the user of ASTM Method D7363 to establish a test method to quantify the remaining 10 higher molecular weight PAHs that make up PAH-34. These higher molecular weight PAHs exhibit extremely low saturation solubilities that make their detection difficult in porewater, which has proven difficult to implement in a contract laboratory setting. As a result, commercial laboratories are hesitant to conduct the method on the entire PAH-34 analyte list. This article presents a statistical comparison of the ability of the PAH-24 and PAH-34 porewater results to predict survival of the freshwater amphipod Hyalella azteca, using the original 269 sediment samples used to gain ASTM D7363 Method approval. The statistical analysis shows that the PAH-24 are statistically indistinguishable from the PAH-34 for predicting toxicity. These results indicate that the analysis of freely dissolved porewater PAH-24 is sufficient for making risk-based decisions based on benthic invertebrate toxicity (survival and growth). This reduced target analyte list should result in a cost-saving for stakeholders and broader implementation of the method at PAH-impacted sediment sites. Integr Environ Assess Manag 2016;12:493-499. © 2015 SETAC. © 2015 SETAC.
A Method for Aircraft Concept Selection Using Multicriteria Interactive Genetic Algorithms
NASA Technical Reports Server (NTRS)
Buonanno, Michael; Mavris, Dimitri
2005-01-01
The problem of aircraft concept selection has become increasingly difficult in recent years as a result of a change from performance as the primary evaluation criteria of aircraft concepts to the current situation in which environmental effects, economics, and aesthetics must also be evaluated and considered in the earliest stages of the decision-making process. This has prompted a shift from design using historical data regression techniques for metric prediction to the use of physics-based analysis tools that are capable of analyzing designs outside of the historical database. The use of optimization methods with these physics-based tools, however, has proven difficult because of the tendency of optimizers to exploit assumptions present in the models and drive the design towards a solution which, while promising to the computer, may be infeasible due to factors not considered by the computer codes. In addition to this difficulty, the number of discrete options available at this stage may be unmanageable due to the combinatorial nature of the concept selection problem, leading the analyst to arbitrarily choose a sub-optimum baseline vehicle. These concept decisions such as the type of control surface scheme to use, though extremely important, are frequently made without sufficient understanding of their impact on the important system metrics because of a lack of computational resources or analysis tools. This paper describes a hybrid subjective/quantitative optimization method and its application to the concept selection of a Small Supersonic Transport. The method uses Genetic Algorithms to operate on a population of designs and promote improvement by varying more than sixty parameters governing the vehicle geometry, mission, and requirements. In addition to using computer codes for evaluation of quantitative criteria such as gross weight, expert input is also considered to account for criteria such as aeroelasticity or manufacturability which may be impossible or too computationally expensive to consider explicitly in the analysis. Results indicate that concepts resulting from the use of this method represent designs which are promising to both the computer and the analyst, and that a mapping between concepts and requirements that would not otherwise be apparent is revealed.
Vector autoregressive models: A Gini approach
NASA Astrophysics Data System (ADS)
Mussard, Stéphane; Ndiaye, Oumar Hamady
2018-02-01
In this paper, it is proven that the usual VAR models may be performed in the Gini sense, that is, on a ℓ1 metric space. The Gini regression is robust to outliers. As a consequence, when data are contaminated by extreme values, we show that semi-parametric VAR-Gini regressions may be used to obtain robust estimators. The inference about the estimators is made with the ℓ1 norm. Also, impulse response functions and Gini decompositions for prevision errors are introduced. Finally, Granger's causality tests are properly derived based on U-statistics.
[Ultrasound scattering properties of Albunex microspheres].
Takamoto, T; Shiina, T
1998-04-01
In Japan, clinical and basic investigations of Albunex were started from 1989, and was firstly approved by the government as a commercially available contrast agent for the cardiovascular disorders. Although it has recently evacuated from the market, its acoustic properties proven by the many investigators were valuable for preparation of the second generation of contrast agents. Therefore, we summarized our data of the ultrasonic properties of Albunex both in vitro and experimental dog studies using RF signals. In conclusion, Albunex was a extremely sensitive blood flow tracer in evaluating intracardiac blood flow as well as intramyocardial perfusion.
Generation of Stable Knockout Mammalian Cells by TALEN-Mediated Locus-Specific Gene Editing.
Mahata, Barun; Biswas, Kaushik
2017-01-01
Precise and targeted genome editing using Transcription Activator-Like Effector Endonucleases (TALENs) has been widely used and proven to be an extremely effective and specific knockout strategy in both cultured cells and animal models. The current chapter describes a protocol for the construction and generation of TALENs using serial and hierarchical digestion and ligation steps, and using the synthesized TALEN pairs to achieve locus-specific targeted gene editing in mammalian cell lines using a modified clonal selection strategy in an easy and cost-efficient manner.
NASA Astrophysics Data System (ADS)
Schoeppner, M.; Plastino, W.; Budano, A.; De Vincenzi, M.; Ruggieri, F.
2012-04-01
Several nuclear reactors at the Fukushima Dai-ichi power plant have been severely damaged from the Tōhoku earthquake and the subsequent tsunami in March 2011. Due to the extremely difficult on-site situation it has been not been possible to directly determine the emissions of radioactive material. However, during the following days and weeks radionuclides of 137-Caesium and 131-Iodine (amongst others) were detected at monitoring stations throughout the world. Atmospheric transport models are able to simulate the worldwide dispersion of particles accordant to location, time and meteorological conditions following the release. The Lagrangian atmospheric transport model Flexpart is used by many authorities and has been proven to make valid predictions in this regard. The Flexpart software has first has been ported to a local cluster computer at the Grid Lab of INFN and Department of Physics of University of Roma Tre (Rome, Italy) and subsequently also to the European Mediterranean Grid (EUMEDGRID). Due to this computing power being available it has been possible to simulate the transport of particles originating from the Fukushima Dai-ichi plant site. Using the time series of the sampled concentration data and the assumption that the Fukushima accident was the only source of these radionuclides, it has been possible to estimate the time-dependent source-term for fourteen days following the accident using the atmospheric transport model. A reasonable agreement has been obtained between the modelling results and the estimated radionuclide release rates from the Fukushima accident.
Task-Specific Response Strategy Selection on the Basis of Recent Training Experience
Fulvio, Jacqueline M.; Green, C. Shawn; Schrater, Paul R.
2014-01-01
The goal of training is to produce learning for a range of activities that are typically more general than the training task itself. Despite a century of research, predicting the scope of learning from the content of training has proven extremely difficult, with the same task producing narrowly focused learning strategies in some cases and broadly scoped learning strategies in others. Here we test the hypothesis that human subjects will prefer a decision strategy that maximizes performance and reduces uncertainty given the demands of the training task and that the strategy chosen will then predict the extent to which learning is transferable. To test this hypothesis, we trained subjects on a moving dot extrapolation task that makes distinct predictions for two types of learning strategy: a narrow model-free strategy that learns an input-output mapping for training stimuli, and a general model-based strategy that utilizes humans' default predictive model for a class of trajectories. When the number of distinct training trajectories is low, we predict better performance for the mapping strategy, but as the number increases, a predictive model is increasingly favored. Consonant with predictions, subject extrapolations for test trajectories were consistent with using a mapping strategy when trained on a small number of training trajectories and a predictive model when trained on a larger number. The general framework developed here can thus be useful both in interpreting previous patterns of task-specific versus task-general learning, as well as in building future training paradigms with certain desired outcomes. PMID:24391490
Clinical follow up of uniparental disomy 16: First data
DOE Office of Scientific and Technical Information (OSTI.GOV)
Dworniczak, B.; Koppers, B.; Bogdanova, N.
1994-09-01
Following the introduction of the concept of uniparental disomy (UPD) in 1980 by Engel this segregational anomaly is reported in an ever increasing number of patients. So far, several groups of individuals with an increased risk for UPD have been identified including abnormal carriers of familial balanced translocations or centric fusions, carriers of mosaic trisomies, and fetuses after prenatal diagnosis of confined placental mosaicism. A major pathogenetic mechanism appears to be post-meiotic chromosome loss in trisomic conceptuses. UPD was repeatedly observed in the fetus after diagnosis of mosaic or non-mosaic trisomies in the placenta which are usually considered {open_quotes}lethal{close_quotes} (i.e.more » trisomies 15 and 16). In an ongoing study to determine the incidence and clinical consequences of UPD we investigated the parental origin of chromosomes in the disomic cell line after prenatal diagnosis of mosaicism for various trisomies (e.g. 2, 7, 14, 15, and 16). At present, two maternal disomies 16 and one maternal disomy 15 were identified. Severe intrauterine growth retardation was a common symptome which, however, was also present in some but not all mosaics with a biparental origin of the chromosomes in question. While prognosis is clear in some instances (i.e. UPD 15) counseling can be extremely difficult in others, when imprinting effects and homozygosity for unknown recessive traits present in a parent have to be considered. To assess the clinical significance, detailed follow-up studies of proven cases of uniparental disomies are essential. First data of two cases with UPD 16 are presented.« less
Experimental validation of numerical simulations on a cerebral aneurysm phantom model
Seshadhri, Santhosh; Janiga, Gábor; Skalej, Martin; Thévenin, Dominique
2012-01-01
The treatment of cerebral aneurysms, found in roughly 5% of the population and associated in case of rupture to a high mortality rate, is a major challenge for neurosurgery and neuroradiology due to the complexity of the intervention and to the resulting, high hazard ratio. Improvements are possible but require a better understanding of the associated, unsteady blood flow patterns in complex 3D geometries. It would be very useful to carry out such studies using suitable numerical models, if it is proven that they reproduce accurately enough the real conditions. This validation step is classically based on comparisons with measured data. Since in vivo measurements are extremely difficult and therefore of limited accuracy, complementary model-based investigations considering realistic configurations are essential. In the present study, simulations based on computational fluid dynamics (CFD) have been compared with in situ, laser-Doppler velocimetry (LDV) measurements in the phantom model of a cerebral aneurysm. The employed 1:1 model is made from transparent silicone. A liquid mixture composed of water, glycerin, xanthan gum and sodium chloride has been specifically adapted for the present investigation. It shows physical flow properties similar to real blood and leads to a refraction index perfectly matched to that of the silicone model, allowing accurate optical measurements of the flow velocity. For both experiments and simulations, complex pulsatile flow waveforms and flow rates were accounted for. This finally allows a direct, quantitative comparison between measurements and simulations. In this manner, the accuracy of the employed computational model can be checked. PMID:24265876
Genome-based Modeling and Design of Metabolic Interactions in Microbial Communities
Mahadevan, Radhakrishnan; Henson, Michael A.
2012-01-01
Biotechnology research is traditionally focused on individual microbial strains that are perceived to have the necessary metabolic functions, or the capability to have these functions introduced, to achieve a particular task. For many important applications, the development of such omnipotent microbes is an extremely challenging if not impossible task. By contrast, nature employs a radically different strategy based on synergistic combinations of different microbial species that collectively achieve the desired task. These natural communities have evolved to exploit the native metabolic capabilities of each species and are highly adaptive to changes in their environments. However, microbial communities have proven difficult to study due to a lack of suitable experimental and computational tools. With the advent of genome sequencing, omics technologies, bioinformatics and genome-scale modeling, researchers now have unprecedented capabilities to analyze and engineer the metabolism of microbial communities. The goal of this review is to summarize recent applications of genome-scale metabolic modeling to microbial communities. A brief introduction to lumped community models is used to motivate the need for genome-level descriptions of individual species and their metabolic interactions. The review of genome-scale models begins with static modeling approaches, which are appropriate for communities where the extracellular environment can be assumed to be time invariant or slowly varying. Dynamic extensions of the static modeling approach are described, and then applications of genome-scale models for design of synthetic microbial communities are reviewed. The review concludes with a summary of metagenomic tools for analyzing community metabolism and an outlook for future research. PMID:24688668
Koenig, Thomas W; Parrish, Samuel K; Terregino, Carol A; Williams, Joy P; Dunleavy, Dana M; Volsch, Joseph M
2013-05-01
Assessing applicants' personal competencies in the admission process has proven difficult because there is not an agreed-on set of personal competencies for entering medical students. In addition, there are questions about the measurement properties and costs of currently available assessment tools. The Association of American Medical College's Innovation Lab Working Group (ILWG) and Admissions Initiative therefore engaged in a multistep, multiyear process to identify personal competencies important to entering students' success in medical school as well as ways to measure them early in the admission process. To identify core personal competencies, they conducted literature reviews, surveyed U.S and Canadian medical school admission officers, and solicited input from the admission community. To identify tools with the potential to provide data in time for pre-interview screening, they reviewed the higher education and employment literature and evaluated tools' psychometric properties, group differences, risk of coaching/faking, likely applicant and admission officer reactions, costs, and scalability. This process resulted in a list of nine core personal competencies rated by stakeholders as very or extremely important for entering medical students: ethical responsibility to self and others; reliability and dependability; service orientation; social skills; capacity for improvement; resilience and adaptability; cultural competence; oral communication; and teamwork. The ILWG's research suggests that some tools hold promise for assessing personal competencies, but the authors caution that none are perfect for all situations. They recommend that multiple tools be used to evaluate information about applicants' personal competencies in deciding whom to interview.
Genome-based Modeling and Design of Metabolic Interactions in Microbial Communities.
Mahadevan, Radhakrishnan; Henson, Michael A
2012-01-01
Biotechnology research is traditionally focused on individual microbial strains that are perceived to have the necessary metabolic functions, or the capability to have these functions introduced, to achieve a particular task. For many important applications, the development of such omnipotent microbes is an extremely challenging if not impossible task. By contrast, nature employs a radically different strategy based on synergistic combinations of different microbial species that collectively achieve the desired task. These natural communities have evolved to exploit the native metabolic capabilities of each species and are highly adaptive to changes in their environments. However, microbial communities have proven difficult to study due to a lack of suitable experimental and computational tools. With the advent of genome sequencing, omics technologies, bioinformatics and genome-scale modeling, researchers now have unprecedented capabilities to analyze and engineer the metabolism of microbial communities. The goal of this review is to summarize recent applications of genome-scale metabolic modeling to microbial communities. A brief introduction to lumped community models is used to motivate the need for genome-level descriptions of individual species and their metabolic interactions. The review of genome-scale models begins with static modeling approaches, which are appropriate for communities where the extracellular environment can be assumed to be time invariant or slowly varying. Dynamic extensions of the static modeling approach are described, and then applications of genome-scale models for design of synthetic microbial communities are reviewed. The review concludes with a summary of metagenomic tools for analyzing community metabolism and an outlook for future research.
Stress Fractures of the Foot and Ankle in Athletes
Mayer, Stephanie W.; Joyner, Patrick W.; Almekinders, Louis C.; Parekh, Selene G.
2014-01-01
Context: Stress fractures of the foot and ankle are a common problem encountered by athletes of all levels and ages. These injuries can be difficult to diagnose and may be initially evaluated by all levels of medical personnel. Clinical suspicion should be raised with certain history and physical examination findings. Evidence Acquisition: Scientific and review articles were searched through PubMed (1930-2012) with search terms including stress fractures and 1 of the following: foot ankle, medial malleolus, lateral malleolus, calcaneus, talus, metatarsal, cuboid, cuneiform, sesamoid, or athlete. Study Design: Clinical review. Level of Evidence: Level 5. Results: Stress fractures of the foot and ankle can be divided into low and high risk based upon their propensity to heal without complication. A wide variety of nonoperative strategies are employed based on the duration of symptoms, type of fracture, and patient factors, such as activity type, desire to return to sport, and compliance. Operative management has proven superior in several high-risk types of stress fractures. Evidence on pharmacotherapy and physiologic therapy such as bone stimulators is evolving. Conclusion: A high index of suspicion for stress fractures is appropriate in many high-risk groups of athletes with lower extremity pain. Proper and timely work-up and treatment is successful in returning these athletes to sport in many cases. Low-risk stress fracture generally requires only activity modification while high-risk stress fracture necessitates more aggressive intervention. The specific treatment of these injuries varies with the location of the stress fracture and the goals of the patient. PMID:25364480
Regioselective Synthesis of Cellulose Ester Homopolymers
Daiqiang Xu; Kristen Voiges; Thomas Elder; Petra Mischnick; Kevin J. Edgar
2012-01-01
Regioselective synthesis of cellulose esters is extremely difficult due to the small reactivity differences between cellulose hydroxyl groups, small differences in steric demand between acyl moieties of interest, and the difficulty of attaching and detaching many protecting groups in the presence of cellulose ester moieties without removing the ester groups. Yet the...
Phosphorus (P) remediation is an extremely difficult and costly environmental problem and could cost $44.5 billion for treatment using conventional water treatment plants to meet EPA requirements. Phosphorus runoffs can lead to dead zones due to eutrophication and also ca...
Working with Child Prostitutes in Thailand: Problems of Practice and Interpretation
ERIC Educational Resources Information Center
Montgomery, Heather
2007-01-01
Conducting anthropological fieldwork on the emotive issue of child prostitution raises difficult issues for anthropologists and other researchers. This article examines the ethical dilemmas of working with these extremely vulnerable children, focusing on the difference between the researcher's own interpretations and those given by the children…
Guidelines to Support Professional Copyright Practice
ERIC Educational Resources Information Center
Dryden, Jean
2012-01-01
Copyright is extremely complex, and it is difficult to convey its complexities in a clear and concise form. Through decades of experience, archivists developed informal best practices for dealing with copyright in the analog world; however the application of copyright in the digital environment is evolving in response to rapidly changing…
Educational Management within a Young Offender Institution.
ERIC Educational Resources Information Center
Fryer, Winny; Fryer, Paul
1992-01-01
Examines educational theory and objectives within prisons and relates these to the real-time case study of the Young Offender Institution at Whatton, in Nottinghamshire, England. Measuring success and cost effectiveness is extremely difficult in the prison education field, and a significant gap exists between the theoretical model and everyday…
Accountability: Its Implications for Provincial and State Governments.
ERIC Educational Resources Information Center
Kolesar, H.
This paper examines the implications of the accountability concept for provincial or State authorities. Accountability is defined as a concomitant of an agreement between two parties. The author suggests that, in education, agreements between parties have lacked preciseness and clarity, making it extremely difficult to assess performance and to…
The American Indian: A Very Private People.
ERIC Educational Resources Information Center
Chan, Carole; Hamby, John
American Indian urban immigration has put between 33% and 50% of all Indians in urban settings where they invariably are subjected to an initial cultural shock. Leaving the reservation to improve their socioeconomic status, Indians find urban adjustment extremely difficult. The Anglo culture is inherently opposed to the "Indian Way", for it…
Creating 3D Physical Models to Probe Student Understanding of Macromolecular Structure
ERIC Educational Resources Information Center
Cooper, A. Kat; Oliver-Hoyo, M. T.
2017-01-01
The high degree of complexity of macromolecular structure is extremely difficult for students to process. Students struggle to translate the simplified two-dimensional representations commonly used in biochemistry instruction to three-dimensional aspects crucial in understanding structure-property relationships. We designed four different physical…
A Zone for Deliberation? Methodological Challenges in Fields of Political Unrest
ERIC Educational Resources Information Center
Westrheim, Kariane; Lillejord, Solvi
2007-01-01
This article outlines certain problems and challenges facing the qualitative researcher who enters fields that are either extremely difficult to access or potentially hostile towards outsiders. Problems and dilemmas in such contexts are highlighted by reference to fieldwork research among PKK (Kurdistan Worker's Party) guerrillas in North…
DOT National Transportation Integrated Search
1973-01-01
It was found that valid predictions of the use of containers were extremely difficult to make because of the lack of reliable data. Further, during the time of the study, the local ports negotiated for international consolidation, the dollar was deva...
From Positive Reinforcement to Positive Behaviors: An Everyday Guide for the Practitioner
ERIC Educational Resources Information Center
Sigler, Ellen A.; Aamidor, Shirley
2005-01-01
There are various opinions concerning the value of positive reinforcement when discussing modifying behaviors of young children. In some cases, individuals considered positive reinforcement difficult to implement and, in extreme cases, even felt it to be detrimental. Educators often use praise interchangeably with positive reinforcement when…
U.S. National Security Policy. Revision.
1986-03-01
World War II, Sino-American relations have fluctuated from tacit war (in the early 1950s) to a quasi alliance (in the late 1970s). This .I historical ... volatility makes prediction of the long-term future extremely difficult, but the character of Chinese foreign policy in 2010 well may be (after the
Changing University Students' Alternative Conceptions of Optics by Active Learning
ERIC Educational Resources Information Center
Hadžibegovic, Zalkida; Sliško, Josip
2013-01-01
Active learning is individual and group participation in effective activities such as in-class observing, writing, experimenting, discussion, solving problems, and talking about to-be-learned topics. Some instructors believe that active learning is impossible, or at least extremely difficult to achieve in large lecture sessions. Nevertheless, the…
Improving Professional Judgments of Risk and Amenability in Juvenile Justice
ERIC Educational Resources Information Center
Mulvey, Edward P.; Iselin, Anne-Marie R.
2008-01-01
The dual requirement to ensure community safety and promote a youthful offender's positive development permeates policy and frames daily practice in juvenile justice. Balancing those two demands, explain Edward Mulvey and Anne-Marie Iselin, requires justice system professionals at all levels to make extremely difficult decisions about the likely…
EVALUATING CUMULATIVE EFFECTS OF DISTURBANCE ON THE HYDROLOGIC FUNCTION OF BOGS, FENS, AND MIRES
Few quantitative studies have been done on the hydrology of fens, bogs and mires, and consequently any predictions of the cumulative impacts of disturbances on their hydrologic functions is extremely difficult. or example, few data are available on the role of bogs and fens with ...
ERIC Educational Resources Information Center
Williams, Kathryn R.
2007-01-01
The safety and health hazards related to recycling of used rubber, due to the scarcity and high price of virgin rubber are reported. Various threats like stagnant water pools trapped in tires leading to diseases and ignited tires, which become very difficult to extinguish and generating smoke that is extremely detrimental to the environment, have…
Sowing pregerminated northern red oak acorns
Richard M. Godman; Gilbert A. Mattson
1992-01-01
Northern red oak is extremely difficult to regenerate, although it has produced good acorn crops nearly half of the last 32 years in northern Wisconsin. Field trials have shown that for successful seeding, you must protect acorns from predation by wildlife and sow them when temperatures are most favorable for germination.
Estimating timber supply from private forests
D.F. Dennis
1991-01-01
Nonindustrial private landowners, who hold a majority of the Nation's commercial forests, own land primarily for reasons other than timber production. The multiple objective and dynamic nature of private ownership make planning and estimation of timber availability from this sector extremely difficult. Insight into the determinants of timber supply from private...
Challenges Facing Guitar Education
ERIC Educational Resources Information Center
Harrison, Eli
2010-01-01
The guitar is an extremely versatile instrument. It can produce complex chords and arpeggiated textures as readily as single-note melodies. In the twentieth century alone, it has appeared in a wide range of genres; classical, jazz, blues, rock, and bossa nova compose a partial list. The guitar is also a difficult instrument. Inconsistencies across…
Education: Perceiving the Disease and Prescribing the Remedy
ERIC Educational Resources Information Center
Clarken, Rodney H.
2007-01-01
Modern thinkers chiefly identify development with materialistic and economic factors. Education is often measured and evaluated by the same standard: its material and economic impact on the individual and society. A moral balance is recommended to this excessively materialistic perspective. It is extremely difficult to unravel the complexities of…
Employment Problems of the Vietnam Veteran. Special Report.
ERIC Educational Resources Information Center
National Advisory Council on Vocational Education, Washington, DC.
Vietnam veterans are finding it extremely difficult of find jobs upon their return home. Altogether there are approximately 320,000 known unemployed veterans. Statistics show that they have a higher unemployment rate than nonveterans, and that the unemployment persists longer. Factors contributing to this condition are the economic slump, a…
Wind Tunnel Data Fusion and Immersive Visualization: A Case Study
NASA Technical Reports Server (NTRS)
Severance, Kurt; Brewster, Paul; Lazos, Barry; Keefe, Daniel
2001-01-01
This case study describes the process of fusing the data from several wind tunnel experiments into a single coherent visualization. Each experiment was conducted independently and was designed to explore different flow features around airplane landing gear. In the past, it would have been very difficult to correlate results from the different experiments. However, with a single 3-D visualization representing the fusion of the three experiments, significant insight into the composite flowfield was observed that would have been extremely difficult to obtain by studying its component parts. The results are even more compelling when viewed in an immersive environment.
Better Redd than Dead: Optimizing Reservoir Operations for Wild Fish Survival During Drought
NASA Astrophysics Data System (ADS)
Adams, L. E.; Lund, J. R.; Quiñones, R.
2014-12-01
Extreme droughts are difficult to predict and may incur large economic and ecological costs. Dam operations in drought usually consider minimizing economic costs. However, dam operations also offer an opportunity to increase wild fish survival under difficult conditions. Here, we develop a probabilistic optimization approach to developing reservoir release schedules to maximize fish survival in regulated rivers. A case study applies the approach to wild Fall-run Chinook Salmon below Folsom Dam on California's American River. Our results indicate that releasing more water early in the drought will, on average, save more wild fish over the long term.
Ülker, Kahraman; Akyer, Şahika P; Temur, İsmail; Tan, Temel; Karaca, Mehmet; Adıgüzel, Esat; Gül, Abdülaziz
2012-02-01
Parapagus (laterally fused), diprosopus (two faces), dibrachius (two upper extremities), dipus (two lower extremities) conjoined twinning is extremely rare. The coexistence of anencephaly with a contiguous spinal defect (craniorachischisis totalis) makes the present case one of the rarest of the published cases. In our case, it was difficult to make the final diagnosis by two-dimensional abdominal and vaginal ultrasound. Three-dimensional ultrasound was helpful for final diagnosis and post-abortal examination confirmed the prenatal ultrasound diagnosis. The heart, diaphragm, liver and perineum were all united. Fine dissection of the heart showed four vessels arising from the ventricles and a membranous type ventricular septal defect. © 2011 The Authors. Journal of Obstetrics and Gynaecology Research © 2011 Japan Society of Obstetrics and Gynecology.
Extreme hydronephrosis due to uretropelvic junction obstruction in infant (case report).
Krzemień, Grażyna; Szmigielska, Agnieszka; Bombiński, Przemysław; Barczuk, Marzena; Biejat, Agnieszka; Warchoł, Stanisław; Dudek-Warchoł, Teresa
2016-01-01
Hydronephrosis is the one of the most common congenital abnormalities of urinary tract. The left kidney is more commonly affected than the right side and is more common in males. To determine the role of ultrasonography, renal dynamic scintigraphy and lowerdose computed tomography urography in preoperative diagnostic workup of infant with extreme hydronephrosis. We presented the boy with antenatally diagnosed hydronephrosis. In serial, postnatal ultrasonography, renal scintigraphy and computed tomography urography we observed slightly declining function in the dilated kidney and increasing pelvic dilatation. Pyeloplasty was performed at the age of four months with good result. Results of ultrasonography and renal dynamic scintigraphy in child with extreme hydronephrosis can be difficult to asses, therefore before the surgical procedure a lower-dose computed tomography urography should be performed.
Dismounted Complex Blast Injury.
Andersen, Romney C; Fleming, Mark; Forsberg, Jonathan A; Gordon, Wade T; Nanos, George P; Charlton, Michael T; Ficke, James R
2012-01-01
The severe Dismounted Complex Blast Injury (DCBI) is characterized by high-energy injuries to the bilateral lower extremities (usually proximal transfemoral amputations) and/or upper extremity (usually involving the non-dominant side), in addition to open pelvic injuries, genitourinary, and abdominal trauma. Initial resuscitation and multidisciplinary surgical management appear to be the keys to survival. Definitive treatment follows general principals of open wound management and includes decontamination through aggressive and frequent debridement, hemorrhage control, viable tissue preservation, and appropriate timing of wound closure. These devastating injuries are associated with paradoxically favorable survival rates, but associated injuries and higher amputation levels lead to more difficult reconstructive challenges.
Phase transitions and dynamics of bulk and interfacial water.
Franzese, G; Hernando-Martínez, A; Kumar, P; Mazza, M G; Stokely, K; Strekalova, E G; de los Santos, F; Stanley, H E
2010-07-21
New experiments on water at the surface of proteins at very low temperature display intriguing dynamic behaviors. The extreme conditions of these experiments make it difficult to explore the wide range of thermodynamic state points needed to offer a suitable interpretation. Detailed simulations suffer from the same problem, where equilibration times at low temperature become extremely long. We show how Monte Carlo simulations and mean field calculations using a tractable model of water help interpret the experimental results. Here we summarize the results for bulk water and investigate the thermodynamic and dynamic properties of supercooled water at an interface.
Creating a comprehensive quality-controlled dataset of severe weather occurrence in Europe
NASA Astrophysics Data System (ADS)
Groenemeijer, P.; Kühne, T.; Liang, Z.; Holzer, A.; Feuerstein, B.; Dotzek, N.
2010-09-01
Ground-truth quality-controlled data on severe weather occurrence is required for meaningful research on severe weather hazards. Such data are collected by observation networks of several authorities in Europe, most prominently the National Hydrometeorological Institutes (NHMS). However, some events challenge the capabilities of such conventional networks by their isolated and short-lived nature. These rare and very localized but extreme events include thunderstorm wind gusts, large hail and tornadoes and are poorly resolved by synoptic observations. Moreover, their detection by remote-sensing techniques such as radar and satellites is in development and has proven to be difficult. Using the fact that all across across Europe there are many people with a special personal or professional interest in such events, who are typically organized in associations, allows pursuing a different strategy. Data delivered to the European Severe Weather Database is recorded and quality controlled by ESSL and a large number of partners including the Hydrometeorological Institutes of Germany, Finland, Austria, Italy and Bulgaria. Additionally, nine associations of storm spotters and centres of expertise in these and other countries are involved. The two categories of organizations (NHMSes/other) each have different privileges in the quality control procedure, which involves assigning a quality level of QC0+ (plausibility checked), QC1 (confirmed by reliable sources) or QC2 (verified) to each of the reports. Within the EWENT project funded by the EU 7th framework programme, the RegioExakt project funded by the German Ministry of Education and Research, and with support from the German Weather Service (DWD), several enhancements of the ESWD have been and will be carried out. Completed enhancements include the creation of an interface that allows partner organizations to upload data automatically, in the case of our German partner "Skywarn Germany" in near-real time. Moreover, the database's web-interface has been translated into 14 European languages. At the time of writing, a nowcast-mode to the web interface, which renders the ESWD a convenient tool for meteorologists in forecast centres, is being developed. In the near future, within the EWENT project, an extension of the data set with several other isolated but extreme events including avalanches, landslides, heavy snowfall and extremely powerful lightning flashes, is foreseen. The resulting ESWD dataset, that grows at a rate of 4000-5000 events per year, is used for wide range of purposes including the validation of remote-sensing techniques, forecast verification studies, projections of the future severe storm climate, and risk assessments. Its users include scientists working for EUMETSAT, NASA, NSSL, DLR, and several reinsurance companies.
Strifling, Kelly M B; Konop, Katherine A; Wang, Mei; Harris, Gerald F
2009-01-01
Walkers are prescribed with the notion that one type of walker will be better for a child than another. One underlying justification for this practice is the theory that one walker may produce less stress on the upper extremities as the patient uses the walker. Nevertheless, upper extremity joint loading is not typically analyzed during walker assisted gait in children with spastic diplegic cerebral palsy. It has been difficult to evaluate the theory of walker prescription based on upper extremity stresses because loading on the upper extremities however has not been quantified until recently. In this study, weight bearing on the glenohumeral joints was analyzed in five children with spastic diplegic cerebral palsy using both anterior and posterior walkers fitted with 6-axis handle transducers. Though walkers' effects on the upper extremities proved to be similar between walker types, the differences between the walkers may have some clinical significance in the long run. In general, posterior walker use created larger glenohumeral joint forces. Though these differences are not statistically significant, over time and with repetitive loading they may be clinically significant.
Guimaraes, Julio Brandao; Zanoteli, Edmar; Link, Thomas M; de Camargo, Leonardo V; Facchetti, Luca; Nardo, Lorenzo; Fernandes, Artur da Rocha Correa
2017-12-01
The purpose of this prospective study is to assess MRI findings in patients with sporadic inclusion body myositis (IBM) and correlate them with clinical and functional parameters. This study included 12 patients with biopsy-proven sporadic IBM. All patients underwent MRI of the bilateral upper and lower extremities. The images were scored for muscle atrophy, fatty infiltration, and edema pattern. Clinical data included onset and duration of disease. Muscle strength was measured using the Medical Research Council (MRC) scale, and functional status was assessed using the Modified Rankin Scale. Correlation between MRI and different clinical and functional parameters was calculated using the Spearman rank test and Pearson correlation. All patients showed MRI abnormalities, which were more severe within the lower limbs and the distal segments. The most prevalent MRI finding was fat infiltration. There was a statistically significant correlation between disease duration and number of muscles infiltrated by fat (r = 0.65; p = 0.04). The number of muscles with fat infiltration correlated with the sum of the scores of MRC (r = -0.60; p = 0.04) and with the Modified Rankin Scale (r = 0.48; p = 0.03). Our findings suggest that most patients with biopsy-proven sporadic IBM present with a typical pattern of muscle involvement at MRI, more extensively in the lower extremities. Moreover, MRI findings strongly correlated with clinical and functional parameters, because both the extent and severity of muscle involvement assessed by MRI and clinical and functional parameters are associated with the early onset of the disease and its duration.
Early Reconstructions of Complex Lower Extremity Battlefield Soft Tissue Wounds
Ebrahimi, Ali; Nejadsarvari, Nasrin; Ebrahimi, Azin; Rasouli, Hamid Reza
2017-01-01
BACKGROUND Severe lower extremity trauma as a devastating combat related injury is on the rise and this presents reconstructive surgeons with significant challenges to reach optimal cosmetic and functional outcomes. This study assessed early reconstructions of complex lower extremity battlefield soft tissue wounds. METHODS This was a prospective case series study of battled field injured patients which was done in the Department of Plastic Surgery, Baqiyatallah University of Medical Sciences hospitals, Tehran, Iran between 2013-2015. In this survey, 73 patients were operated for reconstruction of lower extremity soft tissue defects due to battlefield injuries RESULTS Seventy-three patients (65 men, 8 womens) ranging from 21-48 years old (mean: 35 years) were enrolled. Our study showed that early debridement and bone stabilization and later coverage of complex battlefields soft tissue wounds with suitable flaps and grafts of lower extremity were effective method for difficult wounds managements with less amputation and infections. CONCLUSION Serial debridement and bone stabilization before early soft tissue reconstruction according to reconstructive ladder were shown to be essential steps. PMID:29218283
On acquisition of programming knowledge
NASA Technical Reports Server (NTRS)
Amin, Ashok T.
1987-01-01
For the evolving discipline of programming, acquisition of programming knowledge is a difficult issue. Common knowledge results from the acceptance of proven techniques based on results of formal inquiries into the nature of the programming process. This is a rather slow process. In addition, the vast body of common knowledge needs to be explicated to a low enough level of details for it to be represented in the machine processable form. It is felt that this is an impediment to the progress of automatic programming. The importance of formal approaches cannot be overstated since their contributions lead to quantum leaps in the state of the art.
Gravity inversion of a fault by Particle swarm optimization (PSO).
Toushmalani, Reza
2013-01-01
Particle swarm optimization is a heuristic global optimization method and also an optimization algorithm, which is based on swarm intelligence. It comes from the research on the bird and fish flock movement behavior. In this paper we introduce and use this method in gravity inverse problem. We discuss the solution for the inverse problem of determining the shape of a fault whose gravity anomaly is known. Application of the proposed algorithm to this problem has proven its capability to deal with difficult optimization problems. The technique proved to work efficiently when tested to a number of models.
Effect of climate on the storage and turnover of carbon in soils
NASA Technical Reports Server (NTRS)
Trumbore, Susan; Chadwick, Oliver; Amundson, Ronald; Brasher, Benny
1994-01-01
Climate is, in many instances, the dominant variable controlling the storage of carbon in soils. It has proven difficult, however, to determine how soil properties influenced by climate, such as soil temperature and soil moisture, actually operate to determine the rates of accumulation and decomposition of soil organic matter. Our approach has been to apply a relatively new tool, the comparison of C-14 in soil organic matter from pre- and post-bomb soils, to quantify carbon turnover rates along climosequences. This report details the progress made toward this end by work under this contract.
Evolutionary computing for the design search and optimization of space vehicle power subsystems
NASA Technical Reports Server (NTRS)
Kordon, Mark; Klimeck, Gerhard; Hanks, David; Hua, Hook
2004-01-01
Evolutionary computing has proven to be a straightforward and robust approach for optimizing a wide range of difficult analysis and design problems. This paper discusses the application of these techniques to an existing space vehicle power subsystem resource and performance analysis simulation in a parallel processing environment. Out preliminary results demonstrate that this approach has the potential to improve the space system trade study process by allowing engineers to statistically weight subsystem goals of mass, cost and performance then automatically size power elements based on anticipated performance of the subsystem rather than on worst-case estimates.
How do yeast cells become tolerant to high ethanol concentrations?
Snoek, Tim; Verstrepen, Kevin J; Voordeckers, Karin
2016-08-01
The brewer's yeast Saccharomyces cerevisiae displays a much higher ethanol tolerance compared to most other organisms, and it is therefore commonly used for the industrial production of bioethanol and alcoholic beverages. However, the genetic determinants underlying this yeast's exceptional ethanol tolerance have proven difficult to elucidate. In this perspective, we discuss how different types of experiments have contributed to our understanding of the toxic effects of ethanol and the mechanisms and complex genetics underlying ethanol tolerance. In a second part, we summarize the different routes and challenges involved in obtaining superior industrial yeasts with improved ethanol tolerance.
NASA Astrophysics Data System (ADS)
Andersen, Peter S.; Stryhn, Anette; Hansen, Bjarke E.; Fugger, Lars; Engberg, Jan; Buus, Soren
1996-03-01
Specific recognition of peptide/major histocompatibility complex (MHC) molecule complexes by the T-cell receptor is a key reaction in the specific immune response. Antibodies against peptide/MHC complexes would therefore be valuable tools in studying MHC function and T-cell recognition and might lead to novel approaches in immunotherapy. However, it has proven difficult to generate antibodies with the specificity of T cells by conventional hybridoma techniques. Here we report that the phage display technology is a feasible alternative to generate antibodies recognizing specific, predetermined peptide/MHC complexes.
Scala Roles: Reusable Object Collaborations in a Library
NASA Astrophysics Data System (ADS)
Pradel, Michael; Odersky, Martin
Purely class-based implementations of object-oriented software are often inappropriate for reuse. In contrast, the notion of objects playing roles in a collaboration has been proven to be a valuable reuse abstraction. However, existing solutions to enable role-based programming tend to require vast extensions of the underlying programming language, and thus, are difficult to use in every day work. We present a programming technique, based on dynamic proxies, that allows to augment an object’s type at runtime while preserving strong static type safety. It enables role-based implementations that lead to more reuse and better separation of concerns.
Habibov, Nazim
2016-03-01
There is the lack of consensus about the effect of corruption on healthcare satisfaction in transitional countries. Interpreting the burgeoning literature on this topic has proven difficult due to reverse causality and omitted variable bias. In this study, the effect of corruption on healthcare satisfaction is investigated in a set of 12 Post-Socialist countries using instrumental variable regression on the sample of 2010 Life in Transition survey (N = 8655). The results indicate that experiencing corruption significantly reduces healthcare satisfaction. Copyright © 2016 The Author. Published by Elsevier Ltd.. All rights reserved.
Cystic Fibrosis Transmembrane Conductance Regulator (ABCC7) Structure
Hunt, John F.; Wang, Chi; Ford, Robert C.
2013-01-01
Structural studies of the cystic fibrosis transmembrane conductance regulator (CFTR) are reviewed. Like many membrane proteins, full-length CFTR has proven to be difficult to express and purify, hence much of the structural data available is for the more tractable, independently expressed soluble domains. Therefore, this chapter covers structural data for individual CFTR domains in addition to the sparser data available for the full-length protein. To set the context for these studies, we will start by reviewing structural information on model proteins from the ATP-binding cassette (ABC) transporter superfamily, to which CFTR belongs. PMID:23378596
Buckley, Lauren B; Huey, Raymond B
2016-12-01
Extreme temperatures can injure or kill organisms and can drive evolutionary patterns. Many indices of extremes have been proposed, but few attempts have been made to establish geographic patterns of extremes and to evaluate whether they align with geographic patterns in biological vulnerability and diversity. To examine these issues, we adopt the CLIMDEX indices of thermal extremes. We compute scores for each index on a geographic grid during a baseline period (1961-1990) and separately for the recent period (1991-2010). Heat extremes (temperatures above the 90th percentile during the baseline period) have become substantially more common during the recent period, particularly in the tropics. Importantly, the various indices show weak geographic concordance, implying that organisms in different regions will face different forms of thermal stress. The magnitude of recent shifts in indices is largely uncorrelated with baseline scores in those indices, suggesting that organisms are likely to face novel thermal stresses. Organismal tolerances correlate roughly with absolute metrics (mainly for cold), but poorly with metrics defined relative to local conditions. Regions with high extreme scores do not correlate closely with regions with high species diversity, human population density, or agricultural production. Even though frequency and intensity of extreme temperature events have - and are likely to have - major impacts on organisms, the impacts are likely to be geographically and taxonomically idiosyncratic and difficult to predict. © 2016 John Wiley & Sons Ltd.
Transition. Practice Perspectives--Highlighting Information on Deaf-Blindness. Number 4
ERIC Educational Resources Information Center
Malloy, Peggy; McGinnity, Betsy
2009-01-01
Finding a job, learning to live independently, and obtaining further education are important goals for all young adults as they leave high school. But achieving these goals is often extremely difficult for students who are deaf-blind. Limited or absent hearing and vision, difficulties with communication, and the frequent presence of additional…
An Extreme Case of Action Learning at BAT Niemeyer
ERIC Educational Resources Information Center
Eckstein, Emiel; Veenhoven, Gert; De Loo, Ivo
2009-01-01
Becoming a "winning organization" when one currently is an "ugly ducking" can be a difficult and strenuous task. BAT Niemeyer in the Netherlands succeeded in making such a transformation over the course of four years. Action learning was used, among other methods, to steer part of this transformation, in which employee…
Information and knowledge management in support of sustainable forestry: a review
H. Michael Rauscher; Daniel L. Schmoldt; Harald Vacik
2007-01-01
For individuals, organizations and nations, success and even survival depend upon making good decisions. Doing so can be extremely difficult when problems are not well structured and situations are complex, as they are for natural resource management. Recent advances in computer technology coupled with the increase in accessibility brought about by the...
Open Access, Retention and Throughput at the Central University of Technology
ERIC Educational Resources Information Center
de Beer, K. J.
2006-01-01
The most debatable question in higher education today is: Why first "open access" to promote massafication and now "capping" to restrict learner intake? (cf. SA Media Information 2004). Concerning the managing of this difficult and extremely sensitive issue, the Central University of Technology, Free State (CUT) has come a long…
Training Programs That Facilitate Lasting Change in Student Academic Behaviour
ERIC Educational Resources Information Center
Hodge, Brad
2014-01-01
A range of evidence suggests that changing a person's pattern of behaviour is extremely difficult, with past behaviour being one of the strongest predictors of future behaviour. This is particularly evident in the university setting where students tend to use the same academic processes they have used throughout their schooling despite any…
Personal Experiences of the Criminal Justice System by Individuals with Autism Spectrum Disorders
ERIC Educational Resources Information Center
Helverschou, Sissel Berge; Steindal, Kari; Nøttestad, Jim Aage; Howlin, Patricia
2018-01-01
The processes of arrest, investigation, trial and imprisonment are often extremely difficult for individuals with autism spectrum disorders. In this study, nine offenders with autism spectrum disorders were interviewed about the circumstance surrounding the criminal acts, their views of the arrest, the police interrogation, the trial and the…
Mining Formative Evaluation Rules Using Web-Based Learning Portfolios for Web-Based Learning Systems
ERIC Educational Resources Information Center
Chen, Chih-Ming; Hong, Chin-Ming; Chen, Shyuan-Yi; Liu, Chao-Yu
2006-01-01
Learning performance assessment aims to evaluate what knowledge learners have acquired from teaching activities. Objective technical measures of learning performance are difficult to develop, but are extremely important for both teachers and learners. Learning performance assessment using learning portfolios or web server log data is becoming an…
How Can "Problem Subjects" Be Made Less of a Problem?
ERIC Educational Resources Information Center
Warwick, Philip; Ottewill, Roger
2004-01-01
Many higher education courses, across the whole range of disciplines, include subjects that are somewhat problematic because they appear to be unrelated to other components of the curriculum. Students frequently perceive them as irrelevant and boring. This makes it extremely difficult for lecturers to stimulate interest and results in an…
The Coach-Team Approach: An Introductory Accounting Instructional Alternative
ERIC Educational Resources Information Center
Wood, Lynette I.
2012-01-01
Many students approach the introductory accounting course with a great deal of apprehension. For the most part, the course is populated by non-accounting majors who often perceive accounting to be extremely difficult and may view the instructor-student relationship as adversarial. As a result, such students may be inclined to express their…
ERIC Educational Resources Information Center
Price, Kelly; Price, Julia
2016-01-01
When digitally marketing an online educational program, degree or course, an institution must realize the target market which it is trying to reach. However, the demographics of the online student is extremely diverse, making marketing efforts difficult. With such a demographically diverse online student population to attract, it is important to…
Free metal ions are usually the most bioavailable and toxic metal species to aquatic organisms, but they are difficult to measure because of their extremely low concentrations in the marine environment. Many of the current methods for determining free metal ions are complicated a...
Fire behavior sensor package remote trigger design
Dan Jimenez; Jason Forthofer; James Reardon; Bret Butler
2007-01-01
Fire behavior characteristics (such as temperature, radiant and total heat flux, 2- and 3-dimensional velocities, and air flow) are extremely difficult to measure insitu. Although insitu sensor packages are capable of such measurements in realtime, it is also essential to acquire video documentation as a means of better understanding the fire behavior data recorded by...
Teaching and Learning: Hokie Spirit
ERIC Educational Resources Information Center
Lindeman, Cheryl A.
2007-01-01
If teachers were to reflect about their most difficult teachable moments in their careers, the author is sure the Virginia Tech tragedy would be extremely taxing on their minds. For those teachers teaching high school seniors, who were in the process of sending deposits to Virginia Tech, it was particularly agonizing. In this article, the author…
Guo, LanJun; Li, Yan; Han, Ruquan; Gelb, Adrian W
2018-01-01
Motor evoked potentials (MEPs) are commonly used during surgery for spinal cord tumor resection. However, it can be difficult to record reliable MEPs from the muscles of the lower extremities during surgery in patients with preoperative weakness due to spinal cord compression. In this study, motor function of patients' lower extremities and their association with intraoperative MEP recording were compared. Patients undergoing thoracic spinal cord tumor resection were studied. Patients' motor function was checked immediately before the surgical procedure. MEP responses were recorded from the tibialis anterior and foot muscles, and the hand muscles were used as control. Electrical current with train of eight pulses, 200 to 500 V was delivered through 2 corkscrews placed at C3' and C4' sites. Anesthesia was maintained by total intravenous anesthesia using a combination of propofol and remifentanil after induction with intravenous propofol, remifentanil, and rocuronium. Rocuronium was not repeated. Bispectral Index was maintained between 40 to 50. From 178 lower limbs of 89 patients, myogenic MEPs could be recorded from 100% (105/105) of the patients with 5 of 5 motor strength in lower extremity; 90% (36/40) from the patients with 4/5 motor strength; only 25% (5/20) with 3/5; and 12.5% (1/8) with 2/5 motor strength; none (0/5) were able to be recorded if the motor strength was 1/5. The ability to record myogenic MEPs is closely associated with the patient's motor function. They are difficult to obtain if motor function is 3/5 motor strength in the lower extremity. They are almost impossible to record if motor function is worse than 3/5.
Low Bandwidth Robust Controllers for Flight
NASA Technical Reports Server (NTRS)
Biezad, Daniel J.; Chou, Hwei-Lan
1993-01-01
Through throttle manipulations, engine thrust can be used for emergency flight control for multi-engine aircraft. Previous study by NASA Dryden has shown the use of throttles for emergency flight control to be very difficult. In general, manual fly-by-throttle is extremely difficult - with landing almost impossible, but control augmentation makes runway landings feasible. Flight path control using throttles-only to achieve safe emergency landing for a large jet transport airplane, Boeing 720, was investigated using Quantitative Feedback Theory (QFT). Results were compared to an augmented control developed in a previous simulation study. The control augmentation corrected the unsatisfactory open-loop characteristics by increasing system bandwidth and damping, but increasing the control bandwidth substantially proved very difficult. The augmented pitch control is robust under no or moderate turbulence. The augmented roll control is sensitive to configuration changes.
Low bandwidth robust controllers for flight
NASA Technical Reports Server (NTRS)
Biezad, Daniel J.; Chou, Hwei-Lan
1993-01-01
Through throttle manipulations, engine thrust can be used for emergency flight control for multi-engine aircraft. Previous study by NASA Dryden has shown the use of throttles for emergency flight control to be very difficult. In general, manual fly-by-throttle is extremely difficult - with landing almost impossible, but control augmentation makes runway landings feasible. Flight path control using throttles-only to achieve safe emergency landing for a large jet transport airplane, Boeing 720, was investigated using Quantitative Feedback Theory (QFT). Results were compared to an augmented control developed in a previous simulation study. The control augmentation corrected the unsatisfactory open-loop characteristics by increasing system bandwidth and damping, but increasing the control bandwidth substantially proved very difficult. The augmented pitch control is robust under no or moderate turbulence. The augmented roll control is sensitive to configuration changes.
The enhancement of friction ridge detail on brass ammunition casings using cold patination fluid.
James, Richard Michael; Altamimi, Mohamad Jamal
2015-12-01
Brass ammunition is commonly found at firearms related crime scenes. For this reason, many studies have focused on evidence that can be obtained from brass ammunition such as DNA, gunshot residue and fingerprints. Latent fingerprints on ammunition can provide good forensic evidence, however; fingerprint development on ammunition casings has proven to be difficult. A method using cold patination fluid is described as a potential tool to enhance friction ridge detail on brass ammunition casings. Current latent fingerprint development methods for brass ammunition have either failed to provide the necessary quality of friction ridge detail or can be very time consuming and require expensive equipment. In this study, the enhancement of fingerprints on live ammunition has been achieved with a good level of detail whilst the development on spent casings has to an extent also been possible. Development with cold patination fluid has proven to be a quick, simple and cost-effective method for fingerprint development on brass ammunition that can be easily implemented for routine police work. Crown Copyright © 2015. Published by Elsevier Ireland Ltd. All rights reserved.
Mina, Eleni; Thompson, Mark; Kaliyaperumal, Rajaram; Zhao, Jun; der Horst, van Eelke; Tatum, Zuotian; Hettne, Kristina M; Schultes, Erik A; Mons, Barend; Roos, Marco
2015-01-01
Data from high throughput experiments often produce far more results than can ever appear in the main text or tables of a single research article. In these cases, the majority of new associations are often archived either as supplemental information in an arbitrary format or in publisher-independent databases that can be difficult to find. These data are not only lost from scientific discourse, but are also elusive to automated search, retrieval and processing. Here, we use the nanopublication model to make scientific assertions that were concluded from a workflow analysis of Huntington's Disease data machine-readable, interoperable, and citable. We followed the nanopublication guidelines to semantically model our assertions as well as their provenance metadata and authorship. We demonstrate interoperability by linking nanopublication provenance to the Research Object model. These results indicate that nanopublications can provide an incentive for researchers to expose data that is interoperable and machine-readable for future use and preservation for which they can get credits for their effort. Nanopublications can have a leading role into hypotheses generation offering opportunities to produce large-scale data integration.
Dynamic Non-Hierarchical File Systems for Exascale Storage
DOE Office of Scientific and Technical Information (OSTI.GOV)
Long, Darrell E.; Miller, Ethan L
This constitutes the final report for “Dynamic Non-Hierarchical File Systems for Exascale Storage”. The ultimate goal of this project was to improve data management in scientific computing and high-end computing (HEC) applications, and to achieve this goal we proposed: to develop the first, HEC-targeted, file system featuring rich metadata and provenance collection, extreme scalability, and future storage hardware integration as core design goals, and to evaluate and develop a flexible non-hierarchical file system interface suitable for providing more powerful and intuitive data management interfaces to HEC and scientific computing users. Data management is swiftly becoming a serious problem in themore » scientific community – while copious amounts of data are good for obtaining results, finding the right data is often daunting and sometimes impossible. Scientists participating in a Department of Energy workshop noted that most of their time was spent “...finding, processing, organizing, and moving data and it’s going to get much worse”. Scientists should not be forced to become data mining experts in order to retrieve the data they want, nor should they be expected to remember the naming convention they used several years ago for a set of experiments they now wish to revisit. Ideally, locating the data you need would be as easy as browsing the web. Unfortunately, existing data management approaches are usually based on hierarchical naming, a 40 year-old technology designed to manage thousands of files, not exabytes of data. Today’s systems do not take advantage of the rich array of metadata that current high-end computing (HEC) file systems can gather, including content-based metadata and provenance1 information. As a result, current metadata search approaches are typically ad hoc and often work by providing a parallel management system to the “main” file system, as is done in Linux (the locate utility), personal computers, and enterprise search appliances. These search applications are often optimized for a single file system, making it difficult to move files and their metadata between file systems. Users have tried to solve this problem in several ways, including the use of separate databases to index file properties, the encoding of file properties into file names, and separately gathering and managing provenance data, but none of these approaches has worked well, either due to limited usefulness or scalability, or both. Our research addressed several key issues: High-performance, real-time metadata harvesting: extracting important attributes from files dynamically and immediately updating indexes used to improve search; Transparent, automatic, and secure provenance capture: recording the data inputs and processing steps used in the production of each file in the system; Scalable indexing: indexes that are optimized for integration with the file system; Dynamic file system structure: our approach provides dynamic directories similar to those in semantic file systems, but these are the native organization rather than a feature grafted onto a conventional system. In addition to these goals, our research effort will include evaluating the impact of new storage technologies on the file system design and performance. In particular, the indexing and metadata harvesting functions can potentially benefit from the performance improvements promised by new storage class memories.« less
Computational discovery of extremal microstructure families
Chen, Desai; Skouras, Mélina; Zhu, Bo; Matusik, Wojciech
2018-01-01
Modern fabrication techniques, such as additive manufacturing, can be used to create materials with complex custom internal structures. These engineered materials exhibit a much broader range of bulk properties than their base materials and are typically referred to as metamaterials or microstructures. Although metamaterials with extraordinary properties have many applications, designing them is very difficult and is generally done by hand. We propose a computational approach to discover families of microstructures with extremal macroscale properties automatically. Using efficient simulation and sampling techniques, we compute the space of mechanical properties covered by physically realizable microstructures. Our system then clusters microstructures with common topologies into families. Parameterized templates are eventually extracted from families to generate new microstructure designs. We demonstrate these capabilities on the computational design of mechanical metamaterials and present five auxetic microstructure families with extremal elastic material properties. Our study opens the way for the completely automated discovery of extremal microstructures across multiple domains of physics, including applications reliant on thermal, electrical, and magnetic properties. PMID:29376124
Diagnosis, treatment, and rehabilitation of stress fractures in the lower extremity in runners
Kahanov, Leamor; Eberman, Lindsey E; Games, Kenneth E; Wasik, Mitch
2015-01-01
Stress fractures account for between 1% and 20% of athletic injuries, with 80% of stress fractures in the lower extremity. Stress fractures of the lower extremity are common injuries among individuals who participate in endurance, high load-bearing activities such as running, military and aerobic exercise and therefore require practitioner expertise in diagnosis and management. Accurate diagnosis for stress fractures is dependent on the anatomical area. Anatomical regions such as the pelvis, sacrum, and metatarsals offer challenges due to difficulty differentiating pathologies with common symptoms. Special tests and treatment regimes, however, are similar among most stress fractures with resolution between 4 weeks to a year. The most difficult aspect of stress fracture treatment entails mitigating internal and external risk factors. Practitioners should address ongoing risk factors to minimize recurrence. PMID:25848327
Dynamic behavior of particles in spacecraft
NASA Technical Reports Server (NTRS)
Perrine, B. S.
1981-01-01
The behavior of particles relative to a spacecraft frame of reference was examined. Significant spatial excursions of particles in space can occur relative to the spacecraft frame of reference as a result of drag deceleration of the vehicle. These vehicle excursions tend to be large as time increases. Thus, if the particle is required to remain in a specified volume, constraints may be required. Thus, for example, in levitation experiments it may be extremely difficult to turn off the forces of constraint which keep the particles in a specified region. This means experiments which are sensitive to disturbances may be very difficult to perform if perturbation forces are required to be absent.
Yuan, Shi-Min
2016-01-01
Fungal endocarditis is a rare and fatal condition. The Candida and Aspergillus species are the two most common etiologic fungi found responsible for fungal endocarditis. Fever and changing heart murmur are the most common clinical manifestations. Some patients may have a fever of unknown origin as the onset symptom. The diagnosis of fungal endocarditis is challenging, and diagnosis of prosthetic valve fungal endocarditis is extremely difficult. The optimum antifungal therapy still remains debatable. Treating Candida endocarditis can be difficult because the Candida species can form biofilms on native and prosthetic heart valves. Combined treatment appears superior to monotherapy. Combination of antifungal therapy and surgical debridement might bring about better prognosis. PMID:27737409
Yuan, Shi-Min
2016-01-01
Fungal endocarditis is a rare and fatal condition. The Candida and Aspergillus species are the two most common etiologic fungi found responsible for fungal endocarditis. Fever and changing heart murmur are the most common clinical manifestations. Some patients may have a fever of unknown origin as the onset symptom. The diagnosis of fungal endocarditis is challenging, and diagnosis of prosthetic valve fungal endocarditis is extremely difficult. The optimum antifungal therapy still remains debatable. Treating Candida endocarditis can be difficult because the Candida species can form biofilms on native and prosthetic heart valves. Combined treatment appears superior to monotherapy. Combination of antifungal therapy and surgical debridement might bring about better prognosis.
Pathway models could aid management of contaminants
Luoma, S. N.
1995-01-01
Heavy metal and trace organic contaminants are often cited as factors that could affect the riclmess of the biological communi~ of San Francisco Bay as well as the health of resident organisms. Silver (Ag), selenium (Se), mercury (Hg), copper (Cu), nickel (Ni), chromium (Cr), and cadmium (Cd) are among the trace elements of current regulatory interest. All these elements can be toxic to estuarine organisms in minute quantities. However, understanding their toxicity in nature has proven a difficult challenge. In general, it is difficult to prove how pollutants are affecting ecosystems. The undisturbed "baseline" condition in San Francisco Bay is not always well enough understood to identify whether certain processes are affected or unaffected by contamination. Sources of disturbance (flow diversions, drought, invasion of exotic species, etc.) occur in addition to chemical contamination. Responses to contamination in individual organisms, populations, and commumties are seldom pollutant-specific, and the complex responses to moderate levels of contamination are not well known.
The Mulcahy Salvage: Past and Present Innovations.
Mellon, Matthew J; Broghammer, Joshua R; Henry, Gerard D
2015-11-01
Inflatable penile implants are a mainstay for the surgical correction of erectile dysfunction. For the last 40 years they have provided reliable outcomes with durable patient satisfaction. Infection of the implant continues to remain the primary surgical concern, despite the advent of antibiotic-coated devices and improved skin preparation solutions. In this article, we review and evaluate the published literature for important contributions surrounding the various salvage techniques and washout strategies. In addition, the role of biofilm in prosthetic infection will be discussed. First described by Mulcahy for instances of device infection, the salvage or rescue procedure was established to avoid complete removal and staged replacement. This approach, with its avoidance of difficult revision surgery, penile shortening and patient discomfort, has produced success as high as 84%. Mulcahy's innovative approach at salvage or rescue reimplantation has proven to be a highly successful approach to this difficult surgical problem. Without question, the report of the long-term results of his salvage patients has directly influenced a generation of prosthetic surgeons. © 2015 International Society for Sexual Medicine.
A low-cost solid–liquid separation process for enzymatically hydrolyzed corn stover slurries
Sievers, David A.; Lischeske, James J.; Biddy, Mary J.; ...
2015-07-01
Solid-liquid separation of intermediate process slurries is required in some process configurations for the conversion of lignocellulosic biomass to transportation fuels. Thermochemically pretreated and enzymatically hydrolyzed corn stover slurries have proven difficult to filter due to formation of very low permeability cakes that are rich in lignin. Treatment of two different slurries with polyelectrolyte flocculant was demonstrated to increase mean particle size and filterability. Filtration flux was greatly improved, and thus scaled filter unit capacity was increased approximately 40-fold compared with unflocculated slurry. Although additional costs were accrued using polyelectrolyte, techno-economic analysis revealed that the increase in filter capacity significantlymore » reduced overall production costs. Fuel production cost at 95% sugar recovery was reduced by $1.35 US per gallon gasoline equivalent for dilute-acid pretreated and enzymatically hydrolyzed slurries and $3.40 for slurries produced using an additional alkaline de-acetylation preprocessing step that is even more difficult to natively filter.« less
The Hottest Hot Jupiters May Host Atmospheric Dynamos
DOE Office of Scientific and Technical Information (OSTI.GOV)
Rogers, T. M.; McElwaine, J. N.
2017-06-01
Hot Jupiters have proven themselves to be a rich class of exoplanets that test our theories of planetary evolution and atmospheric dynamics under extreme conditions. Here, we present three-dimensional magnetohydrodynamic simulations and analytic results that demonstrate that a dynamo can be maintained in the thin, stably stratified atmosphere of a hot Jupiter, independent of the presumed deep-seated dynamo. This dynamo is maintained by conductivity variations arising from strong asymmetric heating from the planets’ host star. The presence of a dynamo significantly increases the surface magnetic field strength and alters the overall planetary magnetic field geometry, possibly affecting star–planet magnetic interactions.
Compact high reliability fiber coupled laser diodes for avionics and related applications
NASA Astrophysics Data System (ADS)
Daniel, David R.; Richards, Gordon S.; Janssen, Adrian P.; Turley, Stephen E. H.; Stockton, Thomas E.
1993-04-01
This paper describes a newly developed compact high reliability fiber coupled laser diode which is capable of providing enhanced performance under extreme environmental conditions including a very wide operating temperature range. Careful choice of package materials to minimize thermal and mechanical stress, used with proven manufacturing methods, has resulted in highly stable coupling of the optical fiber pigtail to a high performance MOCVD-grown Multi-Quantum Well laser chip. Electro-optical characteristics over temperature are described together with a demonstration of device stability over a range of environmental conditions. Real time device lifetime data is also presented.
Agureev, A N; Kalandarov, S; Bogatova, R I; Krivitsina, Z A; Vasil'eva, V F
2005-01-01
Food rations composed of canned products were given the physiological and hygienic evaluation in the context of their fitness for human volunteers in experiments with head-down bedrest in isolation and confinement. As a result, the food rations were proven to contain the desired quantities of nutrients. Evaluation of food fitness for human subjects was made based on the data of clinical-physiological and biochemical investigations. The rations met the energy and anabolic metabolism demands of human subjects during extreme chamber experiments and were favorable to maintaining good level of vital processes.
NASA Astrophysics Data System (ADS)
Krause, O.; Bouchiat, V.; Bonnot, A. M.
2007-03-01
Due to their extreme aspect ratios and exceptional mechanical properties Carbon Nanotubes terminated silicon probes have proven to be the ''ideal'' probe for Atomic Force Microscopy. But especially for the manufacturing and use of Single Walled Carbon Nanotubes there are serious problems, which have not been solved until today. Here, Single and Double Wall Carbon Nanotubes, batch processed and used as deposited by Chemical Vapor Deposition without any postprocessing, are compared to standard and high resolution silicon probes concerning resolution, scanning speed and lifetime behavior.
Hardening communication ports for survival in electrical overstress environments
NASA Technical Reports Server (NTRS)
Clark, O. Melville
1991-01-01
Greater attention is being focused on the protection of data I/O ports since both experience and lab tests have shown that components at these locations are extremely vulnerable to electrical overstress (EOS) in the form of transient voltages. Lightning and electrostatic discharge (ESD) are the major contributors to these failures; however, these losses can be prevented. Hardening against transient voltages at both the board level and system level has a proven record of improving reliability by orders of magnitude. The EOS threats, typical failure modes, and transient voltage mitigation techniques are reviewed. Case histories are also reviewed.
Versatile microbial surface-display for environmental remediation and biofuels production
DOE Office of Scientific and Technical Information (OSTI.GOV)
Wu, Cindy H.; Mulchandani, Ashok; Chen, wilfred
2008-02-14
Surface display is a powerful technique that utilizes natural microbial functional components to express proteins or peptides on the cell exterior. Since the reporting of the first surface-display system in the mid-1980s, a variety of new systems have been reported for yeast, Gram-positive and Gram-negative bacteria. Non-conventional display methods are emerging, eliminating the generation of genetically modified microorganisms. Cells with surface display are used as biocatalysts, biosorbents and biostimulants. Microbial cell-surface display has proven to be extremely important for numerous applications ranging from combinatorial library screening and protein engineering to bioremediation and biofuels production.
Nature, Nurture and Epigenetics
Crews, David; Gillette, Ross; Miller-Crews, Isaac; Gore, Andrea C.; Skinner, Michael K.
2015-01-01
Real life by definition combines heritability (e.g., the legacy of exposures) and experience (e.g. stress during sensitive or ‘critical’ periods), but how to study or even model this interaction has proven difficult. The hoary concept of evaluating traits according to nature vs. nurture continues to persist despite repeated demonstrations that it retards, rather than advances, our understanding of biological processes. Behavioral genetics has proven the obvious, that genes influences behavior and, vice versa, that behavior influences genes. The concept of Genes X Environment (G X E) and its modern variants was viewed as an improvement on nature-nurture but has proven that, except in rare instances, it is not possible to fractionate phenotypes into these constituent elements. The entanglement inherent in terms such as nature-nurture or GXE is a Gordian knot that cannot be dissected or even split. Given that the world today is not what it was less than a century ago, yet the arbitrator (differential survival and reproduction) has stayed constant, de novo principles and practices are needed to better predict what the future holds. Put simply, the transformation that is now occurring within and between individuals as a product of global endocrine disruption is quite independent of what has been regarded as evolution by selection. This new perspective should focus on how epigenetic modifications might revise approaches to understand how the phenotype and, in particular its components, is shaped. In this review we summarize the literature in this developing area, focusing on our research on the fungicide vinclozolin. PMID:25102229
NASA Astrophysics Data System (ADS)
Gammon, P. R.; Savard, M. M.; Ahad, J. M.; Girard, I.
2016-12-01
The Athabasca Oil Sands (AOS) industry in Alberta, Canada deposits voluminous waste streams in Earth's largest tailings ponds (TPs). Detecting and tracing contaminant discharge from TPs to subsurface aquifers has proven difficult because tailings have the same composition as the surrounding environment of unmined oil sand. To trace pond discharge to the subsurface therefore relies on the waste stream hosting additions or alterations induced by mining or industrial processes. Inorganic element or contaminant concentration data have proven ineffective at tracing because there is insufficient alteration of the chemical constituents or their ratios. Metal isotopes have not generally been applied to tracing emissions even though isotopic fractionation is likely induced via the high temperature and pH industrial process. We have generated Mg, Li, Pb and Zn isotopic data for a range of groundwater wells and TPs. Mg isotopes are excellent for distinguishing deep saline brines that are pumped into the waste stream during mine dewatering. Li isotopes appear to be heavily fractionated during processing, which produces a heavy isotopic signature that is an excellent tracer of production water. Pb isotopes discriminate Pb derived from oil-sand versus bedrock carbonate. Juxtapositions of TPs, carbonates and near-surface aquifers are common and of significant regulatory concern, making Pb isotopes particularly useful. Zn isotopic data indicates similarities to Pb isotopes, but are difficult to obtain due to low concentrations. Combining the isotopic data with concentration data and hydrologic models will assist in determining the fluxes of discharges from the TPs to near-surface aquifers. The range of environmental contexts of AOS TPs is limited and thus monitoring discharges to nearby aquifers from TPs could feasibly be accomplished using tailored suites of metal isotopes.
Doping of wide-bandgap titanium-dioxide nanotubes: optical, electronic and magnetic properties
NASA Astrophysics Data System (ADS)
Alivov, Yahya; Singh, Vivek; Ding, Yuchen; Cerkovnik, Logan Jerome; Nagpal, Prashant
2014-08-01
Doping semiconductors is an important step for their technological application. While doping bulk semiconductors can be easily achieved, incorporating dopants in semiconductor nanostructures has proven difficult. Here, we report a facile synthesis method for doping titanium-dioxide (TiO2) nanotubes that was enabled by a new electrochemical cell design. A variety of optical, electronic and magnetic dopants were incorporated into the hollow nanotubes, and from detailed studies it is shown that the doping level can be easily tuned from low to heavily-doped semiconductors. Using desired dopants - electronic (p- or n-doped), optical (ultraviolet bandgap to infrared absorption in co-doped nanotubes), and magnetic (from paramagnetic to ferromagnetic) properties can be tailored, and these technologically important nanotubes can be useful for a variety of applications in photovoltaics, display technologies, photocatalysis, and spintronic applications.Doping semiconductors is an important step for their technological application. While doping bulk semiconductors can be easily achieved, incorporating dopants in semiconductor nanostructures has proven difficult. Here, we report a facile synthesis method for doping titanium-dioxide (TiO2) nanotubes that was enabled by a new electrochemical cell design. A variety of optical, electronic and magnetic dopants were incorporated into the hollow nanotubes, and from detailed studies it is shown that the doping level can be easily tuned from low to heavily-doped semiconductors. Using desired dopants - electronic (p- or n-doped), optical (ultraviolet bandgap to infrared absorption in co-doped nanotubes), and magnetic (from paramagnetic to ferromagnetic) properties can be tailored, and these technologically important nanotubes can be useful for a variety of applications in photovoltaics, display technologies, photocatalysis, and spintronic applications. Electronic supplementary information (ESI) available: See DOI: 10.1039/c4nr02417f
Numerical simulation of crystal fractionation in shergottite meteorites
NASA Astrophysics Data System (ADS)
Grimm, R. E.; McSween, H. Y., Jr.
Cumulus clinopyroxenes in the Shergotty and Zagami meteorites suggest crystal fractionation occurred, possibly by gravitative settling. Numerical models of this process in a nonconvecting environment argue that the small phenocrysts can segregate only under extreme conditions of cooling time or gravitational field strength. Since textures indicate that cooling time was not excessive, a large (planetary) g is required by these models, in agreement with other suggestions that the shergottite parent body may be Mars. Other calculations indicate that it is extremely difficult to produce the observed textures in a convecting environment, unless crystal setting occurred in a quiescent zone at the bottom of the magma chamber.
Numerical simulation of crystal fractionation in shergottite meteorites
NASA Technical Reports Server (NTRS)
Grimm, R. E.; Mcsween, H. Y., Jr.
1982-01-01
Cumulus clinopyroxenes in the Shergotty and Zagami meteorites suggest crystal fractionation occurred, possibly by gravitative settling. Numerical models of this process in a nonconvecting environment argue that the small phenocrysts can segregate only under extreme conditions of cooling time or gravitational field strength. Since textures indicate that cooling time was not excessive, a large (planetary) g is required by these models, in agreement with other suggestions that the shergottite parent body may be Mars. Other calculations indicate that it is extremely difficult to produce the observed textures in a convecting environment, unless crystal setting occurred in a quiescent zone at the bottom of the magma chamber.
The Major Solar Eruptive Event in July 2012: Defining Extreme Space Weather Scenarios (Invited)
NASA Astrophysics Data System (ADS)
Baker, D. N.
2013-12-01
A key goal for the space weather community is to define extreme conditions that might plausibly afflict human technology. On 23 July 2012 solar active region 1520 (~133°W heliographic longitude) gave rise to a powerful coronal mass ejection (CME) with an initial speed that was determined to be >3000 km/s. The eruption was directed away from Earth toward 144°W longitude. STEREO-A sensors detected the CME arrival only about 18 hours later and made in situ measurements of the solar wind and interplanetary magnetic field. We have posed the question of what would have happened if this huge interplanetary event had been Earthward directed. Using a well-proven geomagnetic storm forecast model, we find that the 23-24 July event would certainly have produced a geomagnetic storm that was comparable to the largest events of the 20th Century (Dst ~ -500nT). Using plausible assumptions about seasonal and time-of-day orientation of the Earth's magnetic dipole, the most extreme modeled value of storm-time disturbance would have been Dst=-1182nT. This is probably considerably larger than the famous Carrington storm of 1859. This finding has far reaching implications because it demonstrates that extreme space weather conditions such as those during March of 1989 or September of 1859 can happen even during a modest solar activity cycle such as the one presently underway. We argue that this extreme event should immediately be employed by the space weather community to model severe space weather effects on technological systems such as the electric power grid.
Managing Conflict with Direct Reports. For the Practicing Manager. An Ideas into Action Guidebook.
ERIC Educational Resources Information Center
Popejoy, Barbara; McManigle, Brenda J.
Conflict is inevitable when people work together because they have different points of view, values, and ways of working. Resolving conflicts can be extremely difficult because of these differences. This short guidebook addresses ways successful leaders can work to manage conflict in the workplace, in particular conflict with people who report to…
Alaska biological control program directed at amber-marked birch leaf miner.
J.E. Lundquist; K.F. Zogas; C.L. Snyder; B.K. Schulz
2008-01-01
Nonnative invasive insects are having major impacts on the economics and ecology of forests nationwide. Until recently, Alaska was fortunately mostly free of these pests. Because of the remoteness of much of Alaska's native forests, an invasive pest infestation would be extremely difficult to control. Global markets, global climate change, and the ever-increasing...
What Recourse for the Principal Abused by Community Activists? The Case of "Stevens v. Tillman."
ERIC Educational Resources Information Center
Menacker, Julius
1990-01-01
"Stevens v. Tillman" illustrates the limited reach of federal law in controversies where community activists use extreme, even illegal, methods to exert their will over objecting school officials. Defamation charges against activists for verbal abuses will apparently be very difficult to sustain, given court views that being called a…
USDA-ARS?s Scientific Manuscript database
Cynodon dactylon (L.) Pers. (common bermudagrass) is a troublesome perennial grass common in the southeastern U. S. and extremely difficult to control in organic crop production systems. Research trials in a site heavily infested with C. dactylon were conducted from 2008 to 2010 to evaluate systems...
Adaptive Techniques for Control of Large Space Structures.
1984-12-01
uncertainty, diverge and ultimately go unstable. This problem is extremely difficult and has only recently been addressed, even in the general context of...L. (4.7b) Corollary 1: Performance Bounds Suppose z. and e. satisfy the conditions in () of Theroems 1A or 18. I) Let H c SPR , i.e., - M, y > 0 such
The Impact of Social Software in Product Design Higher Education
ERIC Educational Resources Information Center
Hurn, Karl
2012-01-01
It is difficult to ignore the impact that Web 2.0 and the subsequent social software revolution has had on society in general, and young people in particular. Information is exchanged and interpreted extremely quickly and in ways that were not imagined 10 years ago. Universities are struggling to keep up with this new technology, with outdated…
A Simple Microscopy Assay to Teach the Processes of Phagocytosis and Exocytosis
ERIC Educational Resources Information Center
Gray, Ross; Gray, Andrew; Fite, Jessica L.; Jordan, Renee; Stark, Sarah; Naylor, Kari
2012-01-01
Phagocytosis and exocytosis are two cellular processes involving membrane dynamics. While it is easy to understand the purpose of these processes, it can be extremely difficult for students to comprehend the actual mechanisms. As membrane dynamics play a significant role in many cellular processes ranging from cell signaling to cell division to…
ERIC Educational Resources Information Center
Lavi, Iris; Slone, Michelle
2011-01-01
Children in countries involved in violent national conflicts experience difficult and, at times, extreme events such as spending long hours in shelters, witnessing terror attacks, or having a family member absent or injured while participating in battle. This study explores the moderating effect of resilience factors, self-esteem, and…
Visual impacts in the urban-wildland interface
Arthur W. Magill; Rowan A. Rowntree; Robert O. Brush
1979-01-01
The urban-wildland interface is treated as a place where extremes meet--where it is difficult to maintain a visually appealing transition from country to city. Problems are identified in relation to stable cities, urbanizing areas, and developing resorts in the wildlands. The visual problems of urbanization are also discussed in relation to physical impacts such as...
ERIC Educational Resources Information Center
Young, Nancy L.; Barden, Wendy S.; Mills, Wendy A.; Burke, Tricia A.; Law, Mary; Boydell, Katherine
2009-01-01
Introduction: The transition to adulthood is extremely difficult for individuals with disabilities. We sought to explore the specific issue of transition to adult-oriented health care in a Canadian context. Methods: We conducted semi-structured individual interviews with 15 youth and 15 adults with cerebral palsy, spina bifida, and acquired brain…
New technology in postfire rehab
Joe Sabel
2007-01-01
PAM-12⢠is a recycled office paper byproduct made into a spreadable mulch with added Water Soluble Polyacrylamide (WSPAM), a previously difficult polymer to apply. PAM-12 is extremely versatile and can be applied through several methods. In a field test, PAM-12 outperformed straw in every targeted performance area: erosion control, improving soil hydrophobicity, and...
2014-06-13
corruption and cheating. This also makes it extremely difficult to determine the actual impact on the resource and the entire ecosystem . “Overfishing...limits, established under international agreements. By adversely impacting fisheries, marine ecosystems , food security and coastal communities around...
ERIC Educational Resources Information Center
Smith, Mike U.
Both teachers and students alike acknowledge that genetics and genetics problem-solving are extremely difficult to learn and to teach. Therefore, a number of recommendations for teaching college genetics are offered. Although few of these ideas have as yet been tested in controlled experiments, they are supported by research and experience and may…
Libraries in Today's Digital Age: The Copyright Controversy. ERIC Digest.
ERIC Educational Resources Information Center
Russell, Carrie
This digest focuses on the continuing ambiguities libraries and their users face in dealing with copyright in the digital environment. In the networked digital world, the basic principles of copyright are more difficult to apply. Digital copies are easy to create, modify, and manipulate, they are extremely easy to distribute widely over networks,…
Denying Social Harm: Students' Resistance to Lessons about Inequality
ERIC Educational Resources Information Center
Kleinman, Sherryl; Copp, Martha
2009-01-01
Students share folk beliefs that make it difficult for them to understand inequality, especially the harmful consequences of social practices they routinely engage in, are attached to, and take for granted. Four of these beliefs include: (a) harm is direct, extreme, and the product of an individual's intentions; (2) harm is the product of the…
Heterotopic Prostate at Autopsy- An Unusual Mass at the Dome of the Urinary Bladder.
Munde, Shital; Fernandes, Gwendolyn; Phadnis, Priyanka
2017-09-01
Heterotopic prostate in the dome of the urinary bladder is extremely rare and difficult to diagnose. It is often mistaken for neoplastic masses and histopathological examination is warranted for diagnosis. We report an autopsy case of an ectopic prostate at the dome of the bladder which mimicked a neoplasm on gross pathology.
Teaching about the Holocaust--A Resource Guide
ERIC Educational Resources Information Center
Russell, William Benedict, III
2005-01-01
Teaching about the Holocaust is an emotional process that can be extremely difficult, especially without the proper resources. Most teachers spend one or two class periods on the Holocaust and usually cram the lesson into a unit on World War II. As a teacher, the author understands that time is short and that it is impossible to spend the…
Hardwood cover crops:can they enhance loblolly pine seedling production
Paul P. Kormanik; Shi-Jean S. Sung; T.L. Kormanik; Stanley J. Zarnoch
1995-01-01
It has been extremely difficult to obtain more than two loblolly pine (Pinus taeda L.) crops following even effective soil fumigation with methyl bromide in southern forest tree nurseries. The traditional agronomic cover crops such as sorghum and sudex, unless followed by fumigation, do not normally produce satisfactory loblolly pine seedling crops. Various species...
An Educational Game for Learning Human Immunology: What Do Students Learn and How Do They Perceive?
ERIC Educational Resources Information Center
Cheng, Meng-Tzu; Su, TzuFen; Huang, Wei-Yu; Chen, Jhih-Hao
2014-01-01
The scientific concepts of human immunology are inherently complicated and extremely difficult to understand. Hence, this study reports on the development of an educational game entitled "Humunology" and examines the impact of using "Humunology" for learning how the body's defense system works. A total of 132 middle school…
Joao A. N. Filipe; Richard C. Cobb; Ross K. Meentemeyer; Christopher A. Lee; Yana S. Valachovic; Alex R. Cook; David M. Rizzo; Christopher A. Gilligan
2012-01-01
Exotic pathogens and pests threaten ecosystem service, biodiversity, and crop security globally. If an invasive agent can disperse asymptomatically over long distances, multiple spatial and temporal scales interplay, making identification of effective strategies to regulate, monitor, and control disease extremely difficult. The management of outbreaks is also...
Chapter 19: The carbon isotope composition of plants and soils as biomarkers of pollution
DE Pataki; JT Eanderson; W Want; MK Herzenach; NE Grulke
2010-01-01
Urban environments have been compared to the global environment predicted at the end of the twenty-first century, in that urban areas are currently experiencing elevated atmospheric C02 concentrations, warmer temperatures, increased nitrogen loads, and elevated concentrations of pollutants (Grimm et al. 2000). It is extremely difficult to predict...
Learning in LAMS: Lesson from a Student Teacher Exploring Gene Ethics
ERIC Educational Resources Information Center
Dennis, Carina
2012-01-01
Due to its complex and microscopic nature, genetics is a difficult subject for many learners to conceptually grasp. Graphics, animation and video material can be extremely helpful to their understanding. A wealth of educational online content about genetics has been created over the past decade in the wake of the human genome being sequenced.…
NASA Astrophysics Data System (ADS)
Gong, Fei; Di, Bangrang; Wei, Jianxin; Ding, Pinbo; Shuai, Da
2018-03-01
The presence of clay minerals can alter the elastic behaviour of reservoir rocks significantly as the type of clay minerals, their volume and distribution, and their orientation control the shale's intrinsic anisotropic behaviours. Clay minerals are the most abundant materials in shale, and it has been proven extremely difficult to measure the elastic properties of natural shale by means of a single variable (in this case, the type of clay minerals), due to the influences of multiple factors, including water, TOC content and complex mineral compositions. We used quartz, clay (kaolinite, illite and smectite), carbonate and kerogen extract as the primary materials to construct synthetic shale with different clay minerals. Ultrasonic experiments were conducted to investigate the anisotropy of velocity and mechanical properties in dry synthetic and natural shale as a function of confining pressure. Velocities in synthetic shale are sensitive to the type of clay minerals, possibly due to the different structures of the clay minerals. The velocities increase with confining pressure and show higher rate of velocity increase at low pressures, and P-wave velocity is usually more sensitive than S-wave velocity to confining pressure according to our results. Similarly, the dynamic Young's modulus and Poisson's ratio increase with applied pressure, and the results also reveal that E11 is always larger than E33 and ν31 is smaller than ν12. Velocity and mechanical anisotropy decrease with increasing stress, and are sensitive to stress and the type of clay minerals. However, the changes of mechanical anisotropy with applied stress are larger compared with the velocity anisotropy, indicating that mechanical properties are more sensitive to the change of rock properties.
Effects of physical aging on long-term behavior of composites
NASA Technical Reports Server (NTRS)
Brinson, L. Catherine
1993-01-01
The HSCT plane, envisioned to have a lifetime of over 60,000 flight hours and to travel at speeds in excess of Mach 2, is the source of intensive study at NASA. In particular, polymer matrix composites are being strongly considered for use in primary and secondary structures due to their high strength to weight ratio and the options of property tailoring. However, an added difficulty in the use of polymer based materials is that their properties change significantly over time, especially at the elevated temperatures that will be experienced during flight, and prediction of properties based on irregular thermal and mechanical loading is extremely difficult. This study focused on one aspect of long-term polymer composite behavior: physical aging. When a polymer is cooled to below its glass transition temperature, the material is not in thermodynamic equilibrium and the free volume and enthalpy evolve over time to approach their equilibrium values. During this time, the mechanical properties change significantly and this change is termed physical aging. This work begins with a review of the concepts of physical aging on a pure polymer system. The effective time theory, which can be used to predict long term behavior based on short term data, is mathematically formalized. The effects of aging to equilibrium are proven and discussed. The theory developed for polymers is then applied first to a unidirectional composite, then to a general laminate. Comparison to experimental data is excellent. It is shown that the effects of aging on the long-term properties of composites can be counter-intuitive, stressing the importance of the development and use of a predictive theory to analyze structures.
DOE Office of Scientific and Technical Information (OSTI.GOV)
Paton, Chad; Schiller, Martin; Bizzarro, Martin, E-mail: chadpaton@gmail.com, E-mail: schiller@snm.ku.dk, E-mail: bizzarro@snm.ku.dk
2013-02-01
The existence of correlated nucleosynthetic heterogeneities in solar system reservoirs is now well demonstrated for numerous nuclides. However, it has proven difficult to discriminate between the two disparate processes that can explain such correlated variability: incomplete mixing of presolar material or secondary processing of a well-mixed disk. Using stepwise acid-leaching of the Ivuna CI-chondrite, we show that unlike other nuclides such as {sup 54}Cr and {sup 50}Ti, Sr-isotope variability is the result of a carrier depleted in {sup 84}Sr. The carrier is most likely presolar SiC, which is known to have both high Sr-concentrations relative to solar abundances and extremelymore » depleted {sup 84}Sr compositions. Thus, variability in {sup 84}Sr in meteorites and their components can be attributed to varying contributions from presolar SiC. The observed {sup 84}Sr excesses in calcium-aluminum refractory inclusions (CAIs) suggest their formation from an SiC-free gaseous reservoir, whereas the {sup 84}Sr depletions present in differentiated meteorites require their formation from material with an increased concentration of SiC relative to CI chondrites. The presence of a positive correlation between {sup 84}Sr and {sup 54}Cr, despite being hosted in carriers of negative and positive anomalies, respectively, is not compatible with incomplete mixing of presolar material but instead suggests that the solar system's nucleosynthetic heterogeneity reflects selective thermal processing of dust. Based on vaporization experiments of SiC under nebular conditions, the lack of SiC material in the CAI-forming gas inferred from our data requires that the duration of thermal processing of dust resulting in the vaporization of CAI precursors was extremely short-lived, possibly lasting only hours to days.« less
Kegel, Jan; Zubialevich, Vitaly Z; Schmidt, Michael; Povey, Ian M; Pemble, Martyn E
2018-05-30
Due to the abundance of intrinsic defects in zinc oxide (ZnO), the material properties are often governed by same. Knowledge of the defect chemistry has proven to be highly important, especially in terms of the photocatalytic degradation of pollutants. Given the fact that defect-free materials or structures exhibiting only one type of defect are extremely difficult to produce, it is necessary to evaluate what influence various defects may have when present together in the material. In this study, intentionally defect-rich ZnO nanorod (NR) arrays are grown using a simple low-temperature solution-based growth technique. Upon changing the defect chemistry using rapid thermal annealing (RTA) the material properties are carefully assessed and correlated to the resulting photocatalytic properties. Special focus is put on the investigation of these properties for samples showing strong orange photoluminescence (PL). It is shown that intense orange emitting NR arrays exhibit improved dye-degradation rates under UV-light irradiation. Furthermore, strong dye-adsorption has been observed for some samples. This behavior is found to stem from a graphitic surface structure (e.g., shell) formed during RTA in vacuum. Since orange-luminescent samples also exhibit an enhancement of the dye adsorption a possible interplay and synergy of these two defects is elucidated. Additionally, evidence is presented suggesting that in annealed ZnO NRs structural defects may be responsible for the often observed PL emission at 3.31 eV. However, a clear correlation with the photocatalytic properties could not be established for these defects. Building on the specific findings presented here, this study also presents some more general guidelines which, it is suggested, should be employed when assessing the photocatalytic properties of defect-rich ZnO.
NASA Technical Reports Server (NTRS)
Petro, N. E.
2012-01-01
The South Pole-Aitken Basin (SPA) is the largest, deepest, and oldest identified basin on the Moon and contains surfaces that are unique due to their age, composition, and depth of origin in the lunar crust [1-3] (Figure 1). SPA has been a target of interest as an area for robotic sample return in order to determine the age of the basin and the composition and origin of its interior [3-6]. As part of the investigation into the origin of SPA materials there have been several efforts to estimate the likely provenance of regolith material in central SPA [5, 6]. These model estimates suggest that, despite the formation of basins and craters following SPA, the regolith within SPA is dominated by locally derived material. An assumption inherent in these models has been that the locally derived material is primarily SPA impact-melt as opposed to local basement material (e.g. unmelted lower crust). However, the definitive identification of SPA derived impact melt on the basin floor, either by remote sensing [2, 7] or via photogeology [8] is extremely difficult due to the number of subsequent impacts and volcanic activity [3, 4]. In order to identify where SPA produced impact melt may be located, it is important to constrain both how much melt would have been produced in a basin forming impact and the likely source of such melted material. Models of crater and basin formation [9, 10] present clear rationale for estimating the possible volumes and sources of impact melt produced during SPA formation. However, if SPA formed as the result of an oblique impact [11, 12], the volume and depth of origin of melted material could be distinct from similar material in a vertical impact [13].
Pediatric material properties: a review of human child and animal surrogates.
Franklyn, Melanie; Peiris, Sujanie; Huber, Christina; Yang, King H
2007-01-01
Because pediatric tissue is difficult for researchers to obtain, the biomechanical responses of adult humans have been studied much more extensively than those of children. Piglets, chimpanzees, and other animals have been used as child surrogates, but the tissue properties and responses to impact forces obtained from these animals may not directly correlate with the human child, and this correlation is not well understood. Consequently, only a handful of human pediatric tissue properties are known. Child anthropomorphic test devices employed in automotive safety have been developed largely by scaling data obtained from adult human cadaveric tests, where various scaling methods have been used to account for differences in geometry, material properties, or a combination of these two parameters. Similar scaling techniques have also been implemented to develop injury assessment reference values for child anthropomorphic test devices. Nevertheless, these scaling techniques have not yet proven to be accurate, in part because of the lack of pediatric data. In this review, the properties of pediatric human and animal surrogate tissue that have been mechanically tested are evaluated. It was found that most of the pediatric tissue that has previously been tested pertains to the head, neck, cervical spine, and extremities. It is evident that some body regions, such as the head and neck, have been tested to some extent since injuries to these regions are critical from an injury perspective. On the other hand, there is limited pediatric data available for the thorax, abdomen, thoracic and lumbar spines and fetal-related tissue. This review presents the pediatric data available in the literature and highlights the body regions where further testing is needed.
de Vos, Cecile C; Meier, Kaare; Zaalberg, Paul Brocades; Nijhuis, Harold J A; Duyvendak, Wim; Vesper, Jan; Enggaard, Thomas P; Lenders, Mathieu W P M
2014-11-01
Painful diabetic neuropathy (PDN) is a peripheral neuropathic pain condition that is often difficult to relieve. Spinal cord stimulation (SCS) is a proven effective therapy for various types of mixed neuropathic conditions, yet effectiveness of SCS treatment for PDN is not well established. To our knowledge, ours is the first multicentre randomized controlled trial investigating the effectiveness of SCS in patients with PDN. Sixty patients with PDN in the lower extremities refractory to conventional medical therapy were enrolled and followed for 6 months. They were randomized 2:1 to best conventional medical practice with (SCS group) or without (control group) additional SCS therapy, and both groups were assessed at regular intervals. At each follow-up visit, the EuroQoL 5D, the short form McGill Pain Questionnaire (SF-MPQ) and a visual analogue scale (VAS, ranging 0-100) to measure pain intensity were recorded. The average VAS score for pain intensity was 73 in the SCS group and 67 in the control group at baseline. After 6 months of treatment, the average VAS score was significantly reduced to 31 in the SCS group (P<.001) and remained 67 (P=.97) in the control group. The SF-MPQ and EuroQoL 5D questionnaires also showed that patients in the SCS group, unlike those in the control group, experienced reduced pain and improved health and quality of life after 6 months of treatment. In patients with refractory painful diabetic neuropathy, spinal cord stimulation therapy significantly reduced pain and improved quality of life. Copyright © 2014 International Association for the Study of Pain. Published by Elsevier B.V. All rights reserved.
Consistent interactive segmentation of pulmonary ground glass nodules identified in CT studies
NASA Astrophysics Data System (ADS)
Zhang, Li; Fang, Ming; Naidich, David P.; Novak, Carol L.
2004-05-01
Ground glass nodules (GGNs) have proved especially problematic in lung cancer diagnosis, as despite frequently being malignant they characteristically have extremely slow rates of growth. This problem is further magnified by the small size of many of these lesions now being routinely detected following the introduction of multislice CT scanners capable of acquiring contiguous high resolution 1 to 1.25 mm sections throughout the thorax in a single breathhold period. Although segmentation of solid nodules can be used clinically to determine volume doubling times quantitatively, reliable methods for segmentation of pure ground glass nodules have yet to be introduced. Our purpose is to evaluate a newly developed computer-based segmentation method for rapid and reproducible measurements of pure ground glass nodules. 23 pure or mixed ground glass nodules were identified in a total of 8 patients by a radiologist and subsequently segmented by our computer-based method using Markov random field and shape analysis. The computer-based segmentation was initialized by a click point. Methodological consistency was assessed using the overlap ratio between 3 segmentations initialized by 3 different click points for each nodule. The 95% confidence interval on the mean of the overlap ratios proved to be [0.984, 0.998]. The computer-based method failed on two nodules that were difficult to segment even manually either due to especially low contrast or markedly irregular margins. While achieving consistent manual segmentation of ground glass nodules has proven problematic most often due to indistinct boundaries and interobserver variability, our proposed method introduces a powerful new tool for obtaining reproducible quantitative measurements of these lesions. It is our intention to further document the value of this approach with a still larger set of ground glass nodules.
A method for probing the mutational landscape of amyloid structure.
O'Donnell, Charles W; Waldispühl, Jérôme; Lis, Mieszko; Halfmann, Randal; Devadas, Srinivas; Lindquist, Susan; Berger, Bonnie
2011-07-01
Proteins of all kinds can self-assemble into highly ordered β-sheet aggregates known as amyloid fibrils, important both biologically and clinically. However, the specific molecular structure of a fibril can vary dramatically depending on sequence and environmental conditions, and mutations can drastically alter amyloid function and pathogenicity. Experimental structure determination has proven extremely difficult with only a handful of NMR-based models proposed, suggesting a need for computational methods. We present AmyloidMutants, a statistical mechanics approach for de novo prediction and analysis of wild-type and mutant amyloid structures. Based on the premise of protein mutational landscapes, AmyloidMutants energetically quantifies the effects of sequence mutation on fibril conformation and stability. Tested on non-mutant, full-length amyloid structures with known chemical shift data, AmyloidMutants offers roughly 2-fold improvement in prediction accuracy over existing tools. Moreover, AmyloidMutants is the only method to predict complete super-secondary structures, enabling accurate discrimination of topologically dissimilar amyloid conformations that correspond to the same sequence locations. Applied to mutant prediction, AmyloidMutants identifies a global conformational switch between Aβ and its highly-toxic 'Iowa' mutant in agreement with a recent experimental model based on partial chemical shift data. Predictions on mutant, yeast-toxic strains of HET-s suggest similar alternate folds. When applied to HET-s and a HET-s mutant with core asparagines replaced by glutamines (both highly amyloidogenic chemically similar residues abundant in many amyloids), AmyloidMutants surprisingly predicts a greatly reduced capacity of the glutamine mutant to form amyloid. We confirm this finding by conducting mutagenesis experiments. Our tool is publically available on the web at http://amyloid.csail.mit.edu/. lindquist_admin@wi.mit.edu; bab@csail.mit.edu.
Joshi, Nikita; Lira, Alena; Mehta, Ninfa; Paladino, Lorenzo; Sinert, Richard
2013-01-01
Understanding history, physical examination, and ultrasonography (US) to diagnose extremity fractures compared with radiography has potential benefits of decreasing radiation exposure, costs, and pain and improving emergency department (ED) resource management and triage time. The authors performed two electronic searches using PubMed and EMBASE databases for studies published between 1965 to 2012 using a strategy based on the inclusion of any patient presenting with extremity injuries suspicious for fracture who had history and physical examination and a separate search for US performed by an emergency physician (EP) with subsequent radiography. The primary outcome was operating characteristics of ED history, physical examination, and US in diagnosing radiologically proven extremity fractures. The methodologic quality of the studies was assessed using the quality assessment of studies of diagnostic accuracy tool (QUADAS-2). Nine studies met the inclusion criteria for history and physical examination, while eight studies met the inclusion criteria for US. There was significant heterogeneity in the studies that prevented data pooling. Data were organized into subgroups based on anatomic fracture locations, but heterogeneity within the subgroups also prevented data pooling. The prevalence of fracture varied among the studies from 22% to 70%. Upper extremity physical examination tests have positive likelihood ratios (LRs) ranging from 1.2 to infinity and negative LRs ranging from 0 to 0.8. US sensitivities varied between 85% and 100%, specificities varied between 73% and 100%, positive LRs varied between 3.2 and 56.1, and negative LRs varied between 0 and 0.2. Compared with radiography, EP US is an accurate diagnostic test to rule in or rule out extremity fractures. The diagnostic accuracy for history and physical examination are inconclusive. Future research is needed to understand the accuracy of ED US when combined with history and physical examination for upper and lower extremity fractures. © 2013 by the Society for Academic Emergency Medicine.
Cumulative hazard: The case of nuisance flooding
NASA Astrophysics Data System (ADS)
Moftakhari, Hamed R.; AghaKouchak, Amir; Sanders, Brett F.; Matthew, Richard A.
2017-02-01
The cumulative cost of frequent events (e.g., nuisance floods) over time may exceed the costs of the extreme but infrequent events for which societies typically prepare. Here we analyze the likelihood of exceedances above mean higher high water and the corresponding property value exposure for minor, major, and extreme coastal floods. Our results suggest that, in response to sea level rise, nuisance flooding (NF) could generate property value exposure comparable to, or larger than, extreme events. Determining whether (and when) low cost, nuisance incidents aggregate into high cost impacts and deciding when to invest in preventive measures are among the most difficult decisions for policymakers. It would be unfortunate if efforts to protect societies from extreme events (e.g., 0.01 annual probability) left them exposed to a cumulative hazard with enormous costs. We propose a Cumulative Hazard Index (CHI) as a tool for framing the future cumulative impact of low cost incidents relative to infrequent extreme events. CHI suggests that in New York, NY, Washington, DC, Miami, FL, San Francisco, CA, and Seattle, WA, a careful consideration of socioeconomic impacts of NF for prioritization is crucial for sustainable coastal flood risk management.
Infrared dermal thermography on diabetic feet soles to predict ulcerations: a case study
NASA Astrophysics Data System (ADS)
Liu, Chanjuan; van der Heijden, Ferdi; Klein, Marvin E.; van Baal, Jeff G.; Bus, Sicco A.; van Netten, Jaap J.
2013-03-01
Diabetic foot ulceration is a major complication for patients with diabetes mellitus. If not adequately treated, these ulcers may lead to foot infection, and ultimately to lower extremity amputation, which imposes a major burden to society and great loss in health-related quality of life for patients. Early identification and subsequent preventive treatment have proven useful to limit the incidence of foot ulcers and lower extremity amputation. Thus, the development of new diagnosis tools has become an attractive option. The ultimate objective of our project is to develop an intelligent telemedicine monitoring system for frequent examination on patients' feet, to timely detect pre-signs of ulceration. Inflammation in diabetic feet can be an early and predictive warning sign for ulceration, and temperature has been proven to be a vicarious marker for inflammation. Studies have indicated that infrared dermal thermography of foot soles can be one of the important parameters for assessing the risk of diabetic foot ulceration. This paper covers the feasibility study of using an infrared camera, FLIR SC305, in our setup, to acquire the spatial thermal distribution on the feet soles. With the obtained thermal images, automated detection through image analysis was performed to identify the abnormal increased/decreased temperature and assess the risk for ulceration. The thermography for feet soles of patients with diagnosed diabetic foot complications were acquired before the ordinary foot examinations. Assessment from clinicians and thermography were compared and follow-up measurements were performed to investigate the prediction. A preliminary case study will be presented, indicating that dermal thermography in our proposed setup can be a screening modality to timely detect pre-signs of ulceration.
Loading Considerations for Implementing Friction STIR Welding for Large Diameter Tank Fabrication
NASA Technical Reports Server (NTRS)
Adams, Glynn
1998-01-01
The main objectives of the research presented here are to determine the reaction loads associated with friction stir welding (FSW) and to determine the suitability of an existing welding fixture for implementing this welding process in the fabrication of large diameter tanks. Friction stir welding is a relatively new process which is being investigated as a method for joining aluminum alloys. The aluminum-lithium alloy, Al-Li 2195, which is being used to fabricate the super-light-weight shuttle external tank has proven difficult to join using fusion techniques. Therefore, FSW and its potential applicability to joining Al-Li 2195 are of particular interest to NASA.
Reconfigurable and writable magnetic charge crystals
Wang, Yong-Lei; Xiao, Zhi-Li; Kwok, Wai-Kwong
2017-07-18
Artificial ices enable the study of geometrical frustration by design and through direct observation. It has, however, proven difficult to achieve tailored long-range ordering of their diverse configurations, limiting both fundamental and applied research directions. An artificial spin structure design is described that produces a magnetic charge ice with tunable long-range ordering of eight different configurations. A technique is also developed to precisely manipulate the local magnetic charge states and demonstrate write-read-erase multi-functionality at room temperature. This globally reconfigurable and locally writable magnetic charge ice provides a setting for designing magnetic monopole defects, tailoring magnetics and controlling the properties of other two-dimensional materials.
Smart phones: platform enabling modular, chemical, biological, and explosives sensing
NASA Astrophysics Data System (ADS)
Finch, Amethist S.; Coppock, Matthew; Bickford, Justin R.; Conn, Marvin A.; Proctor, Thomas J.; Stratis-Cullum, Dimitra N.
2013-05-01
Reliable, robust, and portable technologies are needed for the rapid identification and detection of chemical, biological, and explosive (CBE) materials. A key to addressing the persistent threat to U.S. troops in the current war on terror is the rapid detection and identification of the precursor materials used in development of improvised explosive devices, homemade explosives, and bio-warfare agents. However, a universal methodology for detection and prevention of CBE materials in the use of these devices has proven difficult. Herein, we discuss our efforts towards the development of a modular, robust, inexpensive, pervasive, archival, and compact platform (android based smart phone) enabling the rapid detection of these materials.
NASA Technical Reports Server (NTRS)
Madavan, Nateri K.
2004-01-01
Differential Evolution (DE) is a simple, fast, and robust evolutionary algorithm that has proven effective in determining the global optimum for several difficult single-objective optimization problems. The DE algorithm has been recently extended to multiobjective optimization problem by using a Pareto-based approach. In this paper, a Pareto DE algorithm is applied to multiobjective aerodynamic shape optimization problems that are characterized by computationally expensive objective function evaluations. To improve computational expensive the algorithm is coupled with generalized response surface meta-models based on artificial neural networks. Results are presented for some test optimization problems from the literature to demonstrate the capabilities of the method.
Rewritable artificial magnetic charge ice
Wang, Yong-Lei; Xiao, Zhi-Li; Snezhko, Alexey; ...
2016-05-20
Artificial ices enable the study of geometrical frustration by design and through direct observation. However, it has proven difficult to achieve tailored long-range ordering of their diverse configurations, limiting both fundamental and applied research directions. Here, we designed an artificial spin structure that produces a magnetic charge ice with tunable long-range ordering of eight different configurations. We also developed a technique to precisely manipulate the local magnetic charge states and demonstrate write-read-erase multifunctionality at room temperature. This globally reconfigurable and locally writable magnetic charge ice could provide a setting for designing magnetic monopole defects, tailoring magnonics, and controlling the propertiesmore » of other two-dimensional materials.« less
Multigrid for Staggered Lattice Fermions
DOE Office of Scientific and Technical Information (OSTI.GOV)
Brower, Richard C.; Clark, M. A.; Strelchenko, Alexei
Critical slowing down in Krylov methods for the Dirac operator presents a major obstacle to further advances in lattice field theory as it approaches the continuum solution. Here we formulate a multi-grid algorithm for the Kogut-Susskind (or staggered) fermion discretization which has proven difficult relative to Wilson multigrid due to its first-order anti-Hermitian structure. The solution is to introduce a novel spectral transformation by the K\\"ahler-Dirac spin structure prior to the Galerkin projection. We present numerical results for the two-dimensional, two-flavor Schwinger model, however, the general formalism is agnostic to dimension and is directly applicable to four-dimensional lattice QCD.
A Substance Called Food: Long-Term Psychodynamic Group Treatment for Compulsive Overeating.
Schwartz, Deborah C; Nickow, Marcia S; Arseneau, Ric; Gisslow, Mary T
2015-07-01
Obesity has proven difficult to treat. Many approaches neglect to address the deep-rooted underlying psychological issues. This paper describes a psychodynamically oriented approach to treating compulsive overeating as an addiction. Common to all addictions is a compulsion to consume a substance or engage in a behavior, a preoccupation with using behavior and rituals, and a lifestyle marked by an inability to manage the behavior and its harmful consequences. The approach represents a shift away from primarily medical models of intervention to integrated models focusing on the psychological underpinnings of obesity. Long-term psychodynamic group psychotherapy is recommended as a primary treatment.
Trifa, Adrian; Selicean, Cristina; Moisoiu, Vlad; Frinc, Ioana; Zdrenghea, Mihnea; Tomuleasa, Ciprian
2017-01-01
Acute megakaryocytic leukemia (M7-AML) is a rare form of acute myeloid leukemia (AML), which is associated with poor prognosis. The case presented in the current report is a statement for the difficult diagnosis and clinical management of M7-AML in the context of a previous hematologic disorder of undetermined significance and associated genetic abnormalities. Probably, following the complete hematologic remission and further with induction chemotherapy plus tyrosine kinase inhibitor therapy, the clinical management of this case will be followed by a allogeneic bone marrow transplantation, the only proven therapy to improve overall survival. PMID:29089774
Study of Nickel Silicide as a Copper Diffusion Barrier in Monocrystalline Silicon Solar Cells
DOE Office of Scientific and Technical Information (OSTI.GOV)
Kale, Abhijit; Beese, Emily; Saenz, Theresa
NiSi as a conductive diffusion barrier to silicon has been studied. We demonstrate that the NiSi films formed using the single step annealing process are as good as the two step process using XRD and Raman. Quality of NiSi films formed using e-beam Ni and electroless Ni process has been compared. Incomplete surface coverage and presence of constituents other than Ni are the main challenges with electroless Ni. We also demonstrate that Cu reduces the thermal stability of NiSi films. The detection of Cu has proven to be difficult due to temperature limitations.
Economic networks: the new challenges.
Schweitzer, Frank; Fagiolo, Giorgio; Sornette, Didier; Vega-Redondo, Fernando; Vespignani, Alessandro; White, Douglas R
2009-07-24
The current economic crisis illustrates a critical need for new and fundamental understanding of the structure and dynamics of economic networks. Economic systems are increasingly built on interdependencies, implemented through trans-national credit and investment networks, trade relations, or supply chains that have proven difficult to predict and control. We need, therefore, an approach that stresses the systemic complexity of economic networks and that can be used to revise and extend established paradigms in economic theory. This will facilitate the design of policies that reduce conflicts between individual interests and global efficiency, as well as reduce the risk of global failure by making economic networks more robust.
Rewritable artificial magnetic charge ice
DOE Office of Scientific and Technical Information (OSTI.GOV)
Wang, Yong-Lei; Xiao, Zhi-Li; Snezhko, Alexey
Artificial ices enable the study of geometrical frustration by design and through direct observation. However, it has proven difficult to achieve tailored long-range ordering of their diverse configurations, limiting both fundamental and applied research directions. Here, we designed an artificial spin structure that produces a magnetic charge ice with tunable long-range ordering of eight different configurations. We also developed a technique to precisely manipulate the local magnetic charge states and demonstrate write-read-erase multifunctionality at room temperature. This globally reconfigurable and locally writable magnetic charge ice could provide a setting for designing magnetic monopole defects, tailoring magnonics, and controlling the propertiesmore » of other two-dimensional materials.« less
Extremes of the jet–accretion power relation of blazars, as explored by NuSTAR
Sbarrato, T.; Ghisellini, G.; Tagliaferri, G.; ...
2016-07-18
Hard X-ray observations are crucial to study the non-thermal jet emission from high-redshift, powerful blazars. We observed two bright z > 2 flat spectrum radio quasars (FSRQs) in hard X-rays to explore the details of their relativistic jets and their possible variability. S5 0014+81 (at z = 3.366) and B0222+185 (at z=2.690) have been observed twice by the Nuclear Spectroscopic Telescope Array (NuSTAR) simultaneously with Swift/XRT, showing different variability behaviors. We found that NuSTAR is instrumental to explore the variability of powerful high-redshift blazars, even when no gamma-ray emission is detected. The two sources have proven to have respectively themore » most luminous accretion disk and the most powerful jet among known blazars. Furthermore, thanks to these properties, they are located at the extreme end of the jet-accretion disk relation previously found for gamma-ray detected blazars, to which they are consistent.« less
Microbial enzymes with special characteristics for biotechnological applications.
Nigam, Poonam Singh
2013-08-23
This article overviews the enzymes produced by microorganisms, which have been extensively studied worldwide for their isolation, purification and characterization of their specific properties. Researchers have isolated specific microorganisms from extreme sources under extreme culture conditions, with the objective that such isolated microbes would possess the capability to bio-synthesize special enzymes. Various Bio-industries require enzymes possessing special characteristics for their applications in processing of substrates and raw materials. The microbial enzymes act as bio-catalysts to perform reactions in bio-processes in an economical and environmentally-friendly way as opposed to the use of chemical catalysts. The special characteristics of enzymes are exploited for their commercial interest and industrial applications, which include: thermotolerance, thermophilic nature, tolerance to a varied range of pH, stability of enzyme activity over a range of temperature and pH, and other harsh reaction conditions. Such enzymes have proven their utility in bio-industries such as food, leather, textiles, animal feed, and in bio-conversions and bio-remediations.
NASA Technical Reports Server (NTRS)
1973-01-01
As part of the Shuttle Exhaust Effects Panel (SEEP) program for fiscal year 1973, a limited study was performed to determine the feasibility of minimizing the environmental impact associated with the operation of the solid rocket booster motors (SRBMs) in projected space shuttle launches. Eleven hypothetical and two existing limited-experience propellants were evaluated as possible alternates to a well-proven state-of-the-art reference propellant with respect to reducing emissions of primary concern: namely, hydrogen chloride (HCl) and aluminum oxide (Al2O3). The study showed that it would be possible to develop a new propellant to effect a considerable reduction of HCl or Al2O3 emissions. At the one extreme, a 23% reduction of HCl is possible along with a ll% reduction in Al2O3, whereas, at the other extreme, a 75% reduction of Al2O3 is possible, but with a resultant 5% increase in HCl.
Extremes of the jet–accretion power relation of blazars, as explored by NuSTAR
DOE Office of Scientific and Technical Information (OSTI.GOV)
Sbarrato, T.; Ghisellini, G.; Tagliaferri, G.
Hard X-ray observations are crucial to study the non-thermal jet emission from high-redshift, powerful blazars. We observed two bright z > 2 flat spectrum radio quasars (FSRQs) in hard X-rays to explore the details of their relativistic jets and their possible variability. S5 0014+81 (at z = 3.366) and B0222+185 (at z=2.690) have been observed twice by the Nuclear Spectroscopic Telescope Array (NuSTAR) simultaneously with Swift/XRT, showing different variability behaviors. We found that NuSTAR is instrumental to explore the variability of powerful high-redshift blazars, even when no gamma-ray emission is detected. The two sources have proven to have respectively themore » most luminous accretion disk and the most powerful jet among known blazars. Furthermore, thanks to these properties, they are located at the extreme end of the jet-accretion disk relation previously found for gamma-ray detected blazars, to which they are consistent.« less
Neurological consequences of systemic inflammation in the premature neonate.
Patra, Aparna; Huang, Hong; Bauer, John A; Giannone, Peter J
2017-06-01
Despite substantial progress in neonatal care over the past two decades leading to improved survival of extremely premature infants, extreme prematurity continues to be associated with long term neurodevelopmental impairments. Cerebral white matter injury is the predominant form of insult in preterm brain leading to adverse neurological consequences. Such brain injury pattern and unfavorable neurologic sequelae is commonly encountered in premature infants exposed to systemic inflammatory states such as clinical or culture proven sepsis with or without evidence of meningitis, prolonged mechanical ventilation, bronchopulmonary dysplasia, necrotizing enterocolitis and chorioamnionitis. Underlying mechanisms may include cytokine mediated processes without direct entry of pathogens into the brain, developmental differences in immune response and complex neurovascular barrier system that play a critical role in regulating the cerebral response to various systemic inflammatory insults in premature infants. Understanding of these pathologic mechanisms and clinical correlates of such injury based on serum biomarkers or brain imaging findings on magnetic resonance imaging will pave way for future research and translational therapeutic opportunities for the developing brain.
The Correlation between Radon Emission Concentration and Subsurface Geological Condition
NASA Astrophysics Data System (ADS)
Kuntoro, Yudi; Setiawan, Herru L.; Wijayanti, Teni; Haerudin, Nandi
2018-03-01
Exploration activities with standard methods have already encountered many obstacles in the field. Geological survey is often difficult to find outcrop because they are covered by vegetation, alluvial layer or as a result of urban development and housing. Seismic method requires a large expense and licensing in the use of dynamite is complicated. Method of gravity requires the operator to go back (looping) to the starting point. Given some of these constraints, therefore it needs a solution in the form of new method that can work more efficiently with less cost. Several studies in various countries have shown a correlation between the presence of hydrocarbons and Radon gas concentration in the earth surface. By utilizing the properties of Radon that can migrate to the surface, the value of Radon concentration in the surface is suggested to provide information about the subsurface structure condition. Radon is the only radioactive substance that gas-phased at atmospheric temperature. It is very abundant in the earth mantle. The vast differences of temperatures and pressures between the mantle and the earth crust cause the convection flow toward earth surface. Radon in gas phase will be carried by convection flow to the surface. The quantity of convection currents depend on the porosity and permeability of rocks where Radon travels within, so that Radon concentration in the earth surface delineates the porosity and permeability of subsurface rock layers. Some measurements were carried out at several locations with various subsurface geological conditions, including proven oil fields, proven geothermal field, and frontier area as a comparison. These measurements show that the average and the background concentration threshold in the proven oil field (11,200 Bq/m3) and proven geothermal field (7,820 Bq/m3) is much higher than the quantity in frontier area (329 and 1,620 Bq/m3). Radon concentration in the earth surface is correlated with the presence of geological faults. Peak concentrations of Radon takes place along the fault.
Ahmed, Nauman; Hassan, Maaz Ul; Tahira, Maham; Samad, Abdul; Rana, Hamad Naeem
2018-01-01
To evaluate the intra-operative scoring system to predict difficult cholecystectomy and conversion to open surgery. This descriptive study was conducted from March 2016 to August, 2016 in the Department of Surgery, Shalimar Hospital. The study recruited 120 patients of either gender, age greater than 18 years and indicated for laparoscopic cholecystectomy (LC). Intra-operatively all patients were evaluated using the new scoring system. The scoring system included five aspects; appearance and adhesion of Gall Bladder (GB), distension or contracture degree of GB, ease in access, local or septic complications, and time required for cystic artery and duct identification. The scoring system ranges from 0 to 10, classified as score of <2 being considered easy, 2 to 4 moderate, 5-7 very difficult, and 8 to 10, extreme. Patient demographic data (i.e. age, gender), co-morbidities, intra-operative scores using the scoring system and conversion to open were recorded. The data was analysed using statistical analysis software SPSS (IBM). Among one hundred and twenty participants, sixty seven percent were females and the mean age (years) was 43.05 ± 14.16. Co-morbidities were present in twenty percent patients with eleven diagnosed with diabetes, six with hypertension and five with both hypertension and diabetes. The conversion rate to open surgery was 6.7%. The overall mean intra-operative scores were 3.52 ± 2.23; however significant difference was seen in mean operative score of converted to open and those not converted to open (8.00 ± 0.92 Vs. 3.20 V 1.92; p-value = 0.001). Among eight cases converted to open, three (37.5%) were in very difficult category while five (62.5%) were in extreme category. Moreover, age greater than 40 years and being diabetic were also the risk factors for conversion to open surgery. The new intra-operative scoring system is a valuable assessment tool to predict difficult laparoscopic cholecystectomy and conversion parameters to open surgery and its utility could improve patient's clinical outcome indicated for laparoscopic cholecystectomy.
ERIC Educational Resources Information Center
Harrison, Jason Gordon
2013-01-01
Quantum mechanical (QM) and molecular docking methods are used to probe systems of biological and synthetic interest. Probing interactions of nucleobases within proteins, and properly modeling said interactions toward novel nucleobase development, is extremely difficult, and of great utility in RNA interference (RNAi) therapeutics. The issues in…
F. Rodríguez y Silva; J.R. Molina Martínez; Armando González-Cabán
2014-01-01
Traditional uses of the forest (timber, forage) have been giving way to other uses more in demand (recreation, ecosystem services). An observable consequence of this process of forest land use conversion is an increase in more difficult and extreme wildfires. Wildland forest management and protection program budgets are limited, and managers are requesting help in...
Hurricane impacts on forest resources in the Eastern United States: a post-sandy assessment
Greg C. Liknes; Susan J. Crocker; Randall S. Morin; Brian F. Walters
2015-01-01
Extreme weather events play a role in shaping the composition and structure of forests. Responding to and mitigating a storm event in a forested environment requires information about the location and severity of tree damage. However, this information can be difficult to obtain immediately following an event. Post-storm assessments using regularly collected forest...
Dynamics of cracks in disordered materials
NASA Astrophysics Data System (ADS)
Bonamy, Daniel
2017-05-01
Predicting when rupture occurs or cracks progress is a major challenge in numerous fields of industrial, societal, and geophysical importance. It remains largely unsolved: stress enhancement at cracks and defects, indeed, makes the macroscale dynamics extremely sensitive to the microscale material disorder. This results in giant statistical fluctuations and non-trivial behaviors upon upscaling, difficult to assess via the continuum approaches of engineering.
Tibetan-English Dictionary of Modern Tibetan. Bibliotheca Himalayica, Series II, Vol. 9.
ERIC Educational Resources Information Center
Goldstein, Melvyn C., Ed.
Recent political events have triggered a revolution in the Tibetan language. The entrance of Tibet into the world arena of politics, science and technology has led to the creation of thousands of new lexical items in a relatively short period of time. Because of these changes, modern literary Tibetan is extremely difficult for non-Tibetans to…
USDA-ARS?s Scientific Manuscript database
Immunoassays contribute greatly to veterinary drug residue analysis and food safety, but there are no reported immunoassays on simultaneously detecting MQCA and QCA, the marker residues for carbadox and olaquindox. It is extremely difficult to produce broad-specificity antibodies that bind both res...
Integrated Spacesuit Audio System Enhances Speech Quality and Reduces Noise
NASA Technical Reports Server (NTRS)
Huang, Yiteng Arden; Chen, Jingdong; Chen, Shaoyan Sharyl
2009-01-01
A new approach has been proposed for increasing astronaut comfort and speech capture. Currently, the special design of a spacesuit forms an extreme acoustic environment making it difficult to capture clear speech without compromising comfort. The proposed Integrated Spacesuit Audio (ISA) system is to incorporate the microphones into the helmet and use software to extract voice signals from background noise.
USDA-ARS?s Scientific Manuscript database
The emerald ash borer, Agrilus planipennis Fairmaire, an invasive beetle from Asia causing large scale ash (Fraxinus spp.) mortality in North America, has been extremely difficult to rear in the laboratory because of its long life cycle and cryptic nature of immature stages. This lack of effective ...
ERIC Educational Resources Information Center
Dahl, Robyn Mieko; Droser, Mary L.
2016-01-01
University earth science departments seeking to establish meaningful geoscience outreach programs often pursue large-scale, grant-funded programs. Although this type of outreach is highly successful, it is also extremely costly, and grant funding can be difficult to secure. Here, we present the Geoscience Education Outreach Program (GEOP), a…
2007-08-02
Societal stigmas against gangs and gang- deportees from the United States have made the process of leaving a gang extremely difficult. A recent...often unwilling to hire them. Tattooed former gang members, especially returning deportees from the United States who are often native English...recipients of deportees on a per capita basis. For all Central American countries, with the exception of Panama, those deported on criminal grounds
Michelle F. Tacconelli; Edward F. Loewenstein
2012-01-01
Natural resource managers must often balance multiple objectives on a single property. When these objectives are seemingly conflicting, the managerâs job can be extremely difficult and complex. This paper presents a decision support tool, designed to aid land managers in optimizing wildlife habitat needs while accomplishing additional objectives such as ecosystem...
Relevance of antarctic microbial ecosystems to exobiology
NASA Technical Reports Server (NTRS)
Mckay, Christopher P.
1993-01-01
Antarctic microbial ecosystems which provide biological and physical analogs that can be used in exobiology are studied. Since the access to extraterrestrial habitats is extremely difficult, terrestrial analogs represent the best opportunity for both formulation and preliminary testing of hypothesis about life. Antarctica, as one of few suitable environments on earth is considered to be a major locus of progress in exobiology.
ERIC Educational Resources Information Center
Rajulton, Fernando; Ravanera, Zenaida R.; Beaujot, Roderic
2007-01-01
Social cohesion is a concept difficult to define and to measure. As there can be many definitions, so there can be many measurements. The main problem, either in defining or measuring the concept, is its multilevel and multidimensional nature. At one extreme, "country" is the most commonly used level to view social cohesion but…
ERIC Educational Resources Information Center
Reyes Paulino, Lisette G.
2012-01-01
An epidemic such as diabetes is an extremely complex public health, economic and social problem that is difficult to solve through medical expertise alone. Evidence-based models for improving healthcare delivery systems advocate educating patients to become more active participants in their own care. This shift demands preparing chronically ill…
Heterotopic Prostate at Autopsy- An Unusual Mass at the Dome of the Urinary Bladder
Munde, Shital; Phadnis, Priyanka
2017-01-01
Heterotopic prostate in the dome of the urinary bladder is extremely rare and difficult to diagnose. It is often mistaken for neoplastic masses and histopathological examination is warranted for diagnosis. We report an autopsy case of an ectopic prostate at the dome of the bladder which mimicked a neoplasm on gross pathology. PMID:29207717
Investigating the Stability of Benzoyl Peroxide in Over-the-Counter Acne Medications
ERIC Educational Resources Information Center
Kittredge, Marina Canepa; Kittredge, Kevin W.; Sokol, Melissa S.; Sarquis, Arlyne M.; Sennet, Laura M.
2008-01-01
One of the most commonly used ingredients in over-the-counter acne treatments in cream, gel, and wash form is benzoyl peroxide. It is an anti-bacterial agent that kills the bacterium ("Propionibacterium acne") involved in the formation of acne. The formulation of these products is extremely difficult owing to the instability of benzoyl peroxide.…
ERIC Educational Resources Information Center
Adduci, Stacy B.
2017-01-01
Improving the nation's math prowess and preparing the youth to be college or career ready, may need to be solved by a culmination of theories from different perspectives. As the controversial meshing hypothesis contends that teachers should present information according to each students' learning styles; this can be extremely difficult in a…
Influence of sleep deprivation and auditory intensity on reaction time and response force.
Włodarczyk, Dariusz; Jaśkowski, Piotr; Nowik, Agnieszka
2002-06-01
Arousal and activation are two variables supposed to underlie change in response force. This study was undertaken to explain these roles, specifically, for strong auditory stimuli and sleep deficit. Loud auditory stimuli can evoke phasic overarousal whereas sleep deficit leads to general underarousal. Moreover, Van der Molen and Keuss (1979, 1981) showed that paradoxically long reaction times occurred with extremely strong auditory stimuli when the task was difficult, e.g., choice reaction or Simon paradigm. It was argued that this paradoxical behavior related to reaction time is due to active disconnecting of the coupling between arousal and activation to prevent false responses. If so, we predicted that for extremely loud stimuli and for difficult tasks, the lengthening of reaction time should be associated with reduction of response force. The effects of loudness and sleep deficit on response time and force were investigated in three different tasks: simple response, choice response, and Simon paradigm. According to our expectation, we found a detrimental effect of sleep deficit on reaction time and on response force. In contrast to Van der Molen and Keuss, we found no increase in reaction time for loud stimuli (up to 110 dB) even on the Simon task.
Application of a fast skyline computation algorithm for serendipitous searching problems
NASA Astrophysics Data System (ADS)
Koizumi, Kenichi; Hiraki, Kei; Inaba, Mary
2018-02-01
Skyline computation is a method of extracting interesting entries from a large population with multiple attributes. These entries, called skyline or Pareto optimal entries, are known to have extreme characteristics that cannot be found by outlier detection methods. Skyline computation is an important task for characterizing large amounts of data and selecting interesting entries with extreme features. When the population changes dynamically, the task of calculating a sequence of skyline sets is called continuous skyline computation. This task is known to be difficult to perform for the following reasons: (1) information of non-skyline entries must be stored since they may join the skyline in the future; (2) the appearance or disappearance of even a single entry can change the skyline drastically; (3) it is difficult to adopt a geometric acceleration algorithm for skyline computation tasks with high-dimensional datasets. Our new algorithm called jointed rooted-tree (JR-tree) manages entries using a rooted tree structure. JR-tree delays extend the tree to deep levels to accelerate tree construction and traversal. In this study, we presented the difficulties in extracting entries tagged with a rare label in high-dimensional space and the potential of fast skyline computation in low-latency cell identification technology.
Qualification of Engineering Camera for Long-Duration Deep Space Missions
NASA Technical Reports Server (NTRS)
Ramesham, Rajeshuni; Maki, Justin N.; Pourangi, Ali M.; Lee, Steven W.
2012-01-01
Qualification and verification of advanced electronic packaging and interconnect technologies, and various other types of hardware elements for the Mars Exploration Rover s Spirit and Opportunity (MER)/Mars Science Laboratory (MSL) flight projects, has been performed to enhance the mission assurance. The qualification of hardware (engineering camera) under extreme cold temperatures has been performed with reference to various Mars-related project requirements. The flight-like packages, sensors, and subassemblies have been selected for the study to survive three times the total number of expected diurnal temperature cycles resulting from all environmental and operational exposures occurring over the life of the flight hardware, including all relevant manufacturing, ground operations, and mission phases. Qualification has been performed by subjecting above flight-like hardware to the environmental temperature extremes, and assessing any structural failures or degradation in electrical performance due to either overstress or thermal cycle fatigue. Engineering camera packaging designs, charge-coupled devices (CCDs), and temperature sensors were successfully qualified for MER and MSL per JPL design principles. Package failures were observed during qualification processes and the package redesigns were then made to enhance the reliability and subsequent mission assurance. These results show the technology certainly is promising for MSL, and especially for longterm extreme temperature missions to the extreme temperature conditions. The engineering camera has been completely qualified for the MSL project, with the proven ability to survive on Mars for 2010 sols, or 670 sols times three. Finally, the camera continued to be functional, even after 2010 thermal cycles.
DOE Office of Scientific and Technical Information (OSTI.GOV)
Guo Xiaoming
The dominated process of controlled fusion is to let nuclei gain enough kinetic energy to overcome Coulomb barrier. As a result, a fusion scheme can consider two factors in its design: to increase kinetic energy of nuclei and to alter the Coulomb barrier. Cold Fusion and Hot fusion are all one-factor schemes while Intermediate Fusion is a twofactors scheme. This made CINF kinetically superior. Cold Fusion reduces deuteron-deuteron distance, addressing Coulomb barrier, and Hot Fusion heat up plasma into extreme high temperature, addressing kinetic energy. Without enough kinetic energy made Cold Fusion skeptical. Extreme high temperature made Hot Fusion verymore » difficult to engineer. Because CIFN addresses both factors, CIFN is a more promising technique to be industrialized.« less
Complexity-aware simple modeling.
Gómez-Schiavon, Mariana; El-Samad, Hana
2018-02-26
Mathematical models continue to be essential for deepening our understanding of biology. On one extreme, simple or small-scale models help delineate general biological principles. However, the parsimony of detail in these models as well as their assumption of modularity and insulation make them inaccurate for describing quantitative features. On the other extreme, large-scale and detailed models can quantitatively recapitulate a phenotype of interest, but have to rely on many unknown parameters, making them often difficult to parse mechanistically and to use for extracting general principles. We discuss some examples of a new approach-complexity-aware simple modeling-that can bridge the gap between the small-scale and large-scale approaches. Copyright © 2018 Elsevier Ltd. All rights reserved.
Kinetic advantage of controlled intermediate nuclear fusion
NASA Astrophysics Data System (ADS)
Guo, Xiaoming
2012-09-01
The dominated process of controlled fusion is to let nuclei gain enough kinetic energy to overcome Coulomb barrier. As a result, a fusion scheme can consider two factors in its design: to increase kinetic energy of nuclei and to alter the Coulomb barrier. Cold Fusion and Hot fusion are all one-factor schemes while Intermediate Fusion is a twofactors scheme. This made CINF kinetically superior. Cold Fusion reduces deuteron-deuteron distance, addressing Coulomb barrier, and Hot Fusion heat up plasma into extreme high temperature, addressing kinetic energy. Without enough kinetic energy made Cold Fusion skeptical. Extreme high temperature made Hot Fusion very difficult to engineer. Because CIFN addresses both factors, CIFN is a more promising technique to be industrialized.
On the Performance of an Algebraic MultigridSolver on Multicore Clusters
DOE Office of Scientific and Technical Information (OSTI.GOV)
Baker, A H; Schulz, M; Yang, U M
2010-04-29
Algebraic multigrid (AMG) solvers have proven to be extremely efficient on distributed-memory architectures. However, when executed on modern multicore cluster architectures, we face new challenges that can significantly harm AMG's performance. We discuss our experiences on such an architecture and present a set of techniques that help users to overcome the associated problems, including thread and process pinning and correct memory associations. We have implemented most of the techniques in a MultiCore SUPport library (MCSup), which helps to map OpenMP applications to multicore machines. We present results using both an MPI-only and a hybrid MPI/OpenMP model.
In situ methods for Li-ion battery research: A review of recent developments
NASA Astrophysics Data System (ADS)
Harks, P. P. R. M. L.; Mulder, F. M.; Notten, P. H. L.
2015-08-01
A considerable amount of research is being directed towards improving lithium-ion batteries in order to meet today's market demands. In particular in situ investigations of Li-ion batteries have proven extremely insightful, but require the electrochemical cell to be fully compatible with the conditions of the testing method and are therefore often challenging to execute. Advantageously, in the past few years significant progress has been made with new, more advanced, in situ techniques. Herein, a comprehensive overview of in situ methods for studying Li-ion batteries is given, with the emphasis on new developments and reported experimental highlights.
Envenomation by Micrurus coral snakes in the Brazilian Amazon region: report of two cases.
Pardal, Pedro Pereira de Oliveira; Pardal, Joseana Silva de Oliveira; Gadelha, Maria Apolônia da Costa; Rodrigues, Líliam da Silva; Feitosa, Darlan Tavares; Prudente, Ana Lúcia da Costa; Fan, Hui Wen
2010-01-01
Two cases of proven coral snake bites were reported in Belém, Pará State, Brazil. The first case was a severe one caused by Micrurus surinamensis. The patient required mechanical ventilation due to acute respiratory failure. The second case showed just mild signs of envenomation caused by Micrurus filiformis. Both patients received specific Micrurus antivenom and were discharged without further complications. Coral snake bites are scarcely reported in the Amazon region and there is a broad spectrum of clinical manifestations, varying from extremely mild to those which may rapidly lead to death if the patient is not treated as soon as possible.
Collaborative Software Development in Support of Fast Adaptive AeroSpace Tools (FAAST)
NASA Technical Reports Server (NTRS)
Kleb, William L.; Nielsen, Eric J.; Gnoffo, Peter A.; Park, Michael A.; Wood, William A.
2003-01-01
A collaborative software development approach is described. The software product is an adaptation of proven computational capabilities combined with new capabilities to form the Agency's next generation aerothermodynamic and aerodynamic analysis and design tools. To efficiently produce a cohesive, robust, and extensible software suite, the approach uses agile software development techniques; specifically, project retrospectives, the Scrum status meeting format, and a subset of Extreme Programming's coding practices are employed. Examples are provided which demonstrate the substantial benefits derived from employing these practices. Also included is a discussion of issues encountered when porting legacy Fortran 77 code to Fortran 95 and a Fortran 95 coding standard.
Boykin, Robert E
2018-03-01
Patients with radiographic evidence of femoroacetabular impingement and decreased hip internal rotation have a higher rate of anterior cruciate ligament (ACL) tears. Limited internal rotation of the hip increases strain and potentially resultant fatigue failure of the ACL. Although causation has not been proven, a better understanding of the lower extremity kinetic chain may allow improved ACL prevention strategies through measures (operative or nonoperative) to improve rotation of the hip. Copyright © 2017 Arthroscopy Association of North America. Published by Elsevier Inc. All rights reserved.
Using dogs for tiger conservation and research.
Kerley, Linda L
2010-12-01
This paper is a review of the history, development and efficacy of using dogs in wildlife studies and considers the use of dogs in the research and conservation of wild tigers (Panthera tigris Linnaeus, 1758). Using scat detection dogs, scent-matching dogs, law enforcement detection dogs and protection dogs are proven methods that can be effectively used on tigers. These methods all take advantage of the dog's extremely evolved sense of smell that allows them to detect animals or animal byproducts (often the focus of tiger studies). Dogs can be trained to communicate this information to their handlers. © 2010 ISZS, Blackwell Publishing and IOZ/CAS.
Nature, nurture and epigenetics.
Crews, David; Gillette, Ross; Miller-Crews, Isaac; Gore, Andrea C; Skinner, Michael K
2014-12-01
Real life by definition combines heritability (e.g., the legacy of exposures) and experience (e.g. stress during sensitive or 'critical' periods), but how to study or even model this interaction has proven difficult. The hoary concept of evaluating traits according to nature versus nurture continues to persist despite repeated demonstrations that it retards, rather than advances, our understanding of biological processes. Behavioral genetics has proven the obvious, that genes influence behavior and, vice versa, that behavior influences genes. The concept of Genes X Environment (G X E) and its modern variants was viewed as an improvement on nature-nurture but has proven that, except in rare instances, it is not possible to fractionate phenotypes into these constituent elements. The entanglement inherent in terms such as nature-nurture or G X E is a Gordian knot that cannot be dissected or even split. Given that the world today is not what it was less than a century ago, yet the arbitrator (differential survival and reproduction) has stayed constant, de novo principles and practices are needed to better predict what the future holds. Put simply, the transformation that is now occurring within and between individuals as a product of global endocrine disruption is quite independent of what has been regarded as evolution by selection. This new perspective should focus on how epigenetic modifications might revise approaches to understand how the phenotype and, in particular its components, is shaped. In this review we summarize the literature in this developing area, focusing on our research on the fungicide vinclozolin. Copyright © 2014 Elsevier Ireland Ltd. All rights reserved.
TOTAL KNEE REPLACEMENT IN PATIENTS WITH BELOW-KNEE AMPUTATION
Karam, Matthew D; Willey, Michael; Shurr, Donald G
2010-01-01
Total knee replacement (TKR) is reserved for patients with severe and disabling arthritis that is non-responsive to conservative measures. Based on existing data, total knee replacement is a safe and cost-effective treatment for alleviating pain and improving physical function in patients who do not respond to conservative therapy. Despite the large variation in health status of patients and types of prosthesis implanted, total knee replacement has proven to be a relatively low risk and successful operation. Each year in the United States surgeons perform approximately 300,000 TKR.1 Likewise, lower extremity amputation is commonly performed in the United States with an annual incidence of 110,000 per year.2 Nearly 70% of all lower extremity amputations are performed as the result of chronic vascular disease, followed by trauma (22%), congenital etiology and tumor (4% each).3 Approximately 50% of all lower extremity amputations are performed secondary to complications from Diabetes Mellitus. Norvell et al. demonstrated that patients who have previously undergone transtibial amputation and ambulate with a prosthesis are more likely to develop degenerative joint disease in the con-tralateral extremity than the ipsilateral extremity.4 Further, radiographic changes consistent with osteoporosis have been demonstrated in up to 88% of limbs that have undergone transtibial amputation.8 To our knowledge, there have been only three reported cases of total knee replacement in patients with ipsilateral transtibial amputation.5,7 The purpose of the present study is to review the existing data on total knee replacement in patients who have undergone transtibial amputation. Further we present a patient with a transtibial amputation who underwent contralateral total knee replacement. PMID:21045987
NASA Technical Reports Server (NTRS)
Laub, Bernard; Grinstead, Jay; Dyakonov, Artem; Venkatapathy, Ethiraj
2011-01-01
Though arc jet testing has been the proven method employed for development testing and certification of TPS and TPS instrumentation, the operational aspects of arc jets limit testing to selected, but constant, conditions. Flight, on the other hand, produces timevarying entry conditions in which the heat flux increases, peaks, and recedes as a vehicle descends through an atmosphere. As a result, we are unable to "test as we fly." Attempts to replicate the time-dependent aerothermal environment of atmospheric entry by varying the arc jet facility operating conditions during a test have proven to be difficult, expensive, and only partially successful. A promising alternative is to rotate the test model exposed to a constant-condition arc jet flow to yield a time-varying test condition at a point on a test article (Fig. 1). The model shape and rotation rate can be engineered so that the heat flux at a point on the model replicates the predicted profile for a particular point on a flight vehicle. This simple concept will enable, for example, calibration of the TPS sensors on the Mars Science Laboratory (MSL) aeroshell for anticipated flight environments.
NASA Astrophysics Data System (ADS)
Anderson, C.
2017-12-01
California's hydroclimatic regime is characterized by extreme interannual variability including periodic, multi-year droughts and winter flooding sequences. Statewide, water years 2012-2016 were characterized by extreme drought followed by likely one of the wettest years on record in water year 2017. Similar drought-flood patterns have occurred multiple times both in the contemporary empirical record and reconstructed climate records. Both the extreme magnitude and rapid succession of these hydroclimatic periods pose difficult challenges for water managers and regulatory agencies responsible for providing instream flows to protect and recover threatened and endangered fish species. Principal among these riverine fish species are federally listed winter-run and spring-run Chinook salmon (Oncorhynchus tshawytscha), Central Valley steelhead (Oncorhynchus mykiss), and the pelagic species Delta smelt (Hypomesus transpacificus). Poor instream conditions from 2012-2016 resulted in extremely low abundance estimates and poor overall fish health, and while fish monitoring results from water year 2017 are too preliminary to draw substantive conclusions, early indicators show continued downward population trends despite the historically wet conditions. This poster evaluates California's hydroclimatic conditions over the past decade and quantifies resultant impacts of the 2012-2016 drought and the extremely wet 2017 water year to both adult escapement and juvenile production estimates in California's major inland salmon rivers over that same time span. We will also examine local, state, and federal regulatory actions both in response to the extreme hydroclimatic variability and in preparation for future drought-flood sequences.
Leveillee, Raymond J; Kelly, Emily Fell
2016-01-01
Since the development of the first flexible ureteroscope, in 1964, technological advances in image quality, flexibility, and deflection have led to the development of the first single-use digital flexible ureteroscope, LithoVue™ (Boston Scientific, Marlborough, MA). With respect to reusable fiber-optic and now digital ureteroscopes, there is an initial capital cost of several thousand dollars (USD) as well as, controversy regarding durability, the cost of repairs and the burdensome reprocessing steps of ureteroscopy. The single-use LithoVue eliminates the need for costly repairs, the occurrence of unpredictable performance, and procedural delays. Renal stones located in the lower pole of the kidney can be extremely challenging as extreme deflections of greater than 160° are difficult to maintain and are often further compromised when using stone treatment tools, such as laser fibers and baskets. This case describes an initial use of the LithoVue digital disposable ureteroscope in the effective treatment of lower pole calculi using a 365 μm holmium laser fiber. A 35-year-old female, with a medical history significant for chronic bacteriuria, and recurrent symptomatic culture proven urinary tract infections, underwent localization studies. Retrograde ureteropyelography demonstrated two calcifications adjoining, measuring a total of 1.4 cm, overlying the left renal shadow. Urine aspirated yielded clinically significant, >100,000, Escherichia coli and Streptococcus anginosus bacteriuria, which was felt to be originating from the left lower calix. This case used the newly FDA-approved LithoVue flexible disposable ureteroscope. The two stones were seen using the ureteroscope passed through an ureteral access sheath in the lower pole calix. A 365 μm holmium laser fiber was inserted into the ureteroscope and advanced toward the stones. There was no loss of deflection as the ureteroscope performed reproducibly. The laser was used for more than 4000 pulses at 15 W, producing mucoid debris and fragments. A 1.9F nitinol basket was, then, used to extract the fragments, and the patient was rendered stone free. Treatment success was confirmed by plain abdominal film obtained 1 week after stent removal. The LithoVue system single-use digital flexible ureteroscope provides an economical advantage over both reusable digital and fiber-optic ureteroscopes. The LithoVue system uses the enhanced image resolution of the digital complementary metal oxide semiconductor imager, similar to other reusable digital ureteroscopes, while maintaining the small ureteroscope size of a flexible fiber-optic ureteroscope, allowing for consistent and effective lower pole access. Deflection characteristics are maintained even when thicker laser fibers are passed through the working channel.
NASA Astrophysics Data System (ADS)
Ofir, Aviv; Dreizler, Stefan; Zechmeister, Mathias; Husser, Tim-Oliver
2014-01-01
Context. The primary goal of the Kepler mission is the measurement of the frequency of Earth-like planets around Sun-like stars. However, the confirmation of the smallest of Kepler's candidates in long periods around FGK dwarfs is extremely difficult or even beyond the limit of current radial velocity technology. Transit timing variations (TTVs) may offer the possibility for these confirmations of near-resonant multiple systems by the mutual gravitational interaction of the planets. Aims: We previously detected the second planet candidate in the KOI 1574 system. The two candidates have relatively long periods (about 114 d and 191 d) and are in 5:3 resonance. We therefore searched for TTVs in this particularly promising system. Methods: The full Kepler data was detrended with the proven SARS pipeline. The entire data allowed one to search for TTVs of the above signals, and to search for additional transit-like signals. Results: We detected strong anti-correlated TTVs of the 114 d and 191 d signals, dynamically confirming them as members of the same system. Dynamical simulations reproducing the observed TTVs allowed us to also determine the masses of the planets. We found KOI 1574.01 (hereafter Kepler-87 b) to have a radius of 13.49 ± 0.55 R⊕ and a mass of 324.2 ± 8.8 M⊕, and KOI 1574.02 (Kepler-87 c) to have a radius of 6.14 ± 0.29 R⊕ and a mass of 6.4 ± 0.8 M⊕. Both planets have low densities of 0.729 and 0.152 g cm-3, respectively, which is non-trivial for such cold and old (7-8 Gyr) planets. Specifically, Kepler-87 c is the lowest-density planet in the super-Earth mass range. Both planets are thus particularly amenable to modeling and planetary structure studies, and also present an interesting case where ground-based photometric follow-up of Kepler planets is very desirable. Finally, we also detected two more short-period super-Earth sized (<2 R⊕) planetary candidates in the system, making the relatively high multiplicity of this system notable against the general paucity of multiple systems in the presence of giant planets like Kepler-87 b.
The administrator's quest for quality.
Ross, A
1988-01-01
Times are tough and will become even tougher. Retrenchment issues will be foremost in many operational settings. Failure to understand baseline quality standards will make it extremely difficult to know where to cut and how to regroup without adversely affecting patient attitudes and service. Practice patterns are changing rapidly and the astute administrator needs to be prepared to participate freely in decisions affecting quality, service and costs.
Labor Market Changes in the Next Ten Years. Issue Paper No. 4.
ERIC Educational Resources Information Center
Barnow, Burt S.
Although projecting what the labor market will be like in 10 years is extremely difficult, it is useful to consider what is in store for the nation in terms of employment. In 1985, the civilian labor force of the United States averaged 115 million persons, with 8 million (7.2 percent) unemployed. Unemployment was much higher for young people and…
Cleft Lip and Cleft Palate--What to Know and Who Can Help
ERIC Educational Resources Information Center
Apel, Laura
2008-01-01
Craniofacial defects such as cleft lip and cleft palate are among the most common of all birth defects in the United States, with one in every 600 newborns affected. Cleft lip and/or palate can occur as an isolated condition or may be one component of an inherited disease or syndrome. Dealing with the condition is an extremely difficult and…
The Devil Is in the Details: Key Questions in the Effort To "End Welfare as We Know It."
ERIC Educational Resources Information Center
Greenberg, Mark
Noting the while there may be much support for the principle that families on welfare should have access to 2 years of education and training and then be expected to work, this paper contends that it will be extremely difficult, perhaps impossible, to design a coherent and constructive program within the probable federal budget constraints. In…
Industry Studies 2004: Biotechnology
2004-01-01
for biological agent research, development, and production are available on the open market. Since biological weapons are relatively cheap, easy to...growing concern is that non-state actors will acquire and use a biological weapon , the “poor man’s nuclear weapon .” Such action is extremely difficult...to detect and counter. International Protocols and the Need to Control Agents and Technologies - The Biological and Toxin Weapons Convention
1990-09-01
increasing 2 complexity of Air Force weapon systems makes the estimation of LCC an extremely difficult task. To accomplish this, mathematical models are...maintenance is nearly horizontal. A reduction in this rate from 2.8 to 2.6 (approx. 7%j resulted in cost savings of around 0.1% for the three lvel concept. The
JPRS Report, Soviet Union, Political Affairs
1988-10-26
Christa Wolfs novel "Patterns of Childhood." This very sensitive and timely work reflects the psychology attending the rise of fascism. We also have...incriminating evidence and extenuating circumstances? Psychologically , it is extremely difficult. There are allegations, there are sus- picions, there are...Zionism, which has for a long time been chipping away at the socialist foundation of our society, with its perfidious psychological methods." What does
2008-03-27
deportees from the United States have made the process of leaving a gang extremely difficult. A recent State Department report on youth gangs in El...gang members, especially returning deportees from the United States who are often native English speakers, have had the most difficulty finding...with the exception of Panama, have a much lower percentage of criminal deportees than the regional average of 39%. For example, criminal deportees
Sine Qua Non: Indispensable Resources for Ed Tech Professionals. Part 1: Educational Technology
ERIC Educational Resources Information Center
Conley, Kate
2004-01-01
Because the field of educational technology is so broad and dynamic, it is extremely difficult to find time to keep up with the best practices, current research, and innovative ideas. In an effort to help readers keep up their knowledge of the field and to determine some of the most interesting and useful resources to date, a large body of…
ERIC Educational Resources Information Center
Jackson, Bernedette S.
2017-01-01
Learning a second or foreign language may be a daunting task for anyone; however, learning a language that is vastly different from a person's native language can be extremely difficult. This is especially true in South Korea where English is taught and spoken as a foreign language. For Korean students, who typically study English from a young…
ERIC Educational Resources Information Center
Varea, Valeria; Underwood, Mair
2016-01-01
Research among former Physical Education (PE) school students has demonstrated how fat phobia in PE classes is oppressive and makes it extremely difficult for most students to develop positive subjectivities. This study explores how a group of pre-service Health and Physical Education (HPE) specialist teachers from an Australian university…
ERIC Educational Resources Information Center
Cervantes, Joseph M.; Mejia, Olga L.; Mena, Amalia Guerrero
2010-01-01
There has been a significant trend among families from Mexico and Central America to immigrate to the United States due to difficult living conditions, financial hardship, and the lack of opportunity. This article addresses the role of serial migration, where one family member immigrates first and then brings the rest of the family at a later…
Assessing wood quality of borer-infested red oak logs with a resonance acoustic technique
Xiping Wang; Henry E. Stelzer; Jan Wiedenbeck; Patricia K. Lebow; Robert J. Ross
2009-01-01
Large numbers of black oak (Quercus velutina Lam.) and scarlet oak (Quercus coccinea Muenchh.) trees are declining and dying in the Missouri Ozark forest as a result of oak decline. Red oak borer-infested trees produce low-grade logs that become extremely difficult to merchandize as the level of insect attack increases. The objective of this study was to investigate...
1979-05-01
and social problems, does not lend itself to a single or simple solution. This is why we must all be involved. For this reason we. believe that...of admission to decisionmaking. At times the implications of this relatively simple premise are not minor. Many people beginning community...involvement programs have found it extremely difficult to locate technical people able to translate technical reports into simple , every- day English. There
Atmosphere-fire simulation of effects of low-level jets on pyro-convective plume dynamics
Colin C. Simpson; Marwan Katurji; Michael T. Kiefer; Shiyuan Zhong; Joseph J. Charney; Warren E. Heilman; Xindi Bian
2013-01-01
Blow-up fire behaviour can be broadly defined as a rapid escalation in the intensity or forward rate of spread of a wildland fire, and is often accompanied by extreme pyro-convection associated with rapid smoke release and dispersion. Blow-up fire behaviour is difficult to predict and has been linked to firefighter fatalities, making it an important fire management...
Concurrency Attacks and Defenses
2016-10-04
Enter name(s) of person(s) responsible for writing the report, performing the research, or credited with the content of the report. The form of...Amsterdam Avenue New York, NY 10027-7003 Tel.: 212-939-7012 Fax: 212-666-0140 Email : junfeng@cs.columbia.edu 2. Research Objectives...Multithreaded programs are getting increasingly pervasive and critical. Unfortunately, they remain extremely difficult to write . This difficulty has led to
Long-Ming Huang
2000-01-01
Improper cultivation of steep mountainous areas in Taiwan contributes to serious erosion and landslides. Regular patrol, detection, and administration of these problem areas has been an extremely difficult due to the steep and dangerous terrain of many of the forested watersheds in Taiwan. A remotely piloted vehicle (RPV) has been developed for various civil and...
Atiyeh, Bishara S
2007-01-01
Hypertrophic scars, resulting from alterations in the normal processes of cutaneous wound healing, are characterized by proliferation of dermal tissue with excessive deposition of fibroblast-derived extracellular matrix proteins, especially collagen, over long periods, and by persistent inflammation and fibrosis. Hypertrophic scars are among the most common and frustrating problems after injury. As current aesthetic surgical techniques become more standardized and results more predictable, a fine scar may be the demarcating line between acceptable and unacceptable aesthetic results. However, hypertrophic scars remain notoriously difficult to eradicate because of the high recurrence rates and the incidence of side effects associated with available treatment methods. This review explores the various treatment methods for hypertrophic scarring described in the literature including evidence-based therapies, standard practices, and emerging methods, attempting to distinguish those with clearly proven efficiency from anecdotal reports about therapies of doubtful benefits while trying to differentiate between prophylactic measures and actual treatment methods. Unfortunately, the distinction between hypertrophic scar treatments and keloid treatments is not obvious in most reports, making it difficult to assess the efficacy of hypertrophic scar treatment.
Successful Aging: Advancing the Science of Physical Independence in Older Adults
Anton, Stephen D.; Woods, Adam J.; Ashizawa, Tetso; Barb, Diana; Buford, Thomas W.; Carter, Christy S.; Clark, David J.; Cohen, Ronald A.; Corbett, Duane B.; Cruz-Almeida, Yenisel; Dotson, Vonetta; Ebner, Natalie; Efron, Philip A.; Fillingim, Roger B.; Foster, Thomas C.; Gundermann, David M.; Joseph, Anna-Maria; Karabetian, Christy; Leeuwenburgh, Christiaan; Manini, Todd M.; Marsiske, Michael; Mankowski, Robert T.; Mutchie, Heather L.; Perri, Michael G.; Ranka, Sanjay; Rashidi, Parisa; Sandesara, Bhanuprasad; Scarpace, Philip J.; Sibille, Kimberly T.; Solberg, Laurence M.; Someya, Shinichi; Uphold, Connie; Wohlgemuth, Stephanie; Wu, Samuel Shangwu; Pahor, Marco
2015-01-01
The concept of ‘Successful Aging’ has long intrigued the scientific community. Despite this long-standing interest, a consensus definition has proven to be a difficult task, due to the inherent challenge involved in defining such a complex, multi-dimensional phenomenon. The lack of a clear set of defining characteristics for the construct of successful aging has made comparison of findings across studies difficult and has limited advances in aging research. The domain in which consensus on markers of successful aging is furthest developed is the domain of physical functioning. For example, walking speed appears to be an excellent surrogate marker of overall health and predicts the maintenance of physical independence, a cornerstone of successful aging. The purpose of the present article is to provide an overview and discussion of specific health conditions, behavioral factors, and biological mechanisms that mark declining mobility and physical function and promising interventions to counter these effects. With life expectancy continuing to increase in the United States and developed countries throughout the world, there is an increasing public health focus on the maintenance of physical independence among all older adults. PMID:26462882
Reproducibility and Knowledge Capture Architecture for the NASA Earth Exchange (NEX)
NASA Astrophysics Data System (ADS)
Votava, P.; Michaelis, A.; Nemani, R. R.
2015-12-01
NASA Earth Exchange (NEX) is a data, supercomputing and knowledge collaboratory that houses NASA satellite, climate and ancillary data where a focused community can come together to address large-scale challenges in Earth sciences. As NEX has been growing into a platform for analysis, experiments and production of data on the order of petabytes in volume, it has been increasingly important to enable users to easily retrace their steps, identify what datasets were produced by which process or chain of processes, and give them ability to readily reproduce their results. This can be a tedious and difficult task even for a small project, but is almost impossible on large processing pipelines. For example, the NEX Landsat pipeline is deployed to process hundreds of thousands of Landsat scenes in a non-linear production workflow with many-to-many mappings of files between 40 separate processing stages where over 100 million processes get executed. At this scale it is almost impossible to easily examine the entire provenance of each file, let alone easily reproduce it. We have developed an initial solution for the NEX system - a transparent knowledge capture and reproducibility architecture that does not require any special code instrumentation and other actions on user's part. Users can automatically capture their work through a transparent provenance tracking system and the information can subsequently be queried and/or converted into workflows. The provenance information is streamed to a MongoDB document store and a subset is converted to an RDF format and inserted into our triple-store. The triple-store already contains semantic information about other aspects of the NEX system and adding provenance enhances the ability to relate workflows and data to users, locations, projects and other NEX concepts that can be queried in a standard way. The provenance system has the ability to track data throughout NEX and across number of executions and can recreate and re-execute the entire history and reproduce the results. The information can also be used to automatically create individual workflow components and full workflows that can be visually examined, modified, executed and extended by researchers. This provides a key component for accelerating research through knowledge capture and scientific reproducibility on NEX.
Between land and sea: divergent data stewardship practices in deep-sea biosphere research
NASA Astrophysics Data System (ADS)
Cummings, R.; Darch, P.
2013-12-01
Data in deep-sea biosphere research often live a double life. While the original data generated on IODP expeditions are highly structured, professionally curated, and widely shared, the downstream data practices of deep-sea biosphere laboratories are far more localized and ad hoc. These divergent data practices make it difficult to track the provenance of datasets from the cruise ships to the laboratory or to integrate IODP data with laboratory data. An in-depth study of the divergent data practices in deep-sea biosphere research allows us to: - Better understand the social and technical forces that shape data stewardship throughout the data lifecycle; - Develop policy, infrastructure, and best practices to improve data stewardship in small labs; - Track provenance of datasets from IODP cruises to labs and publications; - Create linkages between laboratory findings, cruise data, and IODP samples. In this paper, we present findings from the first year of a case study of the Center for Dark Energy Biosphere Investigations (C-DEBI), an NSF Science and Technology Center that studies life beneath the seafloor. Our methods include observation in laboratories, interviews, document analysis, and participation in scientific meetings. Our research uncovers the data stewardship norms of geologists, biologists, chemists, and hydrologists conducting multi-disciplinary research. Our research team found that data stewardship on cruises is a clearly defined task performed by an IODP curator, while downstream it is a distributed task that develops in response to local need and to the extent necessary for the immediate research team. IODP data are expensive to collect and challenging to obtain, often costing $50,000/day and requiring researchers to work twelve hours a day onboard the ships. To maximize this research investment, a highly trained IODP data curator controls data stewardship on the cruise and applies best practices such as standardized formats, proper labeling, and centralized storage. In the laboratory, a scientist is his or her own curator. In contrast to the IODP research parties, laboratory research teams analyze diverse datasets, share them internally, implement ad hoc data management practices, optimize methods for their specific research questions, and release data on request through personal transactions. We discovered that while these workflows help small research teams retain flexibility and local control - crucial in exploratory deep-sea biosphere research - they also hinder data interoperability, discoverability, and consistency of methods from one research team to the next. Additional consequences of this contrast between IODP and lab practices are that it is difficult to track the provenance of data and to create linkages between laboratory findings, cruise data, and archived IODP samples. The ability to track provenance would add value to datasets and provide a clearer picture of the decisions made throughout the data lifecycle. Better linkages between the original data, laboratory data, and samples would allow secondary researchers to locate IODP data that may be useful to their research after laboratory findings are published. Our case study is funded by the Sloan Foundation and NSF.
K-wire assisted split-thickness skin graft harvesting from the anterior trunk.
Yontar, Yalcin; Coruh, Atilla; Severcan, Mehmet
2016-02-01
Split thickness skin graft (STSG) harvesting from the anterior chest and abdominal wall skin is quite a difficult process. The main reason for the difficulty to perform this process is the unsuitable anatomic characteristics of the anterior trunk, such as irregular wavy-like surface over the ribs and lax abdominal wall skin resulting in collapse due to lack of adequate underneath supporting structures when a downward force is applied by the skin graft dermatome. Lower extremity and especially the thigh are generally chosen as the donor site where the STSGs are easily harvested from. However, extensive lower extremity burns, with or without other region burns, preclude harvesting auto STSGs from this invaluable anatomic site. We harvested K-wire assisted STSGs from the anterior chest and abdominal wall skin of 7 patients with lower extremity burns and also a patient that sustained motor vehicle collision. We encountered no problems in any of our patients both intra and postoperatively by using K-wire assisted STSG harvesting. All of the STSGs donor sites healed uneventfully without complications. In our opinion, K-wire assisted STSG harvesting must always be in the tool-box of any surgeon who deals with extensive burns with or without lower extremity burns and extensive traumas of lower extremities. Copyright © 2015 Elsevier Ltd and ISBI. All rights reserved.
Bioengineered Plants Can Be a Useful Source of Omega-3 Fatty Acids
Lyu, Shan-Wu
2017-01-01
Omega-3 fatty acids have proven to be very essential for human health due to their multiple health benefits. These essential fatty acids (EFAs) need to be uptaken through diet because they are unable to be produced by the human body. These are important for skin and hair growth as well as for proper visual, neural, and reproductive functions of the body. These fatty acids are proven to be extremely vital for normal tissue development during pregnancy and infancy. Omega-3 fatty acids can be obtained mainly from two dietary sources: marine and plant oils. Eicosapentaenoic acid (EPA; C20:5 n-3) and docosahexaenoic acid (DHA; C22:6 n-3) are the primary marine-derived omega-3 fatty acids. Marine fishes are high in omega-3 fatty acids, yet high consumption of those fishes will cause a shortage of fish stocks existing naturally in the oceans. An alternative source to achieve the recommended daily intake of EFAs is the demand of today. In this review article, an attempt has, therefore, been made to discuss the importance of omega-3 fatty acids and the recent developments in order to produce these fatty acids by the genetic modifications of the plants. PMID:28316988
Bioengineered Plants Can Be a Useful Source of Omega-3 Fatty Acids.
Amjad Khan, Waleed; Chun-Mei, Hu; Khan, Nadeem; Iqbal, Amjad; Lyu, Shan-Wu; Shah, Farooq
2017-01-01
Omega-3 fatty acids have proven to be very essential for human health due to their multiple health benefits. These essential fatty acids (EFAs) need to be uptaken through diet because they are unable to be produced by the human body. These are important for skin and hair growth as well as for proper visual, neural, and reproductive functions of the body. These fatty acids are proven to be extremely vital for normal tissue development during pregnancy and infancy. Omega-3 fatty acids can be obtained mainly from two dietary sources: marine and plant oils. Eicosapentaenoic acid (EPA; C20:5 n-3) and docosahexaenoic acid (DHA; C22:6 n-3) are the primary marine-derived omega-3 fatty acids. Marine fishes are high in omega-3 fatty acids, yet high consumption of those fishes will cause a shortage of fish stocks existing naturally in the oceans. An alternative source to achieve the recommended daily intake of EFAs is the demand of today. In this review article, an attempt has, therefore, been made to discuss the importance of omega-3 fatty acids and the recent developments in order to produce these fatty acids by the genetic modifications of the plants.
Health care-associated infections in the neonatal intensive care unit.
Brady, Michael T
2005-06-01
Neonates represent a unique and highly vulnerable patient population. Advances in medical technology that have occurred over the last few decades have improved the survival and quality of life for neonates, particularly those infants born with extreme prematurity or with congenital defects. Although immunologic immaturity and altered cutaneous barriers play some role in the vulnerability of neonates to nosocomial infections, clearly, therapeutic interventions that have proven to be lifesaving for these fragile infants also appear to be associated with the majority of infectious complications resulting in neonatal morbidity and mortality. Rates of infections in neonatal intensive care units (NICUs) have varied from 6% to 40% of neonatal patients, with the highest rates in those facilities having larger proportions of very low-birth-weight infants (birthweight < or =1000 grams) or neonates requiring surgery. Efforts to protect the vulnerable NICU infants include the following: (1) optimal infection control practices, especially good hand hygiene and good nursery design; (2) prudent use of invasive interventions with particular attention to early removal of invasive devices after they are no longer essential; and (3) judicious use of antimicrobial agents, with an emphasis on targeted (narrow spectrum) rather than broad-spectrum antibiotics and appropriate indications (proven or suspected bacterial infections).
Sharma, Rajeev; Luthra, Pallavi; Karad, Amit; Dhariwal, A C; Ichhpujani, R L; Lal, Shiv
2010-06-01
Information Communication Technology (ICT) has proven to be a strong public health tool. Keeping the future need of country and building National Disease Surveillance System, Integrated Disease Surveillance Project (IDSP) was launched by Hon'ble Union Minister of Health & Family Welfare in November 2004. It is a decentralized, State based surveillance program in the country. It is intended to detect early warning signals of impending outbreaks and help initiate an effective response in a timely manner. One of the major components of the project is the - use of Information Technology for collection, collation, compilation, analysis and dissemination of data besides distance education and video conferencing. A network of 800 sites across India has been established through Satellite, Broadband and High end Video conferencing equipments. The network is managed by a team of data managers and data entry operators at all state surveillance units and district surveillance units respectively. The network was proven to be extremely useful to respond to the current influenza A H1N1 pandemic. It is proposed to extend the network to cover private sector and provide convergence with other National Health Programs.
Constraints on Fluctuations in Sparsely Characterized Biological Systems.
Hilfinger, Andreas; Norman, Thomas M; Vinnicombe, Glenn; Paulsson, Johan
2016-02-05
Biochemical processes are inherently stochastic, creating molecular fluctuations in otherwise identical cells. Such "noise" is widespread but has proven difficult to analyze because most systems are sparsely characterized at the single cell level and because nonlinear stochastic models are analytically intractable. Here, we exactly relate average abundances, lifetimes, step sizes, and covariances for any pair of components in complex stochastic reaction systems even when the dynamics of other components are left unspecified. Using basic mathematical inequalities, we then establish bounds for whole classes of systems. These bounds highlight fundamental trade-offs that show how efficient assembly processes must invariably exhibit large fluctuations in subunit levels and how eliminating fluctuations in one cellular component requires creating heterogeneity in another.
Optimizing Global Coronal Magnetic Field Models Using Image-Based Constraints
NASA Technical Reports Server (NTRS)
Jones-Mecholsky, Shaela I.; Davila, Joseph M.; Uritskiy, Vadim
2016-01-01
The coronal magnetic field directly or indirectly affects a majority of the phenomena studied in the heliosphere. It provides energy for coronal heating, controls the release of coronal mass ejections, and drives heliospheric and magnetospheric activity, yet the coronal magnetic field itself has proven difficult to measure. This difficulty has prompted a decades-long effort to develop accurate, timely, models of the field, an effort that continues today. We have developed a method for improving global coronal magnetic field models by incorporating the type of morphological constraints that could be derived from coronal images. Here we report promising initial tests of this approach on two theoretical problems, and discuss opportunities for application.
Analysis of a membrane-based condesate recovery heat exchanger (CRX)
NASA Technical Reports Server (NTRS)
Newbold, D.D.
1993-01-01
The development of a temperature and humidity control system that can remove heat and recover water vapor is key to the development of an Environmental Control and Life Support System (ECLSS). Large quantities of water vapor must be removed from air, and this operation has proven difficult in the absense of gravity. This paper presents the modeling results from a program to develop a novel membrane-based heat exchanger known as the condensate recovery heat exchanger (CRX). This device cools and dehumidifies humid air and simultaneously recovers water-vapor condensate. In this paper, the CRX is described and the results of an analysis of the heat- and mass-transfer characteristics of the device are given.
Neural Cross-Frequency Coupling: Connecting Architectures, Mechanisms, and Functions.
Hyafil, Alexandre; Giraud, Anne-Lise; Fontolan, Lorenzo; Gutkin, Boris
2015-11-01
Neural oscillations are ubiquitously observed in the mammalian brain, but it has proven difficult to tie oscillatory patterns to specific cognitive operations. Notably, the coupling between neural oscillations at different timescales has recently received much attention, both from experimentalists and theoreticians. We review the mechanisms underlying various forms of this cross-frequency coupling. We show that different types of neural oscillators and cross-frequency interactions yield distinct signatures in neural dynamics. Finally, we associate these mechanisms with several putative functions of cross-frequency coupling, including neural representations of multiple environmental items, communication over distant areas, internal clocking of neural processes, and modulation of neural processing based on temporal predictions. Copyright © 2015 Elsevier Ltd. All rights reserved.
From 3D to 2D: A Review of the Molecular Imprinting of Proteins
Turner, Nicholas W.; Jeans, Christopher W.; Brain, Keith R.; Allender, Christopher J.; Hlady, Vladimir; Britt, David W.
2008-01-01
Molecular imprinting is a generic technology that allows for the introduction of sites of specific molecular affinity into otherwise homogeneous polymeric matrices. Commonly this technique has been shown to be effective when targeting small molecules of molecular weight <1500, while extending the technique to larger molecules such as proteins has proven difficult. A number of key inherent problems in protein imprinting have been identified, including permanent entrapment, poor mass transfer, denaturation, and heterogeneity in binding pocket affinity, which have been addressed using a variety of approaches. This review focuses on protein imprinting in its various forms, ranging from conventional bulk techniques to novel thin film and monolayer surface imprinting approaches. PMID:17137293
Pickering, Janessa; Richmond, Peter C.; Kirkham, Lea-Ann S.
2014-01-01
Non-typeable Haemophilus influenzae (NTHi) and Haemophilus haemolyticus are closely related bacteria that reside in the upper respiratory tract. NTHi is associated with respiratory tract infections that frequently result in antibiotic prescription whilst H. haemolyticus is rarely associated with disease. NTHi and H. haemolyticus can be indistinguishable by traditional culture methods and molecular differentiation has proven difficult. This current review chronologically summarizes the molecular approaches that have been developed for differentiation of NTHi from H. haemolyticus, highlighting the advantages and disadvantages of each target and/or technique. We also provide suggestions for the development of new tools that would be suitable for clinical and research laboratories. PMID:25520712
Urban Sprawl, Smart Growth, and Deliberative Democracy
2010-01-01
Urban sprawl is an increasingly common feature of the built environment in the United States and other industrialized nations. Although there is considerable evidence that urban sprawl has adverse affects on public health and the environment, policy frameworks designed to combat sprawl—such as smart growth—have proven to be controversial, making implementation difficult. Smart growth has generated considerable controversy because stakeholders affected by urban planning policies have conflicting interests and divergent moral and political viewpoints. In some of these situations, deliberative democracy—an approach to resolving controversial public-policy questions that emphasizes open, deliberative debate among the affected parties as an alternative to voting—would be a fair and effective way to resolve urban-planning issues. PMID:20724685
Chu, Yanjie; Oum, Yoon Hyeun; Carrico, Isaac S
2016-01-01
As a result of their ability to integrate into the genome of both dividing and non-dividing cells, lentiviruses have emerged as a promising vector for gene delivery. Targeted gene transduction of specific cells and tissues by lentiviral vectors has been a major goal, which has proven difficult to achieve. We report a novel targeting protocol that relies on the chemoselective attachment of cancer specific ligands to unnatural glycans on lentiviral surfaces. This strategy exhibits minimal perturbation on virus physiology and demonstrates remarkable flexibility. It allows for targeting but can be more broadly useful with applications such as vector purification and immunomodulation. Copyright © 2015 Elsevier Inc. All rights reserved.
Constraints on Fluctuations in Sparsely Characterized Biological Systems
NASA Astrophysics Data System (ADS)
Hilfinger, Andreas; Norman, Thomas M.; Vinnicombe, Glenn; Paulsson, Johan
2016-02-01
Biochemical processes are inherently stochastic, creating molecular fluctuations in otherwise identical cells. Such "noise" is widespread but has proven difficult to analyze because most systems are sparsely characterized at the single cell level and because nonlinear stochastic models are analytically intractable. Here, we exactly relate average abundances, lifetimes, step sizes, and covariances for any pair of components in complex stochastic reaction systems even when the dynamics of other components are left unspecified. Using basic mathematical inequalities, we then establish bounds for whole classes of systems. These bounds highlight fundamental trade-offs that show how efficient assembly processes must invariably exhibit large fluctuations in subunit levels and how eliminating fluctuations in one cellular component requires creating heterogeneity in another.
From 3D to 2D: a review of the molecular imprinting of proteins.
Turner, Nicholas W; Jeans, Christopher W; Brain, Keith R; Allender, Christopher J; Hlady, Vladimir; Britt, David W
2006-01-01
Molecular imprinting is a generic technology that allows for the introduction of sites of specific molecular affinity into otherwise homogeneous polymeric matrices. Commonly this technique has been shown to be effective when targeting small molecules of molecular weight <1500, while extending the technique to larger molecules such as proteins has proven difficult. A number of key inherent problems in protein imprinting have been identified, including permanent entrapment, poor mass transfer, denaturation, and heterogeneity in binding pocket affinity, which have been addressed using a variety of approaches. This review focuses on protein imprinting in its various forms, ranging from conventional bulk techniques to novel thin film and monolayer surface imprinting approaches.
Urban sprawl, smart growth, and deliberative democracy.
Resnik, David B
2010-10-01
Urban sprawl is an increasingly common feature of the built environment in the United States and other industrialized nations. Although there is considerable evidence that urban sprawl has adverse affects on public health and the environment, policy frameworks designed to combat sprawl-such as smart growth-have proven to be controversial, making implementation difficult. Smart growth has generated considerable controversy because stakeholders affected by urban planning policies have conflicting interests and divergent moral and political viewpoints. In some of these situations, deliberative democracy-an approach to resolving controversial public-policy questions that emphasizes open, deliberative debate among the affected parties as an alternative to voting-would be a fair and effective way to resolve urban-planning issues.
OPTIMIZING GLOBAL CORONAL MAGNETIC FIELD MODELS USING IMAGE-BASED CONSTRAINTS
DOE Office of Scientific and Technical Information (OSTI.GOV)
Jones, Shaela I.; Davila, Joseph M.; Uritsky, Vadim, E-mail: shaela.i.jonesmecholsky@nasa.gov
The coronal magnetic field directly or indirectly affects a majority of the phenomena studied in the heliosphere. It provides energy for coronal heating, controls the release of coronal mass ejections, and drives heliospheric and magnetospheric activity, yet the coronal magnetic field itself has proven difficult to measure. This difficulty has prompted a decades-long effort to develop accurate, timely, models of the field—an effort that continues today. We have developed a method for improving global coronal magnetic field models by incorporating the type of morphological constraints that could be derived from coronal images. Here we report promising initial tests of thismore » approach on two theoretical problems, and discuss opportunities for application.« less
Laminar Flow Control Leading Edge Systems in Simulated Airline Service
NASA Technical Reports Server (NTRS)
Wagner, R. D.; Maddalon, D. V.; Fisher, D. F.
1988-01-01
Achieving laminar flow on the wings of a commercial transport involves difficult problems associated with the wing leading edge. The NASA Leading Edge Flight Test Program has made major progress toward the solution of these problems. The effectiveness and practicality of candidate laminar flow leading edge systems were proven under representative airline service conditions. This was accomplished in a series of simulated airline service flights by modifying a JetStar aircraft with laminar flow leading edge systems and operating it out of three commercial airports in the United States. The aircraft was operated as an airliner would under actual air traffic conditions, in bad weather, and in insect infested environments.
[Extemporaneous magistral formulas for the topical treatment of pruritus : Proven and new options].
Staubach, P; Weisshaar, E
2016-08-01
The treatment of pruritus, primarily chronic pruritus, is often difficult and must be treated simultaneously with the cause of pruritus and the individual demands of the skin. Due to the chronicity, a combination of systemic therapies, different active ingredients and basic formulas must be used in local therapies and adjusted during the course of the treatment. There are still therapeutic gaps, which can be closed by the use of extemporaneous preparations. Magistral formulas, which are already checked for plausibility, should be preferred over individual prescriptions. In the following, different therapeutic options in daily practice by using extemporaneous formulas from the NRF (New German Pharmacopoeia for compounded medications) are presented.
Lecina-Diaz, Judit; Alvarez, Albert; Retana, Javier
2014-01-01
Crown fires associated with extreme fire severity are extremely difficult to control. We have assessed fire severity using differenced Normalized Burn Ratio (dNBR) from Landsat imagery in 15 historical wildfires of Pinus halepensis Mill. We have considered a wide range of innovative topographic, fuel and fire behavior variables with the purposes of (1) determining the variables that influence fire severity patterns among fires (considering the 15 wildfires together) and (2) ascertaining whether different variables affect extreme fire severity within the three fire types (topographic, convective and wind-driven fires). The among-fires analysis showed that fires in less arid climates and with steeper slopes had more extreme severity. In less arid conditions there was more crown fuel accumulation and closer forest structures, promoting high vertical and horizontal fuel continuity and extreme fire severity. The analyses carried out for each fire separately (within fires) showed more extreme fire severity in areas in northern aspects, with steeper slopes, with high crown biomass and in climates with more water availability. In northern aspects solar radiation was lower and fuels had less water limitation to growth which, combined with steeper slopes, produced more extreme severity. In topographic fires there was more extreme severity in northern aspects with steeper slopes and in areas with more water availability and high crown biomass; in convection-dominated fires there was also more extreme fire severity in northern aspects with high biomass; while in wind-driven fires there was only a slight interaction between biomass and water availability. This latter pattern could be related to the fact that wind-driven fires spread with high wind speed, which could have minimized the effect of other variables. In the future, and as a consequence of climate change, new zones with high crown biomass accumulated in non-common drought areas will be available to burn as extreme severity wildfires. PMID:24465492