Choosing the Most Effective Pattern Classification Model under Learning-Time Constraint.

PubMed

Saito, Priscila T M; Nakamura, Rodrigo Y M; Amorim, Willian P; Papa, João P; de Rezende, Pedro J; Falcão, Alexandre X

2015-01-01

Nowadays, large datasets are common and demand faster and more effective pattern analysis techniques. However, methodologies to compare classifiers usually do not take into account the learning-time constraints required by applications. This work presents a methodology to compare classifiers with respect to their ability to learn from classification errors on a large learning set, within a given time limit. Faster techniques may acquire more training samples, but only when they are more effective will they achieve higher performance on unseen testing sets. We demonstrate this result using several techniques, multiple datasets, and typical learning-time limits required by applications.

Recommendations on the use of satellite remote-sensing data for urban air quality.

PubMed

Engel-Cox, Jill A; Hoff, Raymond M; Haymet, A D J

2004-11-01

In the last 5 yr, the capabilities of earth-observing satellites and the technological tools to share and use satellite data have advanced sufficiently to consider using satellite imagery in conjunction with ground-based data for urban-scale air quality monitoring. Satellite data can add synoptic and geospatial information to ground-based air quality data and modeling. An assessment of the integrated use of ground-based and satellite data for air quality monitoring, including several short case studies, was conducted. Findings identified current U.S. satellites with potential for air quality applications, with others available internationally and several more to be launched within the next 5 yr; several of these sensors are described in this paper as illustrations. However, use of these data for air quality applications has been hindered by historical lack of collaboration between air quality and satellite scientists, difficulty accessing and understanding new data, limited resources and agency priorities to develop new techniques, ill-defined needs, and poor understanding of the potential and limitations of the data. Specialization in organizations and funding sources has limited the resources for cross-disciplinary projects. To successfully use these new data sets requires increased collaboration between organizations, streamlined access to data, and resources for project implementation.

Wavelet library for constrained devices

NASA Astrophysics Data System (ADS)

Ehlers, Johan Hendrik; Jassim, Sabah A.

2007-04-01

The wavelet transform is a powerful tool for image and video processing, useful in a range of applications. This paper is concerned with the efficiency of a certain fast-wavelet-transform (FWT) implementation and several wavelet filters, more suitable for constrained devices. Such constraints are typically found on mobile (cell) phones or personal digital assistants (PDA). These constraints can be a combination of; limited memory, slow floating point operations (compared to integer operations, most often as a result of no hardware support) and limited local storage. Yet these devices are burdened with demanding tasks such as processing a live video or audio signal through on-board capturing sensors. In this paper we present a new wavelet software library, HeatWave, that can be used efficiently for image/video processing/analysis tasks on mobile phones and PDA's. We will demonstrate that HeatWave is suitable for realtime applications with fine control and range to suit transform demands. We shall present experimental results to substantiate these claims. Finally this library is intended to be of real use and applied, hence we considered several well known and common embedded operating system platform differences; such as a lack of common routines or functions, stack limitations, etc. This makes HeatWave suitable for a range of applications and research projects.

Single-cell analysis of the transcriptome and its application in the characterization of stem cells and early embryos.

PubMed

Liu, Na; Liu, Lin; Pan, Xinghua

2014-07-01

Cellular heterogeneity within a cell population is a common phenomenon in multicellular organisms, tissues, cultured cells, and even FACS-sorted subpopulations. Important information may be masked if the cells are studied as a mass. Transcriptome profiling is a parameter that has been intensively studied, and relatively easier to address than protein composition. To understand the basis and importance of heterogeneity and stochastic aspects of the cell function and its mechanisms, it is essential to examine transcriptomes of a panel of single cells. High-throughput technologies, starting from microarrays and now RNA-seq, provide a full view of the expression of transcriptomes but are limited by the amount of RNA for analysis. Recently, several new approaches for amplification and sequencing the transcriptome of single cells or a limited low number of cells have been developed and applied. In this review, we summarize these major strategies, such as PCR-based methods, IVT-based methods, phi29-DNA polymerase-based methods, and several other methods, including their principles, characteristics, advantages, and limitations, with representative applications in cancer stem cells, early development, and embryonic stem cells. The prospects for development of future technology and application of transcriptome analysis in a single cell are also discussed.

Cognitive Decline in Down Syndrome: A Validity/Reliability Study of the Test for Severe Impairment.

ERIC Educational Resources Information Center

Cosgrave, Mary P.; McCarron, Mary; Anderson, Mary; Tyrrell, Janette; Gill, Michael; Lawlor, Brian A.

1998-01-01

The utility of the Test for Severe Impairment was studied with 60 older persons who had Down Syndrome. Construct validity, test-retest reliability, and interrater reliability were established for the full study group and for subgroups based on degree of mental retardation and dementia status. Some possible applications and limitations of the test…

Modeling Philosophies and Applications

EPA Pesticide Factsheets

All models begin with a framework and a set of assumptions and limitations that go along with that framework. In terms of fracing and RA, there are several places where models and parameters must be chosen to complete hazard identification.

Potential Space Applications for Body-Centric Wireless and E-Textile Antennas

NASA Technical Reports Server (NTRS)

Kennedy, Timothy F.; Fink, Patrick W.; Chu, Andrew W.; Studor, George F.

2007-01-01

Space environment benefits of body-centric wireless communications are numerous, particularly in the context of long duration Lunar and Martian outposts that are in planning stages at several space agencies around the world. Since crew time for such missions is a scarce commodity, seamless integration of body-centric wireless from various sources is paramount. Sources include traditional data, such as audio, video, tracking, and biotelemetry. Newer data sources include positioning, orientation, and status of handheld tools and devices, as well as management and status of on-body inventories. In addition to offering lighter weight and flexibility, performance benefits of e-textile antennas are anticipated due to advantageous use of the body s surface area. In creating e-textile antennas and RF devices, researchers are faced with the challenge of transferring conventional and novel designs to textiles. Lack of impedance control, limited conductivity, and the inability to automatically create intricate designs are examples of limitations frequently attributed to e-textiles. Reliable interfaces between e-textiles and conventional hardware also represent significant challenges. Addressing these limitations is critical to the continued development and acceptance of fabric-based circuits for body-centric wireless applications. Here we present several examples of e-textile antennas and RF devices, created using a NASA-developed process, that overcome several of these limitations. The design and performance of an equiangular spiral, miniaturized spiral-loaded slot antenna, and a hybrid coupler are considered, with the e-textile devices showing comparable performance to like designs using conventional materials.

Pulsed CO2 characterization for lidar use

NASA Technical Reports Server (NTRS)

Jaenisch, Holger M.

1992-01-01

An account is given of a scaled functional testbed laser for space-qualified coherent-detection lidar applications which employs a CO2 laser. This laser has undergone modification and characterization for inherent performance capabilities as a model of coherent detection. While characterization results show good overall performance that is in agreement with theoretical predictions, frequency-stability and pulse-length limitations severely limit the laser's use in coherent detection.

A Nanocoaxial-Based Electrochemical Sensor for the Detection of Cholera Toxin

NASA Astrophysics Data System (ADS)

Archibald, Michelle M.; Rizal, Binod; Connolly, Timothy; Burns, Michael J.; Naughton, Michael J.; Chiles, Thomas C.

2015-03-01

Sensitive, real-time detection of biomarkers is of critical importance for rapid and accurate diagnosis of disease for point of care (POC) technologies. Current methods do not allow for POC applications due to several limitations, including sophisticated instrumentation, high reagent consumption, limited multiplexing capability, and cost. Here, we report a nanocoaxial-based electrochemical sensor for the detection of bacterial toxins using an electrochemical enzyme-linked immunosorbent assay (ELISA) and differential pulse voltammetry (DPV). Proof-of-concept was demonstrated for the detection of cholera toxin (CT). The linear dynamic range of detection was 10 ng/ml - 1 μg/ml, and the limit of detection (LOD) was found to be 2 ng/ml. This level of sensitivity is comparable to the standard optical ELISA used widely in clinical applications. In addition to matching the detection profile of the standard ELISA, the nanocoaxial array provides a simple electrochemical readout and a miniaturized platform with multiplexing capabilities for the simultaneous detection of multiple biomarkers, giving the nanocoax a desirable advantage over the standard method towards POC applications. Sensitive, real-time detection of biomarkers is of critical importance for rapid and accurate diagnosis of disease for point of care (POC) technologies. Current methods do not allow for POC applications due to several limitations, including sophisticated instrumentation, high reagent consumption, limited multiplexing capability, and cost. Here, we report a nanocoaxial-based electrochemical sensor for the detection of bacterial toxins using an electrochemical enzyme-linked immunosorbent assay (ELISA) and differential pulse voltammetry (DPV). Proof-of-concept was demonstrated for the detection of cholera toxin (CT). The linear dynamic range of detection was 10 ng/ml - 1 μg/ml, and the limit of detection (LOD) was found to be 2 ng/ml. This level of sensitivity is comparable to the standard optical ELISA used widely in clinical applications. In addition to matching the detection profile of the standard ELISA, the nanocoaxial array provides a simple electrochemical readout and a miniaturized platform with multiplexing capabilities for the simultaneous detection of multiple biomarkers, giving the nanocoax a desirable advantage over the standard method towards POC applications. This work was supported by the National Institutes of Health (National Cancer Institute award No. CA137681 and National Institute of Allergy and Infectious Diseases Award No. AI100216).

Spatially selective assembly of quantum dot light emitters in an LED using engineered peptides.

PubMed

Demir, Hilmi Volkan; Seker, Urartu Ozgur Safak; Zengin, Gulis; Mutlugun, Evren; Sari, Emre; Tamerler, Candan; Sarikaya, Mehmet

2011-04-26

Semiconductor nanocrystal quantum dots are utilized in numerous applications in nano- and biotechnology. In device applications, where several different material components are involved, quantum dots typically need to be assembled at explicit locations for enhanced functionality. Conventional approaches cannot meet these requirements where assembly of nanocrystals is usually material-nonspecific, thereby limiting the control of their spatial distribution. Here we demonstrate directed self-assembly of quantum dot emitters at material-specific locations in a color-conversion LED containing several material components including a metal, a dielectric, and a semiconductor. We achieve a spatially selective immobilization of quantum dot emitters by using the unique material selectivity characteristics provided by the engineered solid-binding peptides as smart linkers. Peptide-decorated quantum dots exhibited several orders of magnitude higher photoluminescence compared to the control groups, thus, potentially opening up novel ways to advance these photonic platforms in applications ranging from chemical to biodetection.

Potential applications of immunoassays in studies of flatfish recruitment

NASA Astrophysics Data System (ADS)

Feller, Robert J.

The fisheries recruitment-stock problem, a lack of correlation between measures of reproductive output of the parent stock and recruitment to the fishery, has several potential biotic and abiotic causes. Immunoassays may be useful in examining several aspects of this and several other problems in flatfish ecology: stock identification, parasitism and disease, and trophic interactions. Given stage-specific antisera capable of recognozing antigenic moieties of, for instance, eggs, larvae, or newly-settled juveniles, it is possible to screen stomach contents of many putative predators ( e.g., shrimp or crabs) rapidly for the presence and amounts of platfish prey. This trophic application of immunological methods has great promise for measuring loss of potential recruits to predation. All immunoassays are limited by the quality of antisera used and the researcher's ability to interpret quantitative data in an ecologically meaningful way. Key references for applications of immunoassays in fish-related questions are provided with recommendations for their utilization.

Hydrologic Landscape Characterization for the Pacific Northwest, USA

EPA Science Inventory

Hydrologic classification can help address some of the challenges facing catchment hydrology. Wigington et al. (2013) developed a hydrologic landscape (HL) approach to classification that was applied to the state of Oregon. Several characteristics limited its applicability outs...

Recent applications of hard x-ray photoelectron spectroscopy

DOE PAGES

Weiland, Conan; Rumaiz, Abdul K.; Pianetta, Piero; ...

2016-05-05

Recent applications of hard x-ray photoelectron spectroscopy (HAXPES) demonstrate its many capabilities in addition to several of its limitations. Examples are given, including measurement of buried interfaces and materials under in-situ or in-operando conditions, as well as measurements under x-ray standing-wave and resonant excitation. We also present physical considerations that differentiate HAXPES from photoemission measurements utilizing soft and ultraviolet x rays.

2.4 Micron Cutoff AlGaAsSb/InGaAsSb Phototransistors for Shortwave IR Applications

NASA Technical Reports Server (NTRS)

Refaat, Tamer F.; Abedin, Nurul; Sulima, Oleg V.; Swaminathan, Krishna; Ismail, Syed; Singh, Upendra N.

2006-01-01

Shortwave infrared detectors are critical for several applications including remote sensing and optical communications. Several detectors are commercially available for this wavelength range, but they lack sufficient gain, which limits their detectivity. The characterization results of an AlGaAsSb/InGaAsSb phototransistor for shortwave IR application are reported. The phototransistor is grown using molecular beam epitaxy technique. Spectral response measurements showed a uniform responsivity between 1.2 and 2.4 micron region with a mean value of 1000 A/W. A maximum detectivity of 3.4 X 10(exp 11) cmHz1/2/W was obtained at 2 micron at -20 C and 1.3 V.

TRIGRS Application for landslide susceptibility mapping

NASA Astrophysics Data System (ADS)

Sugiarti, K.; Sukristiyanti, S.

2018-02-01

Research on landslide susceptibility has been carried out using several different methods. TRIGRS is a modeling program for landslide susceptibility by considering pore water pressure changes due to infiltration of rainfall. This paper aims to present a current state-of-the-art science on the development and application of TRIGRS. Some limitations of TRIGRS, some developments of it to improve its modeling capability, and some examples of the applications of some versions of it to model the effect of rainfall variation on landslide susceptibility are reviewed and discussed.

Flight Controllability Limits and Related Human Transfer Functions as Determined from Simulator and Flight Tests

NASA Technical Reports Server (NTRS)

Taylor, Lawrence W., Jr.; Day, Richard E.

1961-01-01

A simulator study and flight tests were performed to determine the levels of static stability and damping necessary to enable a pilot to control the longitudinal and lateral-directional dynamics of a vehicle for short periods of time. Although a basic set of aerodynamic characteristics was used, the study was conducted so that the results would be applicable to a wide range of flight conditions and configurations. Novel piloting techniques were found which enabled the pilot to control the vehicle at conditions that were otherwise uncontrollable. The influence of several critical factors in altering the controllability limits was also investigated. Several human transfer functions were used which gave fairly good representations of the controllability limits determined experimentally for the short-period longitudinal, directional, and lateral modes. A transfer function with approximately the same gain and phase angle as the pilot at the controlling frequencies along the controllability limits was also derived.

Super-Resolution Microscopy Techniques and Their Potential for Applications in Radiation Biophysics.

PubMed

Eberle, Jan Philipp; Rapp, Alexander; Krufczik, Matthias; Eryilmaz, Marion; Gunkel, Manuel; Erfle, Holger; Hausmann, Michael

2017-01-01

Fluorescence microscopy is an essential tool for imaging tagged biological structures. Due to the wave nature of light, the resolution of a conventional fluorescence microscope is limited laterally to about 200 nm and axially to about 600 nm, which is often referred to as the Abbe limit. This hampers the observation of important biological structures and dynamics in the nano-scaled range ~10 nm to ~100 nm. Consequentially, various methods have been developed circumventing this limit of resolution. Super-resolution microscopy comprises several of those methods employing physical and/or chemical properties, such as optical/instrumental modifications and specific labeling of samples. In this article, we will give a brief insight into a variety of selected optical microscopy methods reaching super-resolution beyond the Abbe limit. We will survey three different concepts in connection to biological applications in radiation research without making a claim to be complete.

Microsphere-aided optical microscopy and its applications for super-resolution imaging

NASA Astrophysics Data System (ADS)

Upputuri, Paul Kumar; Pramanik, Manojit

2017-12-01

The spatial resolution of a standard optical microscope (SOM) is limited by diffraction. In visible spectrum, SOM can provide ∼ 200 nm resolution. To break the diffraction limit several approaches were developed including scanning near field microscopy, metamaterial super-lenses, nanoscale solid immersion lenses, super-oscillatory lenses, confocal fluorescence microscopy, techniques that exploit non-linear response of fluorophores like stimulated emission depletion microscopy, stochastic optical reconstruction microscopy, etc. Recently, photonic nanojet generated by a dielectric microsphere was used to break the diffraction limit. The microsphere-approach is simple, cost-effective and can be implemented under a standard microscope, hence it has gained enormous attention for super-resolution imaging. In this article, we briefly review the microsphere approach and its applications for super-resolution imaging in various optical imaging modalities.

Clock and trigger synchronization between several chassis of digital data acquisition modules

NASA Astrophysics Data System (ADS)

Hennig, W.; Tan, H.; Walby, M.; Grudberg, P.; Fallu-Labruyere, A.; Warburton, W. K.; Vaman, C.; Starosta, K.; Miller, D.

2007-08-01

In applications with segmented high purity Ge detectors or other detector arrays with tens or hundreds of channels, the high development cost and limited flexibility of application specific integrated circuits outweigh their benefits of low power and small size. The readout electronics typically consist of multi-channel data acquisition modules in a common chassis for power, clock and trigger distribution, and data readout. As arrays become larger and reach several hundred channels, the readout electronics have to be divided over several chassis, but still must maintain precise synchronization of clocks and trigger signals across all channels. This division becomes necessary not only because of limits given by the instrumentation standards on module size and chassis slot numbers, but also because data readout times increase when more modules share the same data bus and because power requirements approach the limits of readily available power supplies. In this paper, we present a method for distributing clocks and triggers between 4 PXI chassis containing DGF Pixie-16 modules with up to 226 acquisition channels per chassis. The data acquisition system is intended to instrument the over 600 channels of the SeGA detector array at the National Superconducting Cyclotron Laboratory. Our solution is designed to achieve synchronous acquisition of detector waveforms from all channels with a jitter of less than 1 ns, and can be extended to a larger number of chassis if desired.

Mitigation of commutation failures in LCC-HVDC systems based on superconducting fault current limiters

NASA Astrophysics Data System (ADS)

Lee, Jong-Geon; Khan, Umer Amir; Lee, Ho-Yun; Lim, Sung-Woo; Lee, Bang-Wook

2016-11-01

Commutation failure in line commutated converter based HVDC systems cause severe damages on the entire power grid system. For LCC-HVDC, thyristor valves are turned on by a firing signal but turn off control is governed by the external applied AC voltage from surrounding network. When the fault occurs in AC system, turn-off control of thyristor valves is unavailable due to the voltage collapse of point of common coupling (PCC), which causes the commutation failure in LCC-HVDC link. Due to the commutation failure, the power transfer interruption, dc voltage drop and severe voltage fluctuation in the AC system could be occurred. In a severe situation, it might cause the protection system to block the valves. In this paper, as a solution to prevent the voltage collapse on PCC and to limit the fault current, the application study of resistive superconducting fault current limiter (SFCL) on LCC-HVDC grid system was performed with mathematical and simulation analyses. The simulation model was designed by Matlab/Simulink considering Haenam-Jeju HVDC power grid in Korea which includes conventional AC system and onshore wind farm and resistive SFCL model. From the result, it was observed that the application of SFCL on LCC-HVDC system is an effective solution to mitigate the commutation failure. And then the process to determine optimum quench resistance of SFCL which enables the recovery of commutation failure was deeply investigated.

An Energy-Based Limit State Function for Estimation of Structural Reliability in Shock Environments

DOE PAGES

Guthrie, Michael A.

2013-01-01

limit state function is developed for the estimation of structural reliability in shock environments. This limit state function uses peak modal strain energies to characterize environmental severity and modal strain energies at failure to characterize the structural capacity. The Hasofer-Lind reliability index is briefly reviewed and its computation for the energy-based limit state function is discussed. Applications to two degree of freedom mass-spring systems and to a simple finite element model are considered. For these examples, computation of the reliability index requires little effort beyond a modal analysis, but still accounts for relevant uncertainties in both the structure and environment.more » For both examples, the reliability index is observed to agree well with the results of Monte Carlo analysis. In situations where fast, qualitative comparison of several candidate designs is required, the reliability index based on the proposed limit state function provides an attractive metric which can be used to compare and control reliability.« less

Comment on “Beyond the SCS-CN method: A theoretical framework for spatially lumped rainfall-runoff response” by M.S. Bartlett, A.J. Parolari, J.J. McDonnell and A. Porporato

USDA-ARS?s Scientific Manuscript database

Bartlett et al. [2016] performed a re-interpretation and modification of the space-time lumped USDA NRCS (formerly SCS) Curve Number (CN) method to extend its applicability to forested watersheds. We believe that the well documented limitations of the CN method severely constrains the applicability ...

Applications of high average power nonlinear optics

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

Velsko, S.P.; Krupke, W.F.

1996-02-05

Nonlinear optical frequency convertors (harmonic generators and optical parametric oscillators are reviewed with an emphasis on high average power performance and limitations. NLO materials issues and NLO device designs are discussed in reference to several emerging scientific, military and industrial commercial applications requiring {approx} 100 watt average power level in the visible and infrared spectral regions. Research efforts required to enable practical {approx} 100 watt class NLO based laser systems are identified.

Design of a flow perfusion bioreactor system for bone tissue-engineering applications.

PubMed

Bancroft, Gregory N; Sikavitsas, Vassilios I; Mikos, Antonios G

2003-06-01

Several different bioreactors have been investigated for tissue-engineering applications. Among these bioreactors are the spinner flask and the rotating wall vessel reactor. In addition, a new type of culture system has been developed and investigated, the flow perfusion culture bioreactor. Flow perfusion culture offers several advantages, notably the ability to mitigate both external and internal diffusional limitations as well as to apply mechanical stress to the cultured cells. For such investigation, a flow perfusion culture system was designed and built. This design is the outgrowth of important design requirements and incorporates features crucial to successful experimentation with such a system.

Application of RF-MEMS-Based Split Ring Resonators (SRRs) to the Implementation of Reconfigurable Stopband Filters: A Review

PubMed Central

Martín, Ferran; Bonache, Jordi

2014-01-01

In this review paper, several strategies for the implementation of reconfigurable split ring resonators (SRRs) based on RF-MEMS switches are presented. Essentially three types of RF-MEMS combined with split rings are considered: (i) bridge-type RF-MEMS on top of complementary split ring resonators CSRRs; (ii) cantilever-type RF-MEMS on top of SRRs; and (iii) cantilever-type RF-MEMS integrated with SRRs (or RF-MEMS SRRs). Advantages and limitations of these different configurations from the point of view of their potential applications for reconfigurable stopband filter design are discussed, and several prototype devices are presented. PMID:25474378

Moving DNA barcoding toward bioassessment application: roadmap of challenges and solutions

EPA Science Inventory

DNA barcoding holds promise for helping to address several challenges associated with taxonomic based bioassessments; these include the time and effort necessary to identify hundreds of specimens per sample location, incomplete or unavailable local taxonomy that limits the abili...

Application of antibiotics as chiral selectors for capillary electrophoretic enantioseparation of pharmaceuticals: a review.

PubMed

Dixit, Shuchi; Park, Jung Hag

2014-01-01

Recent years have witnessed several new trends in chiral separation, for example, the enantiorecognition ability of several new antibiotics has been explored using capillary electrophoresis (CE) prior to HPLC; antibiotics have been employed as chiral selectors (CSs) in a nonaqueous CE (NACE) mode; and several new detection techniques (namely, capacitively coupled contactless conductivity detection) have been used in combination with CE for quantification of enantiomers. On account of these emerging trends, this article aims to review the application of various classes of antibiotics for CE enantioseparation of pharmaceuticals. A detailed account of the basic factors affecting enantioseparation, certain limitations of antibiotics as CSs and strategies to mitigate them, and advantages of NACE while using antibiotics as CSs has also been presented. Copyright © 2013 John Wiley & Sons, Ltd.

Exciting story of the high-end television projection systems and the novel compact EIDOPHOR AE-12

NASA Astrophysics Data System (ADS)

Schulz-Hennig, Joerg F.

1998-04-01

With the new light valve technologies and availability of international broad-band communication channels high-end large screen TV projection is a highly growing contribution to the multi-media world of today. The exciting story already started 58 years ago with the invention of the EIDOPHOR diffractive oil light modulator. The long way to turn electronic cinema into a reality triggered novel applications, e.g. teleconferencing and real time surgery transmissions at universities. Several technical approaches of spatial light modulation were tried, and finally several different solutions are feasible to provide video projectors, meeting the requirements of the different display applications of today and tomorrow. The technical history is reviewed and the limitations and feasibilities of new technologies are presented in respect to existing and new applications.

Anchoring Vignettes in the Health and Retirement Study: How Do Medical Professionals and Disability Recipients Characterize the Severity of Work Limitations?

PubMed Central

Heiland, Frank; Yin, Na

2015-01-01

Purpose Recent studies report systematic differences in how individuals categorize the severity of identical health and work limitation vignettes. We investigate how health professionals and disability recipients characterize the severity of work limitations and whether their reporting patterns are robust to demographic, education, and health characteristics. We use the results to illustrate the potential impact of reporting heterogeneity on the distribution of work disability estimated from self-reported categorical health and disability data. Method Nationally representative data on anchoring disability vignettes from the 2004 Health and Retirement Study (HRS) are used to investigate how respondents with an occupation background in health and Social Security disability beneficiaries categorize work limitation vignettes. Using pain, cardiovascular health, and depression vignettes, we estimate generalized ordered probit models (N = 2,660 individuals or 39,681 person-vignette observations) that allow the severity thresholds to vary by respondent characteristics. Results We find that health professionals (excluding nurses) and disability recipients tend to classify identical work limitations as more severe compared to non-health professional non-disabled respondents. For disability recipients, the differences are most pronounced and particularly visible in the tails of the work limitations distribution. For health professionals, we observe smaller differences, affecting primarily the classification of mildly and moderately severe work limitations. The patterns for health professionals (excluding nurses) are robust to demographics, education, and health conditions. The greater likelihood of viewing the vignette person as more severely work limited observed among disability recipients is mostly explained by the fact that these respondents also tend to be in poorer health which itself predicts a more inclusive scale. Conclusions Knowledge of reporting scales from health professionals and disabled individuals can benefit researchers in a broad range of applications in health and disability research. They may be useful as reference scales to evaluate disability survey data. Such knowledge may be beneficial when studying disability programs. Given the increasing availability of anchoring vignette data in surveys, this is a promising area for future evaluation research. PMID:25966316

A low-volume cavity ring-down spectrometer for sample-limited applications

NASA Astrophysics Data System (ADS)

Stowasser, C.; Farinas, A. D.; Ware, J.; Wistisen, D. W.; Rella, C.; Wahl, E.; Crosson, E.; Blunier, T.

2014-08-01

In atmospheric and environmental sciences, optical spectrometers are used for the measurements of greenhouse gas mole fractions and the isotopic composition of water vapor or greenhouse gases. The large sample cell volumes (tens of milliliters to several liters) in commercially available spectrometers constrain the usefulness of such instruments for applications that are limited in sample size and/or need to track fast variations in the sample stream. In an effort to make spectrometers more suitable for sample-limited applications, we developed a low-volume analyzer capable of measuring mole fractions of methane and carbon monoxide based on a commercial cavity ring-down spectrometer. The instrument has a small sample cell (9.6 ml) and can selectively be operated at a sample cell pressure of 140, 45, or 20 Torr (effective internal volume of 1.8, 0.57, and 0.25 ml). We present the new sample cell design and the flow path configuration, which are optimized for small sample sizes. To quantify the spectrometer's usefulness for sample-limited applications, we determine the renewal rate of sample molecules within the low-volume spectrometer. Furthermore, we show that the performance of the low-volume spectrometer matches the performance of the standard commercial analyzers by investigating linearity, precision, and instrumental drift.

Instructional Applications of Hypermedia: Functional Features, Limitations, and Research Issues.

ERIC Educational Resources Information Center

Park, Ok-choon

1992-01-01

Defines hypermedia and describes the structure and functional requirements of a hypermedia program. Potentials of hypermedia for instructional delivery, idea generation and organization, file storage and organization, and development of computer-based instruction materials are discussed. Several research issues related to instructional…

Dissipated energy as a design parameter of coated conductors for their use in resistive fault current limiters

NASA Astrophysics Data System (ADS)

Schacherer, C.; Kudymow, A.; Noe, M.

2008-02-01

Coated conductors are suitable for many power applications like motors, magnets and superconducting fault current limiters (SCFCLs). For their use in resistive SCFCLs main requirements are quench stability and resistance development above Tc. Several coated conductors are available with different kinds of stabilization like thickness or material of cap-layer and additional stabilization. The stabilization can vary and has a great influence on the quench stability and quench behaviour of a coated conductor. Thus, for the dimensioning of a superconducting current limiting element there is a need of reliable and universal design parameters. This paper presents experimental quench test results on several coated conductor types with different stabilization and geometry. The test results show that the dissipated energy during a quench is a very useful parameter for the SCFCL design.

Frontiers in poly(ionic liquid)s: syntheses and applications.

PubMed

Qian, Wenjing; Texter, John; Yan, Feng

2017-02-20

We review recent works on the synthesis and application of poly(ionic liquid)s (PILs). Novel chemical structures, different synthetic strategies and controllable morphologies are introduced as a supplement to PIL systems already reported. The primary properties determining applications, such as ionic conductivity, aqueous solubility, thermodynamic stability and electrochemical/chemical durability, are discussed. Furthermore, the near-term applications of PILs in multiple fields, such as their use in electrochemical energy materials, stimuli-responsive materials, carbon materials, and antimicrobial materials, in catalysis, in sensors, in absorption and in separation materials, as well as several special-interest applications, are described in detail. We also discuss the limitations of PIL applications, efforts to improve PIL physics, and likely future developments.

Free-space optical communications research and demonstrations at the U.S. Naval Research Laboratory.

PubMed

Rabinovich, W S; Moore, C I; Mahon, R; Goetz, P G; Burris, H R; Ferraro, M S; Murphy, J L; Thomas, L M; Gilbreath, G C; Vilcheck, M; Suite, M R

2015-11-01

Free-space optical communication can allow high-bandwidth data links that are hard to detect, intercept, or jam. This makes them attractive for many applications. However, these links also require very accurate pointing, and their availability is affected by weather. These challenges have limited the deployment of free-space optical systems. The U.S. Naval Research Laboratory has, for the last 15 years, engaged in research into atmospheric propagation and photonic components with a goal of characterizing and overcoming these limitations. In addition several demonstrations of free-space optical links in real-world Navy applications have been conducted. This paper reviews this work and the principles guiding it.

Low noise scintillation detectors with a P-47 thin layer screen for electrons of several keV

NASA Astrophysics Data System (ADS)

Kajcsos, Zs.; Meisel, W.; Griesbach, P.; Gütlich, P.; Sauer, Ch.; Kurz, R.; Hildebrand, K.; Albrecht, R.; Ligtenberg, M. A. C.

1994-09-01

The applicability of a low-noise scintillation detector (ScD) for the registration of electrons of several keV energy has been studied employing photomultipliers (PM) of different types and sizes. With the application of a sedimented P-47 scintillation screen, the values of the low-energy sensitivity limit and those of the light conversion coefficient were determined as about 2.7-4.7 keV and 2.8-6.6 photoelectrons/keV, respectively, for the set of PM's (Philips-Valvo XP 2020, Philips-Valvo XP 2052, Philips-Valvo XP 2972, EMI 9124a) studied. It is concluded that such scintillation detectors might be used advantageously as electron counters in the range of E > 5 keV. Applications below this kinetic energy value are also feasible when applying a floating acceleration of several kV to the ScD — a voltage much lower than the values required for Everhart-Thornley detectors.

Underwater lidar system: design challenges and application in pollution detection

NASA Astrophysics Data System (ADS)

Gupta, Pradip; Sankolli, Swati; Chakraborty, A.

2016-05-01

The present remote sensing techniques have imposed limitations in the applications of LIDAR Technology. The fundamental sampling inadequacy of the remote sensing data obtained from satellites is that they cannot resolve in the third spatial dimension, the vertical. This limits our possibilities of measuring any vertical variability in the water column. Also the interaction between the physical and biological process in the oceans and their effects at subsequent depths cannot be modeled with present techniques. The idea behind this paper is to introduce underwater LIDAR measurement system by using a LIDAR mounted on an Autonomous Underwater Vehicle (AUV). The paper introduces working principles and design parameters for the LIDAR mounted AUV (AUV-LIDAR). Among several applications the papers discusses the possible use and advantages of AUV-LIDAR in water pollution detection through profiling of Dissolved Organic Matter (DOM) in water bodies.

Impact of chitosan application technique on refrigerated catfish fillet quality

USDA-ARS?s Scientific Manuscript database

Chitosan has been reported to have functional properties such as antimicrobial activity, antioxidant activity, and binding action. Several studies reported an extension in the shelf life of various food products when chitosan was applied. However, there is limited study on the effect of chitosan ap...

Optimizing Alternative Fumigant Applications for Ornamental Production in Florida

USDA-ARS?s Scientific Manuscript database

In Florida, cut flower and other ornamental crop producers have a very limited number of alternatives to methyl bromide for several reasons including the lack of registered herbicides available for these crops, and the need to control previously planted cultivars volunteering as weeds within the sam...

Turkish School Counselors and Counselor Educators' Perceptions about Multicultural Counseling

ERIC Educational Resources Information Center

Hatunoglu, Askim

2017-01-01

This paper examines the topic of multicultural counseling in Turkey, where school-based multicultural counseling services remain comparatively limited in scope and application. Participants consisted of twenty-three counselors working in secondary or high schools and fourteen counselor educators from several state universities. While the…

Quantitative real-time PCR approaches for microbial community studies in wastewater treatment systems: applications and considerations.

PubMed

Kim, Jaai; Lim, Juntaek; Lee, Changsoo

2013-12-01

Quantitative real-time PCR (qPCR) has been widely used in recent environmental microbial ecology studies as a tool for detecting and quantifying microorganisms of interest, which aids in better understandings of the complexity of wastewater microbial communities. Although qPCR can be used to provide more specific and accurate quantification than other molecular techniques, it does have limitations that must be considered when applying it in practice. This article reviews the principle of qPCR quantification and its applications to microbial ecology studies in various wastewater treatment environments. Here we also address several limitations of qPCR-based approaches that can affect the validity of quantification data: template nucleic acid quality, nucleic acid extraction efficiency, specificity of group-specific primers and probes, amplification of nonviable DNA, gene copy number variation, and limited number of sequences in the database. Even with such limitations, qPCR is reportedly among the best methods for quantitatively investigating environmental microbial communities. The application of qPCR is and will continue to be increasingly common in studies of wastewater treatment systems. To obtain reliable analyses, however, the limitations that have often been overlooked must be carefully considered when interpreting the results. Copyright © 2013 Elsevier Inc. All rights reserved.

Electromagnetic Considerations for Planar Bolometer Arrays in the Single Mode Limit

NASA Technical Reports Server (NTRS)

Wollack, Edward J.; Chuss, David T.; Moseley, Samuel

2006-01-01

Filled arrays of planar bolometers are finding astronomical applications at wavelengths as long as several millimeters. In an effort to keep focal planes to a reasonable size while maintaining large numbers of detectors, a common strategy is to push these arrays to operate close to or at the single mode limit. Doing so introduces several new challenges that are not experienced in the multi-mode case of far-infrared detectors having similar pixel sizes. First, diffractive effects of the pixels themselves are no longer insignificant and will ultimately contribute to the resolution limit of the optical system in which they reside. We use the method of Withlngton et al. (2003) to model the polarized diffraction in this limit. Second, it is necessary to re-examine the coupling between the radiation and the absorbing element that is thermally connected to the bolometers. The small f-numbers that are often employed to make use of large focal planes makes backshort construction problematic. We introduce a new strategy to increase detector efficiency that uses an antireflective layer on the front side of the detector array. In addition, typical methods for stray light control that rely on multiple reflections in a lossy medium fail due to physical size constraints. For this application, we find that resonant absorbers are a more effective strategy that can be implemented in the space available.

Engineering resistance to plant viruses: Present status and future prospects

USDA-ARS?s Scientific Manuscript database

Plant viruses cause severe crop losses across the globe. Resistant cultivars together with pesticide application are commonly used to avoid the losses caused by plant viruses. However, very limited success has been achieved at diminishing the impact of plant viruses. Use of virus resistant plant is ...

An evaluation of the effectiveness of voice-to-text programs at reducing incidences of distracted driving.

DOT National Transportation Integrated Search

2013-04-01

Text messaging is no longer limited to manual-entry. There are several mobile applications that aim to assist the driver in sending and receiving text messages by incorporating a voice-to-text component. To date, there has been no published research ...

Analysis of Fixed Duty Cycle Hysteretic Flyback Converter for Firing Set Applications.

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

Love, Thomas Michael

2017-05-01

This paper analyzes several performance aspects of the fixed-duty-cycle, hysteretic flyback converter topology typically used in firing sets. Topologies with and without active pulse-by-pulse current limiting are considered, and closed-form expressions in terms of basic operating parameters are derived.

Molecular Diversity of Bacteroidales in Fecal and Environmental Samples and Swine-Associated Subpopulations

EPA Science Inventory

Several swine-specific microbial source tracking methods are based on PCR assays targeting Bacteroidales 16S rRNA gene sequences. The limited application of these assays can be explained by the poor understanding of their molecular diversity in fecal sources and environmental wat...

Designing and Researching Technology-Enhanced Learning for the Zone of Proximal Implementation

ERIC Educational Resources Information Center

McKenney, Susan

2013-01-01

Internationally, society is increasingly demanding that the relevance and practical applicability of research be made transparent. Despite intentions to the contrary, insights on pedagogically appropriate uses of educational technology for representative teachers in everyday school settings are severely limited. In part, this is because (design)…

Yokoi's Theory of Lateral Innovation: Applications for Learning Game Design

ERIC Educational Resources Information Center

Warren, Scott J.; Jones, Greg

2008-01-01

There are several major challenges for instructional designers seeking to design learning games. These include the lack of access, the cost of rapidly advancing/expensive technology tools that make developing games uneconomical, the institutional time constraints limiting game use, and the concerns that schools lack sufficiently robust computer…

7 CFR 1718.103 - Loan contract provisions.

Code of Federal Regulations, 2010 CFR

2010-01-01

... contract and the remedies available to RUS; (v) Applicability of state and federal laws; (w) Severability... loan contract; (y) Requirements relating to federal laws and regulations, including but not limited to... 7 Agriculture 11 2010-01-01 2010-01-01 false Loan contract provisions. 1718.103 Section 1718.103...

Fly ashes from coal and petroleum coke combustion: current and innovative potential applications.

PubMed

González, Aixa; Navia, Rodrigo; Moreno, Natalia

2009-12-01

Coal fly ashes (CFA) are generated in large amounts worldwide. Current combustion technologies allow the burning of fuels with high sulfur content such as petroleum coke, generating non-CFA, such as petroleum coke fly ash (PCFA), mainly from fluidized bed combustion processes. The disposal of CFA and PCFA fly ashes can have severe impacts in the environment such as a potential groundwater contamination by the leaching of heavy metals and/or particulate matter emissions; making it necessary to treat or reuse them. At present CFA are utilized in several applications fields such as cement and concrete production, agriculture and soil stabilization. However, their reuse is restricted by the quality parameters of the end-product or requirements defined by the production process. Therefore, secondary material markets can use a limited amount of CFA, which implies the necessity of new markets for the unused CFA. Some potential future utilization options reviewed herein are zeolite synthesis and valuable metals extraction. In comparison to CFA, PCFA are characterized by a high Ca content, suggesting a possible use as neutralizers of acid wastewaters from mining operations, opening a new potential application area for PCFA that could solve contamination problems in emergent and mining countries such as Chile. However, this potential application may be limited by PCFA heavy metals leaching, mainly V and Ni, which are present in PCFA in high concentrations.

The effect of erosion on the fatigue limit of metallic materials for aerospace applications

NASA Astrophysics Data System (ADS)

Kordatos, E. Z.; Exarchos, D. A.; Matikas, T. E.

2018-03-01

This work deals with the study of the fatigue behavior of metallic materials for aerospace applications which have undergone erosion. Particularly, an innovative non-destructive methodology based on infrared lock-in thermography was applied on aluminum samples for the rapid determination of their fatigue limit. The effect of erosion on the structural integrity of materials can lead to a catastrophic failure and therefore an efficient assessment of the fatigue behavior is of high importance. Infrared thermography (IRT) as a non-destructive, non-contact, real time and full field method can be employed in order the fatigue limit to be rapidly determined. The basic principle of this method is the detection and monitoring of the intrinsically dissipated energy due to the cyclic fatigue loading. This methodology was successfully applied on both eroded and non-eroded aluminum specimens in order the severity of erosion to be evaluated.

Averaging scheme for atomic resolution off-axis electron holograms.

PubMed

Niermann, T; Lehmann, M

2014-08-01

All micrographs are limited by shot-noise, which is intrinsic to the detection process of electrons. For beam insensitive specimen this limitation can in principle easily be circumvented by prolonged exposure times. However, in the high-resolution regime several instrumental instabilities limit the applicable exposure time. Particularly in the case of off-axis holography the holograms are highly sensitive to the position and voltage of the electron-optical biprism. We present a novel reconstruction algorithm to average series of off-axis holograms while compensating for specimen drift, biprism drift, drift of biprism voltage, and drift of defocus, which all might cause problematic changes from exposure to exposure. We show an application of the algorithm utilizing also the possibilities of double biprism holography, which results in a high quality exit-wave reconstruction with 75 pm resolution at a very high signal-to-noise ratio. Copyright © 2014 Elsevier Ltd. All rights reserved.

Large-D gravity and low-D strings.

PubMed

Emparan, Roberto; Grumiller, Daniel; Tanabe, Kentaro

2013-06-21

We show that in the limit of a large number of dimensions a wide class of nonextremal neutral black holes has a universal near-horizon limit. The limiting geometry is the two-dimensional black hole of string theory with a two-dimensional target space. Its conformal symmetry explains the properties of massless scalars found recently in the large-D limit. For black branes with string charges, the near-horizon geometry is that of the three-dimensional black strings of Horne and Horowitz. The analogies between the α' expansion in string theory and the large-D expansion in gravity suggest a possible effective string description of the large-D limit of black holes. We comment on applications to several subjects, in particular to the problem of critical collapse.

Scientific applications of frequency-stabilized laser technology in space

NASA Technical Reports Server (NTRS)

Schumaker, Bonny L.

1990-01-01

A synoptic investigation of the uses of frequency-stabilized lasers for scientific applications in space is presented. It begins by summarizing properties of lasers, characterizing their frequency stability, and describing limitations and techniques to achieve certain levels of frequency stability. Limits to precision set by laser frequency stability for various kinds of measurements are investigated and compared with other sources of error. These other sources include photon-counting statistics, scattered laser light, fluctuations in laser power, and intensity distribution across the beam, propagation effects, mechanical and thermal noise, and radiation pressure. Methods are explored to improve the sensitivity of laser-based interferometric and range-rate measurements. Several specific types of science experiments that rely on highly precise measurements made with lasers are analyzed, and anticipated errors and overall performance are discussed. Qualitative descriptions are given of a number of other possible science applications involving frequency-stabilized lasers and related laser technology in space. These applications will warrant more careful analysis as technology develops.

Recent Trends in Nanotechnology-Based Drugs and Formulations for Targeted Therapeutic Delivery.

PubMed

Iqbal, Hafiz M N; Rodriguez, Angel M V; Khandia, Rekha; Munjal, Ashok; Dhama, Kuldeep

2017-01-01

In the recent past, a wider spectrum of nanotechnologybased drugs or drug-loaded devices and systems has been engineered and investigated with high interests. The key objective is to help for an enhanced/better quality of patient life in a secure way by avoiding/limiting drug abuse, or severe adverse effects of some in practice traditional therapies. Various methodological approaches including in vitro, in vivo, and ex vivo techniques have been exploited, so far. Among them, nanoparticles-based therapeutic agents are of supreme interests for an enhanced and efficient delivery in the current biomedical sector of the modern world. The development of new types of novel, effective and highly reliable therapeutic drug delivery system (DDS) for multipurpose applications is essential and a core demand to tackle many human health related diseases. In this context, nanotechnology-based several advanced DDS have been engineered with novel characteristics for biomedical, pharmaceutical and cosmeceutical applications that include but not limited to the enhanced/improved bioactivity, bioavailability, drug efficacy, targeted delivery, and therapeutically safer with an extra advantage of overcoming demerits of traditional drug formulations/designs. This review work is focused on recent trends/advances in nanotechnology-based drugs and formulations designed for targeted therapeutic delivery. Moreover, information is also reviewed and given from recent patents and summarized or illustrated diagrammatically to depict a better understanding. Recent patents covering various nanotechnology-based approaches for several applications have also been reviewed. The drug-loaded nanoparticles are among versatile candidates with multifunctional characteristics for potential applications in biomedical, and tissue engineering sector. Copyright© Bentham Science Publishers; For any queries, please email at epub@benthamscience.org.

Controlling chaos faster.

PubMed

Bick, Christian; Kolodziejski, Christoph; Timme, Marc

2014-09-01

Predictive feedback control is an easy-to-implement method to stabilize unknown unstable periodic orbits in chaotic dynamical systems. Predictive feedback control is severely limited because asymptotic convergence speed decreases with stronger instabilities which in turn are typical for larger target periods, rendering it harder to effectively stabilize periodic orbits of large period. Here, we study stalled chaos control, where the application of control is stalled to make use of the chaotic, uncontrolled dynamics, and introduce an adaptation paradigm to overcome this limitation and speed up convergence. This modified control scheme is not only capable of stabilizing more periodic orbits than the original predictive feedback control but also speeds up convergence for typical chaotic maps, as illustrated in both theory and application. The proposed adaptation scheme provides a way to tune parameters online, yielding a broadly applicable, fast chaos control that converges reliably, even for periodic orbits of large period.

Dominating Scale-Free Networks Using Generalized Probabilistic Methods

PubMed Central

Molnár,, F.; Derzsy, N.; Czabarka, É.; Székely, L.; Szymanski, B. K.; Korniss, G.

2014-01-01

We study ensemble-based graph-theoretical methods aiming to approximate the size of the minimum dominating set (MDS) in scale-free networks. We analyze both analytical upper bounds of dominating sets and numerical realizations for applications. We propose two novel probabilistic dominating set selection strategies that are applicable to heterogeneous networks. One of them obtains the smallest probabilistic dominating set and also outperforms the deterministic degree-ranked method. We show that a degree-dependent probabilistic selection method becomes optimal in its deterministic limit. In addition, we also find the precise limit where selecting high-degree nodes exclusively becomes inefficient for network domination. We validate our results on several real-world networks, and provide highly accurate analytical estimates for our methods. PMID:25200937

Application of Bayesian Approach in Cancer Clinical Trial

PubMed Central

Bhattacharjee, Atanu

2014-01-01

The application of Bayesian approach in clinical trials becomes more useful over classical method. It is beneficial from design to analysis phase. The straight forward statement is possible to obtain through Bayesian about the drug treatment effect. Complex computational problems are simple to handle with Bayesian techniques. The technique is only feasible to performing presence of prior information of the data. The inference is possible to establish through posterior estimates. However, some limitations are present in this method. The objective of this work was to explore the several merits and demerits of Bayesian approach in cancer research. The review of the technique will be helpful for the clinical researcher involved in the oncology to explore the limitation and power of Bayesian techniques. PMID:29147387

All optical logic for optical pattern recognition and networking applications

NASA Astrophysics Data System (ADS)

Khoury, Jed

2017-05-01

In this paper, we propose architectures for the implementation 16 Boolean optical gates from two inputs using externally pumped phase- conjugate Michelson interferometer. Depending on the gate to be implemented, some require single stage interferometer and others require two stages interferometer. The proposed optical gates can be used in several applications in optical networks including, but not limited to, all-optical packet routers switching, and all-optical error detection. The optical logic gates can also be used in recognition of noiseless rotation and scale invariant objects such as finger prints for home land security applications.

Protoporphyrin IX fluorescence as potential indicator of psoriasis severity and progression.

PubMed

Wang, Bo; Xu, Yu-Ting; Zhang, Li; Zheng, Jie; Sroka, Ronald; Wang, Hong-Wei; Wang, Xiu-Li

2017-09-01

In psoriatic lesions, fluorescence diagnosis with blue light can detect protoporphyrin IX accumulation, especially after topical 5-aminolaevulinic acid (ALA) application. However, variable fluorescence distributions, interpersonal variations and long incubation time limit its wide application in clinic. This study is aimed to identify a consistent and convenient method to facilitate diagnosis and evaluation of psoriatic lesions. 104 psoriatic lesions from 30 patients were evaluated. Single lesion PSI scoring and fluorescence by macrospectrofluorometry were recorded on each lesion before and after treatment with narrow-band UVB. Punctate red fluorescence, emitted mainly by protoporphyrin IX, is observed in some psoriatic lesions. According to psoriasis severity index, fluorescence-positive lesions are more severe than lesions without fluorescence. We found a significant positive correlation between psoriasis severity and fluorescence intensity from protoporphyrin IX. Protoporphyrin IX-induced red fluorescence can be used as a novel and convenient approach for psoriasis diagnosis and progression evaluation. Copyright © 2017. Published by Elsevier B.V.

Optical Coherence Tomography: Basic Concepts and Applications in Neuroscience Research

PubMed Central

2017-01-01

Optical coherence tomography is a micrometer-scale imaging modality that permits label-free, cross-sectional imaging of biological tissue microstructure using tissue backscattering properties. After its invention in the 1990s, OCT is now being widely used in several branches of neuroscience as well as other fields of biomedical science. This review study reports an overview of OCT's applications in several branches or subbranches of neuroscience such as neuroimaging, neurology, neurosurgery, neuropathology, and neuroembryology. This study has briefly summarized the recent applications of OCT in neuroscience research, including a comparison, and provides a discussion of the remaining challenges and opportunities in addition to future directions. The chief aim of the review study is to draw the attention of a broad neuroscience community in order to maximize the applications of OCT in other branches of neuroscience too, and the study may also serve as a benchmark for future OCT-based neuroscience research. Despite some limitations, OCT proves to be a useful imaging tool in both basic and clinical neuroscience research. PMID:29214158

Colossal spin-orbit coupling in functionalized graphene

NASA Astrophysics Data System (ADS)

Balakrishnan, Jayakumar; Koon, Gavin; Oezyilmaz, Barbaros

2013-03-01

Graphene's low intrinsic spin orbit (SO) interaction strongly limits the realization of several functional spintronics devices. It is therefore quite desirable to develop methods to tune this SO coupling strength. Among the different approaches, the functionalization of graphene seems to be more promising from an application perspective. Recent theoretical and experimental results on functionalized graphene have shown interesting magnetic properties. Here, we will show our preliminary spin-transport results on such functionally modified graphene and discuss the various possibilities it holds for future graphene-based spintronics applications.

Introduction to the Special Issue: Application of Essential Oils in Food Systems.

PubMed

Fernández-López, Juana; Viuda-Martos, Manuel

2018-04-05

Essential oils have received increasing attention as natural additives for the shelf-life extension of food products due to the risk in using synthetic preservatives. Synthetic additives can reduce food spoilage, but the present generation is very health conscious and believes in natural products rather than synthetic ones due to their potential toxicity and other concerns. Therefore, one of the major emerging technologies is the extraction of essential oils from several plant organs and their application to foods. Essential oils are a good source of several bioactive compounds, which possess antioxidative and antimicrobial properties, so their use can be very useful to extend shelf-life in food products. Although essential oils have been shown to be promising alternative to chemical preservatives, they present special limitations that must be solved before their application in food systems. Low water solubility, high volatility, and strong odor are the main properties that make it difficult for food applications. Recent advances that refer to new forms of application to avoid these problems are currently under study. Their application into packaging materials and coated films but also directly into the food matrix as emulsions, nanoemulsions, and coating are some of their new applications among others.

Introduction to the Special Issue: Application of Essential Oils in Food Systems

PubMed Central

Fernández-López, Juana

2018-01-01

Essential oils have received increasing attention as natural additives for the shelf-life extension of food products due to the risk in using synthetic preservatives. Synthetic additives can reduce food spoilage, but the present generation is very health conscious and believes in natural products rather than synthetic ones due to their potential toxicity and other concerns. Therefore, one of the major emerging technologies is the extraction of essential oils from several plant organs and their application to foods. Essential oils are a good source of several bioactive compounds, which possess antioxidative and antimicrobial properties, so their use can be very useful to extend shelf-life in food products. Although essential oils have been shown to be promising alternative to chemical preservatives, they present special limitations that must be solved before their application in food systems. Low water solubility, high volatility, and strong odor are the main properties that make it difficult for food applications. Recent advances that refer to new forms of application to avoid these problems are currently under study. Their application into packaging materials and coated films but also directly into the food matrix as emulsions, nanoemulsions, and coating are some of their new applications among others. PMID:29621143

Bridging the gap between fluxomics and industrial biotechnology.

PubMed

Feng, Xueyang; Page, Lawrence; Rubens, Jacob; Chircus, Lauren; Colletti, Peter; Pakrasi, Himadri B; Tang, Yinjie J

2010-01-01

Metabolic flux analysis is a vital tool used to determine the ultimate output of cellular metabolism and thus detect biotechnologically relevant bottlenecks in productivity. ¹³C-based metabolic flux analysis (¹³C-MFA) and flux balance analysis (FBA) have many potential applications in biotechnology. However, noteworthy hurdles in fluxomics study are still present. First, several technical difficulties in both ¹³C-MFA and FBA severely limit the scope of fluxomics findings and the applicability of obtained metabolic information. Second, the complexity of metabolic regulation poses a great challenge for precise prediction and analysis of metabolic networks, as there are gaps between fluxomics results and other omics studies. Third, despite identified metabolic bottlenecks or sources of host stress from product synthesis, it remains difficult to overcome inherent metabolic robustness or to efficiently import and express nonnative pathways. Fourth, product yields often decrease as the number of enzymatic steps increases. Such decrease in yield may not be caused by rate-limiting enzymes, but rather is accumulated through each enzymatic reaction. Fifth, a high-throughput fluxomics tool hasnot been developed for characterizing nonmodel microorganisms and maximizing their application in industrial biotechnology. Refining fluxomics tools and understanding these obstacles will improve our ability to engineer highly efficient metabolic pathways in microbial hosts.

Multi-application controls: Robust nonlinear multivariable aerospace controls applications

NASA Technical Reports Server (NTRS)

Enns, Dale F.; Bugajski, Daniel J.; Carter, John; Antoniewicz, Bob

1994-01-01

This viewgraph presentation describes the general methodology used to apply Honywell's Multi-Application Control (MACH) and the specific application to the F-18 High Angle-of-Attack Research Vehicle (HARV) including piloted simulation handling qualities evaluation. The general steps include insertion of modeling data for geometry and mass properties, aerodynamics, propulsion data and assumptions, requirements and specifications, e.g. definition of control variables, handling qualities, stability margins and statements for bandwidth, control power, priorities, position and rate limits. The specific steps include choice of independent variables for least squares fits to aerodynamic and propulsion data, modifications to the management of the controls with regard to integrator windup and actuation limiting and priorities, e.g. pitch priority over roll, and command limiting to prevent departures and/or undesirable inertial coupling or inability to recover to a stable trim condition. The HARV control problem is characterized by significant nonlinearities and multivariable interactions in the low speed, high angle-of-attack, high angular rate flight regime. Systematic approaches to the control of vehicle motions modeled with coupled nonlinear equations of motion have been developed. This paper will discuss the dynamic inversion approach which explicity accounts for nonlinearities in the control design. Multiple control effectors (including aerodynamic control surfaces and thrust vectoring control) and sensors are used to control the motions of the vehicles in several degrees-of-freedom. Several maneuvers will be used to illustrate performance of MACH in the high angle-of-attack flight regime. Analytical methods for assessing the robust performance of the multivariable control system in the presence of math modeling uncertainty, disturbances, and commands have reached a high level of maturity. The structured singular value (mu) frequency response methodology is presented as a method for analyzing robust performance and the mu-synthesis method will be presented as a method for synthesizing a robust control system. The paper concludes with the author's expectations regarding future applications of robust nonlinear multivariable controls.

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.

Clinical application of diffusion tensor magnetic resonance imaging in skeletal muscle

PubMed Central

Longwei, Xu

2012-01-01

Summary Diffusion tensor magnetic resonance imaging (DTI) is increasingly applied in the detection and characterization of skeletal muscle. This promising technique has aroused much enthusiasm and generated high expectations, because it is able to provide some specific information of skeletal muscle that is not available from other imaging modalities. Compared with conventional MRI, DTI could reconstruct the trajectories of skeletal muscle fibers. It makes it possible to non-invasively detect several physiological values (diffusion values), like fractional anisotropy (FA) and apparent diffusion coefficient (ADC), which have a great association with the muscle physiology and pathology. Furthermore, other advantages of DTI are the capability of investigating the muscle biomechanics and also investigate the pathological condition of skeletal muscle. Finally, several challenges, which limit the wide application of DTI in skeletal muscle, were discussed. It is believed that this review may arouse in-depth studies on the clinical application of DTI in skeletal muscle in future. PMID:23738269

Skill Assessment for Coupled Biological/Physical Models of Marine Systems.

PubMed

Stow, Craig A; Jolliff, Jason; McGillicuddy, Dennis J; Doney, Scott C; Allen, J Icarus; Friedrichs, Marjorie A M; Rose, Kenneth A; Wallhead, Philip

2009-02-20

Coupled biological/physical models of marine systems serve many purposes including the synthesis of information, hypothesis generation, and as a tool for numerical experimentation. However, marine system models are increasingly used for prediction to support high-stakes decision-making. In such applications it is imperative that a rigorous model skill assessment is conducted so that the model's capabilities are tested and understood. Herein, we review several metrics and approaches useful to evaluate model skill. The definition of skill and the determination of the skill level necessary for a given application is context specific and no single metric is likely to reveal all aspects of model skill. Thus, we recommend the use of several metrics, in concert, to provide a more thorough appraisal. The routine application and presentation of rigorous skill assessment metrics will also serve the broader interests of the modeling community, ultimately resulting in improved forecasting abilities as well as helping us recognize our limitations.

Integrating Data from GRACE and Other Observing Systems for Hydrological Research and Applications

NASA Technical Reports Server (NTRS)

Rodell, M.; Famiglietti, J. S.; McWilliams, E.; Beaudoing, H. K.; Li, B.; Zaitchik, B.; Reichle, R.; Bolten, J.

2011-01-01

The Gravity Recovery and Climate Experiment (GRACE) mission provides a unique view of water cycle dynamics, enabling the only space based observations of water on and beneath the land surface that are not limited by depth. GRACE data are immediately useful for large scale applications such as ice sheet ablation monitoring, but they are even more valuable when combined with other types of observations, either directly or within a data assimilation system. Here we describe recent results of hydrological research and applications projects enabled by GRACE. These include the following: 1) global monitoring of interannual variability of terrestrial water storage and groundwater; 2) water balance estimates of evapotranspiration over several large river basins; 3) NASA's Energy and Water Cycle Study (NEWS) state of the global water budget project; 4) drought indicator products now being incorporated into the U.S. Drought Monitor; 5) GRACE data assimilation over several regions.

Application of Multiple Categories of Unmanned Aircraft Systems (uas) in Different Airspaces for Bushfire Monitoring and Response

NASA Astrophysics Data System (ADS)

Homainejad, N.; Rizos, C.

2015-08-01

Demand and interest in Unmanned Aircraft Systems (UAS) for civilian applications, and advances in technology such as development of sense-and-avoid systems, will soon allow UAS to be flown alongside manned aircrafts in non-segregated airspace. An area that can benefit from the application of UAS is the bushfire services sector. Currently such services rely on watchtowers, fixed-wing manned aircrafts and satellite data for reliable information. UAS are a promising alternative to traditional methods of collecting bushfire data. There are several varieties of UAS and each category has certain limitations, hence a combination of multiple UAS with features appropriate for bushfire emergencies can be used simultaneously for collecting valuable data. This paper will describe the general UAS categories, some characteristics of Australian bushfires, and speculate on how a combination of several UAS operating in different airspaces can be of benefit for bushfire response personnel and firefighters.

Efficacy of Fungicides for Control of Rosette and Post-harvest Fruit Diseases of Blackberries

USDA-ARS?s Scientific Manuscript database

Rosette disease (caused by the fungus Cercosporella rubi) is often severe on erect blackberries grown in the southeastern U.S. and, if not controlled, may limit fruit production. A series of trials were conducted in south Mississippi to determine fungicide efficacy and optimum timing of applications...

Repeated insect outbreaks promote multi-cohort aspen mixedwood forests in Northern Minnesota, USA

Treesearch

Michael Reinikainen; Anthony W. D' Amato; Shawn. Fraver

2012-01-01

Characterizing the timing, severity, and agents of historic forest disturbances is critical to developing management and conservation strategies based on natural processes. Typically such information is derived from retrospective studies of remnant old-growth forests; however, this approach has limited application in regions dominated by secondary forests heavily...

Synergistic effect of dual imidacloprid-Metarhizium anisopliae applications against Asian longhorned beetles (Anoplophora glabripennis)

Treesearch

Todd A. Ugine; Calum W. Russell; Ann E. Hajek

2011-01-01

Anoplophora glabripennis (Motschulsky) (Coleoptera: Cerambycidae), a longhorned beetle species native to Asia, has been introduced into several North American and European cities. Currently, eradication and preventive measures are limited to identifying and destroying infested trees and protecting uninfested trees with trunk or soil-injections of the...

Efficacy of Steinernema carpocapsae plus fire gel applied as a single spray for control of the lesser peachtree borer, Synanthedon pictipes

USDA-ARS?s Scientific Manuscript database

The efficacy of aboveground applications of entomopathogenic nematodes (Heterorhabditis spp. and Steinernema spp.) can be severely limited by the nematode’s susceptibility to UV radiation and desiccation. The lesser peachtree borer, Synanthedon pictipes, a major pest of stone fruit; larvae attack t...

An Inside View: The Utility of Quantitative Observation in Understanding College Educational Experiences

ERIC Educational Resources Information Center

Campbell, Corbin M.

2017-01-01

This article describes quantitative observation as a method for understanding college educational experiences. Quantitative observation has been used widely in several fields and in K-12 education, but has had limited application to research in higher education and student affairs to date. The article describes the central tenets of quantitative…

Flexible Unicast-Based Group Communication for CoAP-Enabled Devices †

PubMed Central

Ishaq, Isam; Hoebeke, Jeroen; Van den Abeele, Floris; Rossey, Jen; Moerman, Ingrid; Demeester, Piet

2014-01-01

Smart embedded objects will become an important part of what is called the Internet of Things. Applications often require concurrent interactions with several of these objects and their resources. Existing solutions have several limitations in terms of reliability, flexibility and manageability of such groups of objects. To overcome these limitations we propose an intermediately level of intelligence to easily manipulate a group of resources across multiple smart objects, building upon the Constrained Application Protocol (CoAP). We describe the design of our solution to create and manipulate a group of CoAP resources using a single client request. Furthermore we introduce the concept of profiles for the created groups. The use of profiles allows the client to specify in more detail how the group should behave. We have implemented our solution and demonstrate that it covers the complete group life-cycle, i.e., creation, validation, flexible usage and deletion. Finally, we quantitatively analyze the performance of our solution and compare it against multicast-based CoAP group communication. The results show that our solution improves reliability and flexibility with a trade-off in increased communication overhead. PMID:24901978

Nilsson's Power Model connecting speed and road trauma: applicability by road type and alternative models for urban roads.

PubMed

Cameron, M H; Elvik, R

2010-11-01

Nilsson (1981) proposed power relationships connecting changes in traffic speeds with changes in road crashes at various levels of injury severity. Increases in fatal crashes are related to the 4(th) power of the increase in mean speed, increases in serious casualty crashes (those involving death or serious injury) according to the 3(rd) power, and increases in casualty crashes (those involving death or any injury) according to the 2(nd) power. Increases in numbers of crash victims at cumulative levels of injury severity are related to the crash increases plus higher powers predicting the number of victims per crash. These relationships are frequently applied in OECD countries to estimate road trauma reductions resulting from expected speed reductions. The relationships were empirically derived based on speed changes resulting from a large number of rural speed limit changes in Sweden during 1967-1972. Nilsson (2004) noted that there had been very few urban speed limit changes studied to test his power model. This paper aims to test the assumption that the model is equally applicable in all road environments. It was found that the road environment is an important moderator of Nilsson's power model. While Nilsson's model appears satisfactory for rural highways and freeways, the model does not appear to be directly applicable to traffic speed changes on urban arterial roads. The evidence of monotonically increasing powers applicable to changes in road trauma at increasing injury severity levels with changes in mean speed is weak. The estimated power applicable to serious casualties on urban arterial roads was significantly less than that on rural highways, which was also significantly less than that on freeways. Alternative models linking the parameters of speed distributions with road trauma are reviewed and some conclusions reached for their use on urban roads instead of Nilsson's model. Further research is needed on the relationships between serious road trauma and urban speeds. 2010 Elsevier Ltd. All rights reserved.

Developing improved silica materials and devices for integrated optics applications

NASA Astrophysics Data System (ADS)

Maker, Ashley Julia

Due to their favorable optical and material properties, silica-based materials and devices have found many important applications throughout science and engineering, especially in sensing, communications, lasers, and integrated optics. Often, silica's properties ultimately limit the performance of these applications. To address this limitation, this thesis investigates the development of improved silica materials and optical devices, including silica films, coatings, waveguides, resonators, lasers, and sensors. Using sol-gel chemistry and microfabrication procedures, custom silica materials and devices are developed to benefit many applications. In this thesis, it is first demonstrated how the low optical loss of silica enables fabrication of low loss integrated waveguides and toroidal resonators with ultra-high quality factors. Then, by adding various rare earth and metal dopants to sol-gel silica, hybrid silica materials and devices are made with custom properties such as high refractive index and lasing capabilities. Finally, several applications are demonstrated, including the use of high refractive index coatings to control the behavior of light, development of Raman and ultra-low threshold rare earth microlasers, and a heterodyned microlaser sensor with significantly improved sensing performance. Future applications and directions of this research are also discussed.

Towards Low-Cost Effective and Homogeneous Thermal Activation of Shape Memory Polymers

PubMed Central

Lantada, Andrés Díaz; Rebollo, María Ángeles Santamaría

2013-01-01

A typical limitation of intelligent devices based on the use of shape-memory polymers as actuators is linked to the widespread use of distributed heating resistors, via Joule effect, as activation method, which involves several relevant issues needing attention, such as: (a) Final device size is importantly increased due to the additional space required for the resistances; (b) the use of resistances limits materials’ strength and the obtained devices are normally weaker; (c) the activation process through heating resistances is not homogeneous, thus leading to important temperature differences among the polymeric structure and to undesirable thermal gradients and stresses, also limiting the application fields of shape-memory polymers. In our present work we describe interesting activation alternatives, based on coating shape-memory polymers with different kinds of conductive materials, including textiles, conductive threads and conductive paint, which stand out for their easy, rapid and very cheap implementation. Distributed heating and homogeneous activation can be achieved in several of the alternatives studied and the technical results are comparable to those obtained by using advanced shape-memory nanocomposites, which have to deal with complex synthesis, processing and security aspects. Different combinations of shape memory epoxy resin with several coating electrotextiles, conductive films and paints are prepared, simulated with the help of thermal finite element method based resources and characterized using infrared thermography for validating the simulations and overall design process. A final application linked to an active catheter pincer is detailed and the advantages of using distributed heating instead of conventional resistors are discussed. PMID:28788401

Can modeling of HIV treatment processes improve outcomes? Capitalizing on an operations research approach to the global pandemic

PubMed Central

Xiong, Wei; Hupert, Nathaniel; Hollingsworth, Eric B; O'Brien, Megan E; Fast, Jessica; Rodriguez, William R

2008-01-01

Background Mathematical modeling has been applied to a range of policy-level decisions on resource allocation for HIV care and treatment. We describe the application of classic operations research (OR) techniques to address logistical and resource management challenges in HIV treatment scale-up activities in resource-limited countries. Methods We review and categorize several of the major logistical and operational problems encountered over the last decade in the global scale-up of HIV care and antiretroviral treatment for people with AIDS. While there are unique features of HIV care and treatment that pose significant challenges to effective modeling and service improvement, we identify several analogous OR-based solutions that have been developed in the service, industrial, and health sectors. Results HIV treatment scale-up includes many processes that are amenable to mathematical and simulation modeling, including forecasting future demand for services; locating and sizing facilities for maximal efficiency; and determining optimal staffing levels at clinical centers. Optimization of clinical and logistical processes through modeling may improve outcomes, but successful OR-based interventions will require contextualization of response strategies, including appreciation of both existing health care systems and limitations in local health workforces. Conclusion The modeling techniques developed in the engineering field of operations research have wide potential application to the variety of logistical problems encountered in HIV treatment scale-up in resource-limited settings. Increasing the number of cross-disciplinary collaborations between engineering and public health will help speed the appropriate development and application of these tools. PMID:18680594

Use of x-ray fluorescence for in-situ detection of metals

NASA Astrophysics Data System (ADS)

Elam, W. T. E.; Whitlock, Robert R.; Gilfrich, John V.

1995-01-01

X-ray fluorescence (XRF) is a well-established, non-destructive method of determining elemental concentrations at ppm levels in complex samples. It can operate in atmosphere with no sample preparation, and provides accuracies of 1% or better under optimum conditions. This report addresses two sets of issues concerning the use of x-ray fluorescence as a sensor technology for the cone penetrometer, for shipboard waste disposal, or for other in-situ, real- time environmental applications. The first issue concerns the applicability of XRF to these applications, and includes investigation of detection limits and matrix effects. We have evaluated the detection limits and quantitative accuracy of a sensor mock-up for metals in soils under conditions expected in the field. In addition, several novel ways of improving the lower limits of detection to reach the drinking water regulatory limits have been explored. The second issue is the engineering involved with constructing a spectrometer within the 1.75 inch diameter of the penetrometer pipe, which is the most rigorous physical constraint. Only small improvements over current state-of-the-art are required. Additional advantages of XRF are that no radioactive sources or hazardous materials are used in the sensor design, and no reagents or any possible sources of ignition are involved.

Attosecond-resolution Hong-Ou-Mandel interferometry.

PubMed

Lyons, Ashley; Knee, George C; Bolduc, Eliot; Roger, Thomas; Leach, Jonathan; Gauger, Erik M; Faccio, Daniele

2018-05-01

When two indistinguishable photons are each incident on separate input ports of a beamsplitter, they "bunch" deterministically, exiting via the same port as a direct consequence of their bosonic nature. This two-photon interference effect has long-held the potential for application in precision measurement of time delays, such as those induced by transparent specimens with unknown thickness profiles. However, the technique has never achieved resolutions significantly better than the few-femtosecond (micrometer) scale other than in a common-path geometry that severely limits applications. We develop the precision of Hong-Ou-Mandel interferometry toward the ultimate limits dictated by statistical estimation theory, achieving few-attosecond (or nanometer path length) scale resolutions in a dual-arm geometry, thus providing access to length scales pertinent to cell biology and monoatomic layer two-dimensional materials.

Spectromicroscopy and coherent diffraction imaging: focus on energy materials applications.

PubMed

Hitchcock, Adam P; Toney, Michael F

2014-09-01

Current and future capabilities of X-ray spectromicroscopy are discussed based on coherence-limited imaging methods which will benefit from the dramatic increase in brightness expected from a diffraction-limited storage ring (DLSR). The methods discussed include advanced coherent diffraction techniques and nanoprobe-based real-space imaging using Fresnel zone plates or other diffractive optics whose performance is affected by the degree of coherence. The capabilities of current systems, improvements which can be expected, and some of the important scientific themes which will be impacted are described, with focus on energy materials applications. Potential performance improvements of these techniques based on anticipated DLSR performance are estimated. Several examples of energy sciences research problems which are out of reach of current instrumentation, but which might be solved with the enhanced DLSR performance, are discussed.

Beyond CMB cosmic variance limits on reionization with the polarized Sunyaev-Zel'dovich effect

NASA Astrophysics Data System (ADS)

Meyers, Joel; Meerburg, P. Daniel; van Engelen, Alexander; Battaglia, Nicholas

2018-05-01

Upcoming cosmic microwave background (CMB) surveys will soon make the first detection of the polarized Sunyaev-Zel'dovich effect, the linear polarization generated by the scattering of CMB photons on the free electrons present in collapsed objects. Measurement of this polarization along with knowledge of the electron density of the objects allows a determination of the quadrupolar temperature anisotropy of the CMB as viewed from the space-time location of the objects. Maps of these remote temperature quadrupoles have several cosmological applications. Here we propose a new application: the reconstruction of the cosmological reionization history. We show that with quadrupole measurements out to redshift 3, constraints on the mean optical depth can be improved by an order of magnitude beyond the CMB cosmic variance limit.

Zonal methods for the parallel execution of range-limited N-body simulations

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

Bowers, Kevin J.; Dror, Ron O.; Shaw, David E.

2007-01-20

Particle simulations in fields ranging from biochemistry to astrophysics require the evaluation of interactions between all pairs of particles separated by less than some fixed interaction radius. The applicability of such simulations is often limited by the time required for calculation, but the use of massive parallelism to accelerate these computations is typically limited by inter-processor communication requirements. Recently, Snir [M. Snir, A note on N-body computations with cutoffs, Theor. Comput. Syst. 37 (2004) 295-318] and Shaw [D.E. Shaw, A fast, scalable method for the parallel evaluation of distance-limited pairwise particle interactions, J. Comput. Chem. 26 (2005) 1318-1328] independently introducedmore » two distinct methods that offer asymptotic reductions in the amount of data transferred between processors. In the present paper, we show that these schemes represent special cases of a more general class of methods, and introduce several new algorithms in this class that offer practical advantages over all previously described methods for a wide range of problem parameters. We also show that several of these algorithms approach an approximate lower bound on inter-processor data transfer.« less

The Influence of Power Limitations on Closed Environment Life Support System Applications

NASA Technical Reports Server (NTRS)

Flynn, Michael; Kliss, Mark (Technical Monitor)

1997-01-01

The future of manned space exploration will be determined through a process which balances the innate need of humanity to explore its surroundings and the costs associated with accomplishing these goals. For NASA, this balance is derived from economics and budgetary constraints that hold it accountable for the expenditure of public funds. These budgetary realities demand a reduction in cost and expenditures of exploration and research activities. For missions venturing out to the edge of habitability, the development of cost effective life support approaches will have a significant influence on mission viability. Over the past several years, a variety of mission scenarios for potential Lunar and Mars missions have been developed. The most promising of these scenarios attempt to provide basic mission requirements at a minimum cost. As a result, these scenarios are extremely power limited. For Closed Environment Life Support System (CELSS) applications, these realities impose both limitations and direction to future research. This paper presents a summary of these mission scenarios and an evaluation of the impact which these power limitations will have on CELSS system design.

Mechanomyographic Parameter Extraction Methods: An Appraisal for Clinical Applications

PubMed Central

Ibitoye, Morufu Olusola; Hamzaid, Nur Azah; Zuniga, Jorge M.; Hasnan, Nazirah; Wahab, Ahmad Khairi Abdul

2014-01-01

The research conducted in the last three decades has collectively demonstrated that the skeletal muscle performance can be alternatively assessed by mechanomyographic signal (MMG) parameters. Indices of muscle performance, not limited to force, power, work, endurance and the related physiological processes underlying muscle activities during contraction have been evaluated in the light of the signal features. As a non-stationary signal that reflects several distinctive patterns of muscle actions, the illustrations obtained from the literature support the reliability of MMG in the analysis of muscles under voluntary and stimulus evoked contractions. An appraisal of the standard practice including the measurement theories of the methods used to extract parameters of the signal is vital to the application of the signal during experimental and clinical practices, especially in areas where electromyograms are contraindicated or have limited application. As we highlight the underpinning technical guidelines and domains where each method is well-suited, the limitations of the methods are also presented to position the state of the art in MMG parameters extraction, thus providing the theoretical framework for improvement on the current practices to widen the opportunity for new insights and discoveries. Since the signal modality has not been widely deployed due partly to the limited information extractable from the signals when compared with other classical techniques used to assess muscle performance, this survey is particularly relevant to the projected future of MMG applications in the realm of musculoskeletal assessments and in the real time detection of muscle activity. PMID:25479326

Design considerations for a roll crusher/splitter for woody biomass

Treesearch

Donald L. Sirois; Colin Ashmore

1986-01-01

The principal focus of biomass harvesting in the past has been the use of chipping systems to reduce a wide variety of woody materials down to small pieces for easier handling and transporting. However, chipping systems have several short comings that limit their operational environments. For example, a conventional chipping system might not be applicable for...

Applications of satellite-derived disturbance information in support of sustainable forest management

Treesearch

Sean Healey; Warren Cohen; Gretchen Moisen

2007-01-01

The need for current information about the effects of fires, harvest, and storms is evident in many areas of sustainable forest management. While there are several potential sources of this information, each source has its limitations. Generally speaking, the statistical rigor associated with traditional forest sampling is an important asset in any monitoring effort....

26 CFR 1.415(a)-1 - General rules with respect to limitations on benefits and contributions under qualified plans.

Code of Federal Regulations, 2010 CFR

2010-04-01

... and disability benefits); (vii) Section 1.415(b)-1(g)(3) (regarding adjustments to applicable... survivor and disability benefits under governmental plans); (viii) Section 1.415(c)-1(b)(2)(ii) and (3)(iii...)(5) (providing an alternative rule for inclusion of compensation after a severance from employment...

Competitive Parallel Processing For Compression Of Data

NASA Technical Reports Server (NTRS)

Diner, Daniel B.; Fender, Antony R. H.

1990-01-01

Momentarily-best compression algorithm selected. Proposed competitive-parallel-processing system compresses data for transmission in channel of limited band-width. Likely application for compression lies in high-resolution, stereoscopic color-television broadcasting. Data from information-rich source like color-television camera compressed by several processors, each operating with different algorithm. Referee processor selects momentarily-best compressed output.

Sandbox CCDs

NASA Astrophysics Data System (ADS)

Janesick, James R.; Elliott, Tom S.; Winzenread, Rusty; Pinter, Jeff H.; Dyck, Rudolph H.

1995-04-01

Seven new CCDs are presented. The devices will be used in a variety of applications ranging from generating color cinema movies to adaptive optics camera systems to compensate for atmospheric turbulence at major astronomical observatories. This paper highlights areas of design, fabrication, and operation techniques to achieve state-of-the-art performance. We discuss current limitations of CCD technology for several key parameters.

Embedding Social Enterprise Approaches in the Operations of Public Higher Education Institutions: An Exploratory Case Study

ERIC Educational Resources Information Center

Mohammad, Esam Sohail

2017-01-01

In the second decade of the new century, America's public higher education institutions (PHEIs) face several key challenges: rising demands of accountability, a steady drop in public funding, and competition from virtual and for-profit entities. Limited research had been conducted on the applicability of social enterprise theory to these…

High power pulsed sources based on fiber amplifiers

NASA Astrophysics Data System (ADS)

Canat, Guillaume; Jaouën, Yves; Mollier, Jean-Claude; Bouzinac, Jean-Pierre; Cariou, Jean-Pierre

2017-11-01

Cladding-pumped rare-earth-doped fiber laser technologies are currently among the best sources for high power applications. Theses extremely compact and robust sources appoint them as good candidate for aeronautical and space applications. The double-clad (DC) fiber converts the poor beamquality of high-power large-area pump diodes from the 1st cladding to laser light at another wavelength guided in an active single-mode core. High-power coherent MOPA (Master Oscillator Power Amplifier) sources (several 10W CW or several 100W in pulsed regime) will soon be achieved. Unfortunately it also brings nonlinear effects which quickly impairs output signal distortions. Stimulated Brillouin scattering (SBS) and optical parametric amplification (OPA) have been shown to be strong limitations. Based on amplifier modeling and experiments we discuss the performances of these sources.

iCalm: wearable sensor and network architecture for wirelessly communicating and logging autonomic activity.

PubMed

Fletcher, Richard Ribon; Dobson, Kelly; Goodwin, Matthew S; Eydgahi, Hoda; Wilder-Smith, Oliver; Fernholz, David; Kuboyama, Yuta; Hedman, Elliott Bruce; Poh, Ming-Zher; Picard, Rosalind W

2010-03-01

Widespread use of affective sensing in healthcare applications has been limited due to several practical factors, such as lack of comfortable wearable sensors, lack of wireless standards, and lack of low-power affordable hardware. In this paper, we present a new low-cost, low-power wireless sensor platform implemented using the IEEE 802.15.4 wireless standard, and describe the design of compact wearable sensors for long-term measurement of electrodermal activity, temperature, motor activity, and photoplethysmography. We also illustrate the use of this new technology for continuous long-term monitoring of autonomic nervous system and motion data from active infants, children, and adults. We describe several new applications enabled by this system, discuss two specific wearable designs for the wrist and foot, and present sample data.

Recent advances in engineering microparticles and their nascent utilization in biomedical delivery and diagnostic applications.

PubMed

Choi, Andrew; Seo, Kyoung Duck; Kim, Do Wan; Kim, Bum Chang; Kim, Dong Sung

2017-02-14

Complex microparticles (MPs) bearing unique characteristics such as well-tailored sizes, various morphologies, and multi-compartments have been attempted to be produced by many researchers in the past decades. However, a conventionally used method of fabricating MPs, emulsion polymerization, has a limitation in achieving the aforementioned characteristics and several approaches such as the microfluidics-assisted (droplet-based microfluidics and flow lithography-based microfluidics), electrohydrodynamics (EHD)-based, centrifugation-based, and template-based methods have been recently suggested to overcome this limitation. The outstanding features of complex MPs engineered through these suggested methods have provided new opportunities for MPs to be applied in a wider range of applications including cell carriers, drug delivery agents, active pigments for display, microsensors, interface stabilizers, and catalyst substrates. Overall, the engineered MPs expose their potential particularly in the field of biomedical engineering as the increased complexity in the engineered MPs fulfills well the requirements of the high-end applications. This review outlines the current trends of newly developed techniques used for engineered MPs fabrication and focuses on the current state of engineered MPs in biomedical applications.

Application of adenylate energy charge to problems of environmental impact assessment in aquatic organisms

NASA Astrophysics Data System (ADS)

Ivanovici, A. M.

1980-03-01

Various physiological and biochemical methods have been proposed for assessing the effects of environmental perturbation on aquatic organisms. The success of these methods as diagnostic tools has, however, been limited. This paper proposes that adenylate energy charge overcomes some of these limitations. The adenylate energy charge (AEC) is calculated from concentrations of adenine nucleotides ([ATP+½ADP]/[ATP+ADP+AMP]), and is a reflection of metabolic potential available to an organism. Several features of this method are: correlation of specific values with physiological condition or growth state, a defined range of values, fast response times and high precision. Several examples from laboratory and field experiments are given to demonstrate these features. The test organisms used (mollusc species) were exposed to a variety of environmental perturbations, including salinity reduction, hydrocarbons and low doses of heavy metal. The studies performed indicate that the energy charge may be a useful measure in the assessment of environmental impact. Its use is restricted, however, as several limitations exist which need to be fully evaluated. Further work relating values to population characteristics of multicellular organisms needs to be completed before the method can become a predictive tool for management.

Capsule endoscopy: The road ahead

PubMed Central

Singeap, Ana-Maria; Stanciu, Carol; Trifan, Anca

2016-01-01

Since its introduction into clinical practice 15 years ago, capsule endoscopy (CE) has become the first-line investigation procedure in some small bowel pathologies, and more recently, dedicated esophageal and colon CE have expanded the fields of application to include the upper and lower gastrointestinal disorders. During this time, CE has become increasingly popular among gastroenterologists, with more than 2 million capsule examinations performed worldwide, and nearly 3000 PubMed-listed studies on its different aspects published. This huge interest in CE may be explained by its non-invasive nature, patient comfort, safety, and access to anatomical regions unattainable via conventional endoscopy. However, CE has several limitations which impede its wider clinical applications, including the lack of therapeutic capabilities, inability to obtain biopsies and control its locomotion. Several research groups are currently working to overcome these limitations, while novel devices able to control capsule movement, obtain high quality images, insufflate the gut lumen, perform chromoendoscopy, biopsy of suspect lesions, or even deliver targeted drugs directly to specific sites are under development. Overlooking current limitations, especially as some of them have already been successfully surmounted, and based on the tremendous progress in technology, it is expected that, by the end of next 15 years, CE able to perform both diagnostic and therapeutic procedures will remain the major form of digestive endoscopy. This review summarizes the literature that prognosticates about the future developments of CE. PMID:26755883

Perspectives on the application of nanotechnology in photodynamic therapy for the treatment of melanoma.

PubMed

Monge-Fuentes, Victoria; Muehlmann, Luis Alexandre; de Azevedo, Ricardo Bentes

2014-01-01

Malignant melanoma is the most aggressive form of skin cancer and has been traditionally considered difficult to treat. The worldwide incidence of melanoma has been increasing faster than any other type of cancer. Early detection, surgery, and adjuvant therapy enable improved outcomes; nonetheless, the prognosis of metastatic melanoma remains poor. Several therapies have been investigated for the treatment of melanoma; however, current treatment options for patients with metastatic disease are limited and non-curative in the majority of cases. Photodynamic therapy (PDT) has been proposed as a promising minimally invasive therapeutic procedure that employs three essential elements to induce cell death: a photosensitizer, light of a specific wavelength, and molecular oxygen. However, classical PDT has shown some drawbacks that limit its clinical application. In view of this, the use of nanotechnology has been considered since it provides many tools that can be applied to PDT to circumvent these limitations and bring new perspectives for the application of this therapy for different types of diseases. On that ground, this review focuses on the potential use of developing nanotechnologies able to bring significant benefits for anticancer PDT, aiming to reach higher efficacy and safety for patients with malignant melanoma.

Perspectives on the application of nanotechnology in photodynamic therapy for the treatment of melanoma

PubMed Central

Monge-Fuentes, Victoria; Muehlmann, Luis Alexandre; de Azevedo, Ricardo Bentes

2014-01-01

Malignant melanoma is the most aggressive form of skin cancer and has been traditionally considered difficult to treat. The worldwide incidence of melanoma has been increasing faster than any other type of cancer. Early detection, surgery, and adjuvant therapy enable improved outcomes; nonetheless, the prognosis of metastatic melanoma remains poor. Several therapies have been investigated for the treatment of melanoma; however, current treatment options for patients with metastatic disease are limited and non-curative in the majority of cases. Photodynamic therapy (PDT) has been proposed as a promising minimally invasive therapeutic procedure that employs three essential elements to induce cell death: a photosensitizer, light of a specific wavelength, and molecular oxygen. However, classical PDT has shown some drawbacks that limit its clinical application. In view of this, the use of nanotechnology has been considered since it provides many tools that can be applied to PDT to circumvent these limitations and bring new perspectives for the application of this therapy for different types of diseases. On that ground, this review focuses on the potential use of developing nanotechnologies able to bring significant benefits for anticancer PDT, aiming to reach higher efficacy and safety for patients with malignant melanoma. PMID:25317253

Elucidating the impact of micro-scale heterogeneous bacterial distribution on biodegradation

NASA Astrophysics Data System (ADS)

Schmidt, Susanne I.; Kreft, Jan-Ulrich; Mackay, Rae; Picioreanu, Cristian; Thullner, Martin

2018-06-01

Groundwater microorganisms hardly ever cover the solid matrix uniformly-instead they form micro-scale colonies. To which extent such colony formation limits the bioavailability and biodegradation of a substrate is poorly understood. We used a high-resolution numerical model of a single pore channel inhabited by bacterial colonies to simulate the transport and biodegradation of organic substrates. These high-resolution 2D simulation results were compared to 1D simulations that were based on effective rate laws for bioavailability-limited biodegradation. We (i) quantified the observed bioavailability limitations and (ii) evaluated the applicability of previously established effective rate concepts if microorganisms are heterogeneously distributed. Effective bioavailability reductions of up to more than one order of magnitude were observed, showing that the micro-scale aggregation of bacterial cells into colonies can severely restrict the bioavailability of a substrate and reduce in situ degradation rates. Effective rate laws proved applicable for upscaling when using the introduced effective colony sizes.

Noiseless coding for the Gamma Ray spectrometer

NASA Technical Reports Server (NTRS)

Rice, R.; Lee, J. J.

1985-01-01

The payload of several future unmanned space missions will include a sophisticated gamma ray spectrometer. Severely constrained data rates during certain portions of these missions could limit the possible science return from this instrument. This report investigates the application of universal noiseless coding techniques to represent gamma ray spectrometer data more efficiently without any loss in data integrity. Performance results demonstrate compression factors from 2.5:1 to 20:1 in comparison to a standard representation. Feasibility was also demonstrated by implementing a microprocessor breadboard coder/decoder using an Intel 8086 processor.

Application of augmented-Lagrangian methods in meteorology: Comparison of different conjugate-gradient codes for large-scale minimization

NASA Technical Reports Server (NTRS)

Navon, I. M.

1984-01-01

A Lagrange multiplier method using techniques developed by Bertsekas (1982) was applied to solving the problem of enforcing simultaneous conservation of the nonlinear integral invariants of the shallow water equations on a limited area domain. This application of nonlinear constrained optimization is of the large dimensional type and the conjugate gradient method was found to be the only computationally viable method for the unconstrained minimization. Several conjugate-gradient codes were tested and compared for increasing accuracy requirements. Robustness and computational efficiency were the principal criteria.

Applications of inertial-sensor high-inheritance instruments to DSN precision antenna pointing

NASA Technical Reports Server (NTRS)

Goddard, R. E.

1992-01-01

Laboratory test results of the initialization and tracking performance of an existing inertial-sensor-based instrument are given. The instrument, although not primarily designed for precision antenna pointing applications, demonstrated an on-average 10-hour tracking error of several millidegrees. The system-level instrument performance is shown by analysis to be sensor limited. Simulated instrument improvements show a tracking error of less than 1 mdeg, which would provide acceptable performance, i.e., low pointing loss, for the DSN 70-m antenna sub network, operating at Ka-band (1-cm wavelength).

Applications of inertial-sensor high-inheritance instruments to DSN precision antenna pointing

NASA Technical Reports Server (NTRS)

Goddard, R. E.

1992-01-01

Laboratory test results of the initialization and tracking performance of an existing inertial-sensor-based instrument are given. The instrument, although not primarily designed for precision antenna pointing applications, demonstrated an on-average 10-hour tracking error of several millidegrees. The system-level instrument performance is shown by analysis to be sensor limited. Simulated instrument improvements show a tracking error of less than 1 mdeg, which would provide acceptable performance, i.e., low pointing loss, for the Deep Space Network 70-m antenna subnetwork, operating at Ka-band (1-cm wavelength).

Application of scanning acoustic microscopy to advanced structural ceramics

NASA Technical Reports Server (NTRS)

Vary, Alex; Klima, Stanley J.

1987-01-01

A review is presentod of research investigations of several acoustic microscopy techniques for application to structural ceramics for advanced heat engines. Results obtained with scanning acoustic microscopy (SAM), scanning laser acoustic microscopy (SLAM), scanning electron acoustic microscopy (SEAM), and photoacoustic microscopy (PAM) are compared. The techniques were evaluated on research samples of green and sintered monolithic silicon nitrides and silicon carbides in the form of modulus-of-rupture bars containing deliberately introduced flaws. Strengths and limitations of the techniques are described with emphasis on statistics of detectability of flaws that constitute potential fracture origins.

Quasi-ideal dynamics of vortex solitons embedded in flattop nonlinear Bessel beams.

PubMed

Porras, Miguel A; Ramos, Francisco

2017-09-01

The applications of vortex solitons are severely limited by the diffraction and self-defocusing spreading of the background beam where they are nested. Nonlinear Bessel beams in self-defocusing media are nondiffracting, flattop beams where the nested vortex solitons can survive for propagation distances that are one order of magnitude larger than in the Gaussian or super-Gaussian beams. The dynamics of the vortex solitons is studied numerically and found to approach that in the ideal, uniform background, preventing vortex spiraling and decay, which eases vortex steering for applications.

Chemical denervation of the renal artery with vincristine for the treatment of resistant arterial hypertension: first-in-man application.

PubMed

Stefanadis, Christodoulos; Toutouzas, Konstantinos; Vlachopoulos, Charalambos; Tsioufis, Costas; Synetos, Andreas; Pietri, Panagiota; Tousoulis, Dimitris; Tsiamis, Eleftherios

2013-01-01

Renal artery denervation has recently emerged as a novel therapy for patients with resistant hypertension. Clinical results from renal sympathetic denervation support the safety and efficacy of this method over a period of 18 months. However, several limitations have been reported. Previous studies have shown that chemical denervation by vincristine is safe and effective in an experimental model. We describe the first-in-man application of chemical denervation with vincristine in a 74-year-old male patient with resistant arterial hypertension.

Applications of Fault Detection in Vibrating Structures

NASA Technical Reports Server (NTRS)

Eure, Kenneth W.; Hogge, Edward; Quach, Cuong C.; Vazquez, Sixto L.; Russell, Andrew; Hill, Boyd L.

2012-01-01

Structural fault detection and identification remains an area of active research. Solutions to fault detection and identification may be based on subtle changes in the time series history of vibration signals originating from various sensor locations throughout the structure. The purpose of this paper is to document the application of vibration based fault detection methods applied to several structures. Overall, this paper demonstrates the utility of vibration based methods for fault detection in a controlled laboratory setting and limitations of applying the same methods to a similar structure during flight on an experimental subscale aircraft.

Applications of TIMS data in agricultural areas and related atmospheric considerations

NASA Technical Reports Server (NTRS)

Pelletier, R. E.; Ochoa, M. C.

1986-01-01

While much of traditional remote sensing in agricultural research was limited to the visible and reflective infrared, advances in thermal infrared remote sensing technology are adding a dimension to digital image analysis of agricultural areas. The Thermal Infrared Multispectral Scanner (TIMS) an airborne sensor having six bands over the nominal 8.2 to 12.2 m range, offers the ability to calculate land surface emissivities unlike most previous singular broadband sensors. Preliminary findings on the utility of the TIMS for several agricultural applications and related atmospheric considerations are discussed.

Research on combustion instability and application to solid propellant rocket motors. II.

NASA Technical Reports Server (NTRS)

Culick, F. E. C.

1972-01-01

Review of the current state of analyses of combustion instability in solid-propellant rocket motors, citing appropriate measurements and observations. The work discussed has become increasingly important, both for the interpretation of laboratory data and for predicting the transient behavior of disturbances in full-scale motors. Two central questions are considered - namely, linear stability and nonlinear behavior. Several classes of problems are discussed as special cases of a general approach to the analysis of combustion instability. Application to motors, and particularly the limitations presently understood, are stressed.

Injectable Hydrogels for Cardiac Tissue Repair after Myocardial Infarction

PubMed Central

Khattab, Ahmad; Islam, Mohammad Ariful; Hweij, Khaled Abou; Zeitouny, Joya; Waters, Renae; Sayegh, Malek; Hossain, Md Monowar; Paul, Arghya

2015-01-01

Cardiac tissue damage due to myocardial infarction (MI) is one of the leading causes of mortality worldwide. The available treatments of MI include pharmaceutical therapy, medical device implants, and organ transplants, all of which have severe limitations including high invasiveness, scarcity of donor organs, thrombosis or stenosis of devices, immune rejection, and prolonged hospitalization time. Injectable hydrogels have emerged as a promising solution for in situ cardiac tissue repair in infarcted hearts after MI. In this review, an overview of various natural and synthetic hydrogels for potential application as injectable hydrogels in cardiac tissue repair and regeneration is presented. The review starts with brief discussions about the pathology of MI, its current clinical treatments and their limitations, and the emergence of injectable hydrogels as a potential solution for post MI cardiac regeneration. It then summarizes various hydrogels, their compositions, structures and properties for potential application in post MI cardiac repair, and recent advancements in the application of injectable hydrogels in treatment of MI. Finally, the current challenges associated with the clinical application of injectable hydrogels to MI and their potential solutions are discussed to help guide the future research on injectable hydrogels for translational therapeutic applications in regeneration of cardiac tissue after MI. PMID:27668147

A response to: Limitations within "The Limits to Tree Height".

PubMed

Koch, George W; Sillett, Stephen C

2009-02-01

Here we respond to the communication in American Journal of Botany (96: 542-544 in this issue) by Netting, who proposes several ways in which our paper "The Limits to Tree Height" (Nature 428: 851-854) may have erred in estimating the biophysical limits to height growth in Sequoia sempervirens. We first explain that because embolism repair requires long time periods and is generally incomplete, xylem vulnerability characteristics offer a sound basis for estimating performance limits in woody plants. We reaffirm our earlier use of vertical gradients of foliar carbon isotope composition with new data for S. sempervirens. We support these arguments with reference to studies in other tree species. We take exception with Netting's view that the turgor pressure-cell expansion relationship for Zea mays is applicable to S. sempervirens. Finally, we second Netting's call for more work on carbon allocation vis a vis height growth limits.

Force Limited Vibration Testing Monograph

NASA Technical Reports Server (NTRS)

Scharton, Terry D.

1997-01-01

The practice of limiting the shaker force in vibration tests was investigated at the NASA Jet Propulsion Laboratory (JPL) in 1990 after the mechanical failure of an aerospace component during a vibration test. Now force limiting is used in almost every major vibration test at JPL and in many vibration tests at NASA Goddard Space Flight Center (GSFC) and at many aerospace contractors. The basic ideas behind force limiting have been in the literature for several decades, but the piezo-electric force transducers necessary to conveniently implement force limiting have been available only in the last decade. In 1993, funding was obtained from the NASA headquarters Office of Chief Engineer to develop and document the technology needed to establish force limited vibration testing as a standard approach available to all NASA centers and aerospace contractors. This monograph is the final report on that effort and discusses the history, theory, and applications of the method in some detail.

Physics issues in diffraction limited storage ring design

NASA Astrophysics Data System (ADS)

Fan, Wei; Bai, ZhengHe; Gao, WeiWei; Feng, GuangYao; Li, WeiMin; Wang, Lin; He, DuoHui

2012-05-01

Diffraction limited electron storage ring is considered a promising candidate for future light sources, whose main characteristics are higher brilliance, better transverse coherence and better stability. The challenge of diffraction limited storage ring design is how to achieve the ultra low beam emittance with acceptable nonlinear performance. Effective linear and nonlinear parameter optimization methods based on Artificial Intelligence were developed for the storage ring physical design. As an example of application, partial physical design of HALS (Hefei Advanced Light Source), which is a diffraction limited VUV and soft X-ray light source, was introduced. Severe emittance growth due to the Intra Beam Scattering effect, which is the main obstacle to achieve ultra low emittance, was estimated quantitatively and possible cures were discussed. It is inspiring that better performance of diffraction limited storage ring can be achieved in principle with careful parameter optimization.

LSPV+7, a branch-point-tolerant reconstructor for strong turbulence adaptive optics.

PubMed

Steinbock, Michael J; Hyde, Milo W; Schmidt, Jason D

2014-06-20

Optical wave propagation through long paths of extended turbulence presents unique challenges to adaptive optics (AO) systems. As scintillation and branch points develop in the beacon phase, challenges arise in accurately unwrapping the received wavefront and optimizing the reconstructed phase with respect to branch cut placement on a continuous facesheet deformable mirror. Several applications are currently restricted by these capability limits: laser communication, laser weapons, remote sensing, and ground-based astronomy. This paper presents a set of temporally evolving AO simulations comparing traditional least-squares reconstruction techniques to a complex-exponential reconstructor and several other reconstructors derived from the postprocessing congruence operation. The reconstructors' behavior in closed-loop operation is compared and discussed, providing several insights into the fundamental strengths and limitations of each reconstructor type. This research utilizes a self-referencing interferometer (SRI) as the high-order wavefront sensor, driving a traditional linear control law in conjunction with a cooperative point source beacon. The SRI model includes practical optical considerations and frame-by-frame fiber coupling effects to allow for realistic noise modeling. The "LSPV+7" reconstructor is shown to offer the best performance in terms of Strehl ratio and correction stability-outperforming the traditional least-squares reconstructed system by an average of 120% in the studied scenarios. Utilizing a continuous facesheet deformable mirror, these reconstructors offer significant AO performance improvements in strong turbulence applications without the need for segmented deformable mirrors.

Amplitude-integrated EEG and the newborn infant.

PubMed

Shah, Divyen K; Mathur, Amit

2014-01-01

There is emerging recognition of the need for continuous long term electrographic monitoring of the encephalopathic neonate. While full-montage EEG with video remains the gold standard for monitoring, it is limited in application due to the complexity of lead application and specialized interpretation of results. Amplitude integrated EEG (aEEG) is derived from limited channels (usually C3-P3, C4-P4) and is filtered, rectified and time-compressed to serve as a bedside electrographic trend monitor. Its simple application and interpretation has resulted in increasing use in neonatal units across the world. Validation studies with full montage EEG have shown reliable results in interpretation of EEG background and electrographic seizures, especially when used with the simultaneously displayed raw EEG trace. Several aEEG monitors are commercially available and seizure algorithms are being developed for use on these monitors. These aEEG monitors, complement conventional EEG and offer a significant advance in the feasibility of long term electrographic monitoring of the encephalopathic neonate.

Constructing, connecting and soldering nanostructures by environmental electron beam deposition

NASA Astrophysics Data System (ADS)

Mølhave, Kristian; Nørgaard Madsen, Dorte; Dohn, Søren; Bøggild, Peter

2004-08-01

Highly conductive nanoscale deposits with solid gold cores can be made by electron beam deposition in an environmental scanning electron microscope (ESEM), suggesting the method to be used for constructing, connecting and soldering nanostructures. This paper presents a feasibility study for such applications. We identify several issues related to contamination and unwanted deposition, relevant for deposition in both vacuum (EBD) and environmental conditions (EEBD). We study relations between scan rate, deposition rate, angle and line width for three-dimensional structures. Furthermore, we measure the conductivity of deposits containing gold cores, and find these structures to be highly conductive, approaching the conductivity of solid gold and capable of carrying high current densities. Finally, we study the use of the technique for soldering nanostructures such as carbon nanotubes. Based on the presented results we are able to estimate limits for the applicability of the method for the various applications, but also demonstrate that it is a versatile and powerful tool for nanotechnology within these limits.

Signal processing and calibration procedures for in situ diode-laser absorption spectroscopy.

PubMed

Werle, P W; Mazzinghi, P; D'Amato, F; De Rosa, M; Maurer, K; Slemr, F

2004-07-01

Gas analyzers based on tunable diode-laser spectroscopy (TDLS) provide high sensitivity, fast response and highly specific in situ measurements of several atmospheric trace gases simultaneously. Under optimum conditions even a shot noise limited performance can be obtained. For field applications outside the laboratory practical limitations are important. At ambient mixing ratios below a few parts-per-billion spectrometers become more and more sensitive towards noise, interference, drift effects and background changes associated with low level signals. It is the purpose of this review to address some of the problems which are encountered at these low levels and to describe a signal processing strategy for trace gas monitoring and a concept for in situ system calibration applicable for tunable diode-laser spectroscopy. To meet the requirement of quality assurance for field measurements and monitoring applications, procedures to check the linearity according to International Standard Organization regulations are described and some measurements of calibration functions are presented and discussed.

Thermodynamics of Yukawa fluids near the one-component-plasma limit

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

Khrapak, Sergey A.; Aix-Marseille-Université, CNRS, Laboratoire PIIM, UMR 7345, 13397 Marseille Cedex 20; Semenov, Igor L.

Thermodynamics of weakly screened (near the one-component-plasma limit) Yukawa fluids in two and three dimensions is analyzed in detail. It is shown that the thermal component of the excess internal energy of these fluids, when expressed in terms of the properly normalized coupling strength, exhibits the scaling pertinent to the corresponding one-component-plasma limit (the scalings differ considerably between the two- and three-dimensional situations). This provides us with a simple and accurate practical tool to estimate thermodynamic properties of weakly screened Yukawa fluids. Particular attention is paid to the two-dimensional fluids, for which several important thermodynamic quantities are calculated to illustratemore » the application of the approach.« less

Fipronil application on rice paddy fields reduces densities of common skimmer and scarlet skimmer

PubMed Central

Kasai, Atsushi; Hayashi, Takehiko I.; Ohnishi, Hitoshi; Suzuki, Kazutaka; Hayasaka, Daisuke; Goka, Koichi

2016-01-01

Several reports suggested that rice seedling nursery-box application of some systemic insecticides (neonicotinoids and fipronil) is the cause of the decline in dragonfly species noted since the 1990s in Japan. We conducted paddy mesocosm experiments to investigate the effect of the systemic insecticides clothianidin, fipronil and chlorantraniliprole on rice paddy field biological communities. Concentrations of all insecticides in the paddy water were reduced to the limit of detection within 3 months after application. However, residuals of these insecticides in the paddy soil were detected throughout the experimental period. Plankton species were affected by clothianidin and chlorantraniliprole right after the applications, but they recovered after the concentrations decreased. On the other hand, the effects of fipronil treatment, especially on Odonata, were larger than those of any other treatment. The number of adult dragonflies completing eclosion was severely decreased in the fipronil treatment. These results suggest that the accumulation of these insecticides in paddy soil reduces biodiversity by eliminating dragonfly nymphs, which occupy a high trophic level in paddy fields. PMID:26979488

Spectral Band Selection for Urban Material Classification Using Hyperspectral Libraries

NASA Astrophysics Data System (ADS)

Le Bris, A.; Chehata, N.; Briottet, X.; Paparoditis, N.

2016-06-01

In urban areas, information concerning very high resolution land cover and especially material maps are necessary for several city modelling or monitoring applications. That is to say, knowledge concerning the roofing materials or the different kinds of ground areas is required. Airborne remote sensing techniques appear to be convenient for providing such information at a large scale. However, results obtained using most traditional processing methods based on usual red-green-blue-near infrared multispectral images remain limited for such applications. A possible way to improve classification results is to enhance the imagery spectral resolution using superspectral or hyperspectral sensors. In this study, it is intended to design a superspectral sensor dedicated to urban materials classification and this work particularly focused on the selection of the optimal spectral band subsets for such sensor. First, reflectance spectral signatures of urban materials were collected from 7 spectral libraires. Then, spectral optimization was performed using this data set. The band selection workflow included two steps, optimising first the number of spectral bands using an incremental method and then examining several possible optimised band subsets using a stochastic algorithm. The same wrapper relevance criterion relying on a confidence measure of Random Forests classifier was used at both steps. To cope with the limited number of available spectra for several classes, additional synthetic spectra were generated from the collection of reference spectra: intra-class variability was simulated by multiplying reference spectra by a random coefficient. At the end, selected band subsets were evaluated considering the classification quality reached using a rbf svm classifier. It was confirmed that a limited band subset was sufficient to classify common urban materials. The important contribution of bands from the Short Wave Infra-Red (SWIR) spectral domain (1000-2400 nm) to material classification was also shown.

Treatment of gastro-esophageal reflux disease: the new kids to block.

PubMed

Blondeau, K

2010-08-01

Refractory gastro-esophageal reflux disease (GERD), defined as persistent symptoms despite proton pump inhibitor (PPI) therapy, is an increasingly prevalent condition and is becoming a major challenge for the clinician. Since non-acidic reflux may be associated with symptoms persisting during PPI treatment, the lower esophageal sphincter (LES), the most important barrier protecting against reflux, has become an important target for the treatment of (refractory) GERD. Preclinical research has identified several receptors that are involved in the control of transient lower esophageal sphincter relaxations (TLESRs), the predominant mechanism of both acid and non-acidic reflux events, and several drugs have now been tested in humans. The GABA(B) agonist baclofen has demonstrated to effectively reduce the rate of TLESRs and the amount of reflux in both GERD patients and healthy volunteers. Nevertheless, the occurrence of central side effects limits its clinical use for the treatment of GERD. Several analogues are being developed to overcome this limitation and have shown promising results. Additionally, metabotropic glutamate receptor 5 (mGluR5) receptor antagonists have shown to reduce both acid and non-acidic reflux in GERD patients and several molecules are currently being evaluated. Although CB(1) antagonists have been shown to reduce TLESRs, they are also associated with central side effects, limiting their clinical applicability. Despite the identification of several potentially interesting drugs, the main challenge for the future remains the reduction of central side effects. Moreover, future studies will need to demonstrate the efficacy of these treatments in patients with refractory GERD.

Trade-off Analysis of Underwater Acoustic Sensor Networks

NASA Astrophysics Data System (ADS)

Tuna, G.; Das, R.

2017-09-01

In the last couple of decades, Underwater Acoustic Sensor Networks (UASNs) were started to be used for various commercial and non-commercial purposes. However, in underwater environments, there are some specific inherent constraints, such as high bit error rate, variable and large propagation delay, limited bandwidth capacity, and short-range communications, which severely degrade the performance of UASNs and limit the lifetime of underwater sensor nodes as well. Therefore, proving reliability of UASN applications poses a challenge. In this study, we try to balance energy consumption of underwater acoustic sensor networks and minimize end-to-end delay using an efficient node placement strategy. Our simulation results reveal that if the number of hops is reduced, energy consumption can be reduced. However, this increases end-to-end delay. Hence, application-specific requirements must be taken into consideration when determining a strategy for node deployment.

NASA Space Laser Technology

NASA Technical Reports Server (NTRS)

Krainak, Michael A.

2015-01-01

Over the next two decades, the number of space based laser missions for mapping, spectroscopy, remote sensing and other scientific investigations will increase several fold. The demand for high wall-plug efficiency, low noise, narrow linewidth laser systems to meet different systems requirements that can reliably operate over the life of a mission will be high. The general trends will be for spatial quality very close to the diffraction limit, improved spectral performance, increased wall-plug efficiency and multi-beam processing. Improved spectral performance will include narrower spectral width (very near the transform limit), increased wavelength stability and or tuning (depending on application) and lasers reaching a wider range of wavelengths stretching into the mid-infrared and the near ultraviolet. We are actively developing high efficiency laser transmitter and high-sensitivity laser receiver systems that are suitable for spaceborne applications.

A synthesis of biomass utilization for bioenergy production in the Western United States.

Treesearch

David L. Nicholls; Robert A. Monserud; Dennis P. Dykstra

2008-01-01

We examine the use of woody residues, primarily from forest harvesting or wood products manufacturing operations (and to a limited degree from urban wood wastes), as a feedstock for direct-combustion bioenergy systems for electrical or thermal power applications. We examine opportunities for utilizing biomass for energy at several scales, with an emphasis on larger...

Twenty Things to Do With a Computer. Artificial Intelligence Memo Number 248.

ERIC Educational Resources Information Center

Papert, Seymour; Solomon, Cynthia

Ideas about computers in education are usually limited to transactions of a conversational form between students and machines. Computers, however, can do many other things and it is only inertia and prejudice, not lack of ideas, which stand in the way of broadening the range of computer applications in schools. Several examples, over half of which…

Frequency Division Multiplexing of Interferometric Sensor Arrays

DTIC Science & Technology

1989-05-03

exception to this is the approach which employs Fabry - Perot sensorsg 10,12 in which higher order reflections will result inmoderately severe crosstalk...The Fabry - Perot technique appears to have limited array applications because of this problem. Although frequency division multiplexing has received...interferometers (- 4 cm path difference) and phase generated carrier demultiplexing demodulation . This approach leads to a simple all-passive sensor

Stocking levels and underlying assumptions for uneven-aged Ponderosa Pine stands.

Treesearch

P.H. Cochran

1992-01-01

Potential Problems With Q-Values Many ponderosa pine stands have a limited number of size classes, and it may be desirable to carry very large trees through several cutting cycles. Large numbers of trees below commercial size are not needed to provide adequate numbers of future replacement trees. Under these conditions, application of stand density index (SDI) can have...

Green synthesis of highly crystalline and visible-light sensitive C-, N- and S- codoped with Ag TiO2 nanocatalyst

EPA Science Inventory

Titanium dioxide (TiO2) has been a focus of attention as chemically stable, relatively nontoxic, inexpensive and highly efficient photocatalyst applicable for a wide array of uses. However, main disadvantage that severely limits its wider use is the large band gap, 3.0 eV and 3.2...

Monitoring Bloom Dynamics of a Common Coastal Bioluminescent Ctenophore

DTIC Science & Technology

2009-09-30

potential in the coastal zone environment. OBJECTIVES Blooms of bioluminescent jellyfish , especially of Mnemiopsis leidyi, are a common occurrence... jellyfish populations are done with net collections by hand at stations weekly, monthly, or seasonally. These time scales severely limit our knowledge...the collection of both biotic and abiotic data continuously. 5 IMPACT/APPLICATIONS As incidents of jellyfish blooms, especially Mnemiopsis

Aerogel Development

NASA Technical Reports Server (NTRS)

Sahai, Rashmi K.

2005-01-01

Aerogel is one of the most promising materials of the future. It's unique properties, including high porosity, transparency, very high thermal tolerance, and environmental friendliness give it the potential of replacing many different products used in society today. However, the market for aerogel is still very limited because of the cost of producing the material and its fragility. The principle objective of my project has been to find new ways to apply aerogel in order to increase its practicality and appeal to different aspects of society. More specifically, I have focused on finding different chemicals that will coat aerogel and increase its durability. Because aerogel is so fragile and will crumble under the pressure of most coatings this has been no easy task. However, by experimenting with many different coatings and combinations of aerogel properties, I have made several significant discoveries. Aerogel (ideally, high density and hydrophobic) can be coated with several acrylic polymers, including artist's gel and nail polish. These materials provide a protective layering around the aerogel and keep it from breaking as easily. Because fragility is one of the main reasons applications of aerogel are limited, these discoveries will hopefully aid in finding future applications for this extraordinary material.

Biomaterials in Cardiovascular Research: Applications and Clinical Implications

PubMed Central

Jaganathan, Saravana Kumar; Supriyanto, Eko; Murugesan, Selvakumar; Balaji, Arunpandian; Asokan, Manjeesh Kumar

2014-01-01

Cardiovascular biomaterials (CB) dominate the category of biomaterials based on the demand and investments in this field. This review article classifies the CB into three major classes, namely, metals, polymers, and biological materials and collates the information about the CB. Blood compatibility is one of the major criteria which limit the use of biomaterials for cardiovascular application. Several key players are associated with blood compatibility and they are discussed in this paper. To enhance the compatibility of the CB, several surface modification strategies were in use currently. Some recent applications of surface modification technology on the materials for cardiovascular devices were also discussed for better understanding. Finally, the current trend of the CB, endothelization of the cardiac implants and utilization of induced human pluripotent stem cells (ihPSCs), is also presented in this review. The field of CB is growing constantly and many new investigators and researchers are developing interest in this domain. This review will serve as a one stop arrangement to quickly grasp the basic research in the field of CB. PMID:24895577

Recent Advances of Light-Mediated Theranostics

PubMed Central

Ai, Xiangzhao; Mu, Jing; Xing, Bengang

2016-01-01

Currently, precision theranostics have been extensively demanded for the effective treatment of various human diseases. Currently, efficient therapy at the targeted disease areas still remains challenging since most available drug molecules lack of selectivity to the pathological sites. Among different approaches, light-mediated therapeutic strategy has recently emerged as a promising and powerful tool to precisely control the activation of therapeutic reagents and imaging probes in vitro and in vivo, mostly attributed to its unique properties including minimally invasive capability and highly spatiotemporal resolution. Although it has achieved initial success, the conventional strategies for light-mediated theranostics are mostly based on the light with short wavelength (e.g., UV or visible light), which may usually suffer from several undesired drawbacks, such as limited tissue penetration depth, unavoidable light absorption/scattering and potential phototoxicity to healthy tissues, etc. Therefore, a near-infrared (NIR) light-mediated approach on the basis of long-wavelength light (700-1000 nm) irradiation, which displays deep-tissue penetration, minimized photo-damage and low autofluoresence in living systems, has been proposed as an inspiring alternative for precisely phototherapeutic applications in the last decades. Despite numerous NIR light-responsive molecules have been currently proposed for clinical applications, several inherent drawbacks, such as troublesome synthetic procedures, low water solubility and limited accumulation abilities in targeted areas, heavily restrict their applications in deep-tissue therapeutic and imaging studies. Thanks to the amazing properties of several nanomaterials with large extinction coefficient in the NIR region, the construction of NIR light responsive nanoplatforms with multifunctions have become promising approaches for deep-seated diseases diagnosis and therapy. In this review, we summarized various light-triggered theranostic strategies and introduced their great advances in biomedical applications in recent years. Moreover, some other promising light-assisted techniques, such as photoacoustic and Cerenkov radiation, were also systemically discussed. Finally, the potential challenges and future perspectives for light-mediated deep-tissue diagnosis and therapeutics were proposed. PMID:27877246

Detection methods and performance criteria for genetically modified organisms.

PubMed

Bertheau, Yves; Diolez, Annick; Kobilinsky, André; Magin, Kimberly

2002-01-01

Detection methods for genetically modified organisms (GMOs) are necessary for many applications, from seed purity assessment to compliance of food labeling in several countries. Numerous analytical methods are currently used or under development to support these needs. The currently used methods are bioassays and protein- and DNA-based detection protocols. To avoid discrepancy of results between such largely different methods and, for instance, the potential resulting legal actions, compatibility of the methods is urgently needed. Performance criteria of methods allow evaluation against a common standard. The more-common performance criteria for detection methods are precision, accuracy, sensitivity, and specificity, which together specifically address other terms used to describe the performance of a method, such as applicability, selectivity, calibration, trueness, precision, recovery, operating range, limit of quantitation, limit of detection, and ruggedness. Performance criteria should provide objective tools to accept or reject specific methods, to validate them, to ensure compatibility between validated methods, and be used on a routine basis to reject data outside an acceptable range of variability. When selecting a method of detection, it is also important to consider its applicability, its field of applications, and its limitations, by including factors such as its ability to detect the target analyte in a given matrix, the duration of the analyses, its cost effectiveness, and the necessary sample sizes for testing. Thus, the current GMO detection methods should be evaluated against a common set of performance criteria.

Hybrid cloud and cluster computing paradigms for life science applications

PubMed Central

2010-01-01

Background Clouds and MapReduce have shown themselves to be a broadly useful approach to scientific computing especially for parallel data intensive applications. However they have limited applicability to some areas such as data mining because MapReduce has poor performance on problems with an iterative structure present in the linear algebra that underlies much data analysis. Such problems can be run efficiently on clusters using MPI leading to a hybrid cloud and cluster environment. This motivates the design and implementation of an open source Iterative MapReduce system Twister. Results Comparisons of Amazon, Azure, and traditional Linux and Windows environments on common applications have shown encouraging performance and usability comparisons in several important non iterative cases. These are linked to MPI applications for final stages of the data analysis. Further we have released the open source Twister Iterative MapReduce and benchmarked it against basic MapReduce (Hadoop) and MPI in information retrieval and life sciences applications. Conclusions The hybrid cloud (MapReduce) and cluster (MPI) approach offers an attractive production environment while Twister promises a uniform programming environment for many Life Sciences applications. Methods We used commercial clouds Amazon and Azure and the NSF resource FutureGrid to perform detailed comparisons and evaluations of different approaches to data intensive computing. Several applications were developed in MPI, MapReduce and Twister in these different environments. PMID:21210982

Hybrid cloud and cluster computing paradigms for life science applications.

PubMed

Qiu, Judy; Ekanayake, Jaliya; Gunarathne, Thilina; Choi, Jong Youl; Bae, Seung-Hee; Li, Hui; Zhang, Bingjing; Wu, Tak-Lon; Ruan, Yang; Ekanayake, Saliya; Hughes, Adam; Fox, Geoffrey

2010-12-21

Clouds and MapReduce have shown themselves to be a broadly useful approach to scientific computing especially for parallel data intensive applications. However they have limited applicability to some areas such as data mining because MapReduce has poor performance on problems with an iterative structure present in the linear algebra that underlies much data analysis. Such problems can be run efficiently on clusters using MPI leading to a hybrid cloud and cluster environment. This motivates the design and implementation of an open source Iterative MapReduce system Twister. Comparisons of Amazon, Azure, and traditional Linux and Windows environments on common applications have shown encouraging performance and usability comparisons in several important non iterative cases. These are linked to MPI applications for final stages of the data analysis. Further we have released the open source Twister Iterative MapReduce and benchmarked it against basic MapReduce (Hadoop) and MPI in information retrieval and life sciences applications. The hybrid cloud (MapReduce) and cluster (MPI) approach offers an attractive production environment while Twister promises a uniform programming environment for many Life Sciences applications. We used commercial clouds Amazon and Azure and the NSF resource FutureGrid to perform detailed comparisons and evaluations of different approaches to data intensive computing. Several applications were developed in MPI, MapReduce and Twister in these different environments.

Algorithms for Lightweight Key Exchange.

PubMed

Alvarez, Rafael; Caballero-Gil, Cándido; Santonja, Juan; Zamora, Antonio

2017-06-27

Public-key cryptography is too slow for general purpose encryption, with most applications limiting its use as much as possible. Some secure protocols, especially those that enable forward secrecy, make a much heavier use of public-key cryptography, increasing the demand for lightweight cryptosystems that can be implemented in low powered or mobile devices. This performance requirements are even more significant in critical infrastructure and emergency scenarios where peer-to-peer networks are deployed for increased availability and resiliency. We benchmark several public-key key-exchange algorithms, determining those that are better for the requirements of critical infrastructure and emergency applications and propose a security framework based on these algorithms and study its application to decentralized node or sensor networks.

Review of advanced catheter technologies in radiation oncology brachytherapy procedures

PubMed Central

Zhou, Jun; Zamdborg, Leonid; Sebastian, Evelyn

2015-01-01

The development of new catheter and applicator technologies in recent years has significantly improved treatment accuracy, efficiency, and outcomes in brachytherapy. In this paper, we review these advances, focusing on the performance of catheter imaging and reconstruction techniques in brachytherapy procedures using magnetic resonance images and electromagnetic tracking. The accuracy of catheter reconstruction, imaging artifacts, and other notable properties of plastic and titanium applicators in gynecologic treatments are reviewed. The accuracy, noise performance, and limitations of electromagnetic tracking for catheter reconstruction are discussed. Several newly developed applicators for accelerated partial breast irradiation and gynecologic treatments are also reviewed. New hypofractionated high dose rate treatment schemes in prostate cancer and accelerated partial breast irradiation are presented. PMID:26203277

Biocompatible Quantum Dots for Biological Applications

PubMed Central

Rosenthal, Sandra J.; Chang, Jerry C.; Kovtun, Oleg; McBride, James R.; Tomlinson, Ian D.

2011-01-01

Semiconductor quantum dots are quickly becoming a critical diagnostic tool for discerning cellular function at the molecular level. Their high brightness, long-lasting, sizetunable, and narrow luminescence set them apart from conventional fluorescence dyes. Quantum dots are being developed for a variety of biologically oriented applications, including fluorescent assays for drug discovery, disease detection, single protein tracking, and intracellular reporting. This review introduces the science behind quantum dots and describes how they are made biologically compatible. Several applications are also included, illustrating strategies toward target specificity, and are followed by a discussion on the limitations of quantum dot approaches. The article is concluded with a look at the future direction of quantum dots. PMID:21276935

Quantum technology and its applications

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

Boshier, Malcolm; Berkeland, Dana; Govindan, Tr

Quantum states of matter can be exploited as high performance sensors for measuring time, gravity, rotation, and electromagnetic fields, and quantum states of light provide powerful new tools for imaging and communication. Much attention is being paid to the ultimate limits of this quantum technology. For example, it has already been shown that exotic quantum states can be used to measure or image with higher precision or higher resolution or lower radiated power than any conventional technologies, and proof-of-principle experiments demonstrating measurement precision below the standard quantum limit (shot noise) are just starting to appear. However, quantum technologies have anothermore » powerful advantage beyond pure sensing performance that may turn out to be more important in practical applications: the potential for building devices with lower size/weight/power (SWaP) and cost requirements than existing instruments. The organizers of Quantum Technology Applications Workshop (QTAW) have several goals: (1) Bring together sponsors, researchers, engineers and end users to help build a stronger quantum technology community; (2) Identify how quantum systems might improve the performance of practical devices in the near- to mid-term; and (3) Identify applications for which more long term investment is necessary to realize improved performance for realistic applications. To realize these goals, the QTAW II workshop included fifty scientists, engineers, managers and sponsors from academia, national laboratories, government and the private-sector. The agenda included twelve presentations, a panel discussion, several breaks for informal exchanges, and a written survey of participants. Topics included photon sources, optics and detectors, squeezed light, matter waves, atomic clocks and atom magnetometry. Corresponding applications included communication, imaging, optical interferometry, navigation, gravimetry, geodesy, biomagnetism, and explosives detection. Participants considered the physics and engineering of quantum and conventional technologies, and how quantum techniques could (or could not) overcome limitations of conventional systems. They identified several auxiliary technologies that needed to be further developed in order to make quantum technology more accessible. Much of the discussion also focused on specific applications of quantum technology and how to push the technology into broader communities, which would in turn identify new uses of the technology. Since our main interest is practical improvement of devices and techniques, we take a liberal definition of 'quantum technology': a system that utilizes preparation and measurement of a well-defined coherent quantum state. This nomenclature encompasses features broader than entanglement, squeezing or quantum correlations, which are often more difficult to utilize outside of a laboratory environment. Still, some applications discussed in the workshop do take advantage of these 'quantum-enhanced' features. They build on the more established quantum technologies that are amenable to manipulation at the quantum level, such as atom magnetometers and atomic clocks. Understanding and developing those technologies through traditional engineering will clarify where quantum-enhanced features can be used most effectively, in addition to providing end users with improved devices in the near-term.« less

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. These approaches are 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 the inverse design of a turbine airfoil. The efficiency improvements achieved by the different approaches are evaluated and compared.

Application of LANDSAT-2 data to the implementation and enforcement of the Pennsylvania Surface Mining Conservation and Reclamation Act

NASA Technical Reports Server (NTRS)

Russell, O. R. (Principal Investigator); Nichols, D. A.; Anderson, R.

1977-01-01

The author has identified the following significant results. Evaluation of LANDSAT imagery indicates severe limitations in its utility for surface mine land studies. Image stripping resulting from unequal detector response on satellite degrades the image quality to the extent that images of scales larger than 1:125,000 are of limited value for manual interpretation. Computer processing of LANDSAT data to improve image quality is essential; the removal of scanline stripping and enhancement of mine land reflectance data combined with color composite printing permits useful photographic enlargements to approximately 1:60,000.

Electroactive Polymers as Artificial Muscles - Reality and Challenges

NASA Technical Reports Server (NTRS)

Bar-Cohen, Y.

2001-01-01

Electroactive Polymers (EAPs) are emerging as effective displacement actuators. These materials offer the closest resemblance of biological muscle potentially enabling unique capabilities changing the paradigm about robots construction. Under a NASA task, several EAP driven mechanisms were developed including dust wiper, gripper, and robotic arm EAP are inducing a low actuation force limiting the applications that can use their current capability. In recognition of this limitation a series of international forums were established including SPIE conference, Webhub, Newsletter, and Newsgroup. A challenge was posed to the EAP community to have an arm wrestling between robot that is equipped with EAP actuators and human.

Thermal Skin fabrication technology

NASA Technical Reports Server (NTRS)

Milam, T. B.

1972-01-01

Advanced fabrication techniques applicable to Thermal Skin structures were investigated, including: (1) chemical machining; (2) braze bonding; (3) diffusion bonding; and (4) electron beam welding. Materials investigated were nickel and nickel alloys. Sample Thermal Skin panels were manufactured using the advanced fabrication techniques studied and were structurally tested. Results of the program included: (1) development of improved chemical machining processes for nickel and several nickel alloys; (2) identification of design geometry limits; (3) identification of diffusion bonding requirements; (4) development of a unique diffusion bonding tool; (5) identification of electron beam welding limits; and (6) identification of structural properties of Thermal Skin material.

Repetitively pulsed TEA CO{sub 2} laser and its application for second harmonic generation in ZnGeP{sub 2} crystal

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

Koval'chuk, L V; Grezev, A N; Niz'ev, V G

2015-10-31

Experimental results are presented on the development of a radiation source emitting at a wavelength of 4.775 μm with a pulse energy up to 50 mJ and an average power up to several watts in short pulse trains. A TEA CO{sub 2} laser and a nonlinear converter based on a ZnGeP{sub 2} crystal, which are specially designed for these experiments, are described. The main limitations of nonlinear conversion and possible ways to overcome these limitations are considered. (lasers)

Expedited CT-Based Methods for Evaluating Fracture Severity to Assess Risk of Post-Traumatic Osteoarthritis After Articular Fractures.

PubMed

Anderson, Donald D; Kilburg, Anthony T; Thomas, Thaddeus P; Marsh, J Lawrence

2016-01-01

Post-traumatic osteoarthritis (PTOA) is common after intra-articular fractures of the tibial plafond. An objective CT-based measure of fracture severity was previously found to reliably predict whether PTOA developed following surgical treatment of such fractures. However, the extended time required obtaining the fracture energy metric and its reliance upon an intact contralateral limb CT limited its clinical applicability. The objective of this study was to establish an expedited fracture severity metric that provided comparable PTOA predictive ability without the prior limitations. An expedited fracture severity metric was computed from the CT scans of 30 tibial plafond fractures using textural analysis to quantify disorder in CT images. The expedited method utilized an intact surrogate model to enable severity assessment without requiring a contralateral limb CT. Agreement between the expedited fracture severity metric and the Kellgren-Lawrence (KL) radiographic OA score at two-year follow-up was assessed using concordance. The ability of the metric to differentiate between patients that did or did not develop PTOA was assessed using the Wilcoxon Ranked Sum test. The expedited severity metric agreed well (75.2% concordance) with the KL scores. The initial fracture severity of cases that developed PTOA differed significantly (p = 0.004) from those that did not. Receiver operating characteristic analysis showed that the expedited severity metric could accurately predict PTOA outcome in 80% of the cases. The time required to obtain the expedited severity metric averaged 14.9 minutes/ case, and the metric was obtained without using an intact contralateral CT. The expedited CT-based methods for fracture severity assessment present a solution to issues limiting the utility of prior methods. In a relatively short amount of time, the expedited methodology provided a severity score capable of predicting PTOA risk, without needing to have the intact contralateral limb included in the CT scan. The described methods provide surgeons an objective, quantitative representation of the severity of a fracture. Obtained prior to the surgery, it provides a reasonable alternative to current subjective classification systems. The expedited severity metric offers surgeons an objective means for factoring severity of joint insult into treatment decision-making.

Applications of biomechanics for prevention of work-related musculoskeletal disorders.

PubMed

Garg, Arun; Kapellusch, Jay M

2009-01-01

This paper summarises applications of biomechanical principles and models in industry to control musculoskeletal disorders of the low back and upper extremity. Applications of 2-D and 3-D biomechanical models to estimate compressive force on the low back, the strength requirements of jobs, application of guidelines for overhead work and application of strain index and threshold limit value to address distal upper extremity musculoskeletal disorders are presented. Several case studies applied in the railroad industry, manufacturing, healthcare and warehousing are presented. Finally, future developments needed for improved biomechanical applications in industry are discussed. The information presented will be of value to practising ergonomists to recognise how biomechanics has played a significant role in identifying causes of musculoskeletal disorders and controlling them in the workplace. In particular, the information presented will help practising ergonomists with how physical stresses can be objectively quantified.

The Role of Participatory Design in Mobile Application Development

NASA Astrophysics Data System (ADS)

Hamzah, Almed

2018-03-01

Mobile devices are used by people worldwide. It becomes a common equipment to complete a day-to-day activity. Inside the devices, there are numerous mobile applications that have been built for various needs. Some of these are quite successful while the other are not. The development of successful mobile application faces several challenges. In this research, we want to explore the use of participatory design method in mobile application development. Particularly, the aim of the study is to answer the question whether participatory design method has a place in the realm of mobile application development. We established two sessions of workshop to accommodate the participant to take part in the development process of mobile application. The result shows that participatory design method can determine how the user will deal with the limitations of mobile devices. It helps user to create a particular form of interaction that meets mobile devices characteristics.

Current Status and Research into Overcoming Limitations of Capsule Endoscopy

PubMed Central

Kwack, Won Gun; Lim, Yun Jeong

2016-01-01

Endoscopic investigation has a critical role in the diagnosis and treatment of gastrointestinal (GI) diseases. Since 2001, capsule endoscopy (CE) has been available for small-bowel exploration and is under continuous development. During the past decade, CE has achieved impressive improvements in areas such as miniaturization, resolution, and battery life. As a result, CE is currently a first-line tool for the investigation of the small bowel in obscure gastrointestinal bleeding and is a useful alternative to wired enteroscopy. Nevertheless, CE still has several limitations, such as incomplete examination and limited diagnostic and therapeutic capabilities. To resolve these problems, many groups have suggested several models (e.g., controlled CO2 insufflation system, magnetic navigation system, mobile robotic platform, tagging and biopsy equipment, and targeted drug-delivery system), which are in development. In the near future, new technological advances will improve the capabilities of CE and broaden its spectrum of applications not only for the small bowel but also for the colon, stomach, and esophagus. The purpose of this review is to introduce the current status of CE and to review the ongoing development of solutions to address its limitations. PMID:26855917

Use of application containers and workflows for genomic data analysis.

PubMed

Schulz, Wade L; Durant, Thomas J S; Siddon, Alexa J; Torres, Richard

2016-01-01

The rapid acquisition of biological data and development of computationally intensive analyses has led to a need for novel approaches to software deployment. In particular, the complexity of common analytic tools for genomics makes them difficult to deploy and decreases the reproducibility of computational experiments. Recent technologies that allow for application virtualization, such as Docker, allow developers and bioinformaticians to isolate these applications and deploy secure, scalable platforms that have the potential to dramatically increase the efficiency of big data processing. While limitations exist, this study demonstrates a successful implementation of a pipeline with several discrete software applications for the analysis of next-generation sequencing (NGS) data. With this approach, we significantly reduced the amount of time needed to perform clonal analysis from NGS data in acute myeloid leukemia.

Applications of plasma core reactors to terrestrial energy systems

NASA Technical Reports Server (NTRS)

Latham, T. S.; Biancardi, F. R.; Rodgers, R. J.

1974-01-01

Plasma core reactors offer several new options for future energy needs in addition to space power and propulsion applications. Power extraction from plasma core reactors with gaseous nuclear fuel allows operation at temperatures higher than conventional reactors. Highly efficient thermodynamic cycles and applications employing direct coupling of radiant energy are possible. Conceptual configurations of plasma core reactors for terrestrial applications are described. Closed-cycle gas turbines, MHD systems, photo- and thermo-chemical hydrogen production processes, and laser systems using plasma core reactors as prime energy sources are considered. Cycle efficiencies in the range of 50 to 65 percent are calculated for closed-cycle gas turbine and MHD electrical generators. Reactor advantages include continuous fuel reprocessing which limits inventory of radioactive by-products and thorium-U-233 breeder configurations with about 5-year doubling times.-

Final Report: Sensorpedia Phases 1 and 2

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

Gorman, Bryan L; Resseguie, David R

2010-08-01

Over the past several years, ORNL has been actively involved in research to formalize the engineering principles and best practices behind emerging social media and social networking concepts to solve real-time data sharing problems for national security and defense, public health and safety, environmental and infrastructure awareness, and disaster preparedness and response. Sensorpedia, an ORNL web site, is a practical application of several key social media principles. Dubbed the Wikipedia for sensors, Sensorpedia is currently in limited BETA testing and was selected in 2009 by Federal Computer Week as one of the government s top 10 social networking sites.

Results from the first single cell Nb 3Sn cavity coatings at JLab

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

Eremeev, Grigory

2015-09-01

Nb 3Sn is a promising superconducting material for SRF applications and has the potential to exceed the limitations of niobium. We have used the recently commissioned Nb 3Sn coating system to investigate Nb 3Sn coatings on several single cell cavities by applying the same coating procedure on several different single cells with different history and pre-coating surface preparation. We report on our findings with four 1.5 GHz CEBAF-shape single cell and one 1.3 GHz ILC-shape single cavities that were coated, inspected, and tested.

Computational Fluid Dynamics Technology for Hypersonic Applications

NASA Technical Reports Server (NTRS)

Gnoffo, Peter A.

2003-01-01

Several current challenges in computational fluid dynamics and aerothermodynamics for hypersonic vehicle applications are discussed. Example simulations are presented from code validation and code benchmarking efforts to illustrate capabilities and limitations. Opportunities to advance the state-of-art in algorithms, grid generation and adaptation, and code validation are identified. Highlights of diverse efforts to address these challenges are then discussed. One such effort to re-engineer and synthesize the existing analysis capability in LAURA, VULCAN, and FUN3D will provide context for these discussions. The critical (and evolving) role of agile software engineering practice in the capability enhancement process is also noted.

Clinical Applications of Gastrointestinal Manometry in Children

PubMed Central

2014-01-01

Manometry is a noninvasive diagnostic tool for identifying motility dysfunction of the gastrointestinal tract. Despite the great technical advances in monitoring motility, performance of the study in pediatric patients has several limitations that should be considered during the procedure and interpretation of the test results. This article reviews the clinical applications of conventional esophageal and anorectal manometries in children by describing a technique for performing the test. This review will develop the uniformity required for the methods of performance, the parameters for measurement, and interpretation of test results that could be applied in pediatric clinical practice. PMID:24749084

Portable tongue-supported human computer interaction system design and implementation.

PubMed

Quain, Rohan; Khan, Masood Mehmood

2014-01-01

Tongue supported human-computer interaction (TSHCI) systems can help critically ill patients interact with both computers and people. These systems can be particularly useful for patients suffering injuries above C7 on their spinal vertebrae. Despite recent successes in their application, several limitations restrict performance of existing TSHCI systems and discourage their use in real life situations. This paper proposes a low-cost, less-intrusive, portable and easy to use design for implementing a TSHCI system. Two applications of the proposed system are reported. Design considerations and performance of the proposed system are also presented.

Polymeric metallic electrodes for rechargeable battery applications

NASA Technical Reports Server (NTRS)

Somoano, R.

1982-01-01

A review is presented on the status of plastic metal electrodes, emphasizing the use of polyacetylene as a prototype polymeric material. The electrochemical characteristics of polyacetylene are examined; and the potential use of this material, as well as other types of plastic metal electrodes, in batteries is evaluated. Several problem areas which must be solved before polyacetylene can be widely used in battery applications are discussed, including the problem of electrolyte stability, the problem that the depth of discharge and the energy density is limited by the metal-semiconductor transition, and also the poor electrochemical performance of impure material.

Micro- and Nano-Scale Electrically Driven Two-Phase Thermal Management

NASA Technical Reports Server (NTRS)

Didion, Jeffrey R.

2016-01-01

This presentation discusses ground based proof of concept hardware under development at NASA GSFC to address high heat flux thermal management in silicon substrates. The goal is to develop proof of concept hardware for space flight validation. The space flight hardware will provide gravity insensitive thermal management for electronics applications such as transmit receive modules that are severely limited by thermal concerns.

EPA eXcats

EPA Pesticide Factsheets

The EPA eXcats is an enterprise-level data tracking application that provides management complaint tracking information for the EPA's Office of Civil Rights (OCR) External Compliance Program. EPA's OCR is responsible for enforcing several federal civil rights laws that together prohibit discrimination on the bases of race, color, national origin (including limited English proficiency), disability, sex and age in programs or activities that receive federal financial assistance from the EPA.

Urban bioclimatology in developing countries.

PubMed

Jauregui, E

1993-11-15

A brief review of the literature on urban human bioclimatology in the tropics is undertaken. Attempts to chart human bioclimatic conditions on the regional/local scale have been made in several developing countries. The effective temperature scheme (with all its limitations) is the one that has been most frequently applied. The possibilities of application of bioclimatic models based on human heat balance for the tropical urban environment are discussed.

Certain topological properties and duals of the domain of a triangle matrix in a sequence space

NASA Astrophysics Data System (ADS)

Altay, Bilâl; Basar, Feyzi

2007-12-01

The matrix domain of the particular limitation methods Cesàro, Riesz, difference, summation and Euler were studied by several authors. In the present paper, certain topological properties and [beta]- and [gamma]-duals of the domain of a triangle matrix in a sequence space have been examined as an application of the characterization of the related matrix classes.

Development of Advanced Spacecraft Thermal Subsystems

NASA Technical Reports Server (NTRS)

Didion, Jeffrey R.

2016-01-01

This presentation discusses ground based proof of concept hardware under development at NASA GSFC to address high heat flux thermal management in silicon substrates and embedded thermal management systems. The goal is to develop proof of concept hardware for space flight validation. The space flight hardware will provide gravity insensitive thermal management for electronics applications such as transmit/receive modules that are severely limited by thermal concerns.

Design for inadvertent damage in composite laminates

NASA Technical Reports Server (NTRS)

Singhal, Surendra N.; Chamis, Christos C.

1992-01-01

Simplified predictive methods and models to computationally simulate durability and damage in polymer matrix composite materials/structures are described. The models include (1) progressive fracture, (2) progressively damaged structural behavior, (3) progressive fracture in aggressive environments, (4) stress concentrations, and (5) impact resistance. Several examples are included to illustrate applications of the models and to identify significant parameters and sensitivities. Comparisons with limited experimental data are made.

New trends in the nucleation research

NASA Astrophysics Data System (ADS)

Anisimov, M. P.; Hopke, P. K.

2017-09-01

During the last half of century the most of efforts have been directed towards small molecule system modeling using intermolecular potentials. Summarizing the nucleation theory, it can be concluded that the nowadays theory is far from complete. The vapor-gas nucleation theory can produce values that deviate from the experimental results by several orders of magnitude currently. Experiments on the vapor-gas nucleation rate measurements using different devices show significant inconsistencies in the measured rates as well. Theoretical results generally are quite reasonable for sufficiently low vapor nucleation rates where the capillary approximation is applicable. In the present research the advantages and current problems of the vapor-gas nucleation experiments are discussed briefly and a view of the future studies is presented. Using the brake points of the first derivative for the nucleation rate surface as markers of the critical embryos phase change is fresh idea to show the gas-pressure effect for the nucleating vapor-gas systems. To test the accuracy of experimental techniques, it is important to have a standard system that can be measured over a range of nucleation conditions. Several results illustrate that high-pressure techniques are needed to study multi-channel nucleation. In practical applications, parametric theories can be used for the systems of interest. However, experimental measurements are still the best source of information on nucleation rates. Experiments are labor intensive and costly, and thus, it is useful to extend the value of limited experimental measurements to a broader range of nucleation conditions. Only limited experimental data one needs for use in normalizing the slopes of the linearized nucleation rate surfaces. The nucleation rate surface is described in terms of steady-state nucleation rates. It is supposed that several new measuring systems, such as High Pressure Flow Diffusion Chamber for pressure limit up to 150 bar will be created soon in the frame of the Russian Ministry of Science & Education project under Contract № 14.Z50.31.0041 issued by February 13th of 2017. The Project will provide the nucleation studies for basic problems of theoretical and practical applications. Published under licence in Journal Title by IOP Publishing Ltd.

Uncertainty Analysis in Space Radiation Protection

NASA Technical Reports Server (NTRS)

Cucinotta, Francis A.

2011-01-01

Space radiation is comprised of high energy and charge (HZE) nuclei, protons, and secondary radiation including neutrons. The uncertainties in estimating the health risks from galactic cosmic rays (GCR) are a major limitation to the length of space missions, the evaluation of potential risk mitigation approaches, and application of the As Low As Reasonably Achievable (ALARA) principle. For long duration space missio ns, risks may approach radiation exposure limits, therefore the uncertainties in risk projections become a major safety concern and methodologies used for ground-based works are not deemed to be sufficient. NASA limits astronaut exposures to a 3% risk of exposure induced death (REID) and protects against uncertainties in risks projections using an assessment of 95% confidence intervals in the projection model. We discuss NASA s approach to space radiation uncertainty assessments and applications for the International Space Station (ISS) program and design studies of future missions to Mars and other destinations. Several features of NASA s approach will be discussed. Radiation quality descriptions are based on the properties of radiation tracks rather than LET with probability distribution functions (PDF) for uncertainties derived from radiobiology experiments at particle accelerators. The application of age and gender specific models for individual astronauts is described. Because more than 90% of astronauts are never-smokers, an alternative risk calculation for never-smokers is used and will be compared to estimates for an average U.S. population. Because of the high energies of the GCR limits the benefits of shielding and the limited role expected for pharmaceutical countermeasures, uncertainty reduction continues to be the optimal approach to improve radiation safety for space missions.

Contributed Review: Camera-limits for wide-field magnetic resonance imaging with a nitrogen-vacancy spin sensor

NASA Astrophysics Data System (ADS)

Wojciechowski, Adam M.; Karadas, Mürsel; Huck, Alexander; Osterkamp, Christian; Jankuhn, Steffen; Meijer, Jan; Jelezko, Fedor; Andersen, Ulrik L.

2018-03-01

Sensitive, real-time optical magnetometry with nitrogen-vacancy centers in diamond relies on accurate imaging of small (≪10-2), fractional fluorescence changes across the diamond sample. We discuss the limitations on magnetic field sensitivity resulting from the limited number of photoelectrons that a camera can record in a given time. Several types of camera sensors are analyzed, and the smallest measurable magnetic field change is estimated for each type. We show that most common sensors are of a limited use in such applications, while certain highly specific cameras allow achieving nanotesla-level sensitivity in 1 s of a combined exposure. Finally, we demonstrate the results obtained with a lock-in camera that paves the way for real-time, wide-field magnetometry at the nanotesla level and with a micrometer resolution.

Antibody Fragments as Potential Biopharmaceuticals for Cancer Therapy: Success and Limitations.

PubMed

Kholodenko, Roman V; Kalinovsky, Daniel V; Doronin, Igor I; Ponomarev, Eugene D; Kholodenko, Irina V

2017-08-17

Monoclonal antibodies (mAbs) are an important class of therapeutic agents approved for the therapy of many types of malignancies. However, in certain cases applications of conventional mAbs have several limitations in anticancer immunotherapy. These limitations include insufficient efficacy and adverse effects. The antigen-binding fragments of antibodies have a considerable potential to overcome the disadvantages of conventional mAbs, such as poor penetration into solid tumors and Fc-mediated bystander activation of the immune system. Fragments of antibodies retain antigen specificity and part of functional properties of conventional mAbs and at the same time have much better penetration into the tumors and a greatly reduced level of adverse effects. Recent advantages in antibody engineering allowed to produce different types of antibody fragments with improved structure and properties for efficient elimination of tumor cells. These molecules opened up new perspectives for anticancer therapy. Here we will overview the structural features of the various types of antibody fragments and their applications for anticancer therapy as separate molecules and as part of complex conjugates or structures. Mechanisms of antitumor action of antibody fragments as well as their advantages and disadvantages for clinical application will be discussed in this review. Copyright© Bentham Science Publishers; For any queries, please email at epub@benthamscience.org.

Environmental radioactivity measurements and applications - Difficulties, current status and future trends

NASA Astrophysics Data System (ADS)

Anagnostakis, Marios J.

2015-11-01

For several decades natural and artificial radioactivity in the environment have been extensively studied all around the world. Nuclear accidents - mainly that of Chernobyl - have led to the development of the field of radioecology, while detector systems and techniques - with predominant that of γ-spectrometry - have been continuously developed through the years to meet researchers' needs. The study of natural radionuclides that was originally limited to 226Ra, 232Th and 40K was then extended to include radionuclides such as 234Th, 210Pb, 235U and 7Be, which allowed the study of radioactive equilibrium. Besides their importance from the radiation protection point of view, many radionuclides are also used as tracers of environmental processes, such as aerosol and transportation of air masses studies (7Be, 10Be, 22Na), soil erosion, sedimentation and geochronology (210Pb, 137Cs), marine ecosystems studies and studies related to climate change. All these studies require specialized samplings strategies and sampling preparation techniques as well as high quality measurements, while the improvement of detection limits is often of vital importance. This work is a review of environmental radioactivity measurements and applications, mainly focused in the field of γ-spectrometry, for which difficulties and limitations will be presented, together with future trends, new challenges and applications.

Gene therapy delivery systems for enhancing viral and nonviral vectors for cardiac diseases: current concepts and future applications.

PubMed

Katz, Michael G; Fargnoli, Anthony S; Williams, Richard D; Bridges, Charles R

2013-11-01

Gene therapy is one of the most promising fields for developing new treatments for the advanced stages of ischemic and monogenetic, particularly autosomal or X-linked recessive, cardiomyopathies. The remarkable ongoing efforts in advancing various targets have largely been inspired by the results that have been achieved in several notable gene therapy trials, such as the hemophilia B and Leber's congenital amaurosis. Rate-limiting problems preventing successful clinical application in the cardiac disease area, however, are primarily attributable to inefficient gene transfer, host responses, and the lack of sustainable therapeutic transgene expression. It is arguable that these problems are directly correlated with the choice of vector, dose level, and associated cardiac delivery approach as a whole treatment system. Essentially, a delicate balance exists in maximizing gene transfer required for efficacy while remaining within safety limits. Therefore, the development of safe, effective, and clinically applicable gene delivery techniques for selected nonviral and viral vectors will certainly be invaluable in obtaining future regulatory approvals. The choice of gene transfer vector, dose level, and the delivery system are likely to be critical determinants of therapeutic efficacy. It is here that the interactions between vector uptake and trafficking, delivery route means, and the host's physical limits must be considered synergistically for a successful treatment course.

Capability of Sputtered Micro-patterned NiTi Thick Films

NASA Astrophysics Data System (ADS)

Bechtold, Christoph; Lima de Miranda, Rodrigo; Quandt, Eckhard

2015-09-01

Today, most NiTi devices are manufactured by a combination of conventional metal fabrication steps, e.g., melting, extrusion, cold working, etc., and are subsequently structured by high accuracy laser cutting. This combination has been proven to be very successful; however, there are several limitations to this fabrication route, e.g., in respect to the fabrication of more complex device designs, device miniaturization or the combination of different materials for the integration of further functionality. These issues have to be addressed in order to develop new devices and applications. The fabrication of micro-patterned films using magnetron sputtering, UV lithography, and wet etching has great potential to overcome limitations of conventional device manufacturing. Due to its fabrication characteristics, this method allows the production of devices with complex designs, high structural accuracy, smooth edge profile, at layer thicknesses up to 75 µm. The aim of this study is to present recent developments in the field of NiTi thin film technology, its advantages and limitations, as well as new possible applications in the medical and in non-medical fields. These developments include among others NiTi scaffold structures covered with NiTi membranes for their potential use as filters, heart valve components or aneurysm treatments, as well as micro-actuators for consumable electronics or automotive applications.

Hardware for hard-up schools?

NASA Astrophysics Data System (ADS)

St John, Stuart A.

2012-01-01

The purpose of this work was to investigate ways in which everyday computers can be used in schools to fulfil several of the roles of more expensive, specialized laboratory equipment for teaching and learning purposes. The brief adopted was to keep things as straightforward as possible so that any school science department with a few basic tools can copy the ideas presented. The project has so far produced a simple, safe input device to enable use of a computer as an oscilloscope and the conversion of external speakers into a signal generator. They are not without their limitations, but the intention is that they may provide opportunities for hands-on learning in schools where budgets are very limited. Several teaching ideas are outlined, with pointers for further development. It is hoped that interest in the project may generate further application of the ideas to the teaching of high school physics.

Intracellular cellobiose metabolism and its applications in lignocellulose-based biorefineries.

PubMed

Parisutham, Vinuselvi; Chandran, Sathesh-Prabu; Mukhopadhyay, Aindrila; Lee, Sung Kuk; Keasling, Jay D

2017-09-01

Complete hydrolysis of cellulose has been a key characteristic of biomass technology because of the limitation of industrial production hosts to use cellodextrin, the partial hydrolysis product of cellulose. Cellobiose, a β-1,4-linked glucose dimer, is a major cellodextrin of the enzymatic hydrolysis (via endoglucanase and exoglucanase) of cellulose. Conversion of cellobiose to glucose is executed by β-glucosidase. The complete extracellular hydrolysis of celluloses has several critical barriers in biomass technology. An alternative bioengineering strategy to make the bioprocessing less challenging is to engineer microbes with the abilities to hydrolyze and assimilate the cellulosic-hydrolysate cellodextrin. Microorganisms engineered to metabolize cellobiose rather than the monomeric glucose can provide several advantages for lignocellulose-based biorefineries. This review describes the recent advances and challenges in engineering efficient intracellular cellobiose metabolism in industrial hosts. This review also describes the limitations of and future prospectives in engineering intracellular cellobiose metabolism. Copyright © 2017 Elsevier Ltd. All rights reserved.

Numerical modeling of consolidation processes in hydraulically deposited soils

NASA Astrophysics Data System (ADS)

Brink, Nicholas Robert

Hydraulically deposited soils are encountered in many common engineering applications including mine tailing and geotextile tube fills, though the consolidation process for such soils is highly nonlinear and requires the use of advanced numerical techniques to provide accurate predictions. Several commercially available finite element codes poses the ability to model soil consolidation, and it was the goal of this research to assess the ability of two of these codes, ABAQUS and PLAXIS, to model the large-strain, two-dimensional consolidation processes which occur in hydraulically deposited soils. A series of one- and two-dimensionally drained rectangular models were first created to assess the limitations of ABAQUS and PLAXIS when modeling consolidation of highly compressible soils. Then, geotextile tube and TSF models were created to represent actual scenarios which might be encountered in engineering practice. Several limitations were discovered, including the existence of a minimum preconsolidation stress below which numerical solutions become unstable.

Intracellular cellobiose metabolism and its applications in lignocellulose-based biorefineries

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

Parisutham, Vinuselvi; Chandran, Sathesh-Prabu; Mukhopadhyay, Aindrila

Complete hydrolysis of cellulose has been noted as a key characteristic of biomass technology due to the limitation of industrial production hosts to use cellodextrin, the partial hydrolysis product of cellulose. Cellobiose, a β-1,4-linked glucose dimer, is a major cellodextrin of the enzymatic hydrolysis (via endoglucanase and exoglucanase) of cellulose. Conversion of cellobiose to glucose is executed by β-glucosidase. The complete extracellular hydrolysis of celluloses has several critical barriers in biomass technology. An alternative bioengineering strategy to make the bioprocessing less challenging is to engineer microbes with the abilities to hydrolyze and assimilate the cellulosic-hydrolysate cellodextrin. Microorganisms engineered to metabolizemore » cellobiose rather than the monomeric glucose can provide several advantages for lignocellulose-based biorefineries. This review describes the recent advances and challenges in engineering efficient intracellular cellobiose metabolism in industrial hosts. This review also describes the limitations of and future prospectives in engineering intracellular cellobiose metabolism.« less

Health systems engineering fellowship: curriculum and program development.

PubMed

Watts, Bradley V; Shiner, Brian; Cully, Jeffrey A; Gilman, Stuart C; Benneyan, James C; Eisenhauer, William

2015-01-01

Industrial engineering and related disciplines have been used widely in improvement efforts in many industries. These approaches have been less commonly attempted in health care. One factor limiting application is the limited workforce resulting from a lack of specific education and professional development in health systems engineering (HSE). The authors describe the development of an HSE fellowship within the United States Department of Veterans Affairs, Veterans Health Administration (VA). This fellowship includes a novel curriculum based on specifically established competencies for HSE. A 1-year HSE curriculum was developed and delivered to fellows at several VA engineering resource centers over several years. On graduation, a majority of the fellows accepted positions in the health care field. Challenges faced in developing the fellowship are discussed. Advanced educational opportunities in applied HSE have the potential to develop the workforce capacity needed to improve the quality of health care. © 2014 by the American College of Medical Quality.

High Tensile Strength Amalgams for In-Space Fabrication and Repair

NASA Technical Reports Server (NTRS)

Grugel, Richard N.

2006-01-01

Amalgams are well known for their use in dental practice as a tooth filling material. They have a number of useful attributes that include room temperature fabrication, corrosion resistance, dimensional stability, and very good compressive strength. These properties well serve dental needs but, unfortunately, amalgams have extremely poor tensile strength, a feature that severely limits other potential applications. Improved material properties (strength and temperature) of amalgams may have application to the freeform fabrication of repairs or parts that might be necessary during an extended space mission. Advantages would include, but are not limited to: the ability to produce complex parts, a minimum number of processing steps, minimum crew interaction, high yield - minimum wasted material, reduced gravity compatibility, minimum final finishing, safety, and minimum power consumption. The work presented here shows how the properties of amalgams can be improved by changing particle geometries in conjunction with novel engineering metals.

Status and prospects of computational fluid dynamics for unsteady transonic viscous flows

NASA Technical Reports Server (NTRS)

Mccroskey, W. J.; Kutler, P.; Bridgeman, J. O.

1984-01-01

Applications of computational aerodynamics to aeronautical research, design, and analysis have increased rapidly over the past decade, and these applications offer significant benefits to aeroelasticians. The past developments are traced by means of a number of specific examples, and the trends are projected over the next several years. The crucial factors that limit the present capabilities for unsteady analyses are identified; they include computer speed and memory, algorithm and solution methods, grid generation, turbulence modeling, vortex modeling, data processing, and coupling of the aerodynamic and structural dynamic analyses. The prospects for overcoming these limitations are presented, and many improvements appear to be readily attainable. If so, a complete and reliable numerical simulation of the unsteady, transonic viscous flow around a realistic fighter aircraft configuration could become possible within the next decade. The possibilities of using artificial intelligence concepts to hasten the achievement of this goal are also discussed.

Polymer-based actuators for virtual reality devices

NASA Astrophysics Data System (ADS)

Bolzmacher, Christian; Hafez, Moustapha; Benali Khoudja, Mohamed; Bernardoni, Paul; Dubowsky, Steven

2004-07-01

Virtual Reality (VR) is gaining more importance in our society. For many years, VR has been limited to the entertainment applications. Today, practical applications such as training and prototyping find a promising future in VR. Therefore there is an increasing demand for low-cost, lightweight haptic devices in virtual reality (VR) environment. Electroactive polymers seem to be a potential actuation technology that could satisfy these requirements. Dielectric polymers developed the past few years have shown large displacements (more than 300%). This feature makes them quite interesting for integration in haptic devices due to their muscle-like behaviour. Polymer actuators are flexible and lightweight as compared to traditional actuators. Using stacks with several layers of elatomeric film increase the force without limiting the output displacement. The paper discusses some design methods for a linear dielectric polymer actuator for VR devices. Experimental results of the actuator performance is presented.

A methodology for computing uncertainty bounds of multivariable systems based on sector stability theory concepts

NASA Technical Reports Server (NTRS)

Waszak, Martin R.

1992-01-01

The application of a sector-based stability theory approach to the formulation of useful uncertainty descriptions for linear, time-invariant, multivariable systems is explored. A review of basic sector properties and sector-based approach are presented first. The sector-based approach is then applied to several general forms of parameter uncertainty to investigate its advantages and limitations. The results indicate that the sector uncertainty bound can be used effectively to evaluate the impact of parameter uncertainties on the frequency response of the design model. Inherent conservatism is a potential limitation of the sector-based approach, especially for highly dependent uncertain parameters. In addition, the representation of the system dynamics can affect the amount of conservatism reflected in the sector bound. Careful application of the model can help to reduce this conservatism, however, and the solution approach has some degrees of freedom that may be further exploited to reduce the conservatism.

Field-Induced and Thermal Electron Currents from Earthed Spherical Emitters

NASA Astrophysics Data System (ADS)

Holgate, J. T.; Coppins, M.

2017-04-01

The theories of electron emission from planar surfaces are well understood, but they are not suitable for describing emission from spherical surfaces; their incorrect application to highly curved, nanometer-scale surfaces can overestimate the emitted current by several orders of magnitude. This inaccuracy is of particular concern for describing modern nanoscale electron sources, which continue to be modeled using the planar equations. In this paper, the field-induced and thermal currents are treated in a unified way to produce Fowler-Nordheim-type and Richardson-Schottky-type equations for the emitted current density from earthed nanoscale spherical surfaces. The limits of applicability of these derived expressions are considered along with the energy spectra of the emitted electrons. Within the relevant limits of validity, these equations are shown to reproduce the results of precise numerical calculations of the emitted current densities. The methods used here are adaptable to other one-dimensional emission problems.

Reviewing the connection between speech and obstructive sleep apnea.

PubMed

Espinoza-Cuadros, Fernando; Fernández-Pozo, Rubén; Toledano, Doroteo T; Alcázar-Ramírez, José D; López-Gonzalo, Eduardo; Hernández-Gómez, Luis A

2016-02-20

Sleep apnea (OSA) is a common sleep disorder characterized by recurring breathing pauses during sleep caused by a blockage of the upper airway (UA). The altered UA structure or function in OSA speakers has led to hypothesize the automatic analysis of speech for OSA assessment. In this paper we critically review several approaches using speech analysis and machine learning techniques for OSA detection, and discuss the limitations that can arise when using machine learning techniques for diagnostic applications. A large speech database including 426 male Spanish speakers suspected to suffer OSA and derived to a sleep disorders unit was used to study the clinical validity of several proposals using machine learning techniques to predict the apnea-hypopnea index (AHI) or classify individuals according to their OSA severity. AHI describes the severity of patients' condition. We first evaluate AHI prediction using state-of-the-art speaker recognition technologies: speech spectral information is modelled using supervectors or i-vectors techniques, and AHI is predicted through support vector regression (SVR). Using the same database we then critically review several OSA classification approaches previously proposed. The influence and possible interference of other clinical variables or characteristics available for our OSA population: age, height, weight, body mass index, and cervical perimeter, are also studied. The poor results obtained when estimating AHI using supervectors or i-vectors followed by SVR contrast with the positive results reported by previous research. This fact prompted us to a careful review of these approaches, also testing some reported results over our database. Several methodological limitations and deficiencies were detected that may have led to overoptimistic results. The methodological deficiencies observed after critically reviewing previous research can be relevant examples of potential pitfalls when using machine learning techniques for diagnostic applications. We have found two common limitations that can explain the likelihood of false discovery in previous research: (1) the use of prediction models derived from sources, such as speech, which are also correlated with other patient characteristics (age, height, sex,…) that act as confounding factors; and (2) overfitting of feature selection and validation methods when working with a high number of variables compared to the number of cases. We hope this study could not only be a useful example of relevant issues when using machine learning for medical diagnosis, but it will also help in guiding further research on the connection between speech and OSA.

Lightweight Adaptation of Classifiers to Users and Contexts: Trends of the Emerging Domain

PubMed Central

Vildjiounaite, Elena; Gimel'farb, Georgy; Kyllönen, Vesa; Peltola, Johannes

2015-01-01

Intelligent computer applications need to adapt their behaviour to contexts and users, but conventional classifier adaptation methods require long data collection and/or training times. Therefore classifier adaptation is often performed as follows: at design time application developers define typical usage contexts and provide reasoning models for each of these contexts, and then at runtime an appropriate model is selected from available ones. Typically, definition of usage contexts and reasoning models heavily relies on domain knowledge. However, in practice many applications are used in so diverse situations that no developer can predict them all and collect for each situation adequate training and test databases. Such applications have to adapt to a new user or unknown context at runtime just from interaction with the user, preferably in fairly lightweight ways, that is, requiring limited user effort to collect training data and limited time of performing the adaptation. This paper analyses adaptation trends in several emerging domains and outlines promising ideas, proposed for making multimodal classifiers user-specific and context-specific without significant user efforts, detailed domain knowledge, and/or complete retraining of the classifiers. Based on this analysis, this paper identifies important application characteristics and presents guidelines to consider these characteristics in adaptation design. PMID:26473165

Identification of widespread adenosine nucleotide binding in Mycobacterium tuberculosis

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

Ansong, Charles; Ortega, Corrie; Payne, Samuel H.

The annotation of protein function is almost completely performed by in silico approaches. However, computational prediction of protein function is frequently incomplete and error prone. In Mycobacterium tuberculosis (Mtb), ~25% of all genes have no predicted function and are annotated as hypothetical proteins. This lack of functional information severely limits our understanding of Mtb pathogenicity. Current tools for experimental functional annotation are limited and often do not scale to entire protein families. Here, we report a generally applicable chemical biology platform to functionally annotate bacterial proteins by combining activity-based protein profiling (ABPP) and quantitative LC-MS-based proteomics. As an example ofmore » this approach for high-throughput protein functional validation and discovery, we experimentally annotate the families of ATP-binding proteins in Mtb. Our data experimentally validate prior in silico predictions of >250 ATPases and adenosine nucleotide-binding proteins, and reveal 73 hypothetical proteins as novel ATP-binding proteins. We identify adenosine cofactor interactions with many hypothetical proteins containing a diversity of unrelated sequences, providing a new and expanded view of adenosine nucleotide binding in Mtb. Furthermore, many of these hypothetical proteins are both unique to Mycobacteria and essential for infection, suggesting specialized functions in mycobacterial physiology and pathogenicity. Thus, we provide a generally applicable approach for high throughput protein function discovery and validation, and highlight several ways in which application of activity-based proteomics data can improve the quality of functional annotations to facilitate novel biological insights.« less

Usage of Human Mesenchymal Stem Cells in Cell-based Therapy: Advantages and Disadvantages.

PubMed

Kim, Hee Jung; Park, Jeong-Soo

2017-03-01

The use of human mesenchymal stem cells (hMSCs) in cell-based therapy has attracted extensive interest in the field of regenerative medicine, and it shows applications to numerous incurable diseases. hMSCs show several superior properties for therapeutic use compared to other types of stem cells. Different cell types are discussed in terms of their advantages and disadvantages, with focus on the characteristics of hMSCs. hMSCs can proliferate readily and produce differentiated cells that can substitute for the targeted affected tissue. To maximize the therapeutic effects of hMSCs, a substantial number of these cells are essential, requiring extensive ex vivo cell expansion. However, hMSCs have a limited lifespan in an in vitro culture condition. The senescence of hMSCs is a double-edged sword from the viewpoint of clinical applications. Although their limited cell proliferation potency protects them from malignant transformation after transplantation, senescence can alter various cell functions including proliferation, differentiation, and migration, that are essential for their therapeutic efficacy. Numerous trials to overcome the limited lifespan of mesenchymal stem cells are discussed.

Usage of Human Mesenchymal Stem Cells in Cell-based Therapy: Advantages and Disadvantages

PubMed Central

Kim, Hee Jung; Park, Jeong-Soo

2017-01-01

ABSTRACT The use of human mesenchymal stem cells (hMSCs) in cell-based therapy has attracted extensive interest in the field of regenerative medicine, and it shows applications to numerous incurable diseases. hMSCs show several superior properties for therapeutic use compared to other types of stem cells. Different cell types are discussed in terms of their advantages and disadvantages, with focus on the characteristics of hMSCs. hMSCs can proliferate readily and produce differentiated cells that can substitute for the targeted affected tissue. To maximize the therapeutic effects of hMSCs, a substantial number of these cells are essential, requiring extensive ex vivo cell expansion. However, hMSCs have a limited lifespan in an in vitro culture condition. The senescence of hMSCs is a double-edged sword from the viewpoint of clinical applications. Although their limited cell proliferation potency protects them from malignant transformation after transplantation, senescence can alter various cell functions including proliferation, differentiation, and migration, that are essential for their therapeutic efficacy. Numerous trials to overcome the limited lifespan of mesenchymal stem cells are discussed. PMID:28484739

Laser assisted robotic surgery in cornea transplantation

NASA Astrophysics Data System (ADS)

Rossi, Francesca; Micheletti, Filippo; Magni, Giada; Pini, Roberto; Menabuoni, Luca; Leoni, Fabio; Magnani, Bernardo

2017-03-01

Robotic surgery is a reality in several surgical fields, such as in gastrointestinal surgery. In ophthalmic surgery the required high spatial precision is limiting the application of robotic system, and even if several attempts have been designed in the last 10 years, only some application in retinal surgery were tested in animal models. The combination of photonics and robotics can really open new frontiers in minimally invasive surgery, improving the precision, reducing tremor, amplifying scale of motion, and automating the procedure. In this manuscript we present the preliminary results in developing a vision guided robotic platform for laser-assisted anterior eye surgery. The robotic console is composed by a robotic arm equipped with an "end effector" designed to deliver laser light to the anterior corneal surface. The main intended application is for laser welding of corneal tissue in laser assisted penetrating keratoplasty and endothelial keratoplasty. The console is equipped with an integrated vision system. The experiment originates from a clear medical demand in order to improve the efficacy of different surgical procedures: when the prototype will be optimized, other surgical areas will be included in its application, such as neurosurgery, urology and spinal surgery.

A robotic platform for laser welding of corneal tissue

NASA Astrophysics Data System (ADS)

Rossi, Francesca; Micheletti, Filippo; Magni, Giada; Pini, Roberto; Menabuoni, Luca; Leoni, Fabio; Magnani, Bernardo

2017-07-01

Robotic surgery is a reality in several surgical fields, such as in gastrointestinal surgery. In ophthalmic surgery the required high spatial precision is limiting the application of robotic system, and even if several attempts have been designed in the last 10 years, only some application in retinal surgery were tested in animal models. The combination of photonics and robotics can really open new frontiers in minimally invasive surgery, improving the precision, reducing tremor, amplifying scale of motion, and automating the procedure. In this manuscript we present the preliminary results in developing a vision guided robotic platform for laser-assisted anterior eye surgery. The robotic console is composed by a robotic arm equipped with an "end effector" designed to deliver laser light to the anterior corneal surface. The main intended application is for laser welding of corneal tissue in laser assisted penetrating keratoplasty and endothelial keratoplasty. The console is equipped with an integrated vision system. The experiment originates from a clear medical demand in order to improve the efficacy of different surgical procedures: when the prototype will be optimized, other surgical areas will be included in its application, such as neurosurgery, urology and spinal surgery.

Potential of novel drug delivery systems in the management of topical candidiasis.

PubMed

Mathur, Mahima; Devi, V Kusum

2017-09-01

High prevalence of topical fungal infections is perceived in majority of nations worldwide accounting for numerous serious systemic complications. Of several fungal infections, candidiasis is one of the widespread infections which is manifested due to localisation and proliferation of fungi. Present pharmacotherapy offers an effective treatment but possesses serious limitations like inadequate solubility, ineffectiveness in lowering diseased condition and patient incompliance. Several attempts to overcome these shortcomings and building suitable technology platforms for development of appropriate dosage forms which can enhance effectiveness, patient acceptability while maintaining safety, efficacy and affordability of drug delivery, have been made. Present review highlights on different types of fungal infections, its aetiology, pathophysiology, epidemiology and conventional formulations used. It also emphasises on applications of several novel approaches of anti-fungal drugs demonstrating advantages and limitations. Details regarding patterns of drug release and its site specificity with better patient compliance have been focussed. Etiology and pathogenesis of candidiasis should be understood clearly. Mentioned novel dosage forms should be explored to enhance therapeutic efficacy, subsequently investigating marketability and patentability. Nanoparticles seem to be a promising approach befitting all requirements.

Microwave amplification based on quasiparticle SIS up and down frequency converters

NASA Astrophysics Data System (ADS)

Kojima, T.; Uzawa, Y.; Shan, W.

2018-02-01

Heterodyne instruments have recently attained quantum-limited low-noise performance, particularly in radio astronomy, but it is difficult to develop large heterodyne arrays such as a modern radio camera using cryogenic sensitive detectors based on microwave kinetic inductance detectors, transition edge sensors, etc. In the realization of the heterodyne array, the reduction of power dissipation for semiconductor-based amplifiers remains a major challenge. Alternatively, superconducting parametric amplifiers still seem to have several barriers to application, especially in terms of operating temperature. Here, we show a novel concept of microwave amplification based on up and down frequency-conversion processes using quasiparticle superconductor-insulator-superconductor (SIS) tunnel junctions. We demonstrate positive gain using a proof-of-concept test module, which operates with a power dissipation of several μW at a bath temperature of 4 K. The performance of the module suggests great potential for application in large arrays.

[Scoring systems in intensive care medicine : principles, models, application and limits].

PubMed

Fleig, V; Brenck, F; Wolff, M; Weigand, M A

2011-10-01

Scoring systems are used in all diagnostic areas of medicine. Several parameters are evaluated and rated with points according to their value in order to simplify a complex clinical situation with a score. The application ranges from the classification of disease severity through determining the number of staff for the intensive care unit (ICU) to the evaluation of new therapies under study conditions. Since the introduction of scoring systems in the 1980's a variety of different score models has been developed. The scoring systems that are employed in intensive care and are discussed in this article can be categorized into prognostic scores, expenses scores and disease-specific scores. Since the introduction of compulsory recording of two scoring systems for accounting in the German diagnosis-related groups (DRG) system, these tools have gained more importance for all intensive care physicians. Problems remain in the valid calculation of scores and interpretation of the results.

A multi-perspective review of microbial fuel-cells for wastewater treatment: Bio-electro-chemical, microbiologic and modeling aspects

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

Capodaglio, Andrea G., E-mail: capo@unipv.it; Molognoni, Daniele; Pons, Anna Vilajeliu

Microbial Fuel Cells (MFCs) represent a still novel technology for the recovery of energy and resources through wastewater treatment. Although the technology is quite appealing, due its potential benefits, its practical application is still hampered by several drawbacks, such as systems instability (especially when attempting to scale-up reactors from laboratory prototype), internally competing microbial reactions, and limited power generation. This paper is an attempt to address several of the operational issues related to MFCs application to wastewater treatment, in particular when dealing with simultaneous organic matter and nitrogen pollution control. Reactor configuration, operational schemes, electrochemical and microbiological characterization, optimization methodsmore » and modelling strategies are reviewed and discussed with a multidisciplinary, multi-perspective approach. The conclusions drawn herein can be of practical interest for all MFC researchers dealing with domestic or industrial wastewater treatment..« less

Examination of Short- and Long-Range Atomic Order Nanocrystalline SiC and Diamond by Powder Diffraction Methods

NASA Technical Reports Server (NTRS)

Palosz, B.; Grzanka, E.; Stelmakh, S.; Gierlotka, S.; Weber, H.-P.; Proffen, T.; Palosz, W.

2002-01-01

The real atomic structure of nanocrystals determines unique, key properties of the materials. Determination of the structure presents a challenge due to inherent limitations of standard powder diffraction techniques when applied to nanocrystals. Alternate methodology of the structural analysis of nanocrystals (several nanometers in size) based on Bragg-like scattering and called the "apparent lattice parameter" (alp) is proposed. Application of the alp methodology to examination of the core-shell model of nanocrystals will be presented. The results of application of the alp method to structural analysis of several nanopowders were complemented by those obtained by determination of the Atomic Pair Distribution Function, PDF. Based on synchrotron and neutron diffraction data measured in a large diffraction vector of up to Q = 25 Angstroms(exp -1), the surface stresses in nanocrystalline diamond and SiC were evaluated.

An electronic nose for quantitative determination of gas concentrations

NASA Astrophysics Data System (ADS)

Jasinski, Grzegorz; Kalinowski, Paweł; Woźniak, Łukasz

2016-11-01

The practical application of human nose for fragrance recognition is severely limited by the fact that our sense of smell is subjective and gets tired easily. Consequently, there is considerable need for an instrument that can be a substitution of the human sense of smell. Electronic nose devices from the mid 1980s are used in growing number of applications. They comprise an array of several electrochemical gas sensors with partial specificity and a pattern recognition algorithms. Most of such systems, however, is only used for qualitative measurements. In this article usage of such system in quantitative determination of gas concentration is demonstrated. Electronic nose consist of a sensor array with eight commercially available Taguchi type gas sensor. Performance of three different pattern recognition algorithms is compared, namely artificial neural network, partial least squares regression and support vector machine regression. The electronic nose is used for ammonia and nitrogen dioxide concentration determination.

Poly(vinylbenzylchloride) Based Anion-Exchange Blend Membranes (AEBMs): Influence of PEG Additive on Conductivity and Stability

PubMed Central

Kerres, Jochen A.; Krieg, Henning M.

2017-01-01

In view of the many possible applications such as fuel cells and electrolysers, recent interest in novel anion exchange membranes (AEMs) has increased significantly. However, their low conductivity and chemical stability limits their current suitability. In this study, the synthesis and characterization of several three- and four-component anion exchange blend membranes (AEBMs) is described, where the compositions have been systematically varied to study the influence of the AEBM’s composition on the anion conductivities as well as chemical and thermal stabilities under strongly alkaline conditions. It was shown that the epoxide-functionalized poly(ethylene glycol)s that were introduced into the four-component AEBMs resulted in increased conductivity as well as a marked improvement in the stability of the AEBMs in an alkaline environment. In addition, the thermal stability of the novel AEBMs was excellent showing the suitability of these membranes for several electrochemical applications. PMID:28621717

Electronic Nose Testing Procedure for the Definition of Minimum Performance Requirements for Environmental Odor Monitoring

PubMed Central

Eusebio, Lidia; Capelli, Laura; Sironi, Selena

2016-01-01

Despite initial enthusiasm towards electronic noses and their possible application in different fields, and quite a lot of promising results, several criticalities emerge from most published research studies, and, as a matter of fact, the diffusion of electronic noses in real-life applications is still very limited. In general, a first step towards large-scale-diffusion of an analysis method, is standardization. The aim of this paper is describing the experimental procedure adopted in order to evaluate electronic nose performances, with the final purpose of establishing minimum performance requirements, which is considered to be a first crucial step towards standardization of the specific case of electronic nose application for environmental odor monitoring at receptors. Based on the experimental results of the performance testing of a commercialized electronic nose type with respect to three criteria (i.e., response invariability to variable atmospheric conditions, instrumental detection limit, and odor classification accuracy), it was possible to hypothesize a logic that could be adopted for the definition of minimum performance requirements, according to the idea that these are technologically achievable. PMID:27657086

Electronic Nose Testing Procedure for the Definition of Minimum Performance Requirements for Environmental Odor Monitoring.

PubMed

Eusebio, Lidia; Capelli, Laura; Sironi, Selena

2016-09-21

Despite initial enthusiasm towards electronic noses and their possible application in different fields, and quite a lot of promising results, several criticalities emerge from most published research studies, and, as a matter of fact, the diffusion of electronic noses in real-life applications is still very limited. In general, a first step towards large-scale-diffusion of an analysis method, is standardization. The aim of this paper is describing the experimental procedure adopted in order to evaluate electronic nose performances, with the final purpose of establishing minimum performance requirements, which is considered to be a first crucial step towards standardization of the specific case of electronic nose application for environmental odor monitoring at receptors. Based on the experimental results of the performance testing of a commercialized electronic nose type with respect to three criteria (i.e., response invariability to variable atmospheric conditions, instrumental detection limit, and odor classification accuracy), it was possible to hypothesize a logic that could be adopted for the definition of minimum performance requirements, according to the idea that these are technologically achievable.

Performance evaluation of the Fiber Bragg Grating (FBG) sensing device and comparison with piezoelectric sensors for AE detection

NASA Astrophysics Data System (ADS)

Zhang, Chuang; Bond, Leonard J.

2017-02-01

Structural health monitoring (SHM) of engineering structures in service has assumed a significant role in assessing their safety and integrity. Several sensing modalities have been developed to monitor cracking, using acoustic emission (AE). Piezoelectric sensors are commonly used in AE systems, however, for some applications there are limitations and challenges. One alternative approach that is being investigated is using Fiber Bragg Grating (FBG) sensors which have emerged as a reliable, in situ and nondestructive tool in some applications for monitoring and diagnostics in large-scale structure. The main objective of this work is to evaluate and compare the AE sensing characteristics for FBG and piezoelectric sensors. A ball drop impact is used as the source for generating waves in an Aluminum plate. The source repeatability was verified and a 4-channel FBG AE detection device was used to compare with the response of PZT sensors, investigating amplitude and frequency response which can indicate sensitivity. The low sensitivity and slow sampling rate are identified, for the unit investigated, as the main factors limiting FBG engineering AE applications.

Modulation bandwidth of spin torque oscillators under current modulation

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

Quinsat, M.; CEA, INAC-SPINTEC, F-38054 Grenoble; CNRS, SPINTEC, F-38054 Grenoble

2014-10-13

For practical applications of spin torque nano-oscillators (STNO), one of the most critical characteristics is the speed at which an STNO responds to variations of external control parameters, such as current or/and field. Theory predicts that this speed is limited by the amplitude relaxation rate Γ{sub p} that determines the timescale over which the amplitude fluctuations are damped out. In this study, this limit is verified experimentally by analyzing the amplitude and frequency noise spectra of the output voltage signal when modulating an STNO by a microwave current. In particular, it is shown that due to the non-isochronous nature ofmore » the STNO the amplitude relaxation rate Γ{sub p} determines not only the bandwidth of an amplitude modulation, but also the bandwidth of a frequency modulation. The presented experimental technique will be important for the optimisation of the STNO characteristics for applications in telecommunications or/and data storage and is applicable even in the case when the STNO output signal is only several times higher than noise.« less

Multiplexed lateral flow biosensors: Technological advances for radically improving point-of-care diagnoses.

PubMed

Li, Jia; Macdonald, Joanne

2016-09-15

Lateral flow biosensors are a leading technology in point-of-care diagnostics due to their simplicity, rapidness and low cost. Their primacy in this arena continues through technological breakthroughs such as multiplexing: the detection of more than one biomarker in a single assay. Multiplexing capacity is critical for improving diagnostic efficiency, enhancing the diagnostic precision for specific diseases and reducing diagnostic cost. Here we review, for the first time, the various types and strategies employed for creating multiplexed lateral flow biosensors. These are classified into four main categories in terms of specific application or multiplexing level, namely linear, parameter, spatial and conceptual. We describe the practical applications and implications for each approach and compare their advantages and disadvantages. Importantly, multiplexing is still subject to limitations of the traditional lateral flow biosensor, such as sensitivity and specificity. However, by pushing the limitations of the traditional medium into the multiplex arena, several technological breakthroughs are emerging with novel solutions that further expand the utility of lateral flow biosensing for point-of-care applications. Copyright © 2016 Elsevier B.V. All rights reserved.

Some current applications, limitations and future perspectives of lactic acid bacteria as probiotics

PubMed Central

Evivie, Smith Etareri; Huo, Gui-Cheng; Igene, John Oamen; Bian, Xin

2017-01-01

ABSTRACT Several mechanism and non-mechanism-based studies supporting the claim that lactic acid bacteria (LAB) strains confer health benefits and play immune-modulatory roles were examined in this review. Probiotic applications of LAB on global burdens such as obesity and type-2 diabetes were discussed as well as the use of yoghurt and ice cream as important vehicles to convey several beneficial LAB strains. Probiotic and symbiotic dairy products may be used in the nearest future to treat a variety of health disorders. Current studies suggest that lactic acid bacteria possess anti-obesity and anti-diabetic propensities on their hosts and thus can play a crucial role in human health care. Research in the rheological and physicochemical properties of ice cream as well as its applications are also on the increase. These applications face certain hurdles including technological (for less developed countries), consumer acceptability of new functional foods may be influenced by culture, ethics or religion. There is need for more studies on the genetic basis for probiotic properties which will give further understanding regarding novel manipulation skills and applicability in nutrition and health sectors. More studies confirming the direct effects of probiotic LABs in lowering the spread of food-borne and other pathogens are also anticipated. PMID:28659729

The use of concept mapping in measurement development and evaluation: Application and future directions.

PubMed

Rosas, Scott R; Ridings, John W

2017-02-01

The past decade has seen an increase of measurement development research in social and health sciences that featured the use of concept mapping as a core technique. The purpose, application, and utility of concept mapping have varied across this emerging literature. Despite the variety of uses and range of outputs, little has been done to critically review how researchers have approached the application of concept mapping in the measurement development and evaluation process. This article focuses on a review of the current state of practice regarding the use of concept mapping as methodological tool in this process. We systematically reviewed 23 scale or measure development and evaluation studies, and detail the application of concept mapping in the context of traditional measurement development and psychometric testing processes. Although several limitations surfaced, we found several strengths in the contemporary application of the method. We determined concept mapping provides (a) a solid method for establishing content validity, (b) facilitates researcher decision-making, (c) insight into target population perspectives that are integrated a priori, and (d) a foundation for analytical and interpretative choices. Based on these results, we outline how concept mapping can be situated in the measurement development and evaluation processes for new instrumentation. Copyright © 2016 Elsevier Ltd. All rights reserved.

Digital micromirror devices: principles and applications in imaging.

PubMed

Bansal, Vivek; Saggau, Peter

2013-05-01

A digital micromirror device (DMD) is an array of individually switchable mirrors that can be used in many advanced optical systems as a rapid spatial light modulator. With a DMD, several implementations of confocal microscopy, hyperspectral imaging, and fluorescence lifetime imaging can be realized. The DMD can also be used as a real-time optical processor for applications such as the programmable array microscope and compressive sensing. Advantages and disadvantages of the DMD for these applications as well as methods to overcome some of the limitations will be discussed in this article. Practical considerations when designing with the DMD and sample optical layouts of a completely DMD-based imaging system and one in which acousto-optic deflectors (AODs) are used in the illumination pathway are also provided.

System Integration - A Major Step toward Lab on a Chip

PubMed Central

2011-01-01

Microfluidics holds great promise to revolutionize various areas of biological engineering, such as single cell analysis, environmental monitoring, regenerative medicine, and point-of-care diagnostics. Despite the fact that intensive efforts have been devoted into the field in the past decades, microfluidics has not yet been adopted widely. It is increasingly realized that an effective system integration strategy that is low cost and broadly applicable to various biological engineering situations is required to fully realize the potential of microfluidics. In this article, we review several promising system integration approaches for microfluidics and discuss their advantages, limitations, and applications. Future advancements of these microfluidic strategies will lead toward translational lab-on-a-chip systems for a wide spectrum of biological engineering applications. PMID:21612614

Algorithms for Lightweight Key Exchange †

PubMed Central

Santonja, Juan; Zamora, Antonio

2017-01-01

Public-key cryptography is too slow for general purpose encryption, with most applications limiting its use as much as possible. Some secure protocols, especially those that enable forward secrecy, make a much heavier use of public-key cryptography, increasing the demand for lightweight cryptosystems that can be implemented in low powered or mobile devices. This performance requirements are even more significant in critical infrastructure and emergency scenarios where peer-to-peer networks are deployed for increased availability and resiliency. We benchmark several public-key key-exchange algorithms, determining those that are better for the requirements of critical infrastructure and emergency applications and propose a security framework based on these algorithms and study its application to decentralized node or sensor networks. PMID:28654006

Safer energetic materials by a nanotechnological approach

NASA Astrophysics Data System (ADS)

Siegert, Benny; Comet, Marc; Spitzer, Denis

2011-09-01

Energetic materials - explosives, thermites, populsive powders - are used in a variety of military and civilian applications. Their mechanical and electrostatic sensitivity is high in many cases, which can lead to accidents during handling and transport. These considerations limit the practical use of some energetic materials despite their good performance. For industrial applications, safety is one of the main criteria for selecting energetic materials. The sensitivity has been regarded as an intrinsic property of a substance for a long time. However, in recent years, several approaches to lower the sensitivity of a given substance, using nanotechnology and materials engineering, have been described. This feature article gives an overview over ways to prepare energetic (nano-)materials with a lower sensitivity.Energetic materials - explosives, thermites, populsive powders - are used in a variety of military and civilian applications. Their mechanical and electrostatic sensitivity is high in many cases, which can lead to accidents during handling and transport. These considerations limit the practical use of some energetic materials despite their good performance. For industrial applications, safety is one of the main criteria for selecting energetic materials. The sensitivity has been regarded as an intrinsic property of a substance for a long time. However, in recent years, several approaches to lower the sensitivity of a given substance, using nanotechnology and materials engineering, have been described. This feature article gives an overview over ways to prepare energetic (nano-)materials with a lower sensitivity. Electronic supplementary information (ESI) available: Experimental details for the preparation of the V2O5@CNF/Al nanothermite; X-ray diffractogram of the V2O5@CNF/Al combustion residue; installation instructions and source code for the nt-timeline program. See DOI: 10.1039/c1nr10292c

Determination and evaluation of acceptable force limits in single-digit tasks.

PubMed

Nussbaum, Maury A; Johnson, Hope

2002-01-01

Acceptable limits derived from psychophysical methodologies have been proposed, measured, and employed in a range of applications. There is little existing work, however, on such limits for single-digit exertions and relatively limited evidence on several fundamental issues related to data collection and processing of a sequence of self-regulated exertion levels. An experimental study was conducted using 14 male and 10 female participants (age range 18-31 years) from whom maximal voluntary exertions and maximal acceptable limits (MALs) were obtained using the index finger and thumb. Moderate to high levels of consistency were found for both measures between sessions separated by one day. Single MAL values, determined from a time series of exertions, were equivalent across three divergent processing methods and between values obtained from 5- and 25-min samples. A critical interpretation of these and earlier results supports continued use of acceptable limits but also suggests that they should be used with some caution and not equated with safe limits. This research can be applied toward future development of exertion limits based on perceived acceptability.

Modeling and characterization of dye-doped guest-host liquid crystal eyewear

NASA Astrophysics Data System (ADS)

Coutino, Pedro Coutino

This thesis explores the use of dye-doped guest-host liquid crystals in variable transmission eyewear devices that protect against rapid and abrupt changes in lighting conditions. Some of their unique characteristics such as millisecond time response, low power consumption, fail-safe operation, and wide color palette make them the only available technology that meets the basic requirements for fast, adaptative eyewear applications. Despite these unique features, there are limitations in the technology which have hindered its use for more advanced eyewear applications. It is the aim of this dissertation to explore these limitations and provide experimental and numerical characterization tools necessary to surpass them. First, several techniques are described to evaluate materials and devices performance in terms of their photopic transmission, haze, birefringence, and distortion. The results are used to demonstrate that by choosing and combining the right materials, it is possible to improve the optical quality of the eyewear. Then, a simulation instrument which combines and integrates all the necessary elements to model the electro-optical response of dye-doped guest-host liquid crystal eyewear was constructed. This program is capable of reproducing with high accuracy experimental results, to predict the performance of devices, and to mimic the spectral curve of a target color. Numerical experiments were performed to study some of the most common limitations of the e-Tint mode or single cell technology including photopic transmission window, and polarization dependence and demonstrate that optimizing parameters such as birefringence, d/p, and concentration of dyes helps to overcome these limitations and enhance system performance. A guest-host double cell system is proposed as a new alternative mode for most advanced eyewear applications. Particular attention was placed on a switchable crossed polarizers configuration which offered superior optical characteristics such as extremely low polarization dependence and increased transmission window. Simulations showed that the same effect can be obtained for other non-zero d/p values, by proper choice of chirality and configuration. Furthermore, a unique four-color eyewear was designed by combining the absorption properties of individual cells. Finally, several state-of-the-art military and commercial dye-doped guest-host eyewear applications which make use of all the results obtained during this dissertation are presented.

Microbial Fuels Cell-Based Biosensor for Toxicity Detection: A Review

PubMed Central

Zhou, Tuoyu; Han, Huawen; Liu, Pu; Xiong, Jian; Tian, Fake; Li, Xiangkai

2017-01-01

With the unprecedented deterioration of environmental quality, rapid recognition of toxic compounds is paramount for performing in situ real-time monitoring. Although several analytical techniques based on electrochemistry or biosensors have been developed for the detection of toxic compounds, most of them are time-consuming, inaccurate, or cumbersome for practical applications. More recently, microbial fuel cell (MFC)-based biosensors have drawn increasing interest due to their sustainability and cost-effectiveness, with applications ranging from the monitoring of anaerobic digestion process parameters (VFA) to water quality detection (e.g., COD, BOD). When a MFC runs under correct conditions, the voltage generated is correlated with the amount of a given substrate. Based on this linear relationship, several studies have demonstrated that MFC-based biosensors could detect heavy metals such as copper, chromium, or zinc, as well as organic compounds, including p-nitrophenol (PNP), formaldehyde and levofloxacin. Both bacterial consortia and single strains can be used to develop MFC-based biosensors. Biosensors with single strains show several advantages over systems integrating bacterial consortia, such as selectivity and stability. One of the limitations of such sensors is that the detection range usually exceeds the actual pollution level. Therefore, improving their sensitivity is the most important for widespread application. Nonetheless, MFC-based biosensors represent a promising approach towards single pollutant detection. PMID:28956857

Microbial Fuels Cell-Based Biosensor for Toxicity Detection: A Review.

PubMed

Zhou, Tuoyu; Han, Huawen; Liu, Pu; Xiong, Jian; Tian, Fake; Li, Xiangkai

2017-09-28

With the unprecedented deterioration of environmental quality, rapid recognition of toxic compounds is paramount for performing in situ real-time monitoring. Although several analytical techniques based on electrochemistry or biosensors have been developed for the detection of toxic compounds, most of them are time-consuming, inaccurate, or cumbersome for practical applications. More recently, microbial fuel cell (MFC)-based biosensors have drawn increasing interest due to their sustainability and cost-effectiveness, with applications ranging from the monitoring of anaerobic digestion process parameters (VFA) to water quality detection (e.g., COD, BOD). When a MFC runs under correct conditions, the voltage generated is correlated with the amount of a given substrate. Based on this linear relationship, several studies have demonstrated that MFC-based biosensors could detect heavy metals such as copper, chromium, or zinc, as well as organic compounds, including p -nitrophenol (PNP), formaldehyde and levofloxacin. Both bacterial consortia and single strains can be used to develop MFC-based biosensors. Biosensors with single strains show several advantages over systems integrating bacterial consortia, such as selectivity and stability. One of the limitations of such sensors is that the detection range usually exceeds the actual pollution level. Therefore, improving their sensitivity is the most important for widespread application. Nonetheless, MFC-based biosensors represent a promising approach towards single pollutant detection.

Variable Complexity Structural Optimization of Shells

NASA Technical Reports Server (NTRS)

Haftka, Raphael T.; Venkataraman, Satchi

1999-01-01

Structural designers today face both opportunities and challenges in a vast array of available analysis and optimization programs. Some programs such as NASTRAN, are very general, permitting the designer to model any structure, to any degree of accuracy, but often at a higher computational cost. Additionally, such general procedures often do not allow easy implementation of all constraints of interest to the designer. Other programs, based on algebraic expressions used by designers one generation ago, have limited applicability for general structures with modem materials. However, when applicable, they provide easy understanding of design decisions trade-off. Finally, designers can also use specialized programs suitable for designing efficiently a subset of structural problems. For example, PASCO and PANDA2 are panel design codes, which calculate response and estimate failure much more efficiently than general-purpose codes, but are narrowly applicable in terms of geometry and loading. Therefore, the problem of optimizing structures based on simultaneous use of several models and computer programs is a subject of considerable interest. The problem of using several levels of models in optimization has been dubbed variable complexity modeling. Work under NASA grant NAG1-2110 has been concerned with the development of variable complexity modeling strategies with special emphasis on response surface techniques. In addition, several modeling issues for the design of shells of revolution were studied.

Variable Complexity Structural Optimization of Shells

NASA Technical Reports Server (NTRS)

Haftka, Raphael T.; Venkataraman, Satchi

1998-01-01

Structural designers today face both opportunities and challenges in a vast array of available analysis and optimization programs. Some programs such as NASTRAN, are very general, permitting the designer to model any structure, to any degree of accuracy, but often at a higher computational cost. Additionally, such general procedures often do not allow easy implementation of all constraints of interest to the designer. Other programs, based on algebraic expressions used by designers one generation ago, have limited applicability for general structures with modem materials. However, when applicable, they provide easy understanding of design decisions trade-off. Finally, designers can also use specialized programs suitable for designing efficiently a subset of structural problems. For example, PASCO and PANDA2 are panel design codes, which calculate response and estimate failure much more efficiently than general-purpose codes, but are narrowly applicable in terms of geometry and loading. Therefore, the problem of optimizing structures based on simultaneous use of several models and computer programs is a subject of considerable interest. The problem of using several levels of models in optimization has been dubbed variable complexity modeling. Work under NASA grant NAG1-1808 has been concerned with the development of variable complexity modeling strategies with special emphasis on response surface techniques. In addition several modeling issues for the design of shells of revolution were studied.

Significance of Antioxidant Potential of Plants and its Relevance to Therapeutic Applications

PubMed Central

Kasote, Deepak M.; Katyare, Surendra S.; Hegde, Mahabaleshwar V.; Bae, Hanhong

2015-01-01

Oxidative stress has been identified as the root cause of the development and progression of several diseases. Supplementation of exogenous antioxidants or boosting endogenous antioxidant defenses of the body is a promising way of combating the undesirable effects of reactive oxygen species (ROS) induced oxidative damage. Plants have an innate ability to biosynthesize a wide range of non-enzymatic antioxidants capable of attenuating ROS- induced oxidative damage. Several in vitro methods have been used to screen plants for their antioxidant potential, and in most of these assays they revealed potent antioxidant activity. However, prior to confirming their in vivo therapeutic efficacy, plant antioxidants have to pass through several physiopharmacological processes. Consequently, the findings of in vitro and in vivo antioxidant potential assessment studies are not always the same. Nevertheless, the results of in vitro assays have been irrelevantly extrapolated to the therapeutic application of plant antioxidants without undertaking sufficient in vivo studies. Therefore, we have briefly reviewed the physiology and redox biology of both plants and humans to improve our understanding of plant antioxidants as therapeutic entities. The applications and limitations of antioxidant activity measurement assays were also highlighted to identify the precise path to be followed for future research in the area of plant antioxidants. PMID:26157352

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

Sale, K

Several approaches to ASP performance can be contemplated. Perhaps the ideal would be a full cost/benefit analysis (which is probably utterly infeasible). Another approach would be a test-based figure-of-merit (FOM), this approach has the virtue of being quantitative and the challenge that each customer and application would be characterized by a different FOM. The alternative proposed here is an approach that uses information about the limits of detection of real instruments to support informed judgments.

An Overview on Additive Manufacturing of Polymers

NASA Astrophysics Data System (ADS)

Jasiuk, Iwona; Abueidda, Diab W.; Kozuch, Christopher; Pang, Siyuan; Su, Frances Y.; McKittrick, Joanna

2018-03-01

We present an overview on additive manufacturing (AM), also called three-dimensional printing, with a focus on polymers. First, we introduce the AM concept. Next, we outline several AM processes, including their advantages and limitations, and list common polymers that are used in commercial printers. Then, we state various AM applications and present two examples. We conclude with a global view of the AM field, its challenges, and future directions.

Modification of the flow pass method as applied to problems of chemistry of planet atmospheres

NASA Technical Reports Server (NTRS)

Parshev, V. A.

1980-01-01

It was shown that the modified flow pass method possesses considerable effectiveness, both in the case when the coefficient of diffusion changes severely in the examined region and in the case when diffusion is the prevalent process, as compared with chemical reactions. The case when a regular pass proves inapplicable, or applicable in a limited interval of the decisive parameters, was examined.

The application of absolute quantitative (1)H NMR spectroscopy in drug discovery and development.

PubMed

Singh, Suruchi; Roy, Raja

2016-07-01

The identification of a drug candidate and its structural determination is the most important step in the process of the drug discovery and for this, nuclear magnetic resonance (NMR) is one of the most selective analytical techniques. The present review illustrates the various perspectives of absolute quantitative (1)H NMR spectroscopy in drug discovery and development. It deals with the fundamentals of quantitative NMR (qNMR), the physiochemical properties affecting qNMR, and the latest referencing techniques used for quantification. The precise application of qNMR during various stages of drug discovery and development, namely natural product research, drug quantitation in dosage forms, drug metabolism studies, impurity profiling and solubility measurements is elaborated. To achieve this, the authors explore the literature of NMR in drug discovery and development between 1963 and 2015. It also takes into account several other reviews on the subject. qNMR experiments are used for drug discovery and development processes as it is a non-destructive, versatile and robust technique with high intra and interpersonal variability. However, there are several limitations also. qNMR of complex biological samples is incorporated with peak overlap and a low limit of quantification and this can be overcome by using hyphenated chromatographic techniques in addition to NMR.

Estimation of effective temperatures in a quantum annealer: Towards deep learning applications

NASA Astrophysics Data System (ADS)

Realpe-Gómez, John; Benedetti, Marcello; Perdomo-Ortiz, Alejandro

Sampling is at the core of deep learning and more general machine learning applications; an increase in its efficiency would have a significant impact across several domains. Recently, quantum annealers have been proposed as a potential candidate to speed up these tasks, but several limitations still bar them from being used effectively. One of the main limitations, and the focus of this work, is that using the device's experimentally accessible temperature as a reference for sampling purposes leads to very poor correlation with the Boltzmann distribution it is programmed to sample from. Based on quantum dynamical arguments, one can expect that if the device indeed happens to be sampling from a Boltzmann-like distribution, it will correspond to one with an instance-dependent effective temperature. Unless this unknown temperature can be unveiled, it might not be possible to effectively use a quantum annealer for Boltzmann sampling processes. In this work, we propose a strategy to overcome this challenge with a simple effective-temperature estimation algorithm. We provide a systematic study assessing the impact of the effective temperatures in the quantum-assisted training of Boltzmann machines, which can serve as a building block for deep learning architectures. This work was supported by NASA Ames Research Center.

Wireless, High-Bandwidth Recordings from Non-Human Primate Motor Cortex using a Scalable 16-Ch Implantable Microsystem

PubMed Central

Borton, David A.; Song, Yoon-Kyu; Patterson, William R.; Bull, Christopher W.; Park, Sunmee; Laiwalla, Farah; Donoghue, John P.; Nurmikko, Arto V.

2013-01-01

A multitude of neuroengineering challenges exist today in creating practical, chronic multichannel neural recording systems for primate research and human clinical application. Specifically, a) the persistent wired connections limit patient mobility from the recording system, b) the transfer of high bandwidth signals to external (even distant) electronics normally forces premature data reduction, and c) the chronic susceptibility to infection due to the percutaneous nature of the implants all severely hinder the success of neural prosthetic systems. Here we detail one approach to overcome these limitations: an entirely implantable, wirelessly communicating, integrated neural recording microsystem, dubbed the Brain Implantable Chip (BIC). PMID:19964128

Use of application containers and workflows for genomic data analysis

PubMed Central

Schulz, Wade L.; Durant, Thomas J. S.; Siddon, Alexa J.; Torres, Richard

2016-01-01

Background: The rapid acquisition of biological data and development of computationally intensive analyses has led to a need for novel approaches to software deployment. In particular, the complexity of common analytic tools for genomics makes them difficult to deploy and decreases the reproducibility of computational experiments. Methods: Recent technologies that allow for application virtualization, such as Docker, allow developers and bioinformaticians to isolate these applications and deploy secure, scalable platforms that have the potential to dramatically increase the efficiency of big data processing. Results: While limitations exist, this study demonstrates a successful implementation of a pipeline with several discrete software applications for the analysis of next-generation sequencing (NGS) data. Conclusions: With this approach, we significantly reduced the amount of time needed to perform clonal analysis from NGS data in acute myeloid leukemia. PMID:28163975

An integrated multi-sensor fusion-based deep feature learning approach for rotating machinery diagnosis

NASA Astrophysics Data System (ADS)

Liu, Jie; Hu, Youmin; Wang, Yan; Wu, Bo; Fan, Jikai; Hu, Zhongxu

2018-05-01

The diagnosis of complicated fault severity problems in rotating machinery systems is an important issue that affects the productivity and quality of manufacturing processes and industrial applications. However, it usually suffers from several deficiencies. (1) A considerable degree of prior knowledge and expertise is required to not only extract and select specific features from raw sensor signals, and but also choose a suitable fusion for sensor information. (2) Traditional artificial neural networks with shallow architectures are usually adopted and they have a limited ability to learn the complex and variable operating conditions. In multi-sensor-based diagnosis applications in particular, massive high-dimensional and high-volume raw sensor signals need to be processed. In this paper, an integrated multi-sensor fusion-based deep feature learning (IMSFDFL) approach is developed to identify the fault severity in rotating machinery processes. First, traditional statistics and energy spectrum features are extracted from multiple sensors with multiple channels and combined. Then, a fused feature vector is constructed from all of the acquisition channels. Further, deep feature learning with stacked auto-encoders is used to obtain the deep features. Finally, the traditional softmax model is applied to identify the fault severity. The effectiveness of the proposed IMSFDFL approach is primarily verified by a one-stage gearbox experimental platform that uses several accelerometers under different operating conditions. This approach can identify fault severity more effectively than the traditional approaches.

Designing Mobile Applications for Emergency Response: Citizens Acting as Human Sensors.

PubMed

Romano, Marco; Onorati, Teresa; Aedo, Ignacio; Diaz, Paloma

2016-03-19

When an emergency occurs, citizens can be a helpful support for the operation centers involved in the response activities. As witnesses to a crisis, they initially can share updated and detailed information about what is going on. Moreover, thanks to the current technological evolution people are able to quickly and easily gather rich information and transmit it through different communication channels. Indeed, modern mobile devices embed several sensors such as GPS receivers, Wi-Fi, accelerometers or cameras that can transform users into well-equipped human sensors. For these reasons, emergency organizations and small and medium enterprises have demonstrated a growing interest in developing smart applications for reporting any exceptional circumstances. In this paper, we present a practical study about this kind of applications for identifying both limitations and common features. Based on a study of relevant existent contributions in this area and our personal direct experience in developing and evaluating emergency management solutions, our aim is to propose several findings about how to design effective and efficient mobile emergency notification applications. For this purpose we have exploited the basic sensors of modern mobile devices and the users' aptitude for using them. The evaluation consists of a practical and a theoretical part. In the practical part, we have simulated a traffic accident as closely as possible to a real scenario, with a victim lying on the ground near a car in the middle of a street. For the theoretical part, we have interviewed some emergency experts for collecting their opinions about the utility of the proposed solution. Results from this evaluation phase confirm the positive impact that EN application have for both operators' and citizens' perspective. Moreover, we collected several findings useful for future design challenges in the same area, as shown in the final redesign of the proposed application.

Microbial electrolysis cells turning to be versatile technology: recent advances and future challenges.

PubMed

Zhang, Yifeng; Angelidaki, Irini

2014-06-01

Microbial electrolysis cells (MECs) are an electricity-mediated microbial bioelectrochemical technology, which is originally developed for high-efficiency biological hydrogen production from waste streams. Compared to traditional biological technologies, MECs can overcome thermodynamic limitations and achieve high-yield hydrogen production from wide range of organic matters at relatively mild conditions. This approach greatly reduces the electric energy cost for hydrogen production in contrast to direct water electrolysis. In addition to hydrogen production, MECs may also support several energetically unfavorable biological/chemical reactions. This unique advantage of MECs has led to several alternative applications such as chemicals synthesis, recalcitrant pollutants removal, resources recovery, bioelectrochemical research platform and biosensors, which have greatly broaden the application scopes of MECs. MECs are becoming a versatile platform technology and offer a new solution for emerging environmental issues related to waste streams treatment and energy and resource recovery. Different from previous reviews that mainly focus on hydrogen production, this paper provides an up-to-date review of all the new applications of MECs and their resulting performance, current challenges and prospects of future. Copyright © 2014 Elsevier Ltd. All rights reserved.

Semiempirical Quantum Mechanical Methods for Noncovalent Interactions for Chemical and Biochemical Applications

PubMed Central

2016-01-01

Semiempirical (SE) methods can be derived from either Hartree–Fock or density functional theory by applying systematic approximations, leading to efficient computational schemes that are several orders of magnitude faster than ab initio calculations. Such numerical efficiency, in combination with modern computational facilities and linear scaling algorithms, allows application of SE methods to very large molecular systems with extensive conformational sampling. To reliably model the structure, dynamics, and reactivity of biological and other soft matter systems, however, good accuracy for the description of noncovalent interactions is required. In this review, we analyze popular SE approaches in terms of their ability to model noncovalent interactions, especially in the context of describing biomolecules, water solution, and organic materials. We discuss the most significant errors and proposed correction schemes, and we review their performance using standard test sets of molecular systems for quantum chemical methods and several recent applications. The general goal is to highlight both the value and limitations of SE methods and stimulate further developments that allow them to effectively complement ab initio methods in the analysis of complex molecular systems. PMID:27074247

Ablative therapies: Advantages and disadvantages of radiofrequency, cryotherapy, microwave and electroporation methods, or how to choose the right method for an individual patient?

PubMed

Seror, O

2015-06-01

Several ablation techniques are currently available. Except for electroporation, all of these methods cause fatal damage at a cellular level and irreversible architectural deconstruction at a tissue level by thermal effects. Ablation of a tumor using one of these techniques, whether thermal or otherwise, requires applicators to be positioned from which the energy is delivered in situ. Some techniques, however, require several applicators to be inserted (multibipolar radiofrequency, cryotherapy and electroporation) whereas a single applicator is often sufficient with other technologies (monopolar radiofrequency and microwave). These methods are conceptually very similar but are distinguished from each other in practice through the technologies they use. It is essential to understand these differences as they influence the advantages and limitations of each of the techniques. There is no such thing as the perfect multifunctional ablation device and choice is dictated on an individual patient basis depending on the aim of treatment, which itself depends on each patient's clinical situation. Copyright © 2015 Éditions françaises de radiologie. Published by Elsevier Masson SAS. All rights reserved.

Nanomedicines in gastroenterology and hepatology.

PubMed

Lamprecht, Alf

2015-04-01

Nanoscale systems are currently under investigation for multiple different diagnostic and therapeutic applications. These systems can be used to identify pathologically changed tissues or to selectively deliver drugs to these sites; both applications have an extremely high potential to ameliorate therapeutic outcomes for patients. Tissues as well as single cells can be targeted because of the small size of these systems, which enables enhanced diagnosis and increased specificity of therapy. Drug loads can be delivered directly to the site of action, which can result in a reduction in incidence and severity of adverse systemic effects. Several nano-based platform technologies are currently under investigation for use in therapeutic approaches, mainly for anti-inflammatory and anti-cancer therapies. Although many nanoscale systems show promising therapeutic outcomes in preclinical studies, only a limited number are ready for clinical use. This Review will discuss the diverse nanomaterials currently available and the first specific uses for select gastroenterological and hepatological pathologies. The discussion of diagnostic and therapeutic applications will consider realities of market introduction of these sometimes very complex systems in light of remaining regulatory challenges and hurdles for industrial production.

Creating durable and esthetic gingival anatomy on a polyoxymethylene overdenture by using a chairside procedure.

PubMed

Login, Gary R

2017-07-01

Snap-On Smile (DenMat) appliances are tooth-borne overdentures used for a variety of temporary esthetic applications. However, their benefit can be limited in patients with high smile lines and altered gingival architecture because the teeth look too large. In this report, the author shows the chairside application of a silicone denture reline material used to recreate gingival anatomy on an overdenture fabricated from crystallized acetyl resin, the material used in a Snap-On Smile appliance. The author shows the gingival application's durability of greater than 2 years in a 78-year-old patient with multiple missing teeth and a severe mandibular ridge deformity. The author tested several commonly available denture reline materials and their bonding agents, which are known to bond to acrylic resin but have not been shown to bond to crystallized acetyl resin. The author observed no candida colonization during the 2-year reporting period. The author presents a simple and durable chairside technique to reproduce gingival tissue esthetically on Snap-On Smile appliances. Copyright © 2017 American Dental Association. Published by Elsevier Inc. All rights reserved.

Acousto-optic replication of ultrashort laser pulses

NASA Astrophysics Data System (ADS)

Yushkov, Konstantin B.; Molchanov, Vladimir Ya.; Ovchinnikov, Andrey V.; Chefonov, Oleg V.

2017-10-01

Precisely controlled sequences of ultrashort laser pulses are required in various scientific and engineering applications. We developed a phase-only acousto-optic pulse shaping method for replication of ultrashort laser pulses in a TW laser system. A sequence of several Fourier-transform-limited pulses is generated from a single femtosecond laser pulse by means of applying a piecewise linear phase modulation over the whole emission spectrum. Analysis demonstrates that the main factor which limits maximum delay between the pulse replicas is spectral resolution of the acousto-optic dispersive delay line used for pulse shaping. In experiments with a Cr:forsterite laser system, we obtained delays from 0.3 to 3.5 ps between two replicas of 190 fs transform-limited pulses at the central wavelength of laser emission, 1230 nm.

Effects and effectiveness of telemedicine.

PubMed

Grigsby, J; Kaehny, M M; Sandberg, E J; Schlenker, R E; Shaughnessy, P W

1995-01-01

The use of telemedicine has recently undergone rapid growth and proliferation. Although the feasibility of many applications has been tested for nearly 30 years, data concerning the costs, effects, and effectiveness of telemedicine are limited. Consequently, the development of a strategy for coverage, payment, and utilization policy has been hindered. Telemedicine continues to expand, and pressure for policy development increases in the context of Federal budget cuts and major changes in health service financing. This article reviews the literature on the effects and medical effectiveness of telemedicine. It concludes with several recommendations for research, followed by a discussion of several specific questions, the answers to which might have a bearing on policy development.

DbMap: improving database interoperability issues in medical software using a simple, Java-Xml based solution.

PubMed Central

Karadimas, H.; Hemery, F.; Roland, P.; Lepage, E.

2000-01-01

In medical software development, the use of databases plays a central role. However, most of the databases have heterogeneous encoding and data models. To deal with these variations in the application code directly is error-prone and reduces the potential reuse of the produced software. Several approaches to overcome these limitations have been proposed in the medical database literature, which will be presented. We present a simple solution, based on a Java library, and a central Metadata description file in XML. This development approach presents several benefits in software design and development cycles, the main one being the simplicity in maintenance. PMID:11079915

Prismatic sealed nickel-cadmium batteries utilizing fiber structured electrodes. II - Applications as a maintenance free aircraft battery

NASA Astrophysics Data System (ADS)

Anderman, Menahem; Benczur-Urmossy, Gabor; Haschka, Friedrich

Test data on prismatic sealed Ni-Cd batteries utilizing fiber structured electrodes (sealed FNC) is discussed. It is shown that, under a voltage limited charging scheme, the charge acceptance of the sealed FNC battery is far superior to that of the standard vented aircraft Ni-Cd batteries. This results in the sealed FNC battery maintaining its capacity over several thousand cycles without any need for electrical conditioning or water topping. APU start data demonstrate superior power capabilities over existing technologies. Performance at low temperature is presented. Abuse test results reveal a safe fail mechanism even under severe electrical abuse.

Use of decision support systems as a drought management tool

USGS Publications Warehouse

Frevert, D.; Lins, H.; ,

2005-01-01

Droughts present a unique challenge to water managers throughout the world and the current drought in the western United States is taxing facilities to the limit. Coping with this severe drought requires state of the art decision support systems including efficient and accurate hydrologic process models, detailed hydrologic data bases and effective river systems management modeling frameworks. This paper will outline a system of models developed by the Bureau of Reclamation, the US Geological Survey, the University of Colorado and a number of other governmental and university partners. The application of the technology to drought management in several key western river basins will be discussed.

Ultra fine grained Ti prepared by severe plastic deformation

NASA Astrophysics Data System (ADS)

Lukáč, F.; Čížek, J.; Knapp, J.; Procházka, I.; Zháňal, P.; Islamgaliev, R. K.

2016-01-01

The positron annihilation spectroscopy was employed for characterisation of defects in pure Ti with ultra fine grained (UFG) structure. UFG Ti samples were prepared by two techniques based on severe plastic deformation (SPD): (i) high pressure torsion (HPT) and (ii) equal channel angular pressing (ECAP). Although HPT is the most efficient technique for grain refinement, the size of HPT-deformed specimens is limited. On the other hand, ECAP is less efficient in grain refinement but enables to produce larger samples more suitable for industrial applications. Characterisation of defects by positron annihilation spectroscopy was accompanied by hardness testing in order to monitor the development of mechanical properties of UFG Ti.

Two alternative ways for solving the coordination problem in multilevel optimization

NASA Technical Reports Server (NTRS)

Sobieszczanski-Sobieski, Jaroslaw

1991-01-01

Two techniques for formulating the coupling between levels in multilevel optimization by linear decomposition, proposed as improvements over the original formulation, now several years old, that relied on explicit equality constraints which were shown by application experience as occasionally causing numerical difficulties. The two new techniques represent the coupling without using explicit equality constraints, thus avoiding the above diffuculties and also reducing computational cost of the procedure. The old and new formulations are presented in detail and illustrated by an example of a structural optimization. A generic version of the improved algorithm is also developed for applications to multidisciplinary systems not limited to structures.

A Review of the Application of Body-on-a-Chip for Drug Test and Its Latest Trend of Incorporating Barrier Tissue.

PubMed

Jin, Haoyi; Yu, Yanqiu

2016-10-01

High-quality preclinical bioassay models are essential for drug research and development. We reviewed the emerging body-on-a-chip technology, which serves as a promising model to overcome the limitations of traditional bioassay models, and introduced existing models of body-on-a-chip, their constitutional details, application for drug testing, and individual features of these models. We put special emphasis on the latest trend in this field of incorporating barrier tissue into body-on-a-chip and discussed several remaining challenges of current body-on-a-chip. © 2015 Society for Laboratory Automation and Screening.

Learning from Bacteriophages - Advantages and Limitations of Phage and Phage-Encoded Protein Applications

PubMed Central

Drulis-Kawa, Zuzanna; Majkowska-Skrobek, Grażyna; Maciejewska, Barbara; Delattre, Anne-Sophie; Lavigne, Rob

2012-01-01

The emergence of bacteria resistance to most of the currently available antibiotics has become a critical therapeutic problem. The bacteria causing both hospital and community-acquired infections are most often multidrug resistant. In view of the alarming level of antibiotic resistance between bacterial species and difficulties with treatment, alternative or supportive antibacterial cure has to be developed. The presented review focuses on the major characteristics of bacteriophages and phage-encoded proteins affecting their usefulness as antimicrobial agents. We discuss several issues such as mode of action, pharmacodynamics, pharmacokinetics, resistance and manufacturing aspects of bacteriophages and phage-encoded proteins application. PMID:23305359

The effect of plasma density and emitter geometry on space charge limits for field emitter array electron charge emission into a space plasma

NASA Astrophysics Data System (ADS)

Morris, Dave; Gilchrist, Brian; Gallimore, Alec

2001-02-01

Field Emitter Array Cathodes (FEACs) are a new technology being developed for several potential spacecraft electron emission and charge control applications. Instead of a single hot (i.e., high powered) emitter, or a gas dependant plasma contactor, FEAC systems consist of many (hundreds or thousands) of small (micron level) cathode/gate pairs printed on a semiconductor wafer that effect cold field emission at relatively low voltages. Each individual cathode emits only micro-amp level currents, but a functional array is capable of amp/cm2 current densities. It is hoped that thus FEAC offers the possibility of a relatively low-power, simple to integrate, and inexpensive technique for the high level of current emissions that are required for an electrodynamic tether (EDT) propulsion mission. Space charge limits are a significant concern for the EDT application. Vacuum chamber tests and PIC simulations are being performed at the University of Michigan Plasmadynamics and Electric Propulsion Laboratory and Space Physics Research Laboratory to determine the effect of plasma density and emitter geometry on space charge limitations. The results of this work and conclusions to date of how to best mitigate space charge limits will be presented. .

SciReader enables reading of medical content with instantaneous definitions.

PubMed

Gradie, Patrick R; Litster, Megan; Thomas, Rinu; Vyas, Jay; Schiller, Martin R

2011-01-25

A major problem patients encounter when reading about health related issues is document interpretation, which limits reading comprehension and therefore negatively impacts health care. Currently, searching for medical definitions from an external source is time consuming, distracting, and negatively impacts reading comprehension and memory of the material. SciReader was built as a Java application with a Flex-based front-end client. The dictionary used by SciReader was built by consolidating data from several sources and generating new definitions with a standardized syntax. The application was evaluated by measuring the percentage of words defined in different documents. A survey was used to test the perceived effect of SciReader on reading time and comprehension. We present SciReader, a web-application that simplifies document interpretation by allowing users to instantaneously view medical, English, and scientific definitions as they read any document. This tool reveals the definitions of any selected word in a small frame at the top of the application. SciReader relies on a dictionary of ~750,000 unique Biomedical and English word definitions. Evaluation of the application shows that it maps ~98% of words in several different types of documents and that most users tested in a survey indicate that the application decreases reading time and increases comprehension. SciReader is a web application useful for reading medical and scientific documents. The program makes jargon-laden content more accessible to patients, educators, health care professionals, and the general public.

Mechanical stability of the subtalar joint after lateral ligament sectioning and ankle brace application: a biomechanical experimental study.

PubMed

Kamiya, Tomoaki; Kura, Hideji; Suzuki, Daisuke; Uchiyama, Eiichi; Fujimiya, Mineko; Yamashita, Toshihiko

2009-12-01

The roles of each ligament supporting the subtalar joint have not been clarified despite several biomechanical studies. The effects of ankle braces on subtalar instability have not been shown. The ankle brace has a partial effect on restricting excessive motion of the subtalar joint. Controlled laboratory study. Ten normal fresh-frozen cadaveric specimens were used. The angular motions of the talus were measured via a magnetic tracking system. The specimens were tested while inversion and eversion forces, as well as internal and external rotation torques, were applied. The calcaneofibular ligament, cervical ligament, and interosseous talocalcaneal ligament were sectioned sequentially, and the roles of each ligament, as well as the stabilizing effects of the ankle brace, were examined. Complete sectioning of the ligaments increased the angle between the talus and calcaneus in the frontal plane to 51.7 degrees + or - 11.8 degrees compared with 35.7 degrees + or - 6.0 degrees in the intact state when inversion force was applied. There was a statistically significant difference in the angles between complete sectioning of the ligaments and after application of the brace (34.1 degrees + or - 7.3 degrees ) when inversion force was applied. On the other hand, significant differences in subtalar rotation were not found between complete sectioning of the ligaments and application of the brace when internal and external rotational torques were applied. The ankle brace limited inversion of the subtalar joint, but it did not restrict motion after application of internal or external rotational torques. In cases of severe ankle sprains involving the calcaneofibular ligament, cervical ligament, and interosseous talocalcaneal ligament injuries, application of an ankle brace might be less effective in limiting internal-external rotational instabilities than in cases of inversion instabilities in the subtalar joint. An improvement in the design of the brace is needed to restore better rotational stability in the subtalar joint.

Clinical application of adipose stem cells in plastic surgery.

PubMed

Kim, Yong-Jin; Jeong, Jae-Ho

2014-04-01

Adipose stem cells (ASCs) are a type of adult stem cells that share common characteristics with typical mesenchymal stem cells. In the last decade, ASCs have been shown to be a useful cell resource for tissue regeneration. The major role of regenerative medicine in this century is based on cell therapy in which ASCs hold a key position. Active research on this new type of adult stem cell has been ongoing and these cells now have several clinical applications, including fat grafting, overcoming wound healing difficulties, recovery from local tissue ischemia, and scar remodeling. The application of cultured cells will increase the efficiency of cell therapy. However, the use of cultured stem cells is strictly controlled by government regulation to ensure patient safety. Government regulation is a factor that can limit more versatile clinical application of ASCs. In this review, current clinical applications of ASCs in plastic surgery are introduced. Future stem cell applications in clinical field including culturing and banking of ASCs are also discussed in this review.

Optical fiber tips for biological applications: From light confinement, biosensing to bioparticles manipulation.

PubMed

Paiva, Joana S; Jorge, Pedro A S; Rosa, Carla C; Cunha, João P S

2018-05-01

The tip of an optical fiber has been considered an attractive platform in Biology. The simple cleaved end of an optical fiber can be machined, patterned and/or functionalized, acquiring unique properties enabling the exploitation of novel optical phenomena. Prompted by the constant need to measure and manipulate nanoparticles, the invention of the Scanning Near-field Optical Microscopy (SNOM) triggered the optimization and development of novel fiber tip microfabrication methods. In fact, the fiber tip was soon considered a key element in SNOM by confining light to sufficiently small extensions, challenging the diffraction limit. As result and in consequence of the newly proposed "Lab On Tip" concept, several geometries of fiber tips were applied in three main fields: imaging (in Microscopy/Spectroscopy), biosensors and micromanipulation (Optical Fiber Tweezers, OFTs). These are able to exert forces on microparticles, trap and manipulate them for relevant applications, as biomolecules mechanical study or protein aggregates unfolding. This review presents an overview of the main achievements, most impactful studies and limitations of fiber tip-based configurations within the above three fields, along the past 10 years. OFTs could be in future a valuable tool for studying several cellular phenomena such as neurodegeneration caused by abnormal protein fibrils or manipulating organelles within cells. This could contribute to understand the mechanisms of some diseases or biophenomena, as the axonal growth in neurons. To the best of our knowledge, no other review article has so far provided such a broad view. Despite of the limitations, fiber tips have key roles in Biology/Medicine. Copyright © 2018 Elsevier B.V. All rights reserved.

Size effects in non-linear heat conduction with flux-limited behaviors

NASA Astrophysics Data System (ADS)

Li, Shu-Nan; Cao, Bing-Yang

2017-11-01

Size effects are discussed for several non-linear heat conduction models with flux-limited behaviors, including the phonon hydrodynamic, Lagrange multiplier, hierarchy moment, nonlinear phonon hydrodynamic, tempered diffusion, thermon gas and generalized nonlinear models. For the phonon hydrodynamic, Lagrange multiplier and tempered diffusion models, heat flux will not exist in problems with sufficiently small scale. The existence of heat flux needs the sizes of heat conduction larger than their corresponding critical sizes, which are determined by the physical properties and boundary temperatures. The critical sizes can be regarded as the theoretical limits of the applicable ranges for these non-linear heat conduction models with flux-limited behaviors. For sufficiently small scale heat conduction, the phonon hydrodynamic and Lagrange multiplier models can also predict the theoretical possibility of violating the second law and multiplicity. Comparisons are also made between these non-Fourier models and non-linear Fourier heat conduction in the type of fast diffusion, which can also predict flux-limited behaviors.

Sum-of-squares of polynomials approach to nonlinear stability of fluid flows: an example of application

PubMed Central

Tutty, O.

2015-01-01

With the goal of providing the first example of application of a recently proposed method, thus demonstrating its ability to give results in principle, global stability of a version of the rotating Couette flow is examined. The flow depends on the Reynolds number and a parameter characterizing the magnitude of the Coriolis force. By converting the original Navier–Stokes equations to a finite-dimensional uncertain dynamical system using a partial Galerkin expansion, high-degree polynomial Lyapunov functionals were found by sum-of-squares of polynomials optimization. It is demonstrated that the proposed method allows obtaining the exact global stability limit for this flow in a range of values of the parameter characterizing the Coriolis force. Outside this range a lower bound for the global stability limit was obtained, which is still better than the energy stability limit. In the course of the study, several results meaningful in the context of the method used were also obtained. Overall, the results obtained demonstrate the applicability of the recently proposed approach to global stability of the fluid flows. To the best of our knowledge, it is the first case in which global stability of a fluid flow has been proved by a generic method for the value of a Reynolds number greater than that which could be achieved with the energy stability approach. PMID:26730219

Gene Therapy Delivery Systems for Enhancing Viral and Nonviral Vectors for Cardiac Diseases: Current Concepts and Future Applications

PubMed Central

Katz, Michael G.; Fargnoli, Anthony S.; Williams, Richard D.

2013-01-01

Abstract Gene therapy is one of the most promising fields for developing new treatments for the advanced stages of ischemic and monogenetic, particularly autosomal or X-linked recessive, cardiomyopathies. The remarkable ongoing efforts in advancing various targets have largely been inspired by the results that have been achieved in several notable gene therapy trials, such as the hemophilia B and Leber's congenital amaurosis. Rate-limiting problems preventing successful clinical application in the cardiac disease area, however, are primarily attributable to inefficient gene transfer, host responses, and the lack of sustainable therapeutic transgene expression. It is arguable that these problems are directly correlated with the choice of vector, dose level, and associated cardiac delivery approach as a whole treatment system. Essentially, a delicate balance exists in maximizing gene transfer required for efficacy while remaining within safety limits. Therefore, the development of safe, effective, and clinically applicable gene delivery techniques for selected nonviral and viral vectors will certainly be invaluable in obtaining future regulatory approvals. The choice of gene transfer vector, dose level, and the delivery system are likely to be critical determinants of therapeutic efficacy. It is here that the interactions between vector uptake and trafficking, delivery route means, and the host's physical limits must be considered synergistically for a successful treatment course. PMID:24164239

Technical Digest of the 1998 Summer Topical Meeting on Organic Optics and Optoelectronics

DTIC Science & Technology

1998-07-01

substantially larger voltages (~2x), however, signal distortion and inter- symbol interference due to multiple RF reflections limit their...technology as data page composers. Texas Instrument’s DMD 0-7803-4953-9/98$10.00©1998 IEEE system has already been used in this capacity in several... lithography for fabricating and integrating the heads and sliders. The application of MEMS components and micromachined optical bench packaging techniques

Estimating Logistics Support of Reusable Launch Vehicles During Conceptual Design

NASA Technical Reports Server (NTRS)

Morris, W. D.; White, N. H.; Davies, W. T.; Ebeling, C. E.

1997-01-01

Methods exist to define the logistics support requirements for new aircraft concepts but are not directly applicable to new launch vehicle concepts. In order to define the support requirements and to discriminate among new technologies and processing choices for these systems, NASA Langley Research Center (LaRC) is developing new analysis methods. This paper describes several methods under development, gives their current status, and discusses the benefits and limitations associated with their use.

Studies on the Immunochemical Techniques for Detection of Selected Fungal and Dinoflagellate Toxins.

DTIC Science & Technology

1985-08-15

to be one of the most potent protein inhibitors. It has been found to be associated with several natural outbreaks of mycotoxicoses in both animals...trichothecene mycotoxins and dinoflagellate phytotoxins and subsequently to develop a radioimmunoassay (RIA) or an enzyme-linked immunosorbent assay...of 7% and variation coeffecient of 8%. The minumal detection for DON was around 20 ppb. The application of this method to limited naturally

Surface Abrasive Torsion for Improved Mechanical Properties and Microstructure

NASA Astrophysics Data System (ADS)

Moon, Ji Hyun; Baek, Seung Mi; Lee, Seok Gyu; Yoon, Jae Ik; Lee, Sunghak; Kim, Hyoung Seop

2018-05-01

A novel process of discrete surface abrasion during simple torsion (ST), named "surface abrasive torsion (SAT)," is proposed to overcome the limitation of ST, i.e., insufficient strain for severe plastic deformation (SPD) due to cracks initiated on the surface, by removing the roughened surface region. The effect of SAT on delayed crack initiation was explained using finite element simulations. Larger shear deformation applicable to the specimen in SAT than ST was demonstrated experimentally.

US Army Biomedical Laboratory Annual Progress Report, 1 October 1986-30 September 1987. Volume 1

DTIC Science & Technology

1987-12-07

support of casualties during evacuation within the theater of operations . To fulfill this requirement USABRDL has initiated a project to identify and...Tests of its operational capabilities will be conducted. Aerial application of granular pesticide was done to control ticks at Fort A.P. Hill, Virginia...with limited amounts of hypochlorous acid ; and the testing of several polymeric and monomeric diacetylene compounds as potential indicators to be used

Tunable Thermal Radiative Properties of Nanotube and Nanowire Arrays

DTIC Science & Technology

2011-06-28

1t does not display a currently valid OMB control number PLEASE DO NOT RETURN YOUR FORM TO THE ABOVE ORGANIZATION. 1. REPORT DATE (DD-MM-YYYY) 12...band. Several dielectric function models have been developed to account for different mechanisms, such as Drude’s model for free electrons and...Lorentz oscillator model for phonons [7]. However, the parameters in these models are typically obtained from experiments, limiting their applications in

Technology Transfer Challenges for High-Assurance Software Engineering Tools

NASA Technical Reports Server (NTRS)

Koga, Dennis (Technical Monitor); Penix, John; Markosian, Lawrence Z.

2003-01-01

In this paper, we describe our experience with the challenges thar we are currently facing in our effort to develop advanced software verification and validation tools. We categorize these challenges into several areas: cost benefits modeling, tool usability, customer application domain, and organizational issues. We provide examples of challenges in each area and identrfj, open research issues in areas which limit our ability to transfer high-assurance software engineering tools into practice.

Resonant CARS Detection of OH Radicals.

DTIC Science & Technology

1985-01-31

EXPERIMENTAL Several important factors were considered in the design of a resonant CARS experiment which must detect a molecular free radical in the gas phase...two input frequencie±s of CARS methods is that its application corresponds to a Raman-active molecular is generally limited to those species vibration...tuned device which maintains to detect a molecular free radical in the constant output power of the second har- gas phase. The problems are compounded

MeshVoro: A Three-Dimensional Voronoi Mesh Building Tool for the TOUGH Family of Codes

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

Freeman, C. M.; Boyle, K. L.; Reagan, M.

2013-09-30

Few tools exist for creating and visualizing complex three-dimensional simulation meshes, and these have limitations that restrict their application to particular geometries and circumstances. Mesh generation needs to trend toward ever more general applications. To that end, we have developed MeshVoro, a tool that is based on the Voro (Rycroft 2009) library and is capable of generating complex threedimensional Voronoi tessellation-based (unstructured) meshes for the solution of problems of flow and transport in subsurface geologic media that are addressed by the TOUGH (Pruess et al. 1999) family of codes. MeshVoro, which includes built-in data visualization routines, is a particularly usefulmore » tool because it extends the applicability of the TOUGH family of codes by enabling the scientifically robust and relatively easy discretization of systems with challenging 3D geometries. We describe several applications of MeshVoro. We illustrate the ability of the tool to straightforwardly transform a complex geological grid into a simulation mesh that conforms to the specifications of the TOUGH family of codes. We demonstrate how MeshVoro can describe complex system geometries with a relatively small number of grid blocks, and we construct meshes for geometries that would have been practically intractable with a standard Cartesian grid approach. We also discuss the limitations and appropriate applications of this new technology.« less

Studies of Heavy-Ion Reactions and Transuranic Nuclei

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

Schroeder, W. Udo

2016-07-28

Studies of heavy-ion reactions and transuranic nuclei performed by the University of Rochester Nuclear Science Research Group have been successful in furthering experimental systematics and theoretical understanding of the behavior of nuclear systems excited to their limits of stability. The theoretical results explain specifically the “boiling” and “vaporization” of atomic nuclei, but are more generally applicable to isolated, quantal many-particle systems which, under thermal or mechanical stresses, all disintegrate by evaporation, via surface cluster emission, or via fission-like processes. Accompanying experimental investigations by the group have demonstrated several new types of dynamical instability of nuclei: In central, “head-on” collisions, targetmore » nuclei exhibit limited ability to stop energetic projectile nuclei and to dissipate the imparted linear momentum. Substantial matter overlap (“neck”) between projectile and target nuclei, which is observed at elevated collision energies, can be stretched considerably and break at several places simultaneously. These results provide new testing grounds for microscopic theory of the cohesion of nuclear matter. This property has remained elusive, even though the elementary nucleon-nucleon forces are well known since some time. Technical R&D has resulted in a detailed characterization of a novel plastic material, which can now be used in the design of sensitive diagnostic systems for various types of radio-activity. Innovative application of powerful laser systems has produced intense, controllable sources of exotic particle radioactivity for nuclear investigations. Several students have received their Ph.D. degree in experimental nuclear science for their work on basic nuclear research or R&D projects.« less

Probiotic formulations and applications, the current probiotics market, and changes in the marketplace: a European perspective.

PubMed

Saxelin, Maija

2008-02-01

Europe is a multicultural continent where the consumption of fermented milks has traditionally been high in several countries. Thus, it is no wonder that the market for fermented dairy products with probiotic bacteria has been successful. The market for food applications of probiotics is clearly larger than that for probiotics sold in capsules, sachets, and other pharmaceutical forms. Yogurt-type drinks are the fastest-growing product category, but the diversity of probiotic food applications is not limited to milk-based products. Probiotic fruit juices, berry soups, and soy- and cereal-based fermented products are also sold. Some probiotic strains that are successful in Europe are marketed globally, but there is also a variety of local probiotic strains that are key players in their limited markets. The health messages of probiotic products have focused mainly on general well-being and support of gastrointestinal microbiota. However, because of newly accepted regulation from the European Union regarding health claims, such claims will be evaluated officially, which may substantially change their content. However, more-specific product claims may also appear on the market. This article describes trends and phenomena in mainly the food sector, which covers the most-successful probiotic applications, but food supplements are also discussed.

Current experiences with internet telepathology and possible evolution in the next generation of Internet services.

PubMed

Della Mea, V; Beltrami, C A

2000-01-01

The last five years experience has definitely demonstrated the possible applications of the Internet for telepathology. They may be listed as follows: (a) teleconsultation via multimedia e-mail; (b) teleconsultation via web-based tools; (c) distant education by means of World Wide Web; (d) virtual microscope management through Web and Java interfaces; (e) real-time consultations through Internet-based videoconferencing. Such applications have led to the recognition of some important limits of the Internet, when dealing with telemedicine: (i) no guarantees on the quality of service (QoS); (ii) inadequate security and privacy; (iii) for some countries, low bandwidth and thus low responsiveness for real-time applications. Currently, there are several innovations in the world of the Internet. Different initiatives have been aimed at an amelioration of the Internet protocols, in order to have quality of service, multimedia support, security and other advanced services, together with greater bandwidth. The forthcoming Internet improvements, although induced by electronic commerce, video on demand, and other commercial needs, are of real interest also for telemedicine, because they solve the limits currently slowing down the use of Internet. When such new services will be available, telepathology applications may switch from research to daily practice in a fast way.

Current Experiences with Internet Telepathology and Possible Evolution in the Next Generation of Internet Services

PubMed Central

Della Mea, V.; Beltrami, C. A.

2000-01-01

The last five years experience has definitely demonstrated the possible applications of the Internet for telepathology. They may be listed as follows: (a) teleconsultation via multimedia e‐mail; (b) teleconsultation via web‐based tools; (c) distant education by means of World Wide Web; (d) virtual microscope management through Web and Java interfaces; (e) real‐time consultations through Internet‐based videoconferencing. Such applications have led to the recognition of some important limits of the Internet, when dealing with telemedicine: (i) no guarantees on the quality of service (QoS); (ii) inadequate security and privacy; (iii) for some countries, low bandwidth and thus low responsiveness for real‐time applications. Currently, there are several innovations in the world of the Internet. Different initiatives have been aimed at an amelioration of the Internet protocols, in order to have quality of service, multimedia support, security and other advanced services, together with greater bandwidth. The forthcoming Internet improvements, although induced by electronic commerce, video on demand, and other commercial needs, are of real interest also for telemedicine, because they solve the limits currently slowing down the use of Internet. When such new services will be available, telepathology applications may switch from research to daily practice in a fast way. PMID:11339559

Application of GIS technology in public health: successes and challenges.

PubMed

Fletcher-Lartey, Stephanie M; Caprarelli, Graziella

2016-04-01

The uptake and acceptance of Geographic Information Systems (GIS) technology has increased since the early 1990s and public health applications are rapidly expanding. In this paper, we summarize the common uses of GIS technology in the public health sector, emphasizing applications related to mapping and understanding of parasitic diseases. We also present some of the success stories, and discuss the challenges that still prevent a full scope application of GIS technology in the public health context. Geographical analysis has allowed researchers to interlink health, population and environmental data, thus enabling them to evaluate and quantify relationships between health-related variables and environmental risk factors at different geographical scales. The ability to access, share and utilize satellite and remote-sensing data has made possible even wider understanding of disease processes and of their links to the environment, an important consideration in the study of parasitic diseases. For example, disease prevention and control strategies resulting from investigations conducted in a GIS environment have been applied in many areas, particularly in Africa. However, there remain several challenges to a more widespread use of GIS technology, such as: limited access to GIS infrastructure, inadequate technical and analytical skills, and uneven data availability. Opportunities exist for international collaboration to address these limitations through knowledge sharing and governance.

Analysing causal structures with entropy

PubMed Central

Weilenmann, Mirjam

2017-01-01

A central question for causal inference is to decide whether a set of correlations fits a given causal structure. In general, this decision problem is computationally infeasible and hence several approaches have emerged that look for certificates of compatibility. Here, we review several such approaches based on entropy. We bring together the key aspects of these entropic techniques with unified terminology, filling several gaps and establishing new connections, all illustrated with examples. We consider cases where unobserved causes are classical, quantum and post-quantum, and discuss what entropic analyses tell us about the difference. This difference has applications to quantum cryptography, where it can be crucial to eliminate the possibility of classical causes. We discuss the achievements and limitations of the entropic approach in comparison to other techniques and point out the main open problems. PMID:29225499

Analysing causal structures with entropy

NASA Astrophysics Data System (ADS)

Weilenmann, Mirjam; Colbeck, Roger

2017-11-01

A central question for causal inference is to decide whether a set of correlations fits a given causal structure. In general, this decision problem is computationally infeasible and hence several approaches have emerged that look for certificates of compatibility. Here, we review several such approaches based on entropy. We bring together the key aspects of these entropic techniques with unified terminology, filling several gaps and establishing new connections, all illustrated with examples. We consider cases where unobserved causes are classical, quantum and post-quantum, and discuss what entropic analyses tell us about the difference. This difference has applications to quantum cryptography, where it can be crucial to eliminate the possibility of classical causes. We discuss the achievements and limitations of the entropic approach in comparison to other techniques and point out the main open problems.

Ceramic fibers for matrix composites in high-temperature engine applications

PubMed

Baldus; Jansen; Sporn

1999-07-30

High-temperature engine applications have been limited by the performance of metal alloys and carbide fiber composites at elevated temperatures. Random inorganic networks composed of silicon, boron, nitrogen, and carbon represent a novel class of ceramics with outstanding durability at elevated temperatures. SiBN(3)C was synthesized by pyrolysis of a preceramic N-methylpolyborosilazane made from the single-source precursor Cl(3)Si-NH-BCl(2). The polymer can be processed to a green fiber by melt-spinning, which then undergoes an intermediate curing step and successive pyrolysis. The ceramic fibers, which are presently produced on a semitechnical scale, combine several desired properties relevant for an application in fiber-reinforced ceramic composites: thermal stability, mechanical strength, high-temperature creep resistivity, low density, and stability against oxidation or molten silicon.

Microstructural Analysis of Severe Plastic Deformed Twin Roll Cast AZ31 for the Optimization of Superplastic Properties

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

Young, John P.; Askari, Hesam A.; Heiden, Michael J.

2013-07-08

In recent years magnesium alloys have attracted significant attention as potential candidates to replace many of the heavier metals used in some automotive applications. However, the limited formability of magnesium and its alloys at room temperature has driven interest in the superplastic forming magnesium as an alternative shaping method. Severe plastic deformation techniques have become a well studied method of refining the grain size and modifying the microstructural characteristics of many magnesium alloys to achieve greater superplastic properties. In this study twin roll cast (TRC) AZ31 magnesium alloy was subjected to equal channel angular pressing (ECAP) and friction stir weldingmore » (FSW). The influence of these severe plastic deformation processes on the grain size, texture and grain boundary character distribution was investigated to identify the optimum severe plastic deformation process for the superplastic forming of AZ31.« less

Microfluidic transmission surface plasmon resonance enhancement for biosensor applications

NASA Astrophysics Data System (ADS)

Lertvachirapaiboon, Chutiparn; Baba, Akira; Ekgasit, Sanong; Shinbo, Kazunari; Kato, Keizo; Kaneko, Futao

2017-01-01

The microfluidic transmission surface plasmon resonance (MTSPR) constructed by assembling a gold-coated grating substrate with a microchannel was employed for biosensor application. The transmission surface plasmon resonance spectrum obtained from the MTSPR sensor chip showed a strong and narrow surface plasmon resonance (SPR) peak located between 650 and 800 nm. The maximum SPR excitation was observed at an incident angle of 35°. The MTSPR sensor chip was employed for glucose sensor application. Gold-coated grating substrates were functionalized using 3-mercapto-1-propanesulfonic acid sodium salt and subsequently functionalized using a five-bilayer poly(allylamine hydrochloride)/poly(sodium 4-styrenesulfonate) to facilitate the coupling/decoupling of the surface plasmon and to prepare a uniform surface for sensing. The detection limit of our developed system for glucose was 2.31 mM. This practical platform represents a high possibility of further developing several biomolecules, multiplex systems, and a point-of-care assay for practical biosensor applications.

[Near infrared spectroscopy based process trajectory technology and its application in monitoring and controlling of traditional Chinese medicine manufacturing process].

PubMed

Li, Wen-Long; Qu, Hai-Bin

2016-10-01

In this paper, the principle of NIRS (near infrared spectroscopy)-based process trajectory technology was introduced.The main steps of the technique include:① in-line collection of the processes spectra of different technics; ② unfolding of the 3-D process spectra;③ determination of the process trajectories and their normal limits;④ monitoring of the new batches with the established MSPC (multivariate statistical process control) models.Applications of the technology in the chemical and biological medicines were reviewed briefly. By a comprehensive introduction of our feasibility research on the monitoring of traditional Chinese medicine technical process using NIRS-based multivariate process trajectories, several important problems of the practical applications which need urgent solutions are proposed, and also the application prospect of the NIRS-based process trajectory technology is fully discussed and put forward in the end. Copyright© by the Chinese Pharmaceutical Association.

Applications of maximally concentrating optics for solar energy collection

NASA Astrophysics Data System (ADS)

O'Gallagher, J.; Winston, R.

1985-11-01

A new family of optical concentrators based on a general nonimaging design principle for maximizing the geometric concentration, C, for radiation within a given acceptance half angle ±θα has been developed. The maximum limit exceeds by factors of 2 to 10 that attainable by systems using focusing optics. The wide acceptance angles permitted using these techniques have several unique advantages for solar concentrators including the elimination of the diurnal tracking requirement at intermediate concentrations (up to ˜10x), collection of circumsolar and some diffuse radiation, and relaxed tolerances. Because of these advantages, these types of concentrators have applications in solar energy wherever concentration is desired, e.g. for a wide variety of both thermal and photovoltaic uses. The basic principles of nonimaging optical design are reviewed. Selected configurations for thermal collector applications are discussed and the use of nonimaging elements as secondary concentrators is illustrated in the context of higher concentration applications.

shinyGISPA: A web application for characterizing phenotype by gene sets using multiple omics data combinations.

PubMed

Dwivedi, Bhakti; Kowalski, Jeanne

2018-01-01

While many methods exist for integrating multi-omics data or defining gene sets, there is no one single tool that defines gene sets based on merging of multiple omics data sets. We present shinyGISPA, an open-source application with a user-friendly web-based interface to define genes according to their similarity in several molecular changes that are driving a disease phenotype. This tool was developed to help facilitate the usability of a previously published method, Gene Integrated Set Profile Analysis (GISPA), among researchers with limited computer-programming skills. The GISPA method allows the identification of multiple gene sets that may play a role in the characterization, clinical application, or functional relevance of a disease phenotype. The tool provides an automated workflow that is highly scalable and adaptable to applications that go beyond genomic data merging analysis. It is available at http://shinygispa.winship.emory.edu/shinyGISPA/.

shinyGISPA: A web application for characterizing phenotype by gene sets using multiple omics data combinations

PubMed Central

Dwivedi, Bhakti

2018-01-01

While many methods exist for integrating multi-omics data or defining gene sets, there is no one single tool that defines gene sets based on merging of multiple omics data sets. We present shinyGISPA, an open-source application with a user-friendly web-based interface to define genes according to their similarity in several molecular changes that are driving a disease phenotype. This tool was developed to help facilitate the usability of a previously published method, Gene Integrated Set Profile Analysis (GISPA), among researchers with limited computer-programming skills. The GISPA method allows the identification of multiple gene sets that may play a role in the characterization, clinical application, or functional relevance of a disease phenotype. The tool provides an automated workflow that is highly scalable and adaptable to applications that go beyond genomic data merging analysis. It is available at http://shinygispa.winship.emory.edu/shinyGISPA/. PMID:29415010

Diatomite-Templated Synthesis of Freestanding 3D Graphdiyne for Energy Storage and Catalysis Application.

PubMed

Li, Jiaqiang; Xu, Jing; Xie, Ziqian; Gao, Xin; Zhou, Jingyuan; Xiong, Yan; Chen, Changguo; Zhang, Jin; Liu, Zhongfan

2018-05-01

Graphdiyne (GDY), a new kind of two-dimensional (2D) carbon allotropes, has extraordinary electrical, mechanical, and optical properties, leading to advanced applications in the fields of energy storage, photocatalysis, electrochemical catalysis, and sensors. However, almost all reported methods require metallic copper as a substrate, which severely limits their large-scale application because of the high cost and low specific surface area (SSA) of copper substrate. Here, freestanding three-dimensional GDY (3DGDY) is successfully prepared using naturally abundant and inexpensive diatomite as template. In addition to the intrinsic properties of GDY, the fabricated 3DGDY exhibits a porous structure and high SSA that enable it to be directly used as a lithium-ion battery anode material and a 3D scaffold to create Rh@3DGDY composites, which would hold great potential applications in energy storage and catalysts, respectively. © 2018 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

TREATING HEMOGLOBINOPATHIES USING GENE CORRECTION APPROACHES: PROMISES AND CHALLENGES

PubMed Central

Cottle, Renee N.; Lee, Ciaran M.; Bao, Gang

2016-01-01

Hemoglobinopathies are genetic disorders caused by aberrant hemoglobin expression or structure changes, resulting in severe mortality and health disparities worldwide. Sickle cell disease (SCD) and β-thalassemia, the most common forms of hemoglobinopathies, are typically treated using transfusions and pharmacological agents. Allogeneic hematopoietic stem cell transplantation is the only curative therapy, but has limited clinical applicability. Although gene therapy approaches have been proposed based on the insertion and forced expression of wild-type or anti-sickling β-globin variants, safety concerns may impede their clinical application. A novel curative approach is nuclease-based gene correction, which involves the application of precision genome editing tools to correct the disease-causing mutation. This review describes the development and potential application of gene therapy and precision genome editing approaches for treating SCD and β-thalassemia. The opportunities and challenges in advancing a curative therapy for hemoglobinopathies are also discussed. PMID:27314256

Metagenomic applications in environmental monitoring and bioremediation.

PubMed

Techtmann, Stephen M; Hazen, Terry C

2016-10-01

With the rapid advances in sequencing technology, the cost of sequencing has dramatically dropped and the scale of sequencing projects has increased accordingly. This has provided the opportunity for the routine use of sequencing techniques in the monitoring of environmental microbes. While metagenomic applications have been routinely applied to better understand the ecology and diversity of microbes, their use in environmental monitoring and bioremediation is increasingly common. In this review we seek to provide an overview of some of the metagenomic techniques used in environmental systems biology, addressing their application and limitation. We will also provide several recent examples of the application of metagenomics to bioremediation. We discuss examples where microbial communities have been used to predict the presence and extent of contamination, examples of how metagenomics can be used to characterize the process of natural attenuation by unculturable microbes, as well as examples detailing the use of metagenomics to understand the impact of biostimulation on microbial communities.

Development of a Repeatable Protocol to Uniformly Coat Internal Complex Geometries of Fine Featured 3D Printed Objects with Ceramic Material, including Determination of Viscosity Limits to Properly Coat Certain Pore Sizes

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

Rogers, A.

HEPA filters are commonly used in air filtration systems ranging in application from simple home systems to the more advanced networks used in research and development. Currently, these filters are most often composed of glass fibers with diameter on the order of one micron with polymer binders. These fibers, as well as the polymers used, are known to be fragile and can degrade or become extremely brittle with heat, severely limiting their use in high temperature applications. Ceramics are one promising alternative and can enhance the filtration capabilities compared to the current technology. Because ceramic materials are more thermally resistantmore » and chemically stable, there is great interest in developing a repeatable protocol to uniformly coat fine featured polymer objects with ceramic material for use as a filter. The purpose of this experiment is to determine viscosity limits that are able to properly coat certain pore sizes in 3D printed objects, and additionally to characterize the coatings themselves. Latex paint was used as a surrogate because it is specifically designed to produce uniform coatings.« less

A Helium GC/IMS for the Analysis of Extraterrestrial Volatiles in Exobiology Flight Experiments

NASA Technical Reports Server (NTRS)

Kojiro, Daniel R.; Carle, Glenn C.; Humphry, Donald E.; Shao, Maxine; Takeuchi, Nori

1995-01-01

For exobiology experiments on board spacecraft or space probes, a wide range of chemical species often must be detected and identified. The limited amount of power and space available for flight instruments severely limits the number of instruments that can be flown on any given mission. It is important then, that these experiments utilize instrumentation with universal response, so that all species of interest can be analyzed. Instrumentation to fulfill the analytical requirements of exobiology experiments has been developed utilizing Gas Chromatography - Ion Mobility Spectrometry. The Gas Chromatograph (GC) combines columns developed specifically for the complex mixtures anticipated with highly sensitive Metastable Ionization Detectors (a type of Helium Ionization Detector). To satisfy the limitations placed on resources, the Ion Mobility Spectrometer (IMS) uses the same ultra high purity helium as the GC. This GC-MS provides the analytical capability to fulfill a wide range of exobiology flight experiment applications and has been included on a proposed Discovery Mission and proposals for both Lander and Orbiter of the European Space Agency's Rosetta Comet Mission. A data base of helium IMS spectra is now being built for these future applications.

Stress intensity factors and COD in an orthotropic strip

NASA Technical Reports Server (NTRS)

Kaya, A. C.; Erdogan, F.

1980-01-01

The elasticity problem for an orthotropic strip or a beam with an internal or an edge crack under general loading conditions is considered. The numerical results are given for four basic loading conditions, namely, uniform tension, pure bending, three point bending, and concentrated surface shear loading. For the strip with an edge crack additional results regarding the crack opening displacements are obtained by using the plastic strip model. A critical quantity which is tabulated is the maximum compressive stress in the plane of the crack. It is shown that this stress may easily exceed the yield limit in compression and hence may severely limit the range of application of the plasticity results.

Application of global positioning system to determination of tectonic plate movements and crustal deformations

NASA Technical Reports Server (NTRS)

Anderle, R. J.

1978-01-01

It is shown that pseudo-range measurements to four GPS satellites based on correlation of the pseudo random code transmissions from the satellites can be used to determine the relative position of ground stations which are separated by several hundred kilometers to a precision at the centimeter level. Carrier signal measurements during the course of passage of satellites over a pair of stations also yield centimeter precision in the relative position, but oscillator instabilities limit the accuracy. The accuracy of solutions based on either type of data is limited by unmodeled tropospheric refraction effects which would reach 5 centimeters at low elevation angles for widely separated stations.

Practical gigahertz quantum key distribution robust against channel disturbance.

PubMed

Wang, Shuang; Chen, Wei; Yin, Zhen-Qiang; He, De-Yong; Hui, Cong; Hao, Peng-Lei; Fan-Yuan, Guan-Jie; Wang, Chao; Zhang, Li-Jun; Kuang, Jie; Liu, Shu-Feng; Zhou, Zheng; Wang, Yong-Gang; Guo, Guang-Can; Han, Zheng-Fu

2018-05-01

Quantum key distribution (QKD) provides an attractive solution for secure communication. However, channel disturbance severely limits its application when a QKD system is transferred from the laboratory to the field. Here a high-speed Faraday-Sagnac-Michelson QKD system is proposed that can automatically compensate for the channel polarization disturbance, which largely avoids the intermittency limitations of environment mutation. Over a 50 km fiber channel with 30 Hz polarization scrambling, the practicality of this phase-coding QKD system was characterized with an interference fringe visibility of 99.35% over 24 h and a stable secure key rate of 306 k bits/s over seven days without active polarization alignment.

Uniformity of LED light illumination in application to direct imaging lithography

NASA Astrophysics Data System (ADS)

Huang, Ting-Ming; Chang, Shenq-Tsong; Tsay, Ho-Lin; Hsu, Ming-Ying; Chen, Fong-Zhi

2016-09-01

Direct imaging has widely applied in lithography for a long time because of its simplicity and easy-maintenance. Although this method has limitation of lithography resolution, it is still adopted in industries. Uniformity of UV irradiance for a designed area is an important requirement. While mercury lamps were used as the light source in the early stage, LEDs have drawn a lot of attention for consideration from several aspects. Although LED has better and better performance, arrays of LEDs are required to obtain desired irradiance because of limitation of brightness for a single LED. Several effects are considered that affect the uniformity of UV irradiance such as alignment of optics, temperature of each LED, performance of each LED due to production uniformity, and pointing of LED module. Effects of these factors are considered to study the uniformity of LED Light Illumination. Numerical analysis is performed by assuming a serious of control factors to have a better understanding of each factor.

Liquid droplet radiator performance studies

NASA Astrophysics Data System (ADS)

Mattick, A. T.; Hertzberg, A.

By making use of droplets rather than solid surfaces to radiate waste heat in space, the liquid droplet radiator (LDR) achieves a radiating area/mass much larger than that of conventional radiators which use fins or heat pipes. The lightweight potential of the LDR is shown to be limited primarily by the radiative properties of the droplets. The requirement that the LDR heat transfer fluid have a very low vapor pressure limits the choice of fluids to relatively few—several liquid metals and Dow 705 silicone fluid are the only suitable candidates so far identified. An experimental determination of the emittance of submillimeter droplets of Dow 705 fluid indicates than an LDR using this fluid at temperatures of 275-335 K would be ⋍ 10 times lighter than the lightest solid surface radiators. Although several liquid metals appear to offer excellent performance in LDR applications at temperatures between 200 K and 975 K, experimental determination of liquid metal emissivities is needed for a conclusive assessment.

Liquid droplet radiator performance studies

NASA Technical Reports Server (NTRS)

Mattick, A. T.; Hertzberg, A.

1984-01-01

By making use of droplets rather than solid surfaces to radiate waste heat in space, the liquid-droplet radiator (LDR) achieves a radiating area/mass much larger than that of conventional radiators which use fins or heat pipes. The light-weight potential of the LDR is shown to be limited primarily by the radiative properties of the droplets. The requirement that the LDR heat-transfer fluid have a very low vapor pressure limits the choice of fluids to relatively few several liquid metals and a silicone fluid are the only suitable candidates so far identified. An experimental determination of the emittance of submillimeter droplets of the silicon fluid indicates that an LDR using this fluid at temperatures of 275-335 K would be about 10 times lighter than the lightest solid-surface radiators. Although several liquid metals appear to offer excellent performance in LDR applications at temperatures between 200 and 975 K, experimental determination of liquid-metal emissivities is needed for a conclusive assessment.

Liquid droplet radiator performance studies

NASA Astrophysics Data System (ADS)

Mattick, A. T.; Hertzberg, A.

1984-10-01

By making use of droplets rather than solid surfaces to radiate waste heat in space, the liquid-droplet radiator (LDR) achieves a radiating area/mass much larger than that of conventional radiators which use fins or heat pipes. The light-weight potential of the LDR is shown to be limited primarily by the radiative properties of the droplets. The requirement that the LDR heat-transfer fluid have a very low vapor pressure limits the choice of fluids to relatively few several liquid metals and a silicone fluid are the only suitable candidates so far identified. An experimental determination of the emittance of submillimeter droplets of the silicon fluid indicates that an LDR using this fluid at temperatures of 275-335 K would be about 10 times lighter than the lightest solid-surface radiators. Although several liquid metals appear to offer excellent performance in LDR applications at temperatures between 200 and 975 K, experimental determination of liquid-metal emissivities is needed for a conclusive assessment.

Advances in ultrasensitive mass spectrometry of organic molecules.

PubMed

Kandiah, Mathivathani; Urban, Pawel L

2013-06-21

Ultrasensitive mass spectrometric analysis of organic molecules is important for various branches of chemistry, and other fields including physics, earth and environmental sciences, archaeology, biomedicine, and materials science. It finds applications--as an enabling tool--in systems biology, biological imaging, clinical analysis, and forensics. Although there are a number of technical obstacles associated with the analysis of samples by mass spectrometry at ultratrace level (for example analyte losses during sample preparation, insufficient sensitivity, ion suppression), several noteworthy developments have been made over the years. They include: sensitive ion sources, loss-free interfaces, ion optics components, efficient mass analyzers and detectors, as well as "smart" sample preparation strategies. Some of the mass spectrometric methods published to date can achieve sensitivity which is by several orders of magnitude higher than that of alternative approaches. Femto- and attomole level limits of detection are nowadays common, while zepto- and yoctomole level limits of detection have also been reported. We envision that the ultrasensitive mass spectrometric assays will soon contribute to new discoveries in bioscience and other areas.

NASA Applications and Lessons Learned in Reliability Engineering

NASA Technical Reports Server (NTRS)

Safie, Fayssal M.; Fuller, Raymond P.

2011-01-01

Since the Shuttle Challenger accident in 1986, communities across NASA have been developing and extensively using quantitative reliability and risk assessment methods in their decision making process. This paper discusses several reliability engineering applications that NASA has used over the year to support the design, development, and operation of critical space flight hardware. Specifically, the paper discusses several reliability engineering applications used by NASA in areas such as risk management, inspection policies, components upgrades, reliability growth, integrated failure analysis, and physics based probabilistic engineering analysis. In each of these areas, the paper provides a brief discussion of a case study to demonstrate the value added and the criticality of reliability engineering in supporting NASA project and program decisions to fly safely. Examples of these case studies discussed are reliability based life limit extension of Shuttle Space Main Engine (SSME) hardware, Reliability based inspection policies for Auxiliary Power Unit (APU) turbine disc, probabilistic structural engineering analysis for reliability prediction of the SSME alternate turbo-pump development, impact of ET foam reliability on the Space Shuttle System risk, and reliability based Space Shuttle upgrade for safety. Special attention is given in this paper to the physics based probabilistic engineering analysis applications and their critical role in evaluating the reliability of NASA development hardware including their potential use in a research and technology development environment.

The impact of Sun-weather research on forecasting

NASA Technical Reports Server (NTRS)

Larsen, M. F.

1979-01-01

The possible impact of Sun-weather research on forecasting is examined. The type of knowledge of the effect is evaluated to determine if it is in a form that can be used for forecasting purposes. It is concluded that the present understanding of the effect does not lend itself readily to applications for forecast purposes. The limits of present predictive skill are examined and it is found that skill is most lacking for prediction of the smallest scales of atmospheric motion. However, it is not expected that Sun-weather research will have any significant impact on forecasting the smaller scales since predictability at these scales is limited by the finite grid size resolution and the time scales of turbulent diffusion. The predictability limits for the largest scales are on the order of several weeks although presently only a one week forecast is achievable.

A versatile genetic tool for post-translational control of gene expression in Drosophila melanogaster

PubMed Central

Sethi, Sachin

2017-01-01

Several techniques have been developed to manipulate gene expression temporally in intact neural circuits. However, the applicability of current tools developed for in vivo studies in Drosophila is limited by their incompatibility with existing GAL4 lines and side effects on physiology and behavior. To circumvent these limitations, we adopted a strategy to reversibly regulate protein degradation with a small molecule by using a destabilizing domain (DD). We show that this system is effective across different tissues and developmental stages. We further show that this system can be used to control in vivo gene expression levels with low background, large dynamic range, and in a reversible manner without detectable side effects on the lifespan or behavior of the animal. Additionally, we engineered tools for chemically controlling gene expression (GAL80-DD) and recombination (FLP-DD). We demonstrate the applicability of this technology in manipulating neuronal activity and for high-efficiency sparse labeling of neuronal populations. PMID:29140243

Flexible organic transistors and circuits with extreme bending stability

NASA Astrophysics Data System (ADS)

Sekitani, Tsuyoshi; Zschieschang, Ute; Klauk, Hagen; Someya, Takao

2010-12-01

Flexible electronic circuits are an essential prerequisite for the development of rollable displays, conformable sensors, biodegradable electronics and other applications with unconventional form factors. The smallest radius into which a circuit can be bent is typically several millimetres, limited by strain-induced damage to the active circuit elements. Bending-induced damage can be avoided by placing the circuit elements on rigid islands connected by stretchable wires, but the presence of rigid areas within the substrate plane limits the bending radius. Here we demonstrate organic transistors and complementary circuits that continue to operate without degradation while being folded into a radius of 100μm. This enormous flexibility and bending stability is enabled by a very thin plastic substrate (12.5μm), an atomically smooth planarization coating and a hybrid encapsulation stack that places the transistors in the neutral strain position. We demonstrate a potential application as a catheter with a sheet of transistors and sensors wrapped around it that enables the spatially resolved measurement of physical or chemical properties inside long, narrow tubes.

Sandia National Laboratories proof-of-concept robotic security vehicle

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

Harrington, J.J.; Jones, D.P.; Klarer, P.R.

1989-01-01

Several years ago Sandia National Laboratories developed a prototype interior robot that could navigate autonomously inside a large complex building to air and test interior intrusion detection systems. Recently the Department of Energy Office of Safeguards and Security has supported the development of a vehicle that will perform limited security functions autonomously in a structured exterior environment. The goal of the first phase of this project was to demonstrate the feasibility of an exterior robotic vehicle for security applications by using converted interior robot technology, if applicable. An existing teleoperational test bed vehicle with remote driving controls was modified andmore » integrated with a newly developed command driving station and navigation system hardware and software to form the Robotic Security Vehicle (RSV) system. The RSV, also called the Sandia Mobile Autonomous Navigator (SANDMAN), has been successfully used to demonstrate that teleoperated security vehicles which can perform limited autonomous functions are viable and have the potential to decrease security manpower requirements and improve system capabilities. 2 refs., 3 figs.« less

Solar Thermal Utility-Scale Joint Venture Program (USJVP) Final Report

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

MANCINI,THOMAS R.

2001-04-01

Several years ago Sandia National Laboratories developed a prototype interior robot [1] that could navigate autonomously inside a large complex building to aid and test interior intrusion detection systems. Recently the Department of Energy Office of Safeguards and Security has supported the development of a vehicle that will perform limited security functions autonomously in a structured exterior environment. The goal of the first phase of this project was to demonstrate the feasibility of an exterior robotic vehicle for security applications by using converted interior robot technology, if applicable. An existing teleoperational test bed vehicle with remote driving controls was modifiedmore » and integrated with a newly developed command driving station and navigation system hardware and software to form the Robotic Security Vehicle (RSV) system. The RSV, also called the Sandia Mobile Autonomous Navigator (SANDMAN), has been successfully used to demonstrate that teleoperated security vehicles which can perform limited autonomous functions are viable and have the potential to decrease security manpower requirements and improve system capabilities.« less

Mobile Application-Assisted Cognitive Behavioral Therapy for Insomnia in an Older Adult.

PubMed

Chen, Yong-Xiang; Hung, Yi-Ping; Chen, Hsi-Chung

2016-04-01

Current evidence suggests potential efficacy of cognitive behavioral therapy for insomnia (CBT-I) in older adults. Mobile applications (apps) have been developed to facilitate CBT-I in the general population. However, because of deteriorating perceptual and cognitive functioning, the effectiveness of mobile apps in older adults remains unknown. This case report aims to demonstrate the utilization, advantages, and limitations of mobile app-assisted CBT-I in an older female adult. An app ("Win-Win aSleep" [WWaS]) was applied in a six-session CBT-I treatment. The patient successfully discontinued her hypnotics and had restored sleep quality after the intervention with WWaS-assisted CBT-I. Several limitations of WWaS were summarized, and pertinent approaches for enhancing future work were discussed. Mobile apps integrating wearable devices might overcome the difficulty for applying WWaS in older adults. In addition to tailored design of mobile technology for older adults, psychosocial support for the utilization of apps may not only enhance the compliance but also provide additional connection to the environment.

Application of in-situ bioassays with macrophytes in aquatic mesocosm studies.

PubMed

Coors, Anja; Kuckelkorn, Jochen; Hammers-Wirtz, Monika; Strauss, Tido

2006-10-01

Aquatic mesocosm studies assess ecotoxicological effects of chemicals by using small artificial ponds as models of lentic ecosystems. In this study, methods of controlled insertion of macrophytes within an outdoor mesocosm study were explored. Although analytically confirmed concentrations of the model herbicide terbuthylazine were high enough to expect direct effects on phytoplankton, functional parameters and dominant taxa abundance indicated only minor and transient effects. In-situ assays with Lemna minor, Myriophyllum spicatum, Potamogeton lucens and Chara globularis revealed adverse effects at concentrations in accordance with literature data. Complex interactions such as nutrient limitation and competition were possible reasons for the observed growth promotion at the lower concentration of about 5 microg/l terbuthylazine. The approach of macrophyte in-situ bioassays within a mesocosm study proved to be applicable. Presumed advantages are simultaneous acquisition of toxicity data for several species of aquatic plants under more realistic conditions compared to laboratory tests and inclusion of macrophytes as important structural and functional components in mesocosms while limiting their domination of the model ecosystem.

Two-lattice models of trace element behavior: A response

NASA Astrophysics Data System (ADS)

Ellison, Adam J. G.; Hess, Paul C.

1990-08-01

Two-lattice melt components of Bottinga and Weill (1972), Nielsen and Drake (1979), and Nielsen (1985) are applied to major and trace element partitioning between coexisting immiscible liquids studied by RYERSON and Hess (1978) and Watson (1976). The results show that (1) the set of components most successful in one system is not necessarily portable to another system; (2) solution non-ideality within a sublattice severely limits applicability of two-lattice models; (3) rigorous application of two-lattice melt components may yield effective partition coefficients for major element components with no physical interpretation; and (4) the distinction between network-forming and network-modifying components in the sense of the two-lattice models is not clear cut. The algebraic description of two-lattice models is such that they will most successfully limit the compositional dependence of major and trace element solution behavior when the effective partition coefficient of the component of interest is essentially the same as the bulk partition coefficient of all other components within its sublattice.

A generic model of contagious disease and its application to human-to-human transmission of avian influenza.

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

Hirsch, Gary B.

2007-03-01

Modeling contagious diseases has taken on greater importance over the past several years as diseases such as SARS and avian influenza have raised concern about worldwide pandemics. Most models developed to consider projected outbreaks have been specific to a single disease. This paper describes a generic System Dynamics contagious disease model and its application to human-to-human transmission of a mutant version of avian influenza. The model offers the option of calculating rates of new infections over time based either on a fixed ''reproductive number'' that is traditional in contagious disease models or on contact rates for different sub-populations and likelihoodmore » of transmission per contact. The paper reports on results with various types of interventions. These results suggest the potential importance of contact tracing, limited quarantine, and targeted vaccination strategies as methods for controlling outbreaks, especially when vaccine supplies may initially be limited and the efficacy of anti-viral drugs uncertain.« less

On the limited recognition of inorganic surfaces by short peptides compared with antibodies.

PubMed

Artzy-Schnirman, Arbel; Abu-Shah, Enas; Dishon, Matan; Soifer, Hadas; Sivan, Yotam; Reiter, Yoram; Benhar, Itai; Sivan, Uri

2014-06-01

The vast potential applications of biomolecules that bind inorganic surfaces led mostly to the isolation of short peptides that target selectively specific materials. The demonstrated differential affinity toward certain surfaces created the impression that the recognition capacity of short peptides may match that of rigid biomolecules. In the following, we challenge this view by comparing the capacity of antibody molecules to discriminate between the (100) and (111A) facets of a gallium arsenide semiconductor crystal with the capacity of short peptides to do the same. Applying selection from several peptide and single chain phage display libraries, we find a number of antibody molecules that bind preferentially a given crystal facet but fail to isolate, in dozens of attempts, a single peptide capable of such recognition. The experiments underscore the importance of rigidity to the recognition of inorganic flat targets and therefore set limitations on potential applications of short peptides in biomimetics. Copyright © 2014 European Peptide Society and John Wiley & Sons, Ltd.

Recent advances on the understanding of structural and composition evolution of LMR cathodes for Li-ion batteries

DOE PAGES

Yan, Pengfei; Zheng, Jianming; Xiao, Jie; ...

2015-06-08

Lithium-rich, magnesium-rich (LMR) cathode materials have been regarded as one of the very promising cathodes for Li-ion battery applications. However, their practical application is still limited by several challenges, especially by their limited electrochemical stability rate capability. In this work, we present recent progresses on the understanding of the structural and composition evolution of LMR cathode materials with emphasis being placed on the correlation between structural/chemical evolution and electrochemical properties. In particular, using Li [Li 0.2Ni 0.2Mn 0.6O 2 as a typical example, we clearly illustrate the structural characteristics of the pristine materials and their dependence on the materials processingmore » history, cycling induced structural degradation/chemical partition and their correlation with degradation of electrochemical performance. The fundamental understanding obtained in this work may also guide the design and preparation of new cathode materials based on ternary system of transitional metal oxide.« less

Fracture mechanics life analytical methods verification testing

NASA Technical Reports Server (NTRS)

Favenesi, J. A.; Clemons, T. G.; Riddell, W. T.; Ingraffea, A. R.; Wawrzynek, P. A.

1994-01-01

The objective was to evaluate NASCRAC (trademark) version 2.0, a second generation fracture analysis code, for verification and validity. NASCRAC was evaluated using a combination of comparisons to the literature, closed-form solutions, numerical analyses, and tests. Several limitations and minor errors were detected. Additionally, a number of major flaws were discovered. These major flaws were generally due to application of a specific method or theory, not due to programming logic. Results are presented for the following program capabilities: K versus a, J versus a, crack opening area, life calculation due to fatigue crack growth, tolerable crack size, proof test logic, tearing instability, creep crack growth, crack transitioning, crack retardation due to overloads, and elastic-plastic stress redistribution. It is concluded that the code is an acceptable fracture tool for K solutions of simplified geometries, for a limited number of J and crack opening area solutions, and for fatigue crack propagation with the Paris equation and constant amplitude loads when the Paris equation is applicable.

40 CFR 432.13 - Effluent limitations attainable by the application of the best available technology economically...

Code of Federal Regulations, 2014 CFR

2014-07-01

... application of the best available technology economically achievable (BAT). 432.13 Section 432.13 Protection... limitations attainable by the application of the best available technology economically achievable (BAT... effluent limitations representing the application of BAT: Effluent Limitations [BAT] Regulatedparameter...

40 CFR 432.13 - Effluent limitations attainable by the application of the best available technology economically...

Code of Federal Regulations, 2012 CFR

2012-07-01

... application of the best available technology economically achievable (BAT). 432.13 Section 432.13 Protection... limitations attainable by the application of the best available technology economically achievable (BAT... effluent limitations representing the application of BAT: Effluent Limitations [BAT] Regulatedparameter...

40 CFR 432.113 - Effluent limitations attainable by the application of the best available technology economically...

Code of Federal Regulations, 2012 CFR

2012-07-01

... application of the best available technology economically achievable (BAT). 432.113 Section 432.113 Protection... limitations attainable by the application of the best available technology economically achievable (BAT... effluent limitations representing the application of BAT: Effluent Limitations [BAT] Regulatedparameter...

40 CFR 432.113 - Effluent limitations attainable by the application of the best available technology economically...

Code of Federal Regulations, 2013 CFR

2013-07-01

... application of the best available technology economically achievable (BAT). 432.113 Section 432.113 Protection... limitations attainable by the application of the best available technology economically achievable (BAT... effluent limitations representing the application of BAT: Effluent Limitations [BAT] Regulatedparameter...

40 CFR 432.13 - Effluent limitations attainable by the application of the best available technology economically...

Code of Federal Regulations, 2013 CFR

2013-07-01

... application of the best available technology economically achievable (BAT). 432.13 Section 432.13 Protection... limitations attainable by the application of the best available technology economically achievable (BAT... effluent limitations representing the application of BAT: Effluent Limitations [BAT] Regulatedparameter...

40 CFR 432.113 - Effluent limitations attainable by the application of the best available technology economically...

Code of Federal Regulations, 2014 CFR

2014-07-01

... application of the best available technology economically achievable (BAT). 432.113 Section 432.113 Protection... limitations attainable by the application of the best available technology economically achievable (BAT... effluent limitations representing the application of BAT: Effluent Limitations [BAT] Regulatedparameter...

Enabling Searches on Wavelengths in a Hyperspectral Indices Database

NASA Astrophysics Data System (ADS)

Piñuela, F.; Cerra, D.; Müller, R.

2017-10-01

Spectral indices derived from hyperspectral reflectance measurements are powerful tools to estimate physical parameters in a non-destructive and precise way for several fields of applications, among others vegetation health analysis, coastal and deep water constituents, geology, and atmosphere composition. In the last years, several micro-hyperspectral sensors have appeared, with both full-frame and push-broom acquisition technologies, while in the near future several hyperspectral spaceborne missions are planned to be launched. This is fostering the use of hyperspectral data in basic and applied research causing a large number of spectral indices to be defined and used in various applications. Ad hoc search engines are therefore needed to retrieve the most appropriate indices for a given application. In traditional systems, query input parameters are limited to alphanumeric strings, while characteristics such as spectral range/ bandwidth are not used in any existing search engine. Such information would be relevant, as it enables an inverse type of search: given the spectral capabilities of a given sensor or a specific spectral band, find all indices which can be derived from it. This paper describes a tool which enables a search as described above, by using the central wavelength or spectral range used by a given index as a search parameter. This offers the ability to manage numeric wavelength ranges in order to select indices which work at best in a given set of wavelengths or wavelength ranges.

Treatment of severe burn with DermACELL(®), an acellular dermal matrix.

PubMed

Chen, Shyi-Gen; Tzeng, Yuan-Sheng; Wang, Chih-Hsin

2012-01-01

For treatment of skin burn injuries, there exist several methods of treatment related to tissue regeneration, including the use of autograft skin and cryopreserved skin. However, each method has drawbacks. An alternative method for tissue regeneration is allograft acellular dermal matrix, with potential as a biocompatible scaffold for new tissue growth. One recently produced material of this type is DermACELL(®), which was used in this case presentation for treating a scar resulting from second- and third-degree burns in a 33-year-old female patient. The patient presented with significant hypertrophic scarring from the elbow to the hand and with limited wrist and elbow motion. The scarring was removed, and the patient was treated with a 1:3 mesh of DermACELL. The wound was resurfaced with a split thickness skin graft, and postoperative care included application of pressure garment and silicone sheet, as well as range of motion exercise and massage. At 30 days after DermACELL application, the wound appeared well-healed with little scar formation. At 180 days post-application, the wound continued to appear healed well without significant scar formation. Additionally, the wound was supple, and the patient experienced significant improvement in range of motion. In the case presented, DermACELL appears to have been a successful method of treatment for scarring due to severe burns by preventing further scar formation and improving range of motion.

Influence of thermally activated processes on the deformation behavior during low temperature ECAP

NASA Astrophysics Data System (ADS)

Fritsch, S.; Scholze, M.; F-X Wagner, M.

2016-03-01

High strength aluminum alloys are generally hard to deform. Therefore, the application of conventional severe plastic deformation methods to generate ultrafine-grained microstructures and to further increase strength is considerably limited. In this study, we consider low temperature deformation in a custom-built, cooled equal channel angular pressing (ECAP) tool (internal angle 90°) as an alternative approach to severely plastically deform a 7075 aluminum alloy. To document the maximum improvement of mechanical properties, these alloys are initially deformed from a solid solution heat-treated condition. We characterize the mechanical behavior and the microstructure of the coarse grained initial material at different low temperatures, and we analyze how a tendency for the PLC effect and the strain-hardening rate affect the formability during subsequent severe plastic deformation at low temperatures. We then discuss how the deformation temperature and velocity influence the occurrence of PLC effects and the homogeneity of the deformed ECAP billets. Besides the mechanical properties and these microstructural changes, we discuss technologically relevant processing parameters (such as pressing forces) and practical limitations, as well as changes in fracture behavior of the low temperature deformed materials as a function of deformation temperature.

Low-Noise Wide Bandwith, Hot Electron Bolometer Mixers for Submillimeter Wavelengths

NASA Technical Reports Server (NTRS)

McGrath, W. R.

1995-01-01

Recently a novel superconductive hot-electron micro-bolometer has been proposed which is both fast and sensitive (D. E. Prober, Appl. Phys. Lett. 62, 2119, 1993). This device has several important properties which make it useful as a heterodyne sensor for radioastronomy applications at frequencies above 1 THz. The thermal response time of the device is fast enough, several 10's of picoseconds, to allow for IF's of several GHz. This bolometer mixer should operate well up to at least 10 THz. There is no energy gap limitation as in an SIS mixer, since the mixing process relies on heating of the electron gas. In fact, rf power is absorbed more uniformly above the gap frequency. The mixer noise should be near quantum-limited, and the local oscillator (LO) power requirement is very low: / 10 nW for a Nb device. One of the unique features of this device is that it employs rapid electron diffusion into a normal metal, rather than phonon emission, as the thermal conductance that cools the heated electrons. In order for diffusion to dominate over phonon emission, the device must be short, less than 0.5.

Practical Issues of Wireless Mobile Devices Usage with Downlink Optimization

NASA Astrophysics Data System (ADS)

Krejcar, Ondrej; Janckulik, Dalibor; Motalova, Leona

Mobile device makers produce tens of new complex mobile devices per year to put users a special mobile device with a possibility to do anything, anywhere, anytime. These devices can operate full scale applications with nearly the same comfort as their desktop equivalents only with several limitations. One of such limitation is insufficient download on wireless connectivity in case of the large multimedia files. Main area of paper is in a possibilities description of solving this problem as well as the test of several new mobile devices along with server interface tests and common software descriptions. New devices have a full scale of wireless connectivity which can be used not only to communication with outer land. Several such possibilities of use are described. Mobile users will have also an online connection to internet all time powered on. Internet is mainly the web pages but the web services use is still accelerate up. The paper deal also with a possibility of maximum user amounts to have a connection at same time to current server type. At last the new kind of database access - Linq technology is compare to ADO.NET in response time meaning.

Nanoscopy for nanoscience: how super-resolution microscopy extends imaging for nanotechnology.

PubMed

Johnson, Sam A

2015-01-01

Imaging methods have presented scientists with powerful means of investigation for centuries. The ability to resolve structures using light microscopes is though limited to around 200 nm. Fluorescence-based super-resolution light microscopy techniques of several principles and methods have emerged in recent years and offer great potential to extend the capabilities of microscopy. This resolution improvement is especially promising for nanoscience where the imaging of nanoscale structures is inherently restricted by the resolution limit of standard forms of light microscopy. Resolution can be improved by several distinct approaches including structured illumination microscopy, stimulated emission depletion, and single-molecule positioning methods such as photoactivated localization microscopy and stochastic optical reconstruction microscopy and several derivative variations of each of these. These methods involve substantial differences in the resolutions achievable in the different axes, speed of acquisition, compatibility with different labels, ease of use, hardware complexity, and compatibility with live biological samples. The field of super-resolution imaging and its application to nanotechnology is relatively new and still rapidly developing. An overview of how these methods may be used with nanomaterials is presented with some examples of pioneering uses of these approaches. © 2014 Wiley Periodicals, Inc.

Nektar++: An open-source spectral/ hp element framework

NASA Astrophysics Data System (ADS)

Cantwell, C. D.; Moxey, D.; Comerford, A.; Bolis, A.; Rocco, G.; Mengaldo, G.; De Grazia, D.; Yakovlev, S.; Lombard, J.-E.; Ekelschot, D.; Jordi, B.; Xu, H.; Mohamied, Y.; Eskilsson, C.; Nelson, B.; Vos, P.; Biotto, C.; Kirby, R. M.; Sherwin, S. J.

2015-07-01

Nektar++ is an open-source software framework designed to support the development of high-performance scalable solvers for partial differential equations using the spectral/ hp element method. High-order methods are gaining prominence in several engineering and biomedical applications due to their improved accuracy over low-order techniques at reduced computational cost for a given number of degrees of freedom. However, their proliferation is often limited by their complexity, which makes these methods challenging to implement and use. Nektar++ is an initiative to overcome this limitation by encapsulating the mathematical complexities of the underlying method within an efficient C++ framework, making the techniques more accessible to the broader scientific and industrial communities. The software supports a variety of discretisation techniques and implementation strategies, supporting methods research as well as application-focused computation, and the multi-layered structure of the framework allows the user to embrace as much or as little of the complexity as they need. The libraries capture the mathematical constructs of spectral/ hp element methods, while the associated collection of pre-written PDE solvers provides out-of-the-box application-level functionality and a template for users who wish to develop solutions for addressing questions in their own scientific domains.

Impact Foam Testing for Multi-Mission Earth Entry Vehicle Applications

NASA Technical Reports Server (NTRS)

Glaab, Louis J.; Agrawal, Paul; Hawbaker, James

2013-01-01

Multi-Mission Earth Entry Vehicles (MMEEVs) are blunt-body vehicles designed with the purpose of transporting payloads from outer space to the surface of the Earth. To achieve high-reliability and minimum weight, MMEEVs avoid use of limited-reliability systems, such as parachutes and retro-rockets, instead using built-in impact attenuators to absorb energy remaining at impact to meet landing loads requirements. The Multi-Mission Systems Analysis for Planetary Entry (M-SAPE) parametric design tool is used to facilitate the design of MMEEVs and develop the trade space. Testing was conducted to characterize the material properties of several candidate impact foam attenuators to enhance M-SAPE analysis. In the current effort, two different Rohacell foams were tested to determine their thermal conductivity in support of MMEEV design applications. These applications include thermal insulation during atmospheric entry, impact attenuation, and post-impact thermal insulation in support of thermal soak analysis. Results indicate that for these closed-cell foams, the effect of impact is limited on thermal conductivity due to the venting of the virgin material gas and subsequent ambient air replacement. Results also indicate that the effect of foam temperature is significant compared to data suggested by manufacturer's specifications.

Design of a novel class of protein-based magnetic resonance imaging contrast agents for the molecular imaging of cancer biomarkers

PubMed Central

Xue, Shenghui; Qiao, Jingjuan; Pu, Fan; Cameron, Mathew; Yang, Jenny J.

2014-01-01

Magnetic resonance imaging (MRI) of disease biomarkers, especially cancer biomarkers, could potentially improve our understanding of the disease and drug activity during preclinical and clinical drug treatment and patient stratification. MRI contrast agents with high relaxivity and targeting capability to tumor biomarkers are highly required. Extensive work has been done to develop MRI contrast agents. However, only a few limited literatures report that protein residues can function as ligands to bind Gd3+ with high binding affinity, selectivity, and relaxivity. In this paper, we focus on reporting our current progress on designing a novel class of protein-based Gd3+ MRI contrast agents (ProCAs) equipped with several desirable capabilities for in vivo application of MRI of tumor biomarkers. We will first discuss our strategy for improving the relaxivity by a novel protein-based design. We then discuss the effect of increased relaxivity of ProCAs on improving the detection limits for MRI contrast agent, especially for in vivo application. We will further report our efforts to improve in vivo imaging capability and our achievement in molecular imaging of cancer biomarkers with potential preclinical and clinical applications. PMID:23335551

Ablation dynamics - from absorption to heat accumulation/ultra-fast laser matter interaction

NASA Astrophysics Data System (ADS)

Kramer, Thorsten; Remund, Stefan; Jäggi, Beat; Schmid, Marc; Neuenschwander, Beat

2018-05-01

Ultra-short laser radiation is used in manifold industrial applications today. Although state-of-the-art laser sources are providing an average power of 10-100 W with repetition rates of up to several megahertz, most applications do not benefit from it. On the one hand, the processing speed is limited to some hundred millimeters per second by the dynamics of mechanical axes or galvanometric scanners. On the other hand, high repetition rates require consideration of new physical effects such as heat accumulation and shielding that might reduce the process efficiency. For ablation processes, process efficiency can be expressed by the specific removal rate, ablated volume per time, and average power. The analysis of the specific removal rate for different laser parameters, like average power, repetition rate or pulse duration, and process parameters, like scanning speed or material, can be used to find the best operation point for microprocessing applications. Analytical models and molecular dynamics simulations based on the so-called two-temperature model reveal the causes for the appearance of limiting physical effects. The findings of models and simulations can be used to take advantage and optimize processing strategies.

Development and Characterization of Liquid Crystal-Gold Nanoparticle Hybrid Materials for Optical Applications

NASA Astrophysics Data System (ADS)

Quint, Makiko T.

Hybrid material, mixtures of two or more materials with new properties, represents an exciting class of new materials for a variety of potential applications such as displays, optoelectronics, and sensors due to their unique physical and optical properties. The scope of this dissertation is to produce two new plasmonic applications by combining liquid crystals with gold nanoparticles. The first application is gold nanoparticle coated liquid crystal thin film. Most liquid crystal (LC) thin films require external voltage to reorient LC molecules. Recent advances in optical controlling technology of LC molecule behavior, resulting in the reduction of energy consumption, have stimulated research and development of new LC thin films. In order to re-orient LC molecules by just using light, the common approach is to include either a photo-responsive LC host, one that require high power light and severely narrows the range of usable materials, or add photo-active dye or polymer layer, photodegradation over time. Our work designing an all-optical method for LC re-orientation that overcomes all the limitations mentioned above. We have successfully both in- and out-of-plane spatial orientation of nematic liquid crystal (LC) molecules by leveraging the highly localized electric fields produced in the near-field regime of a gold nanoparticle (AuNP) layer. This re-orientation of LC molecules in thin LC-AuNP film is all-optical, driven by a small resonance excitation power with the localized surface plasmon absorption of the AuNPs at room temperature. The second application is LC mediated nano-assembled gold microcapsules. This application has a potential in controlled-release cargo-style delivery system. Targeted delivery systems with controlled release mechanisms have been the subject of extensive research more than fifty years. One is to control the release process remotely by using optical excitation. Optical actuation of delivery capsules, which plasmonic nanoparticle such as gold, allows rapid release at specific locations and uses the photothermal effect to unload contents. Almost all gold-based delivery applications including Au coated nanocrystals or AuNPs with soft materials like gels and polymers are not suitable for control release applications in real life since these applications do not provide robust leakage-free containment lower than the American National Standards Institute (ANSI) maximum permissible light exposure limit. We have successfully managed the difficulties mentioned above and produced a new gold-based delivery application. The application is spherical capsules with a densely packed wall of AuNPs. The rigid capsule wall allows encapsulation of cargo that can be contained, virtually leakage-free, over several months. Further, by leveraging LSPR of AuNPs, we can rupture the microshells using optical excitation with ultralow power (< 2 mW), controllably and rapidly releasing the encapsulated contents in less than 5 seconds. Our results exhibiting the capture and optically regulated release of encapsulated substances are a novel platform that combines controlled-release cargo-style delivery and photothermal therapy in one versatile and multifunctional unit. Both our applications are overcoming current limitations and promising future research directions towards the next generation of LC-AuNPs hybrid material research and developments.

40 CFR 439.44 - Effluent limitations attainable by the application of best available technology economically...

Code of Federal Regulations, 2014 CFR

2014-07-01

... application of best available technology economically achievable (BAT). 439.44 Section 439.44 Protection of... limitations attainable by the application of best available technology economically achievable (BAT). Except... achieve the following effluent limitations representing the application of BAT: The limitations for COD...

40 CFR 432.123 - Effluent limitations attainable by the application of the best available technology economically...

Code of Federal Regulations, 2014 CFR

2014-07-01

... application of the best available technology economically achievable (BAT). 432.123 Section 432.123 Protection... limitations attainable by the application of the best available technology economically achievable (BAT... the following effluent limitations representing the application of BAT: Effluent Limitations [BAT...

40 CFR 432.23 - Effluent limitations attainable by the application of the best available technology economically...

Code of Federal Regulations, 2013 CFR

2013-07-01

... application of the best available technology economically achievable (BAT). 432.23 Section 432.23 Protection... limitations attainable by the application of the best available technology economically achievable (BAT... effluent limitations representing the application of BAT: Limitations for ammonia (as N) and total nitrogen...

40 CFR 432.23 - Effluent limitations attainable by the application of the best available technology economically...

Code of Federal Regulations, 2012 CFR

2012-07-01

... application of the best available technology economically achievable (BAT). 432.23 Section 432.23 Protection... limitations attainable by the application of the best available technology economically achievable (BAT... effluent limitations representing the application of BAT: Limitations for ammonia (as N) and total nitrogen...

40 CFR 437.33 - Effluent limitations attainable by the application of the best available technology economically...

Code of Federal Regulations, 2011 CFR

2011-07-01

... application of the best available technology economically achievable (BAT). 437.33 Section 437.33 Protection... limitations attainable by the application of the best available technology economically achievable (BAT... this subpart must achieve limitations representing the application of BAT: Limitations for copper, zinc...

40 CFR 432.43 - Effluent limitations attainable by the application of the best available technology economically...

Code of Federal Regulations, 2012 CFR

2012-07-01

... application of the best available technology economically achievable (BAT). 432.43 Section 432.43 Protection... limitations attainable by the application of the best available technology economically achievable (BAT... effluent limitations representing the application of BAT: Limitations for ammonia (as N) and total nitrogen...

40 CFR 432.123 - Effluent limitations attainable by the application of the best available technology economically...

Code of Federal Regulations, 2013 CFR

2013-07-01

... application of the best available technology economically achievable (BAT). 432.123 Section 432.123 Protection... limitations attainable by the application of the best available technology economically achievable (BAT... the following effluent limitations representing the application of BAT: Effluent Limitations [BAT...

40 CFR 444.15 - Effluent limitations attainable by the application of the best available technology economically...

Code of Federal Regulations, 2011 CFR

2011-07-01

... application of the best available technology economically achievable (BAT). 444.15 Section 444.15 Protection... limitations attainable by the application of the best available technology economically achievable (BAT... must achieve the following effluent limitations representing the application of BAT: Limitations for...

40 CFR 432.33 - Effluent limitations attainable by the application of the best available technology economically...

Code of Federal Regulations, 2012 CFR

2012-07-01

... application of the best available technology economically achievable (BAT). 432.33 Section 432.33 Protection... limitations attainable by the application of the best available technology economically achievable (BAT... effluent limitations representing the application of BAT: the limitations for ammonia (as N) and total...

40 CFR 439.44 - Effluent limitations attainable by the application of best available technology economically...

Code of Federal Regulations, 2013 CFR

2013-07-01

... application of best available technology economically achievable (BAT). 439.44 Section 439.44 Protection of... limitations attainable by the application of best available technology economically achievable (BAT). Except... achieve the following effluent limitations representing the application of BAT: The limitations for COD...

40 CFR 432.43 - Effluent limitations attainable by the application of the best available technology economically...

Code of Federal Regulations, 2014 CFR

2014-07-01

... application of the best available technology economically achievable (BAT). 432.43 Section 432.43 Protection... limitations attainable by the application of the best available technology economically achievable (BAT... effluent limitations representing the application of BAT: Limitations for ammonia (as N) and total nitrogen...

40 CFR 437.33 - Effluent limitations attainable by the application of the best available technology economically...

Code of Federal Regulations, 2010 CFR

2010-07-01

... application of the best available technology economically achievable (BAT). 437.33 Section 437.33 Protection... limitations attainable by the application of the best available technology economically achievable (BAT... this subpart must achieve limitations representing the application of BAT: Limitations for copper, zinc...

40 CFR 432.23 - Effluent limitations attainable by the application of the best available technology economically...

Code of Federal Regulations, 2014 CFR

2014-07-01

... application of the best available technology economically achievable (BAT). 432.23 Section 432.23 Protection... limitations attainable by the application of the best available technology economically achievable (BAT... effluent limitations representing the application of BAT: Limitations for ammonia (as N) and total nitrogen...

40 CFR 444.15 - Effluent limitations attainable by the application of the best available technology economically...

Code of Federal Regulations, 2010 CFR

2010-07-01

... application of the best available technology economically achievable (BAT). 444.15 Section 444.15 Protection... limitations attainable by the application of the best available technology economically achievable (BAT... must achieve the following effluent limitations representing the application of BAT: Limitations for...

40 CFR 432.33 - Effluent limitations attainable by the application of the best available technology economically...

Code of Federal Regulations, 2013 CFR

2013-07-01

... application of the best available technology economically achievable (BAT). 432.33 Section 432.33 Protection... limitations attainable by the application of the best available technology economically achievable (BAT... effluent limitations representing the application of BAT: the limitations for ammonia (as N) and total...

40 CFR 439.44 - Effluent limitations attainable by the application of best available technology economically...

Code of Federal Regulations, 2012 CFR

2012-07-01

... application of best available technology economically achievable (BAT). 439.44 Section 439.44 Protection of... limitations attainable by the application of best available technology economically achievable (BAT). Except... achieve the following effluent limitations representing the application of BAT: The limitations for COD...

40 CFR 432.43 - Effluent limitations attainable by the application of the best available technology economically...

Code of Federal Regulations, 2013 CFR

2013-07-01

... application of the best available technology economically achievable (BAT). 432.43 Section 432.43 Protection... limitations attainable by the application of the best available technology economically achievable (BAT... effluent limitations representing the application of BAT: Limitations for ammonia (as N) and total nitrogen...

40 CFR 432.33 - Effluent limitations attainable by the application of the best available technology economically...

Code of Federal Regulations, 2014 CFR

2014-07-01

... application of the best available technology economically achievable (BAT). 432.33 Section 432.33 Protection... limitations attainable by the application of the best available technology economically achievable (BAT... effluent limitations representing the application of BAT: the limitations for ammonia (as N) and total...

40 CFR 432.123 - Effluent limitations attainable by the application of the best available technology economically...

Code of Federal Regulations, 2012 CFR

2012-07-01

... application of the best available technology economically achievable (BAT). 432.123 Section 432.123 Protection... limitations attainable by the application of the best available technology economically achievable (BAT... the following effluent limitations representing the application of BAT: Effluent Limitations [BAT...

Anticipating epileptic seizures: from mathematics to clinical applications.

PubMed

Le Van Quyen, Michel

2005-02-01

The study of dynamical changes in the neural activity preceding an epileptic seizure allows the characterization of a preictal state several minutes prior to seizure onset. This opens new perspectives for studying the mechanisms of ictogenesis as well as for possible therapeutic interventions that represent a major breakthrough. In this review we present and discuss the results from our group in this domain using nonlinear analysis of brain signals, as well as its limitation and open questions.

Evaluation of Rhizobium tropici-derived Biopolymer for Erosion Control of Protective Berms. Field Study: Iowa Army Ammunition Plant

DTIC Science & Technology

2016-06-01

for several cyanobacteria (Hu et al. 2003) as well as for EPS in clay soil (Nugent et al. 2009). The adhesion, water retention, and protective...exopolymers on the liquid limit of clays and its engineering applications. Transportation Research Record: Journal of the Transportation Research...Development of progressive failure in sensitive clay slopes. Canadian Geotechnical Journal 49: 782-795. Rushing, J. F., and J. K. Newman., 2010

Highly efficient Cas9-mediated transcriptional programming

DOE PAGES

Chavez, Alejandro; Scheiman, Jonathan; Vora, Suhani; ...

2015-03-02

The RNA-guided nuclease Cas9 can be reengineered as a programmable transcription factor. However, modest levels of gene activation have limited potential applications. Here we describe an improved transcriptional regulator through the rational design of a tripartite activator, VP64-p65-Rta (VPR), fused to nuclease-null Cas9. Here, we demonstrate its utility in activating endogenous coding and non-coding genes, targeting several genes simultaneously and stimulating neuronal differentiation of human induced pluripotent stem cells (iPSCs).

Fast and Sensitive Solution-Processed Visible-Blind Perovskite UV Photodetectors.

PubMed

Adinolfi, Valerio; Ouellette, Olivier; Saidaminov, Makhsud I; Walters, Grant; Abdelhady, Ahmed L; Bakr, Osman M; Sargent, Edward H

2016-09-01

The first visible-blind UV photodetector based on MAPbCl3 integrated on a substrate exhibits excellent performance, with responsivities reaching 18 A W(-1) below 400 nm and imaging-compatible response times of 1 ms. This is achieved by using substrate-integrated single crystals, thus overcoming the severe limitations affecting thin films and offering a new application of efficient, solution-processed, visible-transparent perovskite optoelectronics. © 2016 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

RF-powered BIONs for stimulation and sensing.

PubMed

Loeb, G E; Richmond, F J R; Singh, J; Peck, R A; Tan, W; Zou, Q; Sachs, N

2004-01-01

Virtually all bodily functions are controlled by electrical signals in nerves and muscles. Electrical stimulation can restore missing signals but this has been difficult to achieve practically because of limitations in the bioelectric interfaces. Wireless, injectable microdevices are versatile, robust and relatively inexpensive to implant in a variety of sites and applications. Several variants are now in clinical use or under development to perform stimulation and/or sensing functions and to operate autonomously or with continuous coordination and feedback control.

Freedom to box.

PubMed Central

Warburton, N

1998-01-01

The british Medical Association wants to criminalise all boxing. This article examines the logic of the arguments it uses and finds them wanting. The move from medical evidence about the risk of brain damage to the conclusion that boxing should be banned is not warranted. The BMA's arguments are a combination of inconsistent paternalism and legal moralism. Consistent application of the principles implicit in the BMA's arguments would lead to absurd consequences and to severe limitations being put on individual freedom. PMID:9549684

Assessment of scaffold porosity: the new route of micro-CT.

PubMed

Bertoldi, Serena; Farè, Silvia; Tanzi, Maria Cristina

2011-01-01

A complete morphologic characterization of porous scaffolds for tissue engineering application is fundamental, as the architectural parameters, in particular porosity, strongly affect the mechanical and biological performance of the structures. Therefore, appropriate techniques for this purpose need to be selected. Several techniques for the assessment of scaffold porosity have been proposed, including Scanning Electron Microscopy observation, mercury and liquid extrusion porosimetry, gas pycnometry, and capillary flow porometry. Each of these techniques has several drawbacks and, a combination of different techniques is often required so as to achieve an in depth study of the morphologic properties of the scaffold. A single technique is often limited and suitable only for the assessment of a specific parameter. To overcome this limit, the most attractive option would be a single nondestructive technique, yet capable of providing a comprehensive set of data. It appears that micro-computed tomography (micro-CT) can potentially fulfill this role. Initially developed to characterize the 3D trabecular microarchitecture of bone, its use has been recently exploited by researchers for the morphologic characterization of porous biomaterials, as it enables obtaining a full assessment of the porous structures both in terms of pore size and interconnected porosity. This review aims to explore the use of micro-CT in scaffold characterization, comparing it with other previously developed techniques; we also focus on the contribution of this innovative tool to the development of scaffold-based tissue engineering application.

Study of the kinematic and load sharing properties of wormgearing with non-symmetric tooth profiles

NASA Technical Reports Server (NTRS)

Sun, D. C.; Yuan, Qin

1995-01-01

The geometry of non-symmetric tooth profiles, i.e. tooth profiles with different pressure angles on the two sides of the tooth, is studied. A feasible non-symmetric tooth profile for application in helicopter transmissions is laid out as the best compromise among several conflicting factors. The non-symmetric tooth profile is then compared with the symmetric tooth profile studied previously. Based on the detailed comparisons it is concluded that the use of the non-symmetric tooth profile would severely limit the face width of the worm, consequently reduce the number of meshing teeth and cause much higher normal load on the individual gear teeth.

Effects and Effectiveness of Telemedicine

PubMed Central

Grigsby, Jim; Kaehny, Margaret M.; Sandberg, Elliot J.; Schlenker, Robert E.; Shaughnessy, Peter W.

1995-01-01

The use of telemedicine has recently undergone rapid growth and proliferation. Although the feasibility of many applications has been tested for nearly 30 years, data concerning the costs, effects, and effectiveness of telemedicine are limited. Consequently, the development of a strategy for coverage, payment, and utilization policy has been hindered. Telemedicine continues to expand, and pressure for policy development increases in the context of Federal budget cuts and major changes in health service financing. This article reviews the literature on the effects and medical effectiveness of telemedicine. It concludes with several recommendations for research, followed by a discussion of several specific questions, the answers to which might have a bearing on policy development. PMID:10153466

A Review of Recent Developments in X-Ray Diagnostics for Turbulent and Optically Dense Rocket Sprays

NASA Technical Reports Server (NTRS)

Radke, Christopher; Halls, Benjamin; Kastengren, Alan; Meyer, Terrence

2017-01-01

Highly efficient mixing and atomization of fuel and oxidizers is an important factor in many propulsion and power generating applications. To better quantify breakup and mixing in atomizing sprays, several diagnostic techniques have been developed to collect droplet information and spray statistics. Several optical based techniques, such as Ballistic Imaging and SLIPI have previously demonstrated qualitative measurements in optically dense sprays, however these techniques have produced limited quantitative information in the near injector region. To complement to these advances, a recent wave of developments utilizing synchrotron based x-rays have been successful been implemented facilitating the collection of quantitative measurements in optically dense sprays.

Two-colour live-cell nanoscale imaging of intracellular targets

NASA Astrophysics Data System (ADS)

Bottanelli, Francesca; Kromann, Emil B.; Allgeyer, Edward S.; Erdmann, Roman S.; Wood Baguley, Stephanie; Sirinakis, George; Schepartz, Alanna; Baddeley, David; Toomre, Derek K.; Rothman, James E.; Bewersdorf, Joerg

2016-03-01

Stimulated emission depletion (STED) nanoscopy allows observations of subcellular dynamics at the nanoscale. Applications have, however, been severely limited by the lack of a versatile STED-compatible two-colour labelling strategy for intracellular targets in living cells. Here we demonstrate a universal labelling method based on the organic, membrane-permeable dyes SiR and ATTO590 as Halo and SNAP substrates. SiR and ATTO590 constitute the first suitable dye pair for two-colour STED imaging in living cells below 50 nm resolution. We show applications with mitochondria, endoplasmic reticulum, plasma membrane and Golgi-localized proteins, and demonstrate continuous acquisition for up to 3 min at 2-s time resolution.

[Current status and clinical application prospect of Akabane's test].

PubMed

Wang, Wenjie; Du, Yanjun

2016-06-12

The Akabane's test is one of the meridian diagnostic methods. Compared with the current meridian diagnostic methods, it has the advantages of convenience and efficiency, but it also has several disadvantages such as the accuracy is difficult to control, the outcome interpretation is limited, etc. In this paper, the influence factors of Akabane's test were analyzed one by one, especially proposed personal opinion on outcome interpretation, which could ascertain the location and nature of disease, leading to disease syndrome. With accurate syndrome, the treatment plan could be established. The application prospect of Akabane's test was initially explored, and it was proposed that wearable automation equipment could be one of the development directions.

Design of SERS nanoprobes for Raman imaging: materials, critical factors and architectures.

PubMed

Li, Mingwang; Qiu, Yuanyuan; Fan, Chenchen; Cui, Kai; Zhang, Yongming; Xiao, Zeyu

2018-05-01

Raman imaging yields high specificity and sensitivity when compared to other imaging modalities, mainly due to its fingerprint signature. However, intrinsic Raman signals are weak, thus limiting medical applications of Raman imaging. By adsorbing Raman molecules onto specific nanostructures such as noble metals, Raman signals can be significantly enhanced, termed surface-enhanced Raman scattering (SERS). Recent years have witnessed great interest in the development of SERS nanoprobes for Raman imaging. Rationally designed SERS nanoprobes have greatly enhanced Raman signals by several orders of magnitude, thus showing great potential for biomedical applications. In this review we elaborate on recent progress in design strategies with emphasis on material properties, modifying factors, and structural parameters.

[Primary prevention of sudden cardiac death through a wearable cardioverter-defibrillator].

PubMed

Gabrielli, Domenico; Benvenuto, Manuela; Baroni, Matteo; Oliva, Fabrizio; Capucci, Alessandro

2015-01-01

Nowadays, the implantable cardioverter-defibrillator is the gold standard for the prevention of sudden cardiac death due to tachyarrhythmias. However, its use is not free from short and long-term risks. In the last years, the wearable cardioverter-defibrillator (WCD) has become a widespread option for patients who need a safe and reversible protection against ventricular tachyarrhythmias. Notwithstanding this, its everyday application is restricted by several limitations, including the risk of inappropriate shocks, the device size and the need for strict compliance of both patients and caregivers. In this review, we report the most relevant literature data on WCD usage along with the main fields of applications and future perspectives.

Genetic correction using engineered nucleases for gene therapy applications.

PubMed

Li, Hongmei Lisa; Nakano, Takao; Hotta, Akitsu

2014-01-01

Genetic mutations in humans are associated with congenital disorders and phenotypic traits. Gene therapy holds the promise to cure such genetic disorders, although it has suffered from several technical limitations for decades. Recent progress in gene editing technology using tailor-made nucleases, such as meganucleases (MNs), zinc finger nucleases (ZFNs), TAL effector nucleases (TALENs) and, more recently, CRISPR/Cas9, has significantly broadened our ability to precisely modify target sites in the human genome. In this review, we summarize recent progress in gene correction approaches of the human genome, with a particular emphasis on the clinical applications of gene therapy. © 2013 The Authors Development, Growth & Differentiation © 2013 Japanese Society of Developmental Biologists.

Super-resolution from single photon emission: toward biological application

NASA Astrophysics Data System (ADS)

Moreva, E.; Traina, P.; Forneris, J.; Ditalia Tchernij, S.; Guarina, L.; Franchino, C.; Picollo, F.; Ruo Berchera, I.; Brida, G.; Degiovanni, I. P.; Carabelli, V.; Olivero, P.; Genovese, M.

2017-08-01

Properties of quantum light represent a tool for overcoming limits of classical optics. Several experiments have demonstrated this advantage ranging from quantum enhanced imaging to quantum illumination. In this work, experimental demonstration of quantum-enhanced resolution in confocal fluorescence microscopy will be presented. This is achieved by exploiting the non-classical photon statistics of fluorescence emission of single nitrogen-vacancy (NV) color centers in diamond. By developing a general model of super-resolution based on the direct sampling of the kth-order autocorrelation function of the photoluminescence signal, we show the possibility to resolve, in principle, arbitrarily close emitting centers. Finally, possible applications of NV-based fluorescent nanodiamonds in biosensing and future developments will be presented.

3D-printed Bioanalytical Devices

PubMed Central

Bishop, Gregory W; Satterwhite-Warden, Jennifer E; Kadimisetty, Karteek; Rusling, James F

2016-01-01

While 3D printing technologies first appeared in the 1980s, prohibitive costs, limited materials, and the relatively small number of commercially available printers confined applications mainly to prototyping for manufacturing purposes. As technologies, printer cost, materials, and accessibility continue to improve, 3D printing has found widespread implementation in research and development in many disciplines due to ease-of-use and relatively fast design-to-object workflow. Several 3D printing techniques have been used to prepare devices such as milli- and microfluidic flow cells for analyses of cells and biomolecules as well as interfaces that enable bioanalytical measurements using cellphones. This review focuses on preparation and applications of 3D-printed bioanalytical devices. PMID:27250897

Virtual reality visualization algorithms for the ALICE high energy physics experiment on the LHC at CERN

NASA Astrophysics Data System (ADS)

Myrcha, Julian; Trzciński, Tomasz; Rokita, Przemysław

2017-08-01

Analyzing massive amounts of data gathered during many high energy physics experiments, including but not limited to the LHC ALICE detector experiment, requires efficient and intuitive methods of visualisation. One of the possible approaches to that problem is stereoscopic 3D data visualisation. In this paper, we propose several methods that provide high quality data visualisation and we explain how those methods can be applied in virtual reality headsets. The outcome of this work is easily applicable to many real-life applications needed in high energy physics and can be seen as a first step towards using fully immersive virtual reality technologies within the frames of the ALICE experiment.

Investigation of miniaturized radioisotope thermionic power generation for general use

NASA Astrophysics Data System (ADS)

Duzik, Adam J.; Choi, Sang H.

2016-04-01

Radioisotope thermoelectric generators (RTGs) running off the radioisotope Pu238 are the current standard in deep space probe power supplies. While reliable, these generators are very inefficient, operating at only ~7% efficiency. As an alternative, more efficient radioisotope thermionic emission generators (RTIGs) are being explored. Like RTGs, current RTIGs concepts use exotic materials for the emitter, limiting applicability to space and other niche applications. The high demand for long-lasting mobile power sources would be satisfied if RTIGs could be produced inexpensively. This work focuses on exposing several common materials, such as Al, stainless steel, W, Si, and Cu, to elevated temperatures under vacuum to determine the efficiency of each material as inexpensive replacements for thermoelectric materials.

Water recovery and solid waste processing for aerospace and domestic applications. Volume 1: Final report

NASA Technical Reports Server (NTRS)

Murray, R. W.

1973-01-01

A comprehensive study of advanced water recovery and solid waste processing techniques employed in both aerospace and domestic or commercial applications is reported. A systems approach was used to synthesize a prototype system design of an advanced water treatment/waste processing system. Household water use characteristics were studied and modified through the use of low water use devices and a limited amount of water reuse. This modified household system was then used as a baseline system for development of several water treatment waste processing systems employing advanced techniques. A hybrid of these systems was next developed and a preliminary design was generated to define system and hardware functions.

Noiseless coding for the magnetometer

NASA Technical Reports Server (NTRS)

Rice, Robert F.; Lee, Jun-Ji

1987-01-01

Future unmanned space missions will continue to seek a full understanding of magnetic fields throughout the solar system. Severely constrained data rates during certain portions of these missions could limit the possible science return. This publication investigates the application of universal noiseless coding techniques to more efficiently represent magnetometer data without any loss in data integrity. Performance results indicated that compression factors of 2:1 to 6:1 can be expected. Feasibility for general deep space application was demonstrated by implementing a microprocessor breadboard coder/decoder using the Intel 8086 processor. The Comet Rendezvous Asteroid Flyby mission will incorporate these techniques in a buffer feedback, rate-controlled configuration. The characteristics of this system are discussed.

Safer energetic materials by a nanotechnological approach.

PubMed

Siegert, Benny; Comet, Marc; Spitzer, Denis

2011-09-01

Energetic materials - explosives, thermites, populsive powders - are used in a variety of military and civilian applications. Their mechanical and electrostatic sensitivity is high in many cases, which can lead to accidents during handling and transport. These considerations limit the practical use of some energetic materials despite their good performance. For industrial applications, safety is one of the main criteria for selecting energetic materials. The sensitivity has been regarded as an intrinsic property of a substance for a long time. However, in recent years, several approaches to lower the sensitivity of a given substance, using nanotechnology and materials engineering, have been described. This feature article gives an overview over ways to prepare energetic (nano-)materials with a lower sensitivity.

Li- and Mn-Rich Cathode Materials: Challenges to Commercialization

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

Zheng, Jianming; Myeong, Seungjun; Cho, Woongrae

2016-12-14

The lithium- and manganese-rich (LMR) layered structure cathode exhibit one of the highest specific energy (~900 Wh kg-1) among all the cathode materials. However, the practical applications of LMR cathodes are still hindered by several significant challenges including voltage fade, large initial capacity loss, poor rate capability and limited cycle life. Herein, we review the recent progresses and understandings on the application of LMR cathode materials from practical point of view. Several key parameters of LMR cathodes that affect the LMR/graphite full cell operation are systematically analysed. These factors include the first cycle capacity loss, voltage fade, powder tap density,more » electrode density of LMR based cathode etc. New approaches to minimize the detrimental effect of these factors are highlighted in this work. We also provided the perspectives for the future research on LMR cathode materials, focusing on addressing the fundamental problems of LMR cathodes while always keeping practical considerations in mind.« less

Role of low-level laser therapy on the cardiac remodeling after myocardial infarction: A systematic review of experimental studies.

PubMed

Carlos, Fernando Pereira; Gradinetti, Vanessa; Manchini, Martha; de Tarso Camillo de Carvalho, Paulo; Silva, José Antonio; Girardi, Adriana Castello Costa; Leal-Junior, Ernesto Cesar Pinto; Bocalini, Danilo Sales; Vieira, Stella; Antonio, Ednei Luiz; Tucci, Paulo; Serra, Andrey Jorge

2016-04-15

We systematically reviewed the role of low-level laser therapy (LLLT) in cardiac remodeling after myocardial infarction. Literatures were systematically searched in several electronic databases. We included only studies with a well-standardized coronary occlusion model in vivo LLLT application. After screening, 14 studies were eligible for review. The study heterogeneity was described in terms of rationality, gender, irradiation parameters, treatment numbers and moment of LLLT application. Three studies showed a null role of LLLT on infarct size, and only one study found positive LLLT effects on the cardiac performance. The cardioprotective role of LLLT was mediated by anti-inflammatory, pro-angiogenic and anti-oxidant actions. The reduction in infarct size is a major finding. The LLLT cardioprotection may be mediated by several molecular and cellular mechanisms. Although these results are exciting, there are many limitations that must be resolved before LLLT clinical trials. Copyright © 2016 Elsevier Inc. All rights reserved.

A Summary of the NASA Lightning Nitrogen Oxides Model (LNOM) and Recent Results

NASA Technical Reports Server (NTRS)

Koshak, William; Peterson, Harld

2011-01-01

The NASA Marshall Space Flight Center introduced the Lightning Nitrogen Oxides Model (LNOM) a couple of years ago to combine routine state-of-the-art measurements of lightning with empirical laboratory results of lightning NOx production. The routine measurements included VHF lightning source data [such as from the North Alabama Lightning Mapping Array (LMA)], and ground flash location, peak current, and stroke multiplicity data from the National Lightning Detection Network(TradeMark) (NLDN). Following these initial runs of LNOM, the model was updated to include several non-return stroke lightning NOx production mechanisms, and provided the impact of lightning NOx on an August 2006 run of CMAQ. In this study, we review the evolution of the LNOM in greater detail and discuss the model?s latest upgrades and applications. Whereas previous applications were limited to five summer months of data for North Alabama thunderstorms, the most recent LNOM analyses cover several years. The latest statistics of ground and cloud flash NOx production are provided.

Review of advanced imaging techniques

PubMed Central

Chen, Yu; Liang, Chia-Pin; Liu, Yang; Fischer, Andrew H.; Parwani, Anil V.; Pantanowitz, Liron

2012-01-01

Pathology informatics encompasses digital imaging and related applications. Several specialized microscopy techniques have emerged which permit the acquisition of digital images (“optical biopsies”) at high resolution. Coupled with fiber-optic and micro-optic components, some of these imaging techniques (e.g., optical coherence tomography) are now integrated with a wide range of imaging devices such as endoscopes, laparoscopes, catheters, and needles that enable imaging inside the body. These advanced imaging modalities have exciting diagnostic potential and introduce new opportunities in pathology. Therefore, it is important that pathology informaticists understand these advanced imaging techniques and the impact they have on pathology. This paper reviews several recently developed microscopic techniques, including diffraction-limited methods (e.g., confocal microscopy, 2-photon microscopy, 4Pi microscopy, and spatially modulated illumination microscopy) and subdiffraction techniques (e.g., photoactivated localization microscopy, stochastic optical reconstruction microscopy, and stimulated emission depletion microscopy). This article serves as a primer for pathology informaticists, highlighting the fundamentals and applications of advanced optical imaging techniques. PMID:22754737

Electrocatalytic Metal-Organic Frameworks for Energy Applications.

PubMed

Downes, Courtney A; Marinescu, Smaranda C

2017-11-23

With the global energy demand expected to increase drastically over the next several decades, the development of a sustainable energy system to meet this increase is paramount. Renewable energy sources can be coupled with electrochemical conversion processes to store energy in chemical bonds. To promote these difficult transformations, electrocatalysts that operate at high conversion rates and efficiency are required. Metal-organic frameworks (MOFs) have emerged as a promising class of materials; however, the insulating nature of MOFs has limited their application as electrocatalysts. The recent development of conductive MOFs has led to several electrocatalytic MOFs that display activity comparable to that of the best-performing heterogeneous catalysts. Although many electrocatalytic MOFs exhibit low activity and stability, the few successful examples highlight the possibility of MOF electrocatalysts as replacements for noble-metal-based catalysts in commercial energy-converting devices. We review herein the use of pristine MOFs as electrocatalysts to facilitate important energy-related reactions. © 2017 Wiley-VCH Verlag GmbH & Co. KGaA, Weinheim.

High Temperature, High Power Piezoelectric Composite Transducers

PubMed Central

Lee, Hyeong Jae; Zhang, Shujun; Bar-Cohen, Yoseph; Sherrit, StewarT.

2014-01-01

Piezoelectric composites are a class of functional materials consisting of piezoelectric active materials and non-piezoelectric passive polymers, mechanically attached together to form different connectivities. These composites have several advantages compared to conventional piezoelectric ceramics and polymers, including improved electromechanical properties, mechanical flexibility and the ability to tailor properties by using several different connectivity patterns. These advantages have led to the improvement of overall transducer performance, such as transducer sensitivity and bandwidth, resulting in rapid implementation of piezoelectric composites in medical imaging ultrasounds and other acoustic transducers. Recently, new piezoelectric composite transducers have been developed with optimized composite components that have improved thermal stability and mechanical quality factors, making them promising candidates for high temperature, high power transducer applications, such as therapeutic ultrasound, high power ultrasonic wirebonding, high temperature non-destructive testing, and downhole energy harvesting. This paper will present recent developments of piezoelectric composite technology for high temperature and high power applications. The concerns and limitations of using piezoelectric composites will also be discussed, and the expected future research directions will be outlined. PMID:25111242

A deviation based assessment methodology for multiple machine health patterns classification and fault detection

NASA Astrophysics Data System (ADS)

Jia, Xiaodong; Jin, Chao; Buzza, Matt; Di, Yuan; Siegel, David; Lee, Jay

2018-01-01

Successful applications of Diffusion Map (DM) in machine failure detection and diagnosis have been reported in several recent studies. DM provides an efficient way to visualize the high-dimensional, complex and nonlinear machine data, and thus suggests more knowledge about the machine under monitoring. In this paper, a DM based methodology named as DM-EVD is proposed for machine degradation assessment, abnormality detection and diagnosis in an online fashion. Several limitations and challenges of using DM for machine health monitoring have been analyzed and addressed. Based on the proposed DM-EVD, a deviation based methodology is then proposed to include more dimension reduction methods. In this work, the incorporation of Laplacian Eigen-map and Principal Component Analysis (PCA) are explored, and the latter algorithm is named as PCA-Dev and is validated in the case study. To show the successful application of the proposed methodology, case studies from diverse fields are presented and investigated in this work. Improved results are reported by benchmarking with other machine learning algorithms.

High-content screening for the discovery of pharmacological compounds: advantages, challenges and potential benefits of recent technological developments.

PubMed

Soleilhac, Emmanuelle; Nadon, Robert; Lafanechere, Laurence

2010-02-01

Screening compounds with cell-based assays and microscopy image-based analysis is an approach currently favored for drug discovery. Because of its high information yield, the strategy is called high-content screening (HCS). This review covers the application of HCS in drug discovery and also in basic research of potential new pathways that can be targeted for treatment of pathophysiological diseases. HCS faces several challenges, however, including the extraction of pertinent information from the massive amount of data generated from images. Several proposed approaches to HCS data acquisition and analysis are reviewed. Different solutions from the fields of mathematics, bioinformatics and biotechnology are presented. Potential applications and limits of these recent technical developments are also discussed. HCS is a multidisciplinary and multistep approach for understanding the effects of compounds on biological processes at the cellular level. Reliable results depend on the quality of the overall process and require strong interdisciplinary collaborations.

Hierarchical virtual screening approaches in small molecule drug discovery.

PubMed

Kumar, Ashutosh; Zhang, Kam Y J

2015-01-01

Virtual screening has played a significant role in the discovery of small molecule inhibitors of therapeutic targets in last two decades. Various ligand and structure-based virtual screening approaches are employed to identify small molecule ligands for proteins of interest. These approaches are often combined in either hierarchical or parallel manner to take advantage of the strength and avoid the limitations associated with individual methods. Hierarchical combination of ligand and structure-based virtual screening approaches has received noteworthy success in numerous drug discovery campaigns. In hierarchical virtual screening, several filters using ligand and structure-based approaches are sequentially applied to reduce a large screening library to a number small enough for experimental testing. In this review, we focus on different hierarchical virtual screening strategies and their application in the discovery of small molecule modulators of important drug targets. Several virtual screening studies are discussed to demonstrate the successful application of hierarchical virtual screening in small molecule drug discovery. Copyright © 2014 Elsevier Inc. All rights reserved.

Electrokinetic-enhanced phytoremediation of soils: status and opportunities.

PubMed

Cameselle, Claudio; Chirakkara, Reshma A; Reddy, Krishna R

2013-10-01

Phytoremediation is a sustainable process in which green plants are used for the removal or elimination of contaminants in soils. Both organic and inorganic contaminants can be removed or degraded by growing plants by several mechanisms, namely phytoaccumulation, phytostabilization, phytodegradation, rhizofiltration and rhizodegradation. Phytoremediation has several advantages: it can be applied in situ over large areas, the cost is low, and the soil does not undergo significant damages. However, the restoration of a contaminated site by phytoremediation requires a long treatment time since the remediation depends on the growth and the biological cycles of the plant. It is only applicable for shallow depths within the reach of the roots, and the remediation efficiency largely depends on the physico-chemical properties of the soil and the bioavailability of the contaminants. The combination of phytoremediation and electrokinetics has been proposed in an attempt to avoid, in part, the limitations of phytoremediation. Basically, the coupled phytoremediation-electrokinetic technology consists of the application of a low intensity electric field to the contaminated soil in the vicinity of growing plants. The electric field may enhance the removal of the contaminants by increasing the bioavailability of the contaminants. Variables that affect the coupled technology are: the use of AC or DC current, voltage level and mode of voltage application (continuous or periodic), soil pH evolution, and the addition of facilitating agents to enhance the mobility and bioavailability of the contaminants. Several technical and practical challenges still remain that must be overcome through future research for successful application of this coupled technology at actual field sites. Copyright © 2013 Elsevier Ltd. All rights reserved.

Application of Optimization Techniques to Design of Unconventional Rocket Nozzle Configurations

NASA Technical Reports Server (NTRS)

Follett, W.; Ketchum, A.; Darian, A.; Hsu, Y.

1996-01-01

Several current rocket engine concepts such as the bell-annular tri-propellant engine, and the linear aerospike being proposed for the X-33 require unconventional three dimensional rocket nozzles which must conform to rectangular or sector shaped envelopes to meet integration constraints. These types of nozzles exist outside the current experience database, therefore, the application of efficient design methods for these propulsion concepts is critical to the success of launch vehicle programs. The objective of this work is to optimize several different nozzle configurations, including two- and three-dimensional geometries. Methodology includes coupling computational fluid dynamic (CFD) analysis to genetic algorithms and Taguchi methods as well as implementation of a streamline tracing technique. Results of applications are shown for several geometeries including: three dimensional thruster nozzles with round or super elliptic throats and rectangualar exits, two- and three-dimensional thrusters installed within a bell nozzle, and three dimensional thrusters with round throats and sector shaped exits. Due to the novel designs considered for this study, there is little experience which can be used to guide the effort and limit the design space. With a nearly infinite parameter space to explore, simple parametric design studies cannot possibly search the entire design space within the time frame required to impact the design cycle. For this reason, robust and efficient optimization methods are required to explore and exploit the design space to achieve high performance engine designs. Five case studies which examine the application of various techniques in the engineering environment are presented in this paper.

A Mach-Zender Holographic Microscope for Quantifying Bacterial Motility

NASA Astrophysics Data System (ADS)

Niraula, B.; Nadeau, J. L.; Serabyn, E.; Wallace, J. K.; Liewer, K.; Kuhn, J.; Graff, E.; Lindensmith, C.

2014-12-01

New microscopic techniques have revolutionized cell biology over the past two decades. However, there are still biological processes whose details elude us, especially those involving motility: e.g. feeding behavior of microorganisms in the ocean, or migration of cancer cells to form metastases. Imaging prokaryotes, which range in size from several hundred nm to a few microns, is especially challenging. An emerging technique to address these issues is Digital Holographic Microscopy (DHM). DHM is an imaging technique that uses the interference of light to record and reproduce three-dimensional magnified images of objects. This approach has several advantages over ordinary brightfield microscopy for fieldwork: a larger depth of field, hands-off operation, robustness regarding environmental conditions, and large sampling volumes with quantitative 3D records of motility behavior. Despite these promising features, real-time DHM was thought to be impractical for technological and computational reasons until recently, and there has so far been very limited application of DHM to biology. Most existing instruments are limited in performance by their particular (e.g. in-line, lens-less, phase-shifting) approach to holography. These limitations can be mitigated with an off-axis dual-path configuration. Here we describe the design and implementation of a design for a Mach-Zehnder-type holographic microscope with diffraction-limited lateral resolution, with intended applications in environmental microbiology. We have achieved sub-micron resolution and three-dimensional tracking of prokaryotic and eukaryotic test strains designed to represent different modes and speeds of microbial motility. Prokaryotes are Escherichia coli, Vibrio alginolyticus, and Bacillus subtilis. Each shows a characteristic motility pattern, as we illustrate in holographic videos in sample chambers 0.6 mm in depth. The ability to establish gradients of attractants with bacterial taxis towards the attractant is also established. The eukaryotic strains are Euglena gracilis, which demonstrates both phototaxis and geotaxis, and Paramecium micromultinucleatum. The challenges of optimizing resolution vs. field of view, and of handling the large volumes of data generated during holographic imaging, are discussed.

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

Litvinenko,V.; Yakimenko, V.

We propose undertaking a demonstration experiment on suppressing spontaneous undulator radiation from an electron beam at BNL's Accelerator Test Facility (ATF). We describe the method, the proposed layout, and a possible schedule. There are several advantages in strongly suppressing shot noise in the electron beam, and the corresponding spontaneous radiation. The self-amplified spontaneous (SASE) emission originating from shot noise in the electron beam is the main source of noise in high-gain FEL amplifiers. It may negatively affect several HG FEL applications ranging from single- to multi-stage HGHG FELs. SASE saturation also imposes a fundamental hard limit on the gain ofmore » an FEL amplifier in a coherent electron-cooling scheme. A novel active method for suppressing shot noise in relativistic electron beams by many orders-of-magnitude was recently proposed. While theoretically such strong suppression appears feasible, the performance and applicability of this novel method must be evaluated experimentally. Several practical questions about the proposed noise suppressor, such as 3D effects and/or sensitivity to the e-beam parameters also require experimental clarification. To do this, we propose here a proof-of-principle experiment using elements of the VISA FEL at BNL's Accelerator Test Facility.« less

Topical application of probiotics in skin: adhesion, antimicrobial and antibiofilm in vitro assays.

PubMed

Lopes, E G; Moreira, D A; Gullón, P; Gullón, B; Cardelle-Cobas, A; Tavaria, F K

2017-02-01

When skin dysbiosis occurs as a result of skin disorders, probiotics can act as modulators, restoring microbial balance. Several properties of selected probiotics were evaluated so that their topical application could be considered. Adhesion, antimicrobial, quorum sensing and antibiofilm assays were carried out with several probiotic strains and tested against selected skin pathogens. All tested strains displayed significant adhesion to keratin. All lactobacilli with the exception of Lactobacillus delbrueckii, showed antimicrobial activity against skin pathogens, mainly due to organic acid production. Most of them also prevented biofilm formation, but only Propioniferax innocua was able to break down mature biofilms. This study demonstrates that although all tested probiotics adhered to human keratin, they showed limited ability to prevent adhesion of some potential skin pathogens. Most of the tested probiotics successfully prevented biofilm formation, suggesting that they may be successfully used in the future as a complement to conventional therapies in the treatment of a range of skin disorders. The topically used probiotics may be a natural, targeted treatment approach to several skin disorders and a complement to conventional therapies which present many undesirable side effects. © 2016 The Society for Applied Microbiology.

Noise Attenuation Performance of a Helmholtz Resonator Array Consist of Several Periodic Parts

PubMed Central

Wu, Dizi; Zhang, Nan; Mak, Cheuk Ming; Cai, Chenzhi

2017-01-01

The acoustic performance of the ducted Helmholtz resonator (HR) system is analyzed theoretically and numerically. The periodic HR array could provide a wider noise attenuation band due to the coupling of the Bragg reflection and the HR’s resonance. However, the transmission loss achieved by a periodic HR array is mainly dependent on the number of HRs, which restricted by the available space in the longitudinal direction of the duct. The full distance along the longitudinal direction of the duct for HR’s installation is sometimes unavailable in practical applications. Only several pieces of the duct may be available for the installation. It is therefore that this paper concentrates on the acoustic performance of a HR array consisting of several periodic parts. The transfer matrix method and the Bragg theory are used to investigate wave propagation in the duct. The theoretical prediction results show good agreement with the Finite Element Method (FEM) simulation results. The present study provides a practical way in noise control application of ventilation ductwork system by utilizing the advantage of periodicity with the limitation of available completed installation length for HRs. PMID:28471383

Organic-inorganic composites designed for biomedical applications.

PubMed

Miyazaki, Toshiki; Ishikawa, Kunio; Shirosaki, Yuki; Ohtsuki, Chikara

2013-01-01

Several varieties of ceramics, such as Bioglass-type glasses, sintered hydroxyapatite and glass-ceramic A-W, exhibit specific biological affinity, i.e., direct bonding to surrounding bone, when implanted in bony defects. These bone-bonding ceramics are called bioactive ceramics and are utilized as important bone substitutes in the medical field. However, there is a limitation to their clinical applications because of their inappropriate mechanical properties. Natural bone takes a kind of organic-inorganic composite, where apatite nanocrystals are precipitated on collagen fibers. Therefore, problems with the bioactive ceramics can be solved by material design based on the composites. In this paper, current research topics on the development of bioactive organic-inorganic composites inspired by actual bone microstructure have been reviewed in correlation with preparation methods and various properties. Several kinds of inorganic components have been found to exhibit bioactivity in the body environment. Combination of the inorganic components with various organic polymers enables the development of bioactive organic-inorganic composites. In addition, novel biomedical applications of the composites to drug delivery systems, scaffolds for tissue regeneration and injectable biomaterials are available by combining drugs or biological molecules with appropriate control of its microstructure.

Decentralized Online Social Networks

NASA Astrophysics Data System (ADS)

Datta, Anwitaman; Buchegger, Sonja; Vu, Le-Hung; Strufe, Thorsten; Rzadca, Krzysztof

Current Online social networks (OSN) are web services run on logically centralized infrastructure. Large OSN sites use content distribution networks and thus distribute some of the load by caching for performance reasons, nevertheless there is a central repository for user and application data. This centralized nature of OSNs has several drawbacks including scalability, privacy, dependence on a provider, need for being online for every transaction, and a lack of locality. There have thus been several efforts toward decentralizing OSNs while retaining the functionalities offered by centralized OSNs. A decentralized online social network (DOSN) is a distributed system for social networking with no or limited dependency on any dedicated central infrastructure. In this chapter we explore the various motivations of a decentralized approach to online social networking, discuss several concrete proposals and types of DOSN as well as challenges and opportunities associated with decentralization.

Detection of β-Lactams and Chloramphenicol Residues in Raw Milk-Development and Application of an HPLC-DAD Method in Comparison with Microbial Inhibition Assays.

PubMed

Karageorgou, Eftychia; Christoforidou, Sofia; Ioannidou, Maria; Psomas, Evdoxios; Samouris, Georgios

2018-06-01

The present study was carried out to assess the detection sensitivity of four microbial inhibition assays (MIAs) in comparison with the results obtained by the High Performance Liquid Chromatography with Diode-Array Detection (HPLC-DAD) method for antibiotics of the β-lactam group and chloramphenicol in fortified raw milk samples. MIAs presented fairly good results when detecting β-lactams, whereas none were able to detect chloramphenicol at or above the permissible limits. HPLC analysis revealed high recoveries of examined compounds, whereas all detection limits observed were lower than their respective maximum residue limits (MRL) values. The extraction and clean-up procedure of antibiotics was performed by a modified matrix solid phase dispersion procedure using a mixture of Plexa by Agilent and QuEChERS as a sorbent. The HPLC method developed was validated, determining the accuracy, precision, linearity, decision limit, and detection capability. Both methods were used to monitor raw milk samples of several cows and sheep, obtained from producers in different regions of Greece, for the presence of examined antibiotic residues. Results obtained showed that MIAs could be used effectively and routinely to detect antibiotic residues in several milk types. However, in some cases, spoilage of milk samples revealed that the kits' sensitivity could be strongly affected, whereas this fact does not affect the effectiveness of HPLC-DAD analysis.

A New 3D Printing Strategy by Harnessing Deformation, Instability, and Fracture of Viscoelastic Inks.

PubMed

Yuk, Hyunwoo; Zhao, Xuanhe

2018-02-01

Direct ink writing (DIW) has demonstrated great potential as a multimaterial multifunctional fabrication method in areas as diverse as electronics, structural materials, tissue engineering, and soft robotics. During DIW, viscoelastic inks are extruded out of a 3D printer's nozzle as printed fibers, which are deposited into patterns when the nozzle moves. Hence, the resolution of printed fibers is commonly limited by the nozzle's diameter, and the printed pattern is limited by the motion paths. These limits have severely hampered innovations and applications of DIW 3D printing. Here, a new strategy to exceed the limits of DIW 3D printing by harnessing deformation, instability, and fracture of viscoelastic inks is reported. It is shown that a single nozzle can print fibers with resolution much finer than the nozzle diameter by stretching the extruded ink, and print various thickened or curved patterns with straight nozzle motions by accumulating the ink. A quantitative phase diagram is constructed to rationally select parameters for the new strategy. Further, applications including structures with tunable stiffening, 3D structures with gradient and programmable swelling properties, all printed with a single nozzle are demonstrated. The current work demonstrates that the mechanics of inks plays a critical role in developing 3D printing technology. © 2017 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

The randomised controlled trial design: unrecognized opportunities for health sciences librarianship.

PubMed

Eldredge, Jonathan D

2003-06-01

to describe the essential components of the Randomised Controlled Trial (RCT) and its major variations; to describe less conventional applications of the RCT design found in the health sciences literature with potential relevance to health sciences librarianship; to discuss the limited number of RCTs within health sciences librarianship. narrative review supported to a limited extent with PubMed and Library Literature database searches consistent with specific search parameters. In addition, more systematic methods, including handsearching of specific journals, to identify health sciences librarianship RCTs. While many RCTs within the health sciences follow more conventional patterns, some RCTs assume certain unique features. Selected examples illustrate the adaptations of this experimental design to answering questions of possible relevance to health sciences librarians. The author offers several strategies for controlling bias in library and informatics applications of the RCT and acknowledges the potential of the electronic era in providing many opportunities to utilize the blinding aspects of RCTs. RCTs within health sciences librarianship inhabit a limited number of subject domains such as education. This limited scope offers both advantages and disadvantages for making Evidence-Based Librarianship (EBL) a reality. The RCT design offers the potential to answer far more EBL questions than have been addressed by the design to date. Librarians need only extend their horizons through use of the versatile RCT design into new subject domains to facilitate making EBL a reality.

Recent applications of the transonic wing analysis computer code, TWING

NASA Technical Reports Server (NTRS)

Subramanian, N. R.; Holst, T. L.; Thomas, S. D.

1982-01-01

An evaluation of the transonic-wing-analysis computer code TWING is given. TWING utilizes a fully implicit approximate factorization iteration scheme to solve the full potential equation in conservative form. A numerical elliptic-solver grid-generation scheme is used to generate the required finite-difference mesh. Several wing configurations were analyzed, and the limits of applicability of this code was evaluated. Comparisons of computed results were made with available experimental data. Results indicate that the code is robust, accurate (when significant viscous effects are not present), and efficient. TWING generally produces solutions an order of magnitude faster than other conservative full potential codes using successive-line overrelaxation. The present method is applicable to a wide range of isolated wing configurations including high-aspect-ratio transport wings and low-aspect-ratio, high-sweep, fighter configurations.

Membrane separation for non-aqueous solution

NASA Astrophysics Data System (ADS)

Widodo, S.; Khoiruddin; Ariono, D.; Subagjo; Wenten, I. G.

2018-01-01

Membrane technology has been widely used in a number of applications competing with conventional technologies in various ways. Despite the enormous applications, they are mainly used for the aqueous system. The use of membrane-based processes in a non-aqueous system is an emerging area. This is because developed membranes are still limited in separations involving aqueous solution which show several drawbacks when implemented in a non-aqueous system. The purpose of this paper is to provide a review of the current application of membrane processes in non-aqueous solutions, such as mineral oil treatment, vegetable oil processing, and organic solvent recovery. Developments of advanced membrane materials for the non-aqueous solutions such as super-hydrophobic and organic solvent resistant membranes are reviewed. In addition, challenges and future outlook of membrane separation for the non-aqueous solution are discussed.

Introduction to focus issue: Synchronization in large networks and continuous media—data, models, and supermodels

NASA Astrophysics Data System (ADS)

Duane, Gregory S.; Grabow, Carsten; Selten, Frank; Ghil, Michael

2017-12-01

The synchronization of loosely coupled chaotic systems has increasingly found applications to large networks of differential equations and to models of continuous media. These applications are at the core of the present Focus Issue. Synchronization between a system and its model, based on limited observations, gives a new perspective on data assimilation. Synchronization among different models of the same system defines a supermodel that can achieve partial consensus among models that otherwise disagree in several respects. Finally, novel methods of time series analysis permit a better description of synchronization in a system that is only observed partially and for a relatively short time. This Focus Issue discusses synchronization in extended systems or in components thereof, with particular attention to data assimilation, supermodeling, and their applications to various areas, from climate modeling to macroeconomics.

Introduction to focus issue: Synchronization in large networks and continuous media-data, models, and supermodels.

PubMed

Duane, Gregory S; Grabow, Carsten; Selten, Frank; Ghil, Michael

2017-12-01

The synchronization of loosely coupled chaotic systems has increasingly found applications to large networks of differential equations and to models of continuous media. These applications are at the core of the present Focus Issue. Synchronization between a system and its model, based on limited observations, gives a new perspective on data assimilation. Synchronization among different models of the same system defines a supermodel that can achieve partial consensus among models that otherwise disagree in several respects. Finally, novel methods of time series analysis permit a better description of synchronization in a system that is only observed partially and for a relatively short time. This Focus Issue discusses synchronization in extended systems or in components thereof, with particular attention to data assimilation, supermodeling, and their applications to various areas, from climate modeling to macroeconomics.

Applications of UAVs in row-crop agriculture: advantages and limitations

NASA Astrophysics Data System (ADS)

Basso, B.; Putnam, G.; Price, R.; Zhang, J.

2016-12-01

The application of Unmanned Aerial Vehicles (UAV) to monitor agricultural fields has increased over the last few years due to advances in the technology, sensors, post-processing software for image analysis, along with more favorable regulations that allowed UAVs to be flown for commercial use. UAV have several capabilities depending on the type of sensors that are mounted onboard. The most widely used application remains crop scouting to identify areas within fields where the crops underperform for various reasons (nutritional status and water stress, presence of weeds, poor stands etc). In this talk, we present the preliminary results of UAVs field based research to better understand spatial and temporal variability of crop yield. Their advantage in providing timely information is critical, but adaptive management requires a system approach to account for the interactions occurring between genetics, environment and management.

Advancement Of Tritium Powered Betavoltaic Battery Systems

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

Staack, G.; Gaillard, J.; Hitchcock, D.

2015-10-14

Due to their decades-long service life and reliable power output under extreme conditions, betavoltaic batteries offer distinct advantages over traditional chemical batteries, especially in applications where frequent battery replacement is hazardous, or cost prohibitive. Although many beta emitting isotopes exist, tritium is considered ideal in betavoltaic applications for several reasons: 1) it is a “pure” beta emitter, 2) the beta is not energetic enough to damage the semiconductor, 3) it has a moderately long half-life, and 4) it is readily available. Unfortunately, the widespread application of tritium powered betavoltaics is limited, in part, by their low power output. This researchmore » targets improving the power output of betavoltaics by increasing the flux of beta particles to the energy conversion device (the p-n junction) through the use of low Z nanostructured tritium trapping materials.« less

Computation of the phase response curve: a direct numerical approach.

PubMed

Govaerts, W; Sautois, B

2006-04-01

Neurons are often modeled by dynamical systems--parameterized systems of differential equations. A typical behavioral pattern of neurons is periodic spiking; this corresponds to the presence of stable limit cycles in the dynamical systems model. The phase resetting and phase response curves (PRCs) describe the reaction of the spiking neuron to an input pulse at each point of the cycle. We develop a new method for computing these curves as a by-product of the solution of the boundary value problem for the stable limit cycle. The method is mathematically equivalent to the adjoint method, but our implementation is computationally much faster and more robust than any existing method. In fact, it can compute PRCs even where the limit cycle can hardly be found by time integration, for example, because it is close to another stable limit cycle. In addition, we obtain the discretized phase response curve in a form that is ideally suited for most applications. We present several examples and provide the implementation in a freely available Matlab code.

Active Videogaming for Individuals with Severe Movement Disorders: Results from a Community Study.

PubMed

Chung, Peter J; Vanderbilt, Douglas L; Schrager, Sheree M; Nguyen, Eugene; Fowler, Eileen

2015-06-01

Active videogaming (AVG) has potential to provide positive health outcomes for individuals with cerebral palsy (CP), but their use for individuals with severe motor impairments is limited. Our objective was to evaluate the accessibility and enjoyment of videogames using the Kinect™ (Microsoft, Redmond, WA) with the Flexible Action and Articulated Skeleton Toolkit (FAAST) system (University of Southern California Institute for Creative Technologies, Los Angeles, CA) for individuals with severely limiting CP. A videogaming system was installed in a community center serving adults with CP, and a staff member was instructed in its use. Participants completed a baseline survey assessing demographics, mobility, and prior videogame experience; they then used the FAAST system with Kinect and completed a 5-point Likert survey to assess their experience. Descriptive statistics assessed overall enjoyment of the system, and Mann-Whitney U tests were conducted to determine whether responses differed by demographic factors, mobility, or prior videogame experience. Twenty-two subjects were recruited. The enjoyment scale demonstrated high internal consistency (Cronbach's alpha=0.88). The mean total enjoyment score was 4.24 out of 5. Median scores did not significantly differ by ethnicity, gender, CP severity, or previous videogame exposure. The FAAST with Kinect is a low-cost system that engages individuals with severe movement disorders across a wide range of physical ability and videogame experience. Further research should be conducted on in-home use, therapeutic applications, and potential benefits for socialization.

Optical aperture synthesis: limitations and interest for the earth observation

NASA Astrophysics Data System (ADS)

Brouard, Laurent; Safa, Frederic; Crombez, Vincent; Laubier, David

2017-11-01

For very large telescope diameters, typically above 4 meters, monolithic telescopes can hardly be envisaged for space applications. Optical aperture synthesis can be envisaged in the future for improving the image resolution from high altitude orbits by co-phasing several individual telescopes of smaller size and reconstituting an aperture of large surface. The telescopes can be deployed on a single spacecraft or distributed on several spacecrafts in free flying formation. Several future projects are based on optical aperture synthesis for science or earth observation. This paper specifically discusses the limitations and interest of aperture synthesis technique for Earth observation from high altitude orbits, in particular geostationary orbit. Classical Fizeau and Michelson configurations are recalled, and system design aspects are investigated: synthesis of the Modulation Transfer Function (MTF), integration time and imaging procedure are first discussed then co-phasing strategies and instrument metrology are developed. The discussion is supported by specific designs made at EADS Astrium. As example, a telescope design is presented with a surface of only 6.6 m2 for the primary mirror for an external diameter of 10.6 m allowing a theoretical resolution of 1.2 m from geostationary orbit with a surface lower than 10% of the overall surface. The impact is that the integration time is increasing leading to stringent satellite attitude requirements. Image simulation results are presented. The practical implementation of the concept is evaluated in terms of system impacts in particular spacecraft attitude control, spacecraft operations and imaging capability limitations.

Accelerating Progress in Eating Disorders Prevention: A Call for Policy Translation Research and Training.

PubMed

Austin, S Bryn

2016-01-01

The public health burden of eating disorders is well documented, and over the past several decades, researchers have made important advances in the prevention of eating disorders and related problems with body image. Despite these advances, however, several critical limitations to the approaches developed to date leave the field far from achieving the large-scale impact that is needed. This commentary provides a brief review of what achievements in prevention have been made and identifies the gaps that limit the potential for greater impact on population health. A plan is then offered with specific action steps to accelerate progress in high-impact prevention, most compellingly by promoting a shift in priorities to policy translation research and training for scholars through the adoption of a triggers-to-action framework. Finally, the commentary provides an example of the application of the triggers-to-action framework as practiced at the Strategic Training Initiative for the Prevention of Eating Disorders, a program based at the Harvard T. H. Chan School of Public Health and Boston Children's Hospital. Much has been achieved in the nearly 30 years of research carried out for the prevention of eating disorders and body image problems, but several critical limitations undermine the field's potential for meaningful impact. Through a shift in the field's priorities to policy translation research and training with an emphasis on macro-environmental influences, the pace of progress in prevention can be accelerated and the potential for large-scale impact substantially improved.

Improved methods in neural network-based adaptive output feedback control, with applications to flight control

NASA Astrophysics Data System (ADS)

Kim, Nakwan

Utilizing the universal approximation property of neural networks, we develop several novel approaches to neural network-based adaptive output feedback control of nonlinear systems, and illustrate these approaches for several flight control applications. In particular, we address the problem of non-affine systems and eliminate the fixed point assumption present in earlier work. All of the stability proofs are carried out in a form that eliminates an algebraic loop in the neural network implementation. An approximate input/output feedback linearizing controller is augmented with a neural network using input/output sequences of the uncertain system. These approaches permit adaptation to both parametric uncertainty and unmodeled dynamics. All physical systems also have control position and rate limits, which may either deteriorate performance or cause instability for a sufficiently high control bandwidth. Here we apply a method for protecting an adaptive process from the effects of input saturation and time delays, known as "pseudo control hedging". This method was originally developed for the state feedback case, and we provide a stability analysis that extends its domain of applicability to the case of output feedback. The approach is illustrated by the design of a pitch-attitude flight control system for a linearized model of an R-50 experimental helicopter, and by the design of a pitch-rate control system for a 58-state model of a flexible aircraft consisting of rigid body dynamics coupled with actuator and flexible modes. A new approach to augmentation of an existing linear controller is introduced. It is especially useful when there is limited information concerning the plant model, and the existing controller. The approach is applied to the design of an adaptive autopilot for a guided munition. Design of a neural network adaptive control that ensures asymptotically stable tracking performance is also addressed.

ADAM: An Accident Diagnostic,Analysis and Management System - Applications to Severe Accident Simulation and Management

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

Zavisca, M.J.; Khatib-Rahbar, M.; Esmaili, H.

2002-07-01

The Accident Diagnostic, Analysis and Management (ADAM) computer code has been developed as a tool for on-line applications to accident diagnostics, simulation, management and training. ADAM's severe accident simulation capabilities incorporate a balance of mechanistic, phenomenologically based models with simple parametric approaches for elements including (but not limited to) thermal hydraulics; heat transfer; fuel heatup, meltdown, and relocation; fission product release and transport; combustible gas generation and combustion; and core-concrete interaction. The overall model is defined by a relatively coarse spatial nodalization of the reactor coolant and containment systems and is advanced explicitly in time. The result is to enablemore » much faster than real time (i.e., 100 to 1000 times faster than real time on a personal computer) applications to on-line investigations and/or accident management training. Other features of the simulation module include provision for activation of water injection, including the Engineered Safety Features, as well as other mechanisms for the assessment of accident management and recovery strategies and the evaluation of PSA success criteria. The accident diagnostics module of ADAM uses on-line access to selected plant parameters (as measured by plant sensors) to compute the thermodynamic state of the plant, and to predict various margins to safety (e.g., times to pressure vessel saturation and steam generator dryout). Rule-based logic is employed to classify the measured data as belonging to one of a number of likely scenarios based on symptoms, and a number of 'alarms' are generated to signal the state of the reactor and containment. This paper will address the features and limitations of ADAM with particular focus on accident simulation and management. (authors)« less

Using neutral, selected, and hitchhiker loci to assess connectivity of marine populations in the genomic era

PubMed Central

Gagnaire, Pierre-Alexandre; Broquet, Thomas; Aurelle, Didier; Viard, Frédérique; Souissi, Ahmed; Bonhomme, François; Arnaud-Haond, Sophie; Bierne, Nicolas

2015-01-01

Estimating the rate of exchange of individuals among populations is a central concern to evolutionary ecology and its applications to conservation and management. For instance, the efficiency of protected areas in sustaining locally endangered populations and ecosystems depends on reserve network connectivity. The population genetics theory offers a powerful framework for estimating dispersal distances and migration rates from molecular data. In the marine realm, however, decades of molecular studies have met limited success in inferring genetic connectivity, due to the frequent lack of spatial genetic structure in species exhibiting high fecundity and dispersal capabilities. This is especially true within biogeographic regions bounded by well-known hotspots of genetic differentiation. Here, we provide an overview of the current methods for estimating genetic connectivity using molecular markers and propose several directions for improving existing approaches using large population genomic datasets. We highlight several issues that limit the effectiveness of methods based on neutral markers when there is virtually no genetic differentiation among samples. We then focus on alternative methods based on markers influenced by selection. Although some of these methodologies are still underexplored, our aim was to stimulate new research to test how broadly they are applicable to nonmodel marine species. We argue that the increased ability to apply the concepts of cline analyses will improve dispersal inferences across physical and ecological barriers that reduce connectivity locally. We finally present how neutral markers hitchhiking with selected loci can also provide information about connectivity patterns within apparently well-mixed biogeographic regions. We contend that one of the most promising applications of population genomics is the use of outlier loci to delineate relevant conservation units and related eco-geographic features across which connectivity can be measured. PMID:26366195

Limitation of life-sustaining treatment in patients with prolonged admission to the ICU. Current situation in Spain as seen from the EPIPUSE Study.

PubMed

Hernández-Tejedor, A; Martín Delgado, M C; Cabré Pericas, L; Algora Weber, A

2015-10-01

Limitation of life-sustaining treatment (LLST) is a recommended practice in certain circumstances. Limitation practices are varied, and their application differs from one center to another. The present study evaluates the current situation of LLST practices in patients with prolonged admission to the ICU who suffer worsening of their condition. A prospective, observational cohort study was carried out. Seventy-five Spanish ICUs. A total of 589 patients suffering 777 complications or adverse events with organ function impairment after day 7 of admission, during a three-month recruitment period. The timing of limitation, the subject proposing LLST, the degree of agreement within the team, the influence of LLST upon the doctor-patient-family relationship, and the way in which LLST is implemented. LLST was proposed in 34.3% of the patients presenting prolonged admission to the ICU with severe complications. The incidence was higher in patients with moderate to severe lung disease, cancer, immunosuppressive treatment or dependence for basic activities of daily living. LLST was finally implemented in 97% of the cases in which it was proposed. The decision within the medical team was unanimous in 87.9% of the cases. The doctor-patient-family relationship usually does not change or even improves in this situation. LLST in ICUs is usually carried out under unanimous decision of the medical team, is performed more frequently in patients with severe comorbidity, and usually does not have a negative impact upon the relationship with the patients and their families. Copyright © 2013 Elsevier España, S.L.U. and SEMICYUC. All rights reserved.

Challenges of Obtaining Evidence-Based Information Regarding Medications and Male Fertility.

PubMed

Drobnis, Erma Z; Nangia, Ajay K

2017-01-01

In the clinic, the existing literature is insufficient to counsel our infertile men on medication use. Most studies have flaws that limit their application to evidence-based practice. In this chapter, we discuss the limitations of the current literature and the challenges to designing more useful studies. Among the most important weaknesses of existing studies is lack of power; that is, too few men are included to draw conclusions about the existence and size of medication effects. Adequate power is particularly important when confirming an absence of medication effect. Bias is also a problem in most studies. Early studies were rarely randomized, placebo-controlled, or blinded; a common example is patients receiving different medication regimes based on the severity of their symptoms-making it impossible to attribute differences between treated and untreated men to the medications. Additional bias is introduced by failing to include other factors that influence the outcome in the experimental design. A uniform population amenable to randomization and placebo-control are experimental species, and useful information has been gained from these models. However, application to humans is limited by differences from other species in route of drug administration, absorption of the drug, concentration in the male genital tract tissues, and genital tract physiology. To a lesser degree, there is variation among individual men in their response to drugs. In addition, drugs in the same class may have different effects, limiting the applicability of data across drugs of a single class. Complicating matters further, a toxic medication may seem to improve fertility endpoints by improving a disease condition that diminishes fertility. Finally, drug interactions have not been studied, and actual fertility data (pregnancy/fecundity) in humans are rare. A healthy dose of skepticism is warranted when evaluating studies of medications and male reproductive health.

Qualitative biomechanical principles for application in coaching.

PubMed

Knudson, Duane

2007-01-01

Many aspects of human movements in sport can be readily understood by Newtonian rigid-body mechanics. Many of these laws and biomechanical principles, however, are counterintuitive to a lot of people. There are also several problems in the application of biomechanics to sports, so the application of biomechanics in the qualitative analysis of sport skills by many coaches has been limited. Biomechanics scholars have long been interested in developing principles that facilitate the qualitative application of biomechanics to improve movement performance and reduce the risk of injury. This paper summarizes the major North American efforts to establish a set of general biomechanical principles of movement, and illustrates how principles can be used to improve the application of biomechanics in the qualitative analysis of sport technique. A coach helping a player with a tennis serve is presented as an example. The standardization of terminology for biomechanical principles is proposed as an important first step in improving the application ofbiomechanics in sport. There is also a need for international cooperation and research on the effectiveness of applying biomechanical principles in the coaching of sport techniques.

Application of Mixed Effects Limits of Agreement in the Presence of Multiple Sources of Variability: Exemplar from the Comparison of Several Devices to Measure Respiratory Rate in COPD Patients

PubMed Central

Weir, Christopher J.; Rubio, Noah; Rabinovich, Roberto; Pinnock, Hilary; Hanley, Janet; McCloughan, Lucy; Drost, Ellen M.; Mantoani, Leandro C.; MacNee, William; McKinstry, Brian

2016-01-01

Introduction The Bland-Altman limits of agreement method is widely used to assess how well the measurements produced by two raters, devices or systems agree with each other. However, mixed effects versions of the method which take into account multiple sources of variability are less well described in the literature. We address the practical challenges of applying mixed effects limits of agreement to the comparison of several devices to measure respiratory rate in patients with chronic obstructive pulmonary disease (COPD). Methods Respiratory rate was measured in 21 people with a range of severity of COPD. Participants were asked to perform eleven different activities representative of daily life during a laboratory-based standardised protocol of 57 minutes. A mixed effects limits of agreement method was used to assess the agreement of five commercially available monitors (Camera, Photoplethysmography (PPG), Impedance, Accelerometer, and Chest-band) with the current gold standard device for measuring respiratory rate. Results Results produced using mixed effects limits of agreement were compared to results from a fixed effects method based on analysis of variance (ANOVA) and were found to be similar. The Accelerometer and Chest-band devices produced the narrowest limits of agreement (-8.63 to 4.27 and -9.99 to 6.80 respectively) with mean bias -2.18 and -1.60 breaths per minute. These devices also had the lowest within-participant and overall standard deviations (3.23 and 3.29 for Accelerometer and 4.17 and 4.28 for Chest-band respectively). Conclusions The mixed effects limits of agreement analysis enabled us to answer the question of which devices showed the strongest agreement with the gold standard device with respect to measuring respiratory rates. In particular, the estimated within-participant and overall standard deviations of the differences, which are easily obtainable from the mixed effects model results, gave a clear indication that the Accelerometer and Chest-band devices performed best. PMID:27973556

Great talent, excellent voices-no problem for pubertal girls?

PubMed

Decoster, Wivine; Ghesquiere, Sofie; Van Steenberge, Sebastiaan

2008-01-01

This research on 17 girls (aged 9;9 y to 16;11 y) singing in an established choir was focused on two issues: 1) the variety in physical and vocal development using Gackle's model, and 2) the matching of vocal demands and abilities. Developmental and acoustical data on the speaking and singing voice revealed considerable variation between individual girl singers. The model was greatly applicable. However, all girls had a greater total singing range, mainly in favour of the lower tones, and 11 girls used a lower speaking fundamental frequency. A third of the girls met the vocal and developmental features of their stage at a younger age. Next the lower limit of the frequency range of all girls was several semitones below the lowest notes of the pieces being worked on at the time of the experiment. However the upper limit of the pieces coincided with or exceeded their upper frequency limit.

Radio frequency identification (RFID) in health care: privacy and security concerns limiting adoption.

PubMed

Rosenbaum, Benjamin P

2014-03-01

Radio frequency identification (RFID) technology has been implemented in a wide variety of industries. Health care is no exception. This article explores implementations and limitations of RFID in several health care domains: authentication, medication safety, patient tracking, and blood transfusion medicine. Each domain has seen increasing utilization of unique applications of RFID technology. Given the importance of protecting patient and data privacy, potential privacy and security concerns in each domain are discussed. Such concerns, some of which are inherent to existing RFID hardware and software technology, may limit ubiquitous adoption. In addition, an apparent lack of security standards within the RFID domain and specifically health care may also hinder the growth and utility of RFID within health care for the foreseeable future. Safeguarding the privacy of patient data may be the most important obstacle to overcome to allow the health care industry to take advantage of the numerous benefits RFID technology affords.

Achievable Performance and Effective Interrogator Design for SAW RFID Sensor Tags

NASA Technical Reports Server (NTRS)

Barton, Richard J.

2011-01-01

For many NASA missions, remote sensing is a critical application that supports activities such as environmental monitoring, planetary science, structural shape and health monitoring, non-destructive evaluation, etc. The utility of the remote sensing devices themselves is greatly increased if they are passive that is, they do not require any on-board power supply such as batteries and if they can be identified uniquely during the sensor interrogation process. Additional passive sensor characteristics that enable greater utilization in space applications are small size and weight, long read ranges with low interrogator power, ruggedness, and operability in extreme environments (vacuum, extreme high/low temperature, high radiation, etc.) In this paper, we consider one very promising passive sensor technology, called surface acoustic wave (SAW) radio-frequency identification (RFID), that satisfies all of these criteria. Although SAW RFID tags have great potential for use in numerous space-based remote sensing applications, the limited collision resolution capability of current generation tags limits the performance in a cluttered sensing environment. That is, as more SAW-based sensors are added to the environment, numerous tag responses are superimposed at the receiver and decoding all or even a subset of the telemetry becomes increasingly difficult. Background clutter generated by reflectors other than the sensors themselves is also a problem, as is multipath interference and signal distortion, but the limiting factor in many remote sensing applications can be expected to be tag mutual interference. This problem may be greatly mitigated by proper design of the SAW tag waveform, but that remains an open research problem, and in the meantime, several other related questions remain to be answered including: What are the fundamental relationships between tag parameters such as bit-rate, time-bandwidth-product, SNR, and achievable collision resolution? What are the differences in optimal or near-optimal interrogator designs between noise-limited environments and interference-limited environments? What are the performance characteristics of different interrogator designs in term of parameters such as transmitter power level, range, and number of interfering tags? In this paper, we present the results of a research effort aimed at providing at least partial answers to all of these questions.

Nanonization strategies for poorly water-soluble drugs.

PubMed

Chen, Huabing; Khemtong, Chalermchai; Yang, Xiangliang; Chang, Xueling; Gao, Jinming

2011-04-01

Poor water solubility for many drugs and drug candidates remains a major obstacle to their development and clinical application. Conventional formulations to improve solubility suffer from low bioavailability and poor pharmacokinetics, with some carriers rendering systemic toxicities (e.g. Cremophor(®) EL). In this review, several major nanonization techniques that seek to overcome these limitations for drug solubilization are presented. Strategies including drug nanocrystals, nanoemulsions and polymeric micelles are reviewed. Finally, perspectives on existing challenges and future opportunities are highlighted. Published by Elsevier Ltd.

Method and apparatus for optoacoustic spectroscopy

DOEpatents

Amer, Nabil M.

1979-01-01

A method and apparatus that significantly increases the sensitivity and flexibility of laser optoacoustic spectroscopy, with reduced size. With the method, it no longer is necessary to limit the use of laser optoacoustic spectroscopy to species whose absorption must match available laser radiation. Instead, "doping" with a relatively small amount of an optically absorbing gas yields optoacoustic signatures of nonabsorbing materials (gases, liquids, solids, and aerosols), thus significantly increasing the sensitivity and flexibility of optoacoustic spectroscopy. Several applications of this method are demonstated and/or suggested.

Reviewing sulfidation corrosion—Yesterday and today

NASA Astrophysics Data System (ADS)

Bornstein, Norman S.

1996-11-01

At one time, sulfidation corrosion threatened to severely limit the use of gas turbines in marine applications, markedly reduce the life of industrial gas turbines, and affect the performance of aircraft engines. Today, gas turbine engines drive U.S. naval ships, produce electricity, and power aircraft. However, the problem of sulfidation corrosion has not disappeared. The rapid rate of degradation of airfoil materials in the presence of condensed sulfates is still a concern for gas turbine engines that operate in industrial and marine environments.

Clinical applications of angiocardiography

NASA Technical Reports Server (NTRS)

Dodge, H. T.; Sandler, H.

1974-01-01

Several tables are presented giving left ventricular (LV) data for normal patients and patients with heart disease of varied etiologies, pointing out the salient features. Graphs showing LV pressure-volume relationships (compliance) are presented and discussed. The method developed by Rackley et al. (1964) for determining left ventricular mass in man is described, and limitations to the method are discussed. Some clinical methods for determining LV oxygen consumption are briefly described, and the relation of various abnormalities of ventricular performance to coronary artery disease and ischemic heart disease is characterized.

A Clock Fingerprints-Based Approach for Wireless Transmitter Identification

NASA Astrophysics Data System (ADS)

Zhao, Caidan; Xie, Liang; Huang, Lianfen; Yao, Yan

Cognitive radio (CR) was proposed as one of the promising solutions for low spectrum utilization. However, security problems such as the primary user emulation (PUE) attack severely limit its applications. In this paper, we propose a clock fingerprints-based authentication approach to prevent PUE attacks in CR networks with the help of curve fitting and classifier. An experimental setup was constructed using the WLAN cards and software radio devices, and the corresponding results show that satisfied identification can be achieved for wireless transmitters.

Optical coherent tomography and fluorescent microscopy for the study of meningeal lymphatic systems

NASA Astrophysics Data System (ADS)

Semyachkina-Glushkovskaya, O.; Abdurashitov, A.; Namykin, A.; Fedosov, I.; Pavlov, A.; Karavaev, A.; Sindeeva, O.; Shirokov, A.; Ulanova, M.; Shushunova, N.; Khorovodov, A.; Agranovich, I.; Bodrova, A.; Sagatova, M.; Shareef, Ali Esmat; Saranceva, E.; Dvoryatkina, M.; Tuchin, V.

2018-04-01

The development of novel technologies for the imaging of meningeal lymphatic vessels is one of the amazing trends of biophotonics thanks to discovery of brain lymphatics over several years ago. However, there is the limited technologies exist for the study of lymphatics in vivo because lymphatic vessels are transparent with a low speed flow of lymph. Here we demonstrate the successful application of fluorescent microscopy for the imaging of lymphatic system in the mouse brain in vivo.

Multi-fidelity stochastic collocation method for computation of statistical moments

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

Zhu, Xueyu, E-mail: xueyu-zhu@uiowa.edu; Linebarger, Erin M., E-mail: aerinline@sci.utah.edu; Xiu, Dongbin, E-mail: xiu.16@osu.edu

We present an efficient numerical algorithm to approximate the statistical moments of stochastic problems, in the presence of models with different fidelities. The method extends the multi-fidelity approximation method developed in . By combining the efficiency of low-fidelity models and the accuracy of high-fidelity models, our method exhibits fast convergence with a limited number of high-fidelity simulations. We establish an error bound of the method and present several numerical examples to demonstrate the efficiency and applicability of the multi-fidelity algorithm.

Analysis methods for Kevlar shield response to rotor fragments

NASA Technical Reports Server (NTRS)

Gerstle, J. H.

1977-01-01

Several empirical and analytical approaches to rotor burst shield sizing are compared and principal differences in metal and fabric dynamic behavior are discussed. The application of transient structural response computer programs to predict Kevlar containment limits is described. For preliminary shield sizing, present analytical methods are useful if insufficient test data for empirical modeling are available. To provide other information useful for engineering design, analytical methods require further developments in material characterization, failure criteria, loads definition, and post-impact fragment trajectory prediction.

Neurosurgery: Functional regeneration after laser axotomy

NASA Astrophysics Data System (ADS)

Yanik, Mehmet Fatih; Cinar, Hulusi; Cinar, Hediye Nese; Chisholm, Andrew D.; Jin, Yishi; Ben-Yakar, Adela

2004-12-01

Understanding how nerves regenerate is an important step towards developing treatments for human neurological disease, but investigation has so far been limited to complex organisms (mouse and zebrafish) in the absence of precision techniques for severing axons (axotomy). Here we use femtosecond laser surgery for axotomy in the roundworm Caenorhabditis elegans and show that these axons functionally regenerate after the operation. Application of this precise surgical technique should enable nerve regeneration to be studied in vivo in its most evolutionarily simple form.

Charging and heat collection by a positively charged dust grain in a plasma.

PubMed

Delzanno, Gian Luca; Tang, Xian-Zhu

2014-07-18

Dust particulates immersed in a quasineutral plasma can emit electrons in several important applications. Once electron emission becomes strong enough, the dust enters the positively charged regime where the conventional orbital-motion-limited (OML) theory can break down due to potential-well effects on trapped electrons. A minimal modification of the trapped-passing boundary approximation in the so-called OML(+) approach is shown to accurately predict the dust charge and heat collection flux for a wide range of dust size and temperature.

Optical fiber technology for space: challenges of development and qualification

NASA Astrophysics Data System (ADS)

Goepel, Michael

2017-11-01

Using fiber optical components and assemblies for space flight applications brings several challenges for the design and the qualification process. Good knowledge of the system and environmental requirements is needed to derive design decisions and select suitable components for the fiber optical subsystem. Furthermore, the manufacturing process and integration limitations are providing additional constraints, which have to be considered at the beginning of the design phase. Besides Commercial off the shelf (COTS) components, custom made parts are often necessary.

Computer programs: Operational and mathematical, a compilation

NASA Technical Reports Server (NTRS)

1973-01-01

Several computer programs which are available through the NASA Technology Utilization Program are outlined. Presented are: (1) Computer operational programs which can be applied to resolve procedural problems swiftly and accurately. (2) Mathematical applications for the resolution of problems encountered in numerous industries. Although the functions which these programs perform are not new and similar programs are available in many large computer center libraries, this collection may be of use to centers with limited systems libraries and for instructional purposes for new computer operators.

Accelerated stability assay (ASA) for colloidal systems.

PubMed

Chong, Josephine Y T; Mulet, Xavier; Boyd, Ben J; Drummond, Calum J

2014-05-12

Assessment of the stability of colloidal systems, in particular lyotropic liquid crystalline dispersions, such as cubosomes and hexosomes, is typically performed qualitatively or with limited throughput on specialized instruments. Here, an accelerated stability assay for colloidal particles has been developed in 384-well plates with standard laboratory equipment. These protocols enable quantitative assessments of colloidal stability. To demonstrate the applicability of the assay, several steric stabilizers for cubic phase nanostructured particles (cubosomes) have been compared to the current "gold standard" Pluronic F127.

Evaluation of quasi-square wave inverter as a power source for induction motors

NASA Technical Reports Server (NTRS)

Guynes, B. V.; Haggard, R. L.; Lanier, J. R., Jr.

1977-01-01

The relative merits of quasi-square wave inverter-motor technology versus a sine wave inverter-motor system were investigated. The empirical results of several tests on various sizes of wye-wound induction motors are presented with mathematical analysis to support the conclusions of the study. It was concluded that, within the limitations presented, the quasi-square wave inverter-motor system is superior to the more complex sine wave system for most induction motor applications in space.

Developing Effective Continuous On-Line Monitoring Technologies to Manage Service Degradation of Nuclear Power Plants

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

Meyer, Ryan M.; Ramuhalli, Pradeep; Bond, Leonard J.

2011-09-30

Recently, there has been increased interest in using prognostics (i.e, remaining useful life (RUL) prediction) for managing and mitigating aging effects in service-degraded passive nuclear power reactor components. A vital part of this philosophy is the development of tools for detecting and monitoring service-induced degradation. Experience with in-service degradation has shown that rapidly-growing cracks, including several varieties of stress corrosion cracks (SCCs), can grow through a pipe in less than one fuel outage cycle after they initiate. Periodic inspection has limited effectiveness at detecting and managing such degradation requiring a more versatile monitoring philosophy. Acoustic emission testing (AET) and guidedmore » wave ultrasonic testing (GUT) are related technologies with potential for on-line monitoring applications. However, harsh operating conditions within NPPs inhibit the widespread implementation of both technologies. For AET, another hurdle is the attenuation of passive degradation signals as they travel though large components, relegating AET to targeted applications. GUT is further hindered by the complexity of GUT signatures limiting its application to the inspection of simple components. The development of sensors that are robust and inexpensive is key to expanding the use of AET and GUT for degradation monitoring in NPPs and improving overall effectiveness. Meanwhile, the effectiveness of AET and GUT in NPPs can be enhanced through thoughtful application of tandem AET-GUT techniques.« less

Studying Radiation Damage in Structural Materials by Using Ion Accelerators

NASA Astrophysics Data System (ADS)

Hosemann, Peter

2011-02-01

Radiation damage in structural materials is of major concern and a limiting factor for a wide range of engineering and scientific applications, including nuclear power production, medical applications, or components for scientific radiation sources. The usefulness of these applications is largely limited by the damage a material can sustain in the extreme environments of radiation, temperature, stress, and fatigue, over long periods of time. Although a wide range of materials has been extensively studied in nuclear reactors and neutron spallation sources since the beginning of the nuclear age, ion beam irradiations using particle accelerators are a more cost-effective alternative to study radiation damage in materials in a rather short period of time, allowing researchers to gain fundamental insights into the damage processes and to estimate the property changes due to irradiation. However, the comparison of results gained from ion beam irradiation, large-scale neutron irradiation, and a variety of experimental setups is not straightforward, and several effects have to be taken into account. It is the intention of this article to introduce the reader to the basic phenomena taking place and to point out the differences between classic reactor irradiations and ion irradiations. It will also provide an assessment of how accelerator-based ion beam irradiation is used today to gain insight into the damage in structural materials for large-scale engineering applications.

Application of contrast media in post-mortem imaging (CT and MRI).

PubMed

Grabherr, Silke; Grimm, Jochen; Baumann, Pia; Mangin, Patrice

2015-09-01

The application of contrast media in post-mortem radiology differs from clinical approaches in living patients. Post-mortem changes in the vascular system and the absence of blood flow lead to specific problems that have to be considered for the performance of post-mortem angiography. In addition, interpreting the images is challenging due to technique-related and post-mortem artefacts that have to be known and that are specific for each applied technique. Although the idea of injecting contrast media is old, classic methods are not simply transferable to modern radiological techniques in forensic medicine, as they are mostly dedicated to single-organ studies or applicable only shortly after death. With the introduction of modern imaging techniques, such as post-mortem computed tomography (PMCT) and post-mortem magnetic resonance (PMMR), to forensic death investigations, intensive research started to explore their advantages and limitations compared to conventional autopsy. PMCT has already become a routine investigation in several centres, and different techniques have been developed to better visualise the vascular system and organ parenchyma in PMCT. In contrast, the use of PMMR is still limited due to practical issues, and research is now starting in the field of PMMR angiography. This article gives an overview of the problems in post-mortem contrast media application, the various classic and modern techniques, and the issues to consider by using different media.

Lithium-Metal Infused Trenches: Progress toward a Divertor Solution

NASA Astrophysics Data System (ADS)

Ruzic, D. N.; Fiflis, P.; Christenson, M.; Szott, M.; Xu, W.; Jung, S.; Morgan, T. W.; Kalathiparambil, K.

2014-10-01

The application of liquid metal, especially liquid lithium, as a plasma facing component (PFC) has the capacity to offer a strong alternative to solid PFCs by reducing damage concerns and enhancing plasma performance. The Liquid-Metal Infused Trenches (LiMIT) concept is a liquid metal divertor alternative which employs thermoelectric current from either plasma or external heating in tandem with the toroidal field to self-propel liquid lithium through a series of trenches. LiMIT has been tested in several devices, namely HT-7, the UIUC SLiDE and TELS facilities and Magnum PSI at heat fluxes of up to 3 MW/m-2. Results of these experiments, including velocity and temperature measurements, power handling considerations, and preliminary vapor shielding results will be discussed, focusing on the 117 shots performed at Magnum scanning magnetic fields and heat fluxes up to ~ 0.3 T and 3 MW/m-2. Concerns over tritium retention and MHD droplet ejection will additionally be addressed. LiMIT has also been proposed to function as a limiter on the EAST moveable limiter arm and tests have been performed with a prototype module inclined at various angles.

Automatic rectum limit detection by anatomical markers correlation.

PubMed

Namías, R; D'Amato, J P; del Fresno, M; Vénere, M

2014-06-01

Several diseases take place at the end of the digestive system. Many of them can be diagnosed by means of different medical imaging modalities together with computer aided detection (CAD) systems. These CAD systems mainly focus on the complete segmentation of the digestive tube. However, the detection of limits between different sections could provide important information to these systems. In this paper we present an automatic method for detecting the rectum and sigmoid colon limit using a novel global curvature analysis over the centerline of the segmented digestive tube in different imaging modalities. The results are compared with the gold standard rectum upper limit through a validation scheme comprising two different anatomical markers: the third sacral vertebra and the average rectum length. Experimental results in both magnetic resonance imaging (MRI) and computed tomography colonography (CTC) acquisitions show the efficacy of the proposed strategy in automatic detection of rectum limits. The method is intended for application to the rectum segmentation in MRI for geometrical modeling and as contextual information source in virtual colonoscopies and CAD systems. Copyright © 2014 Elsevier Ltd. All rights reserved.

Teleradiology applications with DICOM-e-mail.

PubMed

Weisser, G; Engelmann, U; Ruggiero, S; Runa, A; Schröter, A; Baur, S; Walz, M

2007-05-01

For the connection of several partners to a Dicom-e-mail based teleradiology network concepts were developed to allow the integration of different teleradiology applications. The organisational and technical needs for such an integration were analysed. More than 60 institutions including 23 hospitals in the Rhein-Neckar-Region, Germany were connected. The needed functionality was grouped in six teleradiology applications (emergency consultation, tele-guided examinations, expert consultations, cooperative work, scientific cooperations and homework with on call services) and their technical and organisational needs according to availability, speed of transfer, workflow definitions and data security needs was analysed. For the local integration of teleradiology services the setup and workflow is presented for a standalone teleradiology workstation and a server based teleradiology gateway. The line type needed for different groups of applications and users is defined. The security concept and fallback strategies are laid out, potential security problems and sources of errors are discussed. The specialties for the emergency teleradiology application are presented. The DICOM-e-mail protocol is a flexible and powerful protocol that can be used for a variety of teleradiology applications. It can meet the conditions for emergency applications but is limited if synchronous applications like teleconferences are needed.

47 CFR 76.502 - Time limits applicable to franchise authority consideration of transfer applications.

Code of Federal Regulations, 2010 CFR

2010-10-01

... 47 Telecommunication 4 2010-10-01 2010-10-01 false Time limits applicable to franchise authority... Cable Systems § 76.502 Time limits applicable to franchise authority consideration of transfer applications. (a) A franchise authority shall have 120 days from the date of submission of a completed FCC Form...

47 CFR 76.502 - Time limits applicable to franchise authority consideration of transfer applications.

Code of Federal Regulations, 2014 CFR

2014-10-01

... 47 Telecommunication 4 2014-10-01 2014-10-01 false Time limits applicable to franchise authority... Cable Systems § 76.502 Time limits applicable to franchise authority consideration of transfer applications. (a) A franchise authority shall have 120 days from the date of submission of a completed FCC Form...

Designing Mobile Applications for Emergency Response: Citizens Acting as Human Sensors

PubMed Central

Romano, Marco; Onorati, Teresa; Aedo, Ignacio; Diaz, Paloma

2016-01-01

When an emergency occurs, citizens can be a helpful support for the operation centers involved in the response activities. As witnesses to a crisis, they initially can share updated and detailed information about what is going on. Moreover, thanks to the current technological evolution people are able to quickly and easily gather rich information and transmit it through different communication channels. Indeed, modern mobile devices embed several sensors such as GPS receivers, Wi-Fi, accelerometers or cameras that can transform users into well-equipped human sensors. For these reasons, emergency organizations and small and medium enterprises have demonstrated a growing interest in developing smart applications for reporting any exceptional circumstances. In this paper, we present a practical study about this kind of applications for identifying both limitations and common features. Based on a study of relevant existent contributions in this area and our personal direct experience in developing and evaluating emergency management solutions, our aim is to propose several findings about how to design effective and efficient mobile emergency notification applications. For this purpose we have exploited the basic sensors of modern mobile devices and the users’ aptitude for using them. The evaluation consists of a practical and a theoretical part. In the practical part, we have simulated a traffic accident as closely as possible to a real scenario, with a victim lying on the ground near a car in the middle of a street. For the theoretical part, we have interviewed some emergency experts for collecting their opinions about the utility of the proposed solution. Results from this evaluation phase confirm the positive impact that EN application have for both operators’ and citizens’ perspective. Moreover, we collected several findings useful for future design challenges in the same area, as shown in the final redesign of the proposed application. PMID:27007375

Helicopter noise regulations: An industry perspective

NASA Technical Reports Server (NTRS)

Wagner, R. A.

1978-01-01

A review of helicopter noise measurement programs and noise reduction/economic studies of FAA is given along with a critique of a study which addresses the economic impact of noise reduction on helicopter noise. Modification of several helicopters to reduce noise and demonstrate the economic impact of the application of the current state-of-the-art technology is discussed. Specific helicopters described include Boeing Vertol 347 Helicopter, Hughes OH-6 Helicopter, and Hughes 269C Helicopter. Other topics covered include: (1) noise trends and possible noise limits; (2) accuracy of helicopter noise prediction techniques; (3) limited change possibilities of derivatives; and (4) rotor impulsive noise. The unique operational capabilities of helicopters and the implications relative to noise regulations and certification are discussed.

Stibathiolanes: Synthesis, solid state structure, and solution behavior

NASA Astrophysics Data System (ADS)

Fisher, Richard A.; Nielsen, Ralph B.; Davis, William M.; Buchwald, Stephen L.

1990-06-01

Interest in organometallic compounds of the main group metals has recently grown tremendously, due in part to the wide variety of applications of these compounds in the materials sciences. Despite this new activity, the synthetic strategies for main group organometallics have remained relatively undeveloped. The majority of syntheses of these compounds involve classical metathesis reactions between a main group halide and an organometallic compound such as an organolithium or Grignard reagent and are limited by a lack of selectivity and by the availability of suitable organometallic precursors. The latter limitation is severe for main group metallacycles because of the paucity of suitable 1, n(n=3,4,5)-dianionic reagents or their equivalents, which are most often used for the synthesis of this class of molecules.

Redundant manipulator techniques for partially decentralized path planning and control of a platoon of autonomous vehicles.

PubMed

Stilwell, Daniel J; Bishop, Bradley E; Sylvester, Caleb A

2005-08-01

An approach to real-time trajectory generation for platoons of autonomous vehicles is developed from well-known control techniques for redundant robotic manipulators. The partially decentralized structure of this approach permits each vehicle to independently compute its trajectory in real-time using only locally generated information and low-bandwidth feedback generated by a system exogenous to the platoon. Our work is motivated by applications for which communications bandwidth is severely limited, such for platoons of autonomous underwater vehicles. The communication requirements for our trajectory generation approach are independent of the number of vehicles in the platoon, enabling platoons composed of a large number of vehicles to be coordinated despite limited communication bandwidth.

Dynamic power scheduling system for JPEG2000 delivery over wireless networks

NASA Astrophysics Data System (ADS)

Martina, Maurizio; Vacca, Fabrizio

2003-06-01

Third generation mobile terminals diffusion is encouraging the development of new multimedia based applications. The reliable transmission of audiovisual content will gain major interest being one of the most valuable services. Nevertheless, mobile scenario is severely power constrained: high compression ratios and refined energy management strategies are highly advisable. JPEG2000 as the source encoding stage assures excellent performance with extremely good visual quality. However the limited power budged imposes to limit the computational effort in order to save as much power as possible. Starting from an error prone environment, as the wireless one, high error-resilience features need to be employed. This paper tries to investigate the trade-off between quality and power in such a challenging environment.

[Advance directives in clinical practice : Living will, healthcare power of attorney and care directive].

PubMed

Hack, J; Buecking, B; Lopez, C L; Ruchholtz, S; Kühne, C A

2017-06-01

In clinical practice, situations continuously occur in which medical professionals and family members are confronted with decisions on whether to extend or limit treatment for severely ill patients in end of life treatment decisions. In these situations, advance directives are helpful tools in decision making according to the wishes of the patient; however, not every patient has made an advance directive and in our experience medical staff as well as patients are often not familiar with these documents. The purpose of this article is therefore to explain the currently available documents (e.g. living will, healthcare power of attorney and care directive) and the possible (legal) applications and limitations in the routine clinical practice.

[Advance directives in clinical practice : Living will, healthcare power of attorney and care directive].

PubMed

Hack, J; Buecking, B; Lopez, C L; Ruchholtz, S; Kühne, C A

2017-02-01

In clinical practice, situations continuously occur in which medical professionals and family members are confronted with decisions on whether to extend or limit treatment for severely ill patients in end of life treatment decisions. In these situations, advance directives are helpful tools in decision making according to the wishes of the patient; however, not every patient has made an advance directive and in our experience medical staff as well as patients are often not familiar with these documents. The purpose of this article is therefore to explain the currently available documents (e.g. living will, healthcare power of attorney and care directive) and the possible (legal) applications and limitations in the routine clinical practice.

[Advance directives in clinical practice : Living will, healthcare power of attorney and care directive].

PubMed

Hack, J; Buecking, B; Lopez, C L; Ruchholtz, S; Kühne, C A

2017-12-01

In clinical practice, situations continuously occur in which medical professionals and family members are confronted with decisions on whether to extend or limit treatment for severely ill patients in end of life treatment decisions. In these situations, advance directives are helpful tools in decision making according to the wishes of the patient; however, not every patient has made an advance directive and in our experience medical staff as well as patients are often not familiar with these documents. The purpose of this article is therefore to explain the currently available documents (e.g. living will, healthcare power of attorney and care directive) and the possible (legal) applications and limitations in the routine clinical practice.

[Advance directives in clinical practice : Living will, healthcare power of attorney and care directive].

PubMed

Hack, J; Buecking, B; Lopez, C L; Ruchholtz, S; Kühne, C A

2017-04-01

In clinical practice, situations continuously occur in which medical professionals and family members are confronted with decisions on whether to extend or limit treatment for severely ill patients in end of life treatment decisions. In these situations, advance directives are helpful tools in decision making according to the wishes of the patient; however, not every patient has made an advance directive and in our experience medical staff as well as patients are often not familiar with these documents. The purpose of this article is therefore to explain the currently available documents (e.g. living will, healthcare power of attorney and care directive) and the possible (legal) applications and limitations in the routine clinical practice.

Functional imaging for regenerative medicine.

PubMed

Leahy, Martin; Thompson, Kerry; Zafar, Haroon; Alexandrov, Sergey; Foley, Mark; O'Flatharta, Cathal; Dockery, Peter

2016-04-19

In vivo imaging is a platform technology with the power to put function in its natural structural context. With the drive to translate stem cell therapies into pre-clinical and clinical trials, early selection of the right imaging techniques is paramount to success. There are many instances in regenerative medicine where the biological, biochemical, and biomechanical mechanisms behind the proposed function of stem cell therapies can be elucidated by appropriate imaging. Imaging techniques can be divided according to whether labels are used and as to whether the imaging can be done in vivo. In vivo human imaging places additional restrictions on the imaging tools that can be used. Microscopies and nanoscopies, especially those requiring fluorescent markers, have made an extraordinary impact on discovery at the molecular and cellular level, but due to their very limited ability to focus in the scattering tissues encountered for in vivo applications they are largely confined to superficial imaging applications in research laboratories. Nanoscopy, which has tremendous benefits in resolution, is limited to the near-field (e.g. near-field scanning optical microscope (NSNOM)) or to very high light intensity (e.g. stimulated emission depletion (STED)) or to slow stochastic events (photo-activated localization microscopy (PALM) and stochastic optical reconstruction microscopy (STORM)). In all cases, nanoscopy is limited to very superficial applications. Imaging depth may be increased using multiphoton or coherence gating tricks. Scattering dominates the limitation on imaging depth in most tissues and this can be mitigated by the application of optical clearing techniques that can impose mild (e.g. topical application of glycerol) or severe (e.g. CLARITY) changes to the tissue to be imaged. Progression of therapies through to clinical trials requires some thought as to the imaging and sensing modalities that should be used. Smoother progression is facilitated by the use of comparable imaging modalities throughout the discovery and trial phases, giving label-free techniques an advantage wherever they can be used, although this is seldom considered in the early stages. In this paper, we will explore the techniques that have found success in aiding discovery in stem cell therapies and try to predict the likely technologies best suited to translation and future directions.

A speech-controlled environmental control system for people with severe dysarthria.

PubMed

Hawley, Mark S; Enderby, Pam; Green, Phil; Cunningham, Stuart; Brownsell, Simon; Carmichael, James; Parker, Mark; Hatzis, Athanassios; O'Neill, Peter; Palmer, Rebecca

2007-06-01

Automatic speech recognition (ASR) can provide a rapid means of controlling electronic assistive technology. Off-the-shelf ASR systems function poorly for users with severe dysarthria because of the increased variability of their articulations. We have developed a limited vocabulary speaker dependent speech recognition application which has greater tolerance to variability of speech, coupled with a computerised training package which assists dysarthric speakers to improve the consistency of their vocalisations and provides more data for recogniser training. These applications, and their implementation as the interface for a speech-controlled environmental control system (ECS), are described. The results of field trials to evaluate the training program and the speech-controlled ECS are presented. The user-training phase increased the recognition rate from 88.5% to 95.4% (p<0.001). Recognition rates were good for people with even the most severe dysarthria in everyday usage in the home (mean word recognition rate 86.9%). Speech-controlled ECS were less accurate (mean task completion accuracy 78.6% versus 94.8%) but were faster to use than switch-scanning systems, even taking into account the need to repeat unsuccessful operations (mean task completion time 7.7s versus 16.9s, p<0.001). It is concluded that a speech-controlled ECS is a viable alternative to switch-scanning systems for some people with severe dysarthria and would lead, in many cases, to more efficient control of the home.

Dynamic Loading of Substation Distribution Transformers: An Application for use in a Production Grade Environment

NASA Astrophysics Data System (ADS)

Zhang, Ming

Recent trends in the electric power industry have led to more attention to optimal operation of power transformers. In a deregulated environment, optimal operation means minimizing the maintenance and extending the life of this critical and costly equipment for the purpose of maximizing profits. Optimal utilization of a transformer can be achieved through the use of dynamic loading. A benefit of dynamic loading is that it allows better utilization of the transformer capacity, thus increasing the flexibility and reliability of the power system. This document presents the progress on a software application which can estimate the maximum time-varying loading capability of transformers. This information can be used to load devices closer to their limits without exceeding the manufacturer specified operating limits. The maximally efficient dynamic loading of transformers requires a model that can accurately predict both top-oil temperatures (TOTs) and hottest-spot temperatures (HSTs). In the previous work, two kinds of thermal TOT and HST models have been studied and used in the application: the IEEE TOT/HST models and the ASU TOT/HST models. And, several metrics have been applied to evaluate the model acceptability and determine the most appropriate models for using in the dynamic loading calculations. In this work, an investigation to improve the existing transformer thermal models performance is presented. Some factors that may affect the model performance such as improper fan status and the error caused by the poor performance of IEEE models are discussed. Additional methods to determine the reliability of transformer thermal models using metrics such as time constant and the model parameters are also provided. A new production grade application for real-time dynamic loading operating purpose is introduced. This application is developed by using an existing planning application, TTeMP, as a start point, which is designed for the dispatchers and load specialists. To overcome the limitations of TTeMP, the new application can perform dynamic loading under emergency conditions, such as loss-of transformer loading. It also has the capability to determine the emergency rating of the transformers for a real-time estimation.

Animal models of intellectual disability: towards a translational approach

PubMed Central

Scorza, Carla A; Cavalheiro, Esper A.

2011-01-01

Intellectual disability is a prevalent form of cognitive impairment, affecting 2–3% of the general population. It is a daunting societal problem characterized by significant limitations both in intellectual functioning and in adaptive behavior as expressed in conceptual, social and practical adaptive skills. Intellectual disability is a clinically important disorder for which the etiology and pathogenesis are still poorly understood. Moreover, although tremendous progress has been made, pharmacological intervention is still currently non-existent and therapeutic strategies remain limited. Studies in humans have a very limited capacity to explain basic mechanisms of this condition. In this sense, animal models have been invaluable in intellectual disability investigation. Certainly, a great deal of the knowledge that has improved our understanding of several pathologies has derived from appropriate animal models. Moreover, to improve human health, scientific discoveries must be translated into practical applications. Translational research specifically aims at taking basic scientific discoveries and best practices to benefit the lives of people in our communities. In this context, the challenge that basic science research needs to meet is to make use of a comparative approach to benefit the most from what each animal model can tell us. Intellectual disability results from many different genetic and environmental insults. Taken together, the present review will describe several animal models of potential intellectual disability risk factors. PMID:21779723

Single-Step 3-D Image Reconstruction in Magnetic Induction Tomography: Theoretical Limits of Spatial Resolution and Contrast to Noise Ratio

PubMed Central

Hollaus, Karl; Rosell-Ferrer, Javier; Merwa, Robert

2006-01-01

Magnetic induction tomography (MIT) is a low-resolution imaging modality for reconstructing the changes of the complex conductivity in an object. MIT is based on determining the perturbation of an alternating magnetic field, which is coupled from several excitation coils to the object. The conductivity distribution is reconstructed from the corresponding voltage changes induced in several receiver coils. Potential medical applications comprise the continuous, non-invasive monitoring of tissue alterations which are reflected in the change of the conductivity, e.g. edema, ventilation disorders, wound healing and ischemic processes. MIT requires the solution of an ill-posed inverse eddy current problem. A linearized version of this problem was solved for 16 excitation coils and 32 receiver coils with a model of two spherical perturbations within a cylindrical phantom. The method was tested with simulated measurement data. Images were reconstructed with a regularized single-step Gauss–Newton approach. Theoretical limits for spatial resolution and contrast/noise ratio were calculated and compared with the empirical results from a Monte-Carlo study. The conductivity perturbations inside a homogeneous cylinder were localized for a SNR between 44 and 64 dB. The results prove the feasibility of difference imaging with MIT and give some quantitative data on the limitations of the method. PMID:17031597

The Search for Muon Neutrinos from Northern Hemisphere Gamma-Ray Bursts with AMANDA

NASA Astrophysics Data System (ADS)

Achterberg, A.; Ackermann, M.; Adams, J.; Ahrens, J.; Andeen, K.; Auffenberg, J.; Bahcall, J. N.; Bai, X.; Baret, B.; Barwick, S. W.; Bay, R.; Beattie, K.; Becka, T.; Becker, J. K.; Becker, K.-H.; Berghaus, P.; Berley, D.; Bernardini, E.; Bertrand, D.; Besson, D. Z.; Blaufuss, E.; Boersma, D. J.; Bohm, C.; Bolmont, J.; Böser, S.; Botner, O.; Bouchta, A.; Braun, J.; Burgess, C.; Burgess, T.; Castermans, T.; Chirkin, D.; Christy, B.; Clem, J.; Cowen, D. F.; D'Agostino, M. V.; Davour, A.; Day, C. T.; De Clercq, C.; Demirörs, L.; Descamps, F.; Desiati, P.; DeYoung, T.; Diaz-Velez, J. C.; Dreyer, J.; Dumm, J. P.; Duvoort, M. R.; Edwards, W. R.; Ehrlich, R.; Eisch, J.; Ellsworth, R. W.; Evenson, P. A.; Fadiran, O.; Fazely, A. R.; Filimonov, K.; Foerster, M. M.; Fox, B. D.; Franckowiak, A.; Gaisser, T. K.; Gallagher, J.; Ganugapati, R.; Geenen, H.; Gerhardt, L.; Goldschmidt, A.; Goodman, J. A.; Gozzini, R.; Griesel, T.; Gross, A.; Grullon, S.; Gunasingha, R. M.; Gurtner, M.; Hallgren, A.; Halzen, F.; Han, K.; Hanson, K.; Hardtke, D.; Hardtke, R.; Hart, J. E.; Hasegawa, Y.; Hauschildt, T.; Hays, D.; Heise, J.; Helbing, K.; Hellwig, M.; Herquet, P.; Hill, G. C.; Hodges, J.; Hoffman, K. D.; Hommez, B.; Hoshina, K.; Hubert, D.; Hughey, B.; Hulth, P. O.; Hülss, J.-P.; Hultqvist, K.; Hundertmark, S.; Inaba, M.; Ishihara, A.; Jacobsen, J.; Japaridze, G. S.; Johansson, H.; Jones, A.; Joseph, J. M.; Kampert, K.-H.; Kappes, A.; Karg, T.; Karle, A.; Kawai, H.; Kelley, J. L.; Kitamura, N.; Klein, S. R.; Klepser, S.; Kohnen, G.; Kolanoski, H.; Köpke, L.; Kowalski, M.; Kowarik, T.; Krasberg, M.; Kuehn, K.; Labare, M.; Landsman, H.; Leich, H.; Leier, D.; Liubarsky, I.; Lundberg, J.; Lünemann, J.; Madsen, J.; Mase, K.; Matis, H. S.; McCauley, T.; McParland, C. P.; Meli, A.; Messarius, T.; Mészáros, P.; Miyamoto, H.; Mokhtarani, A.; Montaruli, T.; Morey, A.; Morse, R.; Movit, S. M.; Münich, K.; Nahnhauer, R.; Nam, J. W.; Niessen, P.; Nygren, D. R.; Ögelman, H.; Olivas, A.; Patton, S.; Peña-Garay, C.; Pérez de los Heros, C.; Piegsa, A.; Pieloth, D.; Pohl, A. C.; Porrata, R.; Pretz, J.; Price, P. B.; Przybylski, G. T.; Rawlins, K.; Razzaque, S.; Resconi, E.; Rhode, W.; Ribordy, M.; Rizzo, A.; Robbins, S.; Roth, P.; Rott, C.; Rutledge, D.; Ryckbosch, D.; Sander, H.-G.; Sarkar, S.; Schlenstedt, S.; Schmidt, T.; Schneider, D.; Seckel, D.; Semburg, B.; Seo, S. H.; Seunarine, S.; Silvestri, A.; Smith, A. J.; Solarz, M.; Song, C.; Sopher, J. E.; Spiczak, G. M.; Spiering, C.; Stamatikos, M.; Stanev, T.; Steffen, P.; Stezelberger, T.; Stokstad, R. G.; Stoufer, M. C.; Stoyanov, S.; Strahler, E. A.; Straszheim, T.; Sulanke, K.-H.; Sullivan, G. W.; Sumner, T. J.; Taboada, I.; Tarasova, O.; Tepe, A.; Thollander, L.; Tilav, S.; Tluczykont, M.; Toale, P. A.; Turčan, D.; van Eijndhoven, N.; Vandenbroucke, J.; Van Overloop, A.; Viscomi, V.; Voigt, B.; Wagner, W.; Walck, C.; Waldmann, H.; Walter, M.; Wang, Y.-R.; Wendt, C.; Wiebusch, C. H.; Wikström, G.; Williams, D. R.; Wischnewski, R.; Wissing, H.; Woschnagg, K.; Xu, X. W.; Yodh, G.; Yoshida, S.; Zornoza, J. D.; Interplanetary Network, The

2008-02-01

We present the results of the analysis of neutrino observations by the Antarctic Muon and Neutrino Detector Array (AMANDA) correlated with photon observations of more than 400 gamma-ray bursts (GRBs) in the northern hemisphere from 1997 to 2003. During this time period, AMANDA's effective collection area for muon neutrinos was larger than that of any other existing detector. After the application of various selection criteria to our data, we expect ~1 neutrino event and <2 background events. Based on our observations of zero events during and immediately prior to the GRBs in the data set, we set the most stringent upper limit on muon neutrino emission correlated with GRBs. Assuming a Waxman-Bahcall spectrum and incorporating all systematic uncertainties, our flux upper limit has a normalization at 1 PeV of E2Φν <= 6.3 × 10-9 GeV cm-2 s-1 sr-1, with 90% of the events expected within the energy range of ~10 TeV to ~3 PeV. The impact of this limit on several theoretical models of GRBs is discussed, as well as the future potential for detection of GRBs by next-generation neutrino telescopes. Finally, we briefly describe several modifications to this analysis in order to apply it to other types of transient point sources.

Pulsed magnetization transfer imaging with body coil transmission at 3 Tesla: feasibility and application.

PubMed

Smith, Seth A; Farrell, Jonathan A D; Jones, Craig K; Reich, Daniel S; Calabresi, Peter A; van Zijl, Peter C M

2006-10-01

Pulsed magnetization transfer (MT) imaging has been applied to quantitatively assess brain pathology in several diseases, especially multiple sclerosis (MS). To date, however, because of the high power deposition associated with the use of short, rapidly repeating MT prepulses, clinical application has been limited to lower field strengths. The contrast-to-noise ratio (CNR) of MT is limited, and this method would greatly benefit from the use of higher magnetic fields and phased-array coil reception. However, power deposition is proportional to the square of the magnetic field and scales with coil size, and MT experiments are already close to the SAR limit at 1.5T even when smaller transmit coils are used instead of the body coil. Here we show that these seemingly great obstacles can be ameliorated by the increased T(1) of tissue water at higher field, which allows for longer maintenance of sufficiently high saturation levels while using a reduced duty cycle. This enables a fast (5-6 min) high-resolution (1.5 mm isotropic) whole-brain MT acquisition with excellent anatomical visualization of gray matter (GM) and white matter (WM) structures, and even substructures. The method is demonstrated in nine normal volunteers and five patients with relapsing remitting MS (RRMS), and the results show a clear delineation of heterogeneous lesions.

Lanthanide‐Doped Upconversion Nanoparticles: Emerging Intelligent Light‐Activated Drug Delivery Systems

PubMed Central

Bagheri, Ali; Arandiyan, Hamidreza

2016-01-01

The development of drug delivery systems (DDSs) using near infrared (NIR) light and upconversion nanoparticles (UCNPs) has generated intensive interest over the past five years. These NIR‐initiated DDSs not only offer a high degree of spatial and temporal determination of therapeutic release but also provide precise control over the released dosage. Furthermore, these nanoplatforms confer several advantages over conventional light‐based DDSs—NIR offers better tissue penetration depth and a reduced risk of cellular photo‐damage caused by exposure to light at high‐energy wavelengths (e.g., ultraviolet light, <400 nm). The development of DDSs that can be activated by low intensity NIR illumination is highly desirable to avoid exposing living tissues to excessive heat that can limit the in vivo application of these DDSs. This encompasses research in three directions: (i) enhancing the quantum yield of the UCNPs; (ii) incorporation of photo‐responsive materials with red‐shifted absorptions into the UCNPs; and (iii) tuning the UCNPs excitation wavelength. This review focuses on recent advances in the development of NIR‐initiated DDS, with emphasis on the use of photo‐responsive compounds and polymeric materials conjugated onto UCNPs. The challenges that limit UCNPs clinical applications, alongside with the aforementioned techniques that have emerged to overcome these limitations, are highlighted. PMID:27818904

Charging performance of automotive batteries-An underestimated factor influencing lifetime and reliable battery operation

NASA Astrophysics Data System (ADS)

Sauer, Dirk Uwe; Karden, Eckhard; Fricke, Birger; Blanke, Holger; Thele, Marc; Bohlen, Oliver; Schiffer, Julia; Gerschler, Jochen Bernhard; Kaiser, Rudi

Dynamic charge acceptance and charge acceptance under constant voltage charging conditions are for two reasons essential for lead-acid battery operation: energy efficiency in applications with limited charging time (e.g. PV systems or regenerative braking in vehicles) and avoidance of accelerated ageing due to sulphation. Laboratory tests often use charge regimes which are beneficial for the battery life, but which differ significantly from the operating conditions in the field. Lead-acid batteries in applications with limited charging time and partial-state-of-charge operation are rarely fully charged due to their limited charge acceptance. Therefore, they suffer from sulphation and early capacity loss. However, when appropriate charging strategies are applied most of the lost capacity and thus performance for the user may be recovered. The paper presents several aspects of charging regimes and charge acceptance. Theoretical and experimental investigations show that temperature is the most critical parameter. Full charging within short times can be achieved only at elevated temperatures. A strong dependency of the charge acceptance during charging pulses on the pre-treatment of the battery can be observed, which is not yet fully understood. But these effects have a significant impact on the fuel efficiency of micro-hybrid electric vehicles.

Improved wavefront correction for coherent image restoration.

PubMed

Zelenka, Claudius; Koch, Reinhard

2017-08-07

Coherent imaging has a wide range of applications in, for example, microscopy, astronomy, and radar imaging. Particularly interesting is the field of microscopy, where the optical quality of the lens is the main limiting factor. In this article, novel algorithms for the restoration of blurred images in a system with known optical aberrations are presented. Physically motivated by the scalar diffraction theory, the new algorithms are based on Haugazeau POCS and FISTA, and are faster and more robust than methods presented earlier. With the new approach the level of restoration quality on real images is very high, thereby blurring and ringing caused by defocus can be effectively removed. In classical microscopy, lenses with very low aberration must be used, which puts a practical limit on their size and numerical aperture. A coherent microscope using the novel restoration method overcomes this limitation. In contrast to incoherent microscopy, severe optical aberrations including defocus can be removed, hence the requirements on the quality of the optics are lower. This can be exploited for an essential price reduction of the optical system. It can be also used to achieve higher resolution than in classical microscopy, using lenses with high numerical aperture and high aberration. All this makes the coherent microscopy superior to the traditional incoherent in suited applications.

Synthesis of high-quality libraries of long (150mer) oligonucleotides by a novel depurination controlled process

PubMed Central

LeProust, Emily M.; Peck, Bill J.; Spirin, Konstantin; McCuen, Heather Brummel; Moore, Bridget; Namsaraev, Eugeni; Caruthers, Marvin H.

2010-01-01

We have achieved the ability to synthesize thousands of unique, long oligonucleotides (150mers) in fmol amounts using parallel synthesis of DNA on microarrays. The sequence accuracy of the oligonucleotides in such large-scale syntheses has been limited by the yields and side reactions of the DNA synthesis process used. While there has been significant demand for libraries of long oligos (150mer and more), the yields in conventional DNA synthesis and the associated side reactions have previously limited the availability of oligonucleotide pools to lengths <100 nt. Using novel array based depurination assays, we show that the depurination side reaction is the limiting factor for the synthesis of libraries of long oligonucleotides on Agilent Technologies’ SurePrint® DNA microarray platform. We also demonstrate how depurination can be controlled and reduced by a novel detritylation process to enable the synthesis of high quality, long (150mer) oligonucleotide libraries and we report the characterization of synthesis efficiency for such libraries. Oligonucleotide libraries prepared with this method have changed the economics and availability of several existing applications (e.g. targeted resequencing, preparation of shRNA libraries, site-directed mutagenesis), and have the potential to enable even more novel applications (e.g. high-complexity synthetic biology). PMID:20308161

The application of multiple reaction monitoring and multi-analyte profiling to HDL proteins

PubMed Central

2014-01-01

Background HDL carries a rich protein cargo and examining HDL protein composition promises to improve our understanding of its functions. Conventional mass spectrometry methods can be lengthy and difficult to extend to large populations. In addition, without prior enrichment of the sample, the ability of these methods to detect low abundance proteins is limited. Our objective was to develop a high-throughput approach to examine HDL protein composition applicable to diabetes and cardiovascular disease (CVD). Methods We optimized two multiplexed assays to examine HDL proteins using a quantitative immunoassay (Multi-Analyte Profiling- MAP) and mass spectrometric-based quantitative proteomics (Multiple Reaction Monitoring-MRM). We screened HDL proteins using human xMAP (90 protein panel) and MRM (56 protein panel). We extended the application of these two methods to HDL isolated from a group of participants with diabetes and prior cardiovascular events and a group of non-diabetic controls. Results We were able to quantitate 69 HDL proteins using MAP and 32 proteins using MRM. For several common proteins, the use of MRM and MAP was highly correlated (p < 0.01). Using MAP, several low abundance proteins implicated in atherosclerosis and inflammation were found on HDL. On the other hand, MRM allowed the examination of several HDL proteins not available by MAP. Conclusions MAP and MRM offer a sensitive and high-throughput approach to examine changes in HDL proteins in diabetes and CVD. This approach can be used to measure the presented HDL proteins in large clinical studies. PMID:24397693

A human-oriented framework for developing assistive service robots.

PubMed

McGinn, Conor; Cullinan, Michael F; Culleton, Mark; Kelly, Kevin

2018-04-01

Multipurpose robots that can perform a range of useful tasks have the potential to increase the quality of life for many people living with disabilities. Owing to factors such as high system complexity, as-yet unresolved research questions and current technology limitations, there is a need for effective strategies to coordinate the development process. Integrating established methodologies based on human-centred design and universal design, a framework was formulated to coordinate the robot design process over successive iterations of prototype development. An account is given of how the framework was practically applied to the problem of developing a personal service robot. Application of the framework led to the formation of several design goals which addressed a wide range of identified user needs. The resultant prototype solution, which consisted of several component elements, succeeded in demonstrating the performance stipulated by all of the proposed metrics. Application of the framework resulted in the development of a complex prototype that addressed many aspects of the functional and usability requirements of a personal service robot. Following the process led to several important insights which directly benefit the development of subsequent prototypes. Implications for Rehabilitation This research shows how universal design might be used to formulate usability requirements for assistive service robots. A framework is presented that guides the process of designing service robots in a human-centred way. Through practical application of the framework, a prototype robot system that addressed a range of identified user needs was developed.

Microbial surfactants: fundamentals and applicability in the formulation of nano-sized drug delivery vectors.

PubMed

Rodrigues, Ligia R

2015-07-01

Microbial surfactants, so-called biosurfactants, comprise a wide variety of structurally distinct amphipathic molecules produced by several microorganisms. Besides exhibiting surface activity at the interfaces, these molecules present powerful characteristics including high biodegradability, low toxicity and special biological activities (e.g. antimicrobial, antiviral, anticancer, among others), that make them an alternative to their chemical counterparts. Several medical-related applications have been suggested for these molecules, including some reports on their potential use in the formulation of nano-sized drug delivery vectors. However, despite their promises, due to the generalized lack of knowledge on microbial surfactants phase behavior and stability under diverse physicochemical conditions, these applications remain largely unexplored, thus representing an exciting field of research. These nano-sized vectors are a powerful approach towards the current medical challenges regarding the development of efficient and targeted treatments for several diseases. In this review, a special emphasis will be given to nanoparticles and microemulsions. Nanoparticles are very auspicious as their size, shape and stability can be manipulated by changing the environmental conditions. On the other hand, the easiness of formulation, as well as the broad possibilities of administration justifies the recent popularity of the microemulsions. Notwithstanding, both vector types still require further developments to overcome some critical limitations related with toxicity and costs, among others. Such developments may include the search for other system components, as the microbial surfactants, that can display improved features. Copyright © 2015 Elsevier Inc. All rights reserved.

Noise analysis for near field 3-D FM-CW radar imaging systems

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

Sheen, David M.

2015-06-19

Near field radar imaging systems are used for several applications including concealed weapon detection in airports and other high-security venues. Despite the near-field operation, phase noise and thermal noise can limit the performance in several ways including reduction in system sensitivity and reduction of image dynamic range. In this paper, the effects of thermal noise, phase noise, and processing gain are analyzed in the context of a near field 3-D FM-CW imaging radar as might be used for concealed weapon detection. In addition to traditional frequency domain analysis, a time-domain simulation is employed to graphically demonstrate the effect of thesemore » noise sources on a fast-chirping FM-CW system.« less

Three-Dimensional Images For Robot Vision

NASA Astrophysics Data System (ADS)

McFarland, William D.

1983-12-01

Robots are attracting increased attention in the industrial productivity crisis. As one significant approach for this nation to maintain technological leadership, the need for robot vision has become critical. The "blind" robot, while occupying an economical niche at present is severely limited and job specific, being only one step up from the numerical controlled machines. To successfully satisfy robot vision requirements a three dimensional representation of a real scene must be provided. Several image acquistion techniques are discussed with more emphasis on the laser radar type instruments. The autonomous vehicle is also discussed as a robot form, and the requirements for these applications are considered. The total computer vision system requirement is reviewed with some discussion of the major techniques in the literature for three dimensional scene analysis.

Rapid trifluoromethylation and perfluoroalkylation of five-membered heterocycles by photoredox catalysis in continuous flow.

PubMed

Straathof, Natan J W; Gemoets, Hannes P L; Wang, Xiao; Schouten, Jaap C; Hessel, Volker; Noël, Timothy

2014-06-01

Trifluoromethylated and perfluoroalkylated heterocycles are important building blocks for the synthesis of numerous pharmaceutical products, agrochemicals and are widely applied in material sciences. To date, trifluoromethylated and perfluoroalkylated hetero-aromatic systems can be prepared utilizing visible light photoredox catalysis methodologies in batch. While several limitations are associated with these batch protocols, the application of microflow technology could greatly enhance and intensify these reactions. A simple and straightforward photocatalytic trifluoromethylation and perfluoroalkylation method has been developed in continuous microflow, using commercially available photocatalysts and microflow components. A selection of five-membered hetero-aromatics were successfully trifluoromethylated (12 examples) and perfluoroalkylated (5 examples) within several minutes (8-20 min). © 2014 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

Exploration for fossil and nuclear fuels from orbital altitudes

NASA Technical Reports Server (NTRS)

Short, N. M.; Tiedemann, H. A.

1975-01-01

Studies of LANDSAT and Skylab-EREP data have defined both the advantages and limitations of space platforms as a new 'tool' in mineral exploration. One LANDSAT investigation in the Anadarko Basin of Oklahoma has demonstrated a correlation between several types of anomalies recognized in the imagery and the locations of known oil and gas fields. In addition to supporting several LANDSAT follow-on investigations in petroleum exploration, NASA has approved a broad in-house study at Goddard Space Flight Center designed to verify the general applicability of the initial Anadarko Basin results. Using both conventional photogeologic methods and special computer processing, imagery taken over oil-producing areas is being subjected to detailed analysis in search of definitive recognition criteria.

Application of Non-Deterministic Methods to Assess Modeling Uncertainties for Reinforced Carbon-Carbon Debris Impacts

NASA Technical Reports Server (NTRS)

Lyle, Karen H.; Fasanella, Edwin L.; Melis, Matthew; Carney, Kelly; Gabrys, Jonathan

2004-01-01

The Space Shuttle Columbia Accident Investigation Board (CAIB) made several recommendations for improving the NASA Space Shuttle Program. An extensive experimental and analytical program has been developed to address two recommendations related to structural impact analysis. The objective of the present work is to demonstrate the application of probabilistic analysis to assess the effect of uncertainties on debris impacts on Space Shuttle Reinforced Carbon-Carbon (RCC) panels. The probabilistic analysis is used to identify the material modeling parameters controlling the uncertainty. A comparison of the finite element results with limited experimental data provided confidence that the simulations were adequately representing the global response of the material. Five input parameters were identified as significantly controlling the response.

Investigating the Effects of the Interaction Intensity in a Weak Measurement.

PubMed

Piacentini, Fabrizio; Avella, Alessio; Gramegna, Marco; Lussana, Rudi; Villa, Federica; Tosi, Alberto; Brida, Giorgio; Degiovanni, Ivo Pietro; Genovese, Marco

2018-05-03

Measurements are crucial in quantum mechanics, for fundamental research as well as for applicative fields like quantum metrology, quantum-enhanced measurements and other quantum technologies. In the recent years, weak-interaction-based protocols like Weak Measurements and Protective Measurements have been experimentally realized, showing peculiar features leading to surprising advantages in several different applications. In this work we analyze the validity range for such measurement protocols, that is, how the interaction strength affects the weak value extraction, by measuring different polarization weak values on heralded single photons. We show that, even in the weak interaction regime, the coupling intensity limits the range of weak values achievable, setting a threshold on the signal amplification effect exploited in many weak measurement based experiments.

Unlocking the Potential of Poly(Ortho Ester)s: A General Catalytic Approach to the Synthesis of Surface‐Erodible Materials

PubMed Central

Tschan, Mathieu J.‐L.; Ieong, Nga Sze; Todd, Richard; Everson, Jack

2017-01-01

Abstract Poly(ortho ester)s (POEs) are well‐known for their surface‐eroding properties and hence present unique opportunities for controlled‐release and tissue‐engineering applications. Their development and wide‐spread investigation has, however, been severely limited by challenging synthetic requirements that incorporate unstable intermediates and are therefore highly irreproducible. Herein, the first catalytic method for the synthesis of POEs using air‐ and moisture‐stable vinyl acetal precursors is presented. The synthesis of a range of POE structures is demonstrated, including those that are extremely difficult to achieve by other synthetic methods. Furthermore, application of this chemistry permits efficient installation of functional groups through ortho ester linkages on an aliphatic polycarbonate. PMID:29087610

Investigation of Miniaturized Radioisotope Thermionic Power Generation for General Use

NASA Technical Reports Server (NTRS)

Duzik, Adam J.; Choi, Sang H.

2016-01-01

Radioisotope thermoelectric generators (RTGs) running off the radioisotope Pu238 are the current standard in deep space probe power supplies. While reliable, these generators are very inefficient, operating at only approx.7% efficiency. As an alternative, more efficient radioisotope thermionic emission generators (RTIGs) are being explored. Like RTGs, current RTIGs concepts use exotic materials for the emitter, limiting applicability to space and other niche applications. The high demand for long-lasting mobile power sources would be satisfied if RTIGs could be produced inexpensively. This work focuses on exposing several common materials, such as Al, stainless steel, W, Si, and Cu, to elevated temperatures under vacuum to determine the efficiency of each material as inexpensive replacements for thermoelectric materials.

Built-up index methods and their applications for urban extraction from Sentinel 2A satellite data: discussion.

PubMed

Valdiviezo-N, Juan C; Téllez-Quiñones, Alejandro; Salazar-Garibay, Adan; López-Caloca, Alejandra A

2018-01-01

Several built-up indices have been proposed in the literature in order to extract the urban sprawl from satellite data. Given their relative simplicity and easy implementation, such methods have been widely adopted for urban growth monitoring. Previous research has shown that built-up indices are sensitive to different factors related to image resolution, seasonality, and study area location. Also, most of them confuse urban surfaces with bare soil and barren land covers. By gathering the existing built-up indices, the aim of this paper is to discuss some of their advantages, difficulties, and limitations. In order to illustrate our study, we provide some application examples using Sentinel 2A data.

DBS-LC-MS/MS assay for caffeine: validation and neonatal application.

PubMed

Bruschettini, Matteo; Barco, Sebastiano; Romantsik, Olga; Risso, Francesco; Gennai, Iulian; Chinea, Benito; Ramenghi, Luca A; Tripodi, Gino; Cangemi, Giuliana

2016-09-01

DBS might be an appropriate microsampling technique for therapeutic drug monitoring of caffeine in infants. Nevertheless, its application presents several issues that still limit its use. This paper describes a validated DBS-LC-MS/MS method for caffeine. The results of the method validation showed an hematocrit dependence. In the analysis of 96 paired plasma and DBS clinical samples, caffeine levels measured in DBS were statistically significantly lower than in plasma but the observed differences were independent from hematocrit. These results clearly showed the need for extensive validation with real-life samples for DBS-based methods. DBS-LC-MS/MS can be considered to be a good alternative to traditional methods for therapeutic drug monitoring or PK studies in preterm infants.

Designing projects for motivating students towards scientific exploration: application to student mentoring

NASA Astrophysics Data System (ADS)

Awwal, Abdul A. S.

2016-09-01

Every summer in the National Ignition Facility (NIF) at Lawrence Livermore National Laboratory, students are brought in to gain interesting research and development experience. In this work, we will review some case studies of past research experiences with students inside and outside NIF, that led to successful journal and conference publications. Several of these works will be reviewed to demonstrate how problems were chosen and defined so that meaningful results could be obtained within a limited time frame. It is anticipated that success with such projects will go a long way in motivating students in their future graduate career. Projects from laser measurement, optical computing and application of matched filtering in laser beam alignment will be reviewed to demonstrate this approach.

Application of several methods for determining transfer functions and frequency response of aircraft from flight data

NASA Technical Reports Server (NTRS)

Eggleston, John M; Mathews, Charles W

1954-01-01

In the process of analyzing the longitudinal frequency-response characteristics of aircraft, information on some of the methods of analysis has been obtained by the Langley Aeronautical Laboratory of the National Advisory Committee for Aeronautics. In the investigation of these methods, the practical applications and limitations were stressed. In general, the methods considered may be classed as: (1) analysis of sinusoidal response, (2) analysis of transient response as to harmonic content through determination of the Fourier integral by manual or machine methods, and (3) analysis of the transient through the use of least-squares solutions of the coefficients of an assumed equation for either the transient time response or frequency response (sometimes referred to as curve-fitting methods). (author)

On securing wireless sensor network--novel authentication scheme against DOS attacks.

PubMed

Raja, K Nirmal; Beno, M Marsaline

2014-10-01

Wireless sensor networks are generally deployed for collecting data from various environments. Several applications specific sensor network cryptography algorithms have been proposed in research. However WSN's has many constrictions, including low computation capability, less memory, limited energy resources, vulnerability to physical capture, which enforce unique security challenges needs to make a lot of improvements. This paper presents a novel security mechanism and algorithm for wireless sensor network security and also an application of this algorithm. The proposed scheme is given to strong authentication against Denial of Service Attacks (DOS). The scheme is simulated using network simulator2 (NS2). Then this scheme is analyzed based on the network packet delivery ratio and found that throughput has improved.

Metagenomic applications in environmental monitoring and bioremediation

DOE PAGES

Techtmann, Stephen M.; Hazen, Terry C.

2016-01-01

With the rapid advances in sequencing technology, the cost of sequencing has dramatically dropped and the scale of sequencing projects has increased accordingly. This has provided the opportunity for the routine use of sequencing techniques in the monitoring of environmental microbes. While metagenomic applications have been routinely applied to better understand the ecology and diversity of microbes, their use in environmental monitoring and bioremediation is increasingly common. In this review we seek to provide an overview of some of the metagenomic techniques used in environmental systems biology, addressing their application and limitation. We will also provide several recent examples ofmore » the application of metagenomics to bioremediation. We discuss examples where microbial communities have been used to predict the presence and extent of contamination, examples of how metagenomics can be used to characterize the process of natural attenuation by unculturable microbes, as well as examples detailing the use of metagenomics to understand the impact of biostimulation on microbial communities.« less

Mind-body interventions: applications in neurology.

PubMed

Wahbeh, Helané; Elsas, Siegward-M; Oken, Barry S

2008-06-10

Half of the adults in the United States use complementary and alternative medicine with mind-body therapy being the most commonly used form. Neurology patients often turn to their physicians for insight into the effectiveness of the therapies and resources to integrate them into their care. The objective of this article is to give a clinical overview of mind-body interventions and their applications in neurology. Medline and PsychInfo were searched on mind-body therapies and neurologic disease search terms for clinical trials and reviews and published evidence was graded. Meditation, relaxation, and breathing techniques, yoga, tai chi, and qigong, hypnosis, and biofeedback are described. Mind-body therapy application to general pain, back and neck pain, carpal tunnel syndrome, headaches, fibromyalgia, multiple sclerosis, epilepsy, muscular dysfunction, stroke, aging, Parkinson disease, stroke, and attention deficit-hyperactivity disorder are reviewed. There are several conditions where the evidence for mind-body therapies is quite strong such as migraine headache. Mind-body therapies for other neurology applications have limited evidence due mostly to small clinical trials and inadequate control groups.

Hot-melt extrusion--basic principles and pharmaceutical applications.

PubMed

Lang, Bo; McGinity, James W; Williams, Robert O

2014-09-01

Originally adapted from the plastics industry, the use of hot-melt extrusion has gained favor in drug delivery applications both in academia and the pharmaceutical industry. Several commercial products made by hot-melt extrusion have been approved by the FDA, demonstrating its commercial feasibility for pharmaceutical processing. A significant number of research articles have reported on advances made regarding the pharmaceutical applications of the hot-melt extrusion processing; however, only limited articles have been focused on general principles regarding formulation and process development. This review provides an in-depth analysis and discussion of the formulation and processing aspects of hot-melt extrusion. The impact of physicochemical properties of drug substances and excipients on formulation development using a hot-melt extrusion process is discussed from a material science point of view. Hot-melt extrusion process development, scale-up, and the interplay of formulation and process attributes are also discussed. Finally, recent applications of hot-melt extrusion to a variety of dosage forms and drug substances have also been addressed.

Medium-range, objective predictions of thunderstorm location and severity for aviation

NASA Technical Reports Server (NTRS)

Wilson, G. S.; Turner, R. E.

1981-01-01

This paper presents a computerized technique for medium-range (12-48h) prediction of both the location and severity of thunderstorms utilizing atmospheric predictions from the National Meteorological Center's limited-area fine-mesh model (LFM). A regional-scale analysis scheme is first used to examine the spatial and temporal distributions of forecasted variables associated with the structure and dynamics of mesoscale systems over an area of approximately 10 to the 6th sq km. The final prediction of thunderstorm location and severity is based upon an objective combination of these regionally analyzed variables. Medium-range thunderstorm predictions are presented for the late afternoon period of April 10, 1979, the day of the Wichita Falls, Texas tornado. Conventional medium-range thunderstorm forecasts, made from observed data, are presented with the case study to demonstrate the possible application of this objective technique in improving 12-48 h thunderstorm forecasts for aviation.

Designing high-performance layered thermoelectric materials through orbital engineering

PubMed Central

Zhang, Jiawei; Song, Lirong; Madsen, Georg K. H.; Fischer, Karl F. F.; Zhang, Wenqing; Shi, Xun; Iversen, Bo B.

2016-01-01

Thermoelectric technology, which possesses potential application in recycling industrial waste heat as energy, calls for novel high-performance materials. The systematic exploration of novel thermoelectric materials with excellent electronic transport properties is severely hindered by limited insight into the underlying bonding orbitals of atomic structures. Here we propose a simple yet successful strategy to discover and design high-performance layered thermoelectric materials through minimizing the crystal field splitting energy of orbitals to realize high orbital degeneracy. The approach naturally leads to design maps for optimizing the thermoelectric power factor through forming solid solutions and biaxial strain. Using this approach, we predict a series of potential thermoelectric candidates from layered CaAl2Si2-type Zintl compounds. Several of them contain nontoxic, low-cost and earth-abundant elements. Moreover, the approach can be extended to several other non-cubic materials, thereby substantially accelerating the screening and design of new thermoelectric materials. PMID:26948043

40 CFR 445.11 - Effluent limitations attainable by the application of the best practicable control technology...

Code of Federal Regulations, 2010 CFR

2010-07-01

... application of the best practicable control technology currently available (BPT). 445.11 Section 445.11... attainable by the application of the best practicable control technology currently available (BPT). Except as... the following effluent limitations which represent the application of BPT: Effluent Limitations...

40 CFR 439.34 - Effluent limitations attainable by the application of best available technology economically...

Code of Federal Regulations, 2014 CFR

2014-07-01

... application of best available technology economically achievable (BAT). 439.34 Section 439.34 Protection of... attainable by the application of best available technology economically achievable (BAT). Except as provided... following effluent limitations representing the application of BAT: (a) The limitations are the same as...

40 CFR 437.13 - Effluent limitations attainable by the application of the best available technology economically...

Code of Federal Regulations, 2010 CFR

2010-07-01

... application of the best available technology economically achievable (BAT). 437.13 Section 437.13 Protection... attainable by the application of the best available technology economically achievable (BAT). (a) Except as... must achieve the following effluent limitations representing the application of BAT: Limitations for...

40 CFR 439.14 - Effluent limitations attainable by the application of best available technology economically...

Code of Federal Regulations, 2014 CFR

2014-07-01

... application of best available technology economically achievable (BAT). 439.14 Section 439.14 Protection of... by the application of best available technology economically achievable (BAT). (a) Except as provided... following effluent limitations representing the application of BAT: Effluent Limitations (BAT) Regulated...

40 CFR 439.14 - Effluent limitations attainable by the application of best available technology economically...

Code of Federal Regulations, 2013 CFR

2013-07-01

... application of best available technology economically achievable (BAT). 439.14 Section 439.14 Protection of... by the application of best available technology economically achievable (BAT). (a) Except as provided... following effluent limitations representing the application of BAT: Effluent Limitations (BAT) Regulated...

40 CFR 439.14 - Effluent limitations attainable by the application of best available technology economically...

Code of Federal Regulations, 2011 CFR

2011-07-01

... application of best available technology economically achievable (BAT). 439.14 Section 439.14 Protection of... application of best available technology economically achievable (BAT). (a) Except as provided in 40 CFR 125... effluent limitations representing the application of BAT: Effluent Limitations (BAT) Regulated parameter...

40 CFR 432.93 - Effluent limitations attainable by the application of the best available technology economically...

Code of Federal Regulations, 2012 CFR

2012-07-01

... application of the best available technology economically achievable (BAT). 432.93 Section 432.93 Protection... limitations attainable by the application of the best available technology economically achievable (BAT... must achieve the following effluent limitations representing the application of BAT: (a) Facilities...

40 CFR 439.34 - Effluent limitations attainable by the application of best available technology economically...

Code of Federal Regulations, 2012 CFR

2012-07-01

... application of best available technology economically achievable (BAT). 439.34 Section 439.34 Protection of... attainable by the application of best available technology economically achievable (BAT). Except as provided... following effluent limitations representing the application of BAT: (a) The limitations are the same as...

40 CFR 432.103 - Effluent limitations attainable by the application of the best available technology economically...

Code of Federal Regulations, 2012 CFR

2012-07-01

... application of the best available technology economically achievable (BAT). 432.103 Section 432.103 Protection... attainable by the application of the best available technology economically achievable (BAT). Except as... the following effluent limitations representing the application of BAT: Effluent Limitations [BAT...

40 CFR 437.13 - Effluent limitations attainable by the application of the best available technology economically...

Code of Federal Regulations, 2011 CFR

2011-07-01

... application of the best available technology economically achievable (BAT). 437.13 Section 437.13 Protection... attainable by the application of the best available technology economically achievable (BAT). (a) Except as... must achieve the following effluent limitations representing the application of BAT: Limitations for...

40 CFR 439.34 - Effluent limitations attainable by the application of best available technology economically...

Code of Federal Regulations, 2013 CFR

2013-07-01

... application of best available technology economically achievable (BAT). 439.34 Section 439.34 Protection of... attainable by the application of best available technology economically achievable (BAT). Except as provided... following effluent limitations representing the application of BAT: (a) The limitations are the same as...

40 CFR 432.93 - Effluent limitations attainable by the application of the best available technology economically...

Code of Federal Regulations, 2013 CFR

2013-07-01

... application of the best available technology economically achievable (BAT). 432.93 Section 432.93 Protection... limitations attainable by the application of the best available technology economically achievable (BAT... must achieve the following effluent limitations representing the application of BAT: (a) Facilities...

40 CFR 432.123 - Effluent limitations attainable by the application of the best available technology economically...

Code of Federal Regulations, 2010 CFR

2010-07-01

... application of the best available technology economically achievable (BAT). 432.123 Section 432.123 Protection... attainable by the application of the best available technology economically achievable (BAT). Except as... effluent limitations representing the application of BAT: Effluent Limitations [BAT] Regulatedparameter...

40 CFR 439.14 - Effluent limitations attainable by the application of best available technology economically...

Code of Federal Regulations, 2010 CFR

2010-07-01

... application of best available technology economically achievable (BAT). 439.14 Section 439.14 Protection of... application of best available technology economically achievable (BAT). (a) Except as provided in 40 CFR 125... effluent limitations representing the application of BAT: Effluent Limitations (BAT) Regulated parameter...

40 CFR 439.14 - Effluent limitations attainable by the application of best available technology economically...

Code of Federal Regulations, 2012 CFR

2012-07-01

... application of best available technology economically achievable (BAT). 439.14 Section 439.14 Protection of... by the application of best available technology economically achievable (BAT). (a) Except as provided... following effluent limitations representing the application of BAT: Effluent Limitations (BAT) Regulated...

40 CFR 432.103 - Effluent limitations attainable by the application of the best available technology economically...

Code of Federal Regulations, 2014 CFR

2014-07-01

... application of the best available technology economically achievable (BAT). 432.103 Section 432.103 Protection... attainable by the application of the best available technology economically achievable (BAT). Except as... the following effluent limitations representing the application of BAT: Effluent Limitations [BAT...

40 CFR 437.23 - Effluent limitations attainable by the application of the best available technology economically...

Code of Federal Regulations, 2011 CFR

2011-07-01

... application of the best available technology economically achievable (BAT). 437.23 Section 437.23 Protection... attainable by the application of the best available technology economically achievable (BAT). Except as... must achieve the following effluent limitations by the application of BAT: Limitations for arsenic...

40 CFR 451.22 - Effluent limitations attainable by the application of the best available technology economically...

Code of Federal Regulations, 2011 CFR

2011-07-01

... application of the best available technology economically achievable (BAT). 451.22 Section 451.22 Protection... attainable by the application of the best available technology economically achievable (BAT). Except as... the following effluent limitations representing the application of BAT: The limitations are the same...

40 CFR 432.103 - Effluent limitations attainable by the application of the best available technology economically...

Code of Federal Regulations, 2013 CFR

2013-07-01

... application of the best available technology economically achievable (BAT). 432.103 Section 432.103 Protection... attainable by the application of the best available technology economically achievable (BAT). Except as... the following effluent limitations representing the application of BAT: Effluent Limitations [BAT...

40 CFR 432.103 - Effluent limitations attainable by the application of the best available technology economically...

Code of Federal Regulations, 2011 CFR

2011-07-01

... application of the best available technology economically achievable (BAT). 432.103 Section 432.103 Protection... application of the best available technology economically achievable (BAT). Except as provided by 40 CFR 125... effluent limitations representing the application of BAT: Effluent Limitations [BAT] Regulatedparameter...

40 CFR 432.123 - Effluent limitations attainable by the application of the best available technology economically...

Code of Federal Regulations, 2011 CFR

2011-07-01

... application of the best available technology economically achievable (BAT). 432.123 Section 432.123 Protection... attainable by the application of the best available technology economically achievable (BAT). Except as... effluent limitations representing the application of BAT: Effluent Limitations [BAT] Regulatedparameter...

40 CFR 432.93 - Effluent limitations attainable by the application of the best available technology economically...

Code of Federal Regulations, 2014 CFR

2014-07-01

... application of the best available technology economically achievable (BAT). 432.93 Section 432.93 Protection... limitations attainable by the application of the best available technology economically achievable (BAT... must achieve the following effluent limitations representing the application of BAT: (a) Facilities...

40 CFR 451.22 - Effluent limitations attainable by the application of the best available technology economically...

Code of Federal Regulations, 2010 CFR

2010-07-01

... application of the best available technology economically achievable (BAT). 451.22 Section 451.22 Protection... attainable by the application of the best available technology economically achievable (BAT). Except as... the following effluent limitations representing the application of BAT: The limitations are the same...

40 CFR 437.23 - Effluent limitations attainable by the application of the best available technology economically...

Code of Federal Regulations, 2010 CFR

2010-07-01

... application of the best available technology economically achievable (BAT). 437.23 Section 437.23 Protection... attainable by the application of the best available technology economically achievable (BAT). Except as... must achieve the following effluent limitations by the application of BAT: Limitations for arsenic...

40 CFR 432.103 - Effluent limitations attainable by the application of the best available technology economically...

Code of Federal Regulations, 2010 CFR

2010-07-01

... application of the best available technology economically achievable (BAT). 432.103 Section 432.103 Protection... application of the best available technology economically achievable (BAT). Except as provided by 40 CFR 125... effluent limitations representing the application of BAT: Effluent Limitations [BAT] Regulatedparameter...

Navy Applications of High-Frequency Acoustics

NASA Astrophysics Data System (ADS)

Cox, Henry

2004-11-01

Although the emphasis in underwater acoustics for the last few decades has been in low-frequency acoustics, motivated by long range detection of submarines, there has been a continuing use of high-frequency acoustics in traditional specialized applications such as bottom mapping, mine hunting, torpedo homing and under ice navigation. The attractive characteristics of high-frequency sonar, high spatial resolution, wide bandwidth, small size and relatively low cost must be balanced against the severe range limitation imposed by attenuation that increases approximately as frequency-squared. Many commercial applications of acoustics are ideally served by high-frequency active systems. The small size and low cost, coupled with the revolution in small powerful signal processing hardware has led to the consideration of more sophisticated systems. Driven by commercial applications, there are currently available several commercial-off-the-shelf products including acoustic modems for underwater communication, multi-beam fathometers, side scan sonars for bottom mapping, and even synthetic aperture side scan sonar. Much of the work in high frequency sonar today continues to be focused on specialized applications in which the application is emphasized over the underlying acoustics. Today's vision for the Navy of the future involves Autonomous Undersea Vehicles (AUVs) and off-board ASW sensors. High-frequency acoustics will play a central role in the fulfillment of this vision as a means of communication and as a sensor. The acoustic communication problems for moving AUVs and deep sensors are discussed. Explicit relationships are derived between the communication theoretic description of channel parameters in terms of time and Doppler spreads and ocean acoustic parameters, group velocities, phase velocities and horizontal wavenumbers. Finally the application of synthetic aperture sonar to the mine hunting problems is described.