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1

Advanced Techniques for Constrained Internal Coordinate Molecular Dynamics  

PubMed Central

Internal coordinate molecular dynamics (ICMD) methods provide a more natural description of a protein by using bond, angle and torsional coordinates instead of a Cartesian coordinate representation. Freezing high frequency bonds and angles in the ICMD model gives rise to constrained ICMD (CICMD) models. There are several theoretical aspects that need to be developed in order to make the CICMD method robust and widely usable. In this paper we have designed a new framework for 1) initializing velocities for non-independent CICMD coordinates, 2) efficient computation of center of mass velocity during CICMD simulations, 3) using advanced integrators such as Runge-Kutta, Lobatto and adaptive CVODE for CICMD simulations, and 4) cancelling out the “flying ice cube effect” that sometimes arises in Nosé-Hoover dynamics. The Generalized Newton-Euler Inverse Mass Operator (GNEIMO) method is an implementation of a CICMD method that we have developed to study protein dynamics. GNEIMO allows for a hierarchy of coarse-grained simulation models based on the ability to rigidly constrain any group of atoms. In this paper, we perform tests on the Lobatto and Runge-Kutta integrators to determine optimal simulation parameters. We also implement an adaptive coarse graining tool using the GNEIMO Python interface. This tool enables the secondary structure-guided “freezing and thawing” of degrees of freedom in the molecule on the fly during MD simulations, and is shown to fold four proteins to their native topologies. With these advancements we envision the use of the GNEIMO method in protein structure prediction, structure refinement, and in studying domain motion. PMID:23345138

Wagner, Jeffrey R.; Balaraman, Gouthaman S.; Niesen, Michiel J. M.; Larsen, Adrien B.; Jain, Abhinandan; Vaidehi, Nagarajan

2013-01-01

2

Advanced Molecular Biology Techniques Laboratory: A Research-Integrated Approach using Drosophila melanogaster  

NSDL National Science Digital Library

This advanced molecular biology laboratory course, which uses a project approach to learning and incorporates an independent research component, was designed to enhance the preparation of students for careers in research, biotechnology and science education and to increase knowledge retention and integration of concepts among upper level biology majors. The students use enhancer trap techniques in Drosophila melanogaster to work on two related projects in a single semester. One project has been carefully worked out to proceed through a set of experiments that take the students from a behavior mutant (flightless), to a cloned and sequenced gene (gene for muscle myosin heavy chain protein), and finally to a study of the protein. This part of the laboratory experience exposes the students to a wide array of molecular biology methodologies and instrumentation commonly used in biotechnology and molecular biology laboratories and demonstrates the logical progression of a research project. The research project starts with mutants which are already available but for which the mutated gene has not yet been discovered. The students will use the techniques that they have learned to clone and sequence the gene and to begin to study the protein. The integration of a research component into this laboratory course will increase students' mastery of the principles of scientific inquiry and their ability to draw on their accumulated knowledge to solve research problems. This course will give students who plan career in research or biotechnology practical experience that mimics the realities of the laboratory setting. It will provide students who are planning careers in education with the background necessary to bring modern technology and inquiry-based learning into the classroom.

Hofstra University (Hofstra University)

2012-01-06

3

Advanced techniques in molecular genetics and its implications on genetic testing and screening in the Arabian Peninsula.  

PubMed

Molecular diagnosis of human disorders is referred to as the detection of the various pathogenic mutations in DNA and/or RNA samples in order to facilitate detection, diagnosis, sub-classification, prognosis, and monitoring response to therapy. The use of molecular biology techniques to expand scientific knowledge of the natural history of diseases, identify people who are at risk for acquiring specific diseases, and diagnose human diseases at the nucleic acid level. Molecular diagnostics combines laboratory medicine with the knowledge and technology of molecular genetics and has been enormously revolutionized over the last decades, benefiting from the discoveries in the field of molecular biology. This review will discuss in details the recent advances in molecular diagnostics and how the Arabian Peninsula can benefit from those techniques knowing for a fact the high percentages of consanguineous marriages and the tribal nature of marriages which resulted in high incidence of genetic diseases. PMID:24145931

Abu-Amero, Khaled K; Kondkar, Altaf A

2013-10-01

4

Two Photon Excitation of Molecular Iodine. An Advanced Laser Technique for the Undergraduate Physical Chemistry Lab  

NASA Astrophysics Data System (ADS)

The iodine molecule is routinely studied in the undergraduate physical chemistry lab and provides practical experiments for topics such as chemical kinetics, phase equilibrium, and electronic molecular structure. In an effort to improve and modernize the physical chemistry lab, many of these experiments now incorporate the use of lasers; for instance, a laser can quite easily be used as the light source for iodine emission and fluorescence quenching experiments. To introduce the use of multiple-laser techniques, and to further the study of iodine in the undergraduate teaching lab, we have developed a double resonance method for accessing the ion-pair states of iodine using a relatively inexpensive nitrogen-pumped dye laser. Iodine is pumped to the B state with the dye laser, followed by excitation to the E and f states with a small portion of the nitrogen beam reflected off the parent beam by a quartz window. The strongest emission to the B state occurs from the f state, and progressions of up to 30 vibrational bands are observed. By varying the energy of the dye laser, we are able to pump vibrational levels of the f state from v=0 up to at least v=17. Analysis of our spectra is complicated by the presence of hot bands and by the relatively large bandwidth of our laser. Even so, we are able to adequately assign most spectral bands and their intensities with the aid of Franck-Condon calculations.

Lynch, W. Bryan; Gootee, Megan J.; Chavez, Marc P.

2009-06-01

5

Gliomas: advances in molecular analysis and characterization  

Microsoft Academic Search

BackgroundGliomas represent the most common primary brain tumor. Despite recent advances in diagnostic imaging, neurosurgical technique, radiation therapy, and chemotherapy, significant advances in accurate prognosis and improved survival have not been achieved. Nevertheless, new developments in molecular biology could have potential impact on the clinical management of patients with these brain tumors. This review will describe the technological advances being

Christine R. Boudreau; Isaac Yang; Linda M. Liau

2005-01-01

6

Recent advances in molecular lithography  

NASA Astrophysics Data System (ADS)

The precise placement of molecular and nanoparticle species at predetermined locations on a substrate surface remains a current challenge. Some barriers are particularly relevant to soft matter such as biomolecules. The advent of DNA Origami, invented by Rothemund, provides partial solutions to some challenges while raising new challenges. In this paper, two particular levels of molecular placement will be discussed, associating large DNA based molecular nanostructures with traditional lithographic nanostructures and the association of molecular scale species with particular locations within large Origami structures. Typical plasmid based DNA Origami nanostructures are approximately 100 nm in diameter. This size scale closely matches that of gold nanoscale structures which are readily produced using ebeam and other lithographic techniques. The strategy for associating large DNA based nanostructures with these lithographic structures employs the placement of thiol terminated DNA molecules within the molecular assembly, positioned to allow tethering of the biomolecular nanostructure to the substrate through gold-thiol bonds. Although a number of soft chemistry mechanisms can be employed to associate DNA molecules with substrates, the use of the origami constructs as substrates suggests that single stranded DNA provides the optimum attachment strategy. A solid state asymmetric PCR process for ssDNA fabrication is therefore described and demonstrated. Structures generated with the three tiered attachment strategy described here are amenable to characterization and assembly verification using AFM and NSOM. While a complete convergence of top down and bottom up approaches cannot be claimed, it is clear that the practice and methods of molecular lithography are rapidly advancing.

Norton, Michael; Rahman, Mashiur; Day, B. Scott; Huffman, Chad; Cao, Huan; Neff, David; Butts, Heather; Gin, Aaron

2007-09-01

7

Advanced Optical Measurement Techniques  

NASA Technical Reports Server (NTRS)

This research analyzes four areas: (1) Improved Techniques for Optical Measurement; (2) KC-135 Low Gravity Simulation Flight Preparation; (3) In-Line Holographic Microscopy; and (4) Holographic Optical Schlieren System (HOSS). The first task provides for laboratory breadboarding of advanced optical measurement techniques which appear promising for use in Material Processing System (MPS) flight experiments. A laboratory schlieren system has been constructed which simulates a similar optical system on the Fluids Experiment System (FES) which is to be flown on Spacelab 3. The second task allows improved optical systems and breadboards to be built for experiments and hardware tests on the KC-135 aircraft. A new, more stable Mach-Zehnder interferometer has been developed and components have been ordered. The third task is concerned with improvements on the optical system being used to study immiscible fluids. Experiments studying the dynamics of nucleation and the separation of immiscible fluids have been conducted. The four task involves building breadboard reconstruction systems for holograms taken in the HOSS. The HOSS is an early prototype of the Fluids Experiments System (FES) which is scheduled to fly on Spacelab 3.

Owen, R. B.; Johnston, M. H.; Witherow, W. K.

1985-01-01

8

Advanced Coating Removal Techniques  

NASA Technical Reports Server (NTRS)

An important step in the repair and protection against corrosion damage is the safe removal of the oxidation and protective coatings without further damaging the integrity of the substrate. Two such methods that are proving to be safe and effective in this task are liquid nitrogen and laser removal operations. Laser technology used for the removal of protective coatings is currently being researched and implemented in various areas of the aerospace industry. Delivering thousands of focused energy pulses, the laser ablates the coating surface by heating and dissolving the material applied to the substrate. The metal substrate will reflect the laser and redirect the energy to any remaining protective coating, thus preventing any collateral damage the substrate may suffer throughout the process. Liquid nitrogen jets are comparable to blasting with an ultra high-pressure water jet but without the residual liquid that requires collection and removal .As the liquid nitrogen reaches the surface it is transformed into gaseous nitrogen and reenters the atmosphere without any contamination to surrounding hardware. These innovative technologies simplify corrosion repair by eliminating hazardous chemicals and repetitive manual labor from the coating removal process. One very significant advantage is the reduction of particulate contamination exposure to personnel. With the removal of coatings adjacent to sensitive flight hardware, a benefit of each technique for the space program is that no contamination such as beads, water, or sanding residue is left behind when the job is finished. One primary concern is the safe removal of coatings from thin aluminum honeycomb face sheet. NASA recently conducted thermal testing on liquid nitrogen systems and found that no damage occurred on 1/6", aluminum substrates. Wright Patterson Air Force Base in conjunction with Boeing and NASA is currently testing the laser remOval technique for process qualification. Other applications of liquid nitrogen operations include cutting of both soft and hard materials. While the laser will not cut materials, it can be used to roughen surfaces and to remove other materials from the substrate including oil, grease, and mold. The space program can benefit from several of these applications with the need for precise removal of coatings and other organic compounds in areas adjacent to sensitive space flight hardware. Significant advantages are evident when comparing liquid nitrogen and laser removal operations over current techniques of media blasting and sanding.

Seibert, Jon

2006-01-01

9

Techniques for Molecular Imaging Probe Design  

PubMed Central

Molecular imaging allows clinicians to visualize disease specific molecules, thereby providing relevant information in the diagnosis and treatment of patients. With advances in genomics and proteomics and underlying mechanisms of disease pathology, the number of targets identified has significantly outpaced the number of developed molecular imaging probes. There has been a concerted effort to bridge this gap with multidisciplinary efforts in chemistry, proteomics, physics, material science, and biology; all essential to progress in molecular imaging probe development. In this review, we will discuss target selection, screening techniques and probe optimization with the aim of developing clinically relevant molecularly targeted imaging agents. PMID:22201532

Reynolds, Fred; Kelly, Kimberly A.

2011-01-01

10

Advanced Bonding\\/Joining Techniques  

Microsoft Academic Search

\\u000a In this chapter, three advanced bonding\\/joining techniques, adhesive bonding, direct bonding, and lead-free soldering, are\\u000a presented. For each technique, we first review the bonding principles and applications in electronic industries, followed\\u000a by novel bonding materials and processes.\\u000a \\u000a \\u000a For adhesive bonding, four popular adhesives, epoxy resins, silicon resins, polymides, and acrylics, are reviewed. Two new\\u000a adhesives, liquid crystal polymer (LCP) and

Chin C. Lee; Pin J. Wang; Jong S. Kim

11

Advanced techniques in GEO 600  

NASA Astrophysics Data System (ADS)

For almost 20 years, advanced techniques have been developed and tested at the GEO 600 laser-interferometric gravitational wave detector. Many of these innovations have improved the sensitivity of GEO 600 and could be shown to be consistent with stable and reliable operation of gravitational wave detectors. We review the performance of these techniques and show how they have influenced the upgrades of other detectors worldwide. In the second half of the paper, we consider how GEO 600 continues to pioneer new techniques for future gravitational wave detectors. We describe some of the new methods in detail and present new results on how they improve the sensitivity and/or the stability of GEO 600 and possibly of future detectors.

Affeldt, C.; Danzmann, K.; Dooley, K. L.; Grote, H.; Hewitson, M.; Hild, S.; Hough, J.; Leong, J.; Lück, H.; Prijatelj, M.; Rowan, S.; Rüdiger, A.; Schilling, R.; Schnabel, R.; Schreiber, E.; Sorazu, B.; Strain, K. A.; Vahlbruch, H.; Willke, B.; Winkler, W.; Wittel, H.

2014-11-01

12

LHC Olympics: Advanced Analysis Techniques  

NASA Astrophysics Data System (ADS)

The LHC Olympics is a series of workshop aimed at encouraging theorists and experimentalists to prepare for the soon-to-be-online Large Hadron Collider in Geneva, Switzerland. One aspect of the LHC Olympics program consists of the study of simulated data sets which represent various possible new physics signals as they would be seen in LHC detectors. Through this exercise, LHC Olympians learn the phenomenology of possible new physics models and gain experience in analyzing LHC data. Additionally, the LHC Olympics encourages discussion between theorists and experimentalists, and through this collaboration new techniques could be developed. The University of Washington LHC Olympics group consists of several first-year graduate and senior undergraduate students, in both theoretical and experimental particle physics. Presented here is a discussion of some of the more advanced techniques used and the recent results of one such LHC Olympics study.

Armour, Kyle; Larkoski, Andrew; Gray, Amanda; Ventura, Dan; Walsh, Jon; Schabinger, Rob

2006-05-01

13

Advances in multimodality molecular imaging  

PubMed Central

Multimodality molecular imaging using high resolution positron emission tomography (PET) combined with other modalities is now playing a pivotal role in basic and clinical research. The introduction of combined PET/CT systems in clinical setting has revolutionized the practice of diagnostic imaging. The complementarity between the intrinsically aligned anatomic (CT) and functional or metabolic (PET) information provided in a “one-stop shop” and the possibility to use CT images for attenuation correction of the PET data has been the driving force behind the success of this technology. On the other hand, combining PET with Magnetic Resonance Imaging (MRI) in a single gantry is technically more challenging owing to the strong magnetic fields. Nevertheless, significant progress has been made resulting in the design of few preclinical PET systems and one human prototype dedicated for simultaneous PET/MR brain imaging. This paper discusses recent advances in PET instrumentation and the advantages and challenges of multimodality imaging systems. Future opportunities and the challenges facing the adoption of multimodality imaging instrumentation will also be addressed. PMID:20098557

Zaidi, Habib; Prasad, Rameshwar

2009-01-01

14

Use of molecular techniques in bioremediation.  

PubMed

In a practical sense, biotechnology is concerned with the production of commercial products generated by biological processes. More formally, biotechnology may be defined as "the application of scientific and engineering principles to the processing of material by biological agents to provide goods and services" (Cantor, 2000). From a historical perspective, biotechnology dates back to the time when yeast was first used for beer or wine fermentation, and bacteria were used to make yogurt. In 1972, the birth of recombinant DNA technology moved biotechnology to new heights and led to the establishment of a new industry. Progress in biotechnology has been truly remarkable. Within four years of the discovery of recombinant DNA technology, genetically modified organisms (GMOs) were making human insulin, interferon, and human growth hormone. Now, recombinant DNA technology and its products--GMOs are widely used in environmental biotechnology (Glick and Pasternak, 1988; Cowan, 2000). Bioremediation is one of the most rapidly growing areas of environmental biotechnology. Use of bioremediation for environmental clean up is popular due to low costs and its public acceptability. Indeed, bioremediation stands to benefit greatly and advance even more rapidly with the adoption of molecular techniques developed originally for other areas of biotechnology. The 1990s was the decade of molecular microbial ecology (time of using molecular techniques in environmental biotechnology). Adoption of these molecular techniques made scientists realize that microbial populations in the natural environments are much more diverse than previously thought using traditional culture methods. Using molecular ecological methods, such as direct DNA isolation from environmental samples, denaturing gradient gel electrophoresis (DGGE), PCR methods, nucleic acid hybridization etc., we can now study microbial consortia relevant to pollutant degradation in the environment. These techniques promise to provide a better understanding and better control of environmental biotechnology processes, thus enabling more cost effective and efficient bioremediation of our toxic waste and contaminated environments. PMID:11930989

P?aza, G; Ulfig, K; Hazen, T C; Brigmon, R L

2001-01-01

15

Recent advances in molecular lithography  

Microsoft Academic Search

The precise placement of molecular and nanoparticle species at predetermined locations on a substrate surface remains a current challenge. Some barriers are particularly relevant to soft matter such as biomolecules. The advent of DNA Origami, invented by Rothemund, provides partial solutions to some challenges while raising new challenges. In this paper, two particular levels of molecular placement will be discussed,

Michael Norton; Mashiur Rahman; B. Scott Day; Chad Huffman; Huan Cao; David Neff; Heather Butts; Aaron Gin

2007-01-01

16

Stitching Techniques Advance Optics Manufacturing  

NASA Technical Reports Server (NTRS)

Because NASA depends on the fabrication and testing of large, high-quality aspheric (nonspherical) optics for applications like the James Webb Space Telescope, it sought an improved method for measuring large aspheres. Through Small Business Innovation Research (SBIR) awards from Goddard Space Flight Center, QED Technologies, of Rochester, New York, upgraded and enhanced its stitching technology for aspheres. QED developed the SSI-A, which earned the company an R&D 100 award, and also developed a breakthrough machine tool called the aspheric stitching interferometer. The equipment is applied to advanced optics in telescopes, microscopes, cameras, medical scopes, binoculars, and photolithography."

2010-01-01

17

Ultrasonic Tests. Pt. 2. Advanced Techniques.  

National Technical Information Service (NTIS)

After a basic treatment of ultrasonic wave propagation, of the state-of-the-art methods and the technical background in the preceeding part, advanced ultrasonic NDT techniques are presented here. The discussion of new development includes - manipulation s...

K. Goebbels

1980-01-01

18

Recent Advancements in Titan Balloon Techniques  

NASA Astrophysics Data System (ADS)

Suggestions for the use of balloons to explore Saturn's icy moon Titan have been proposed for more than 40 years. Many alternative mission concepts [1], [2], [4], [5] have been developed since that time, catalyzed by scientific discoveries resulting from the Voyager 1 flyby in 1980 and the Cassini- Huygens mission that arrived in 2004. The results from Cassini-Huygens, in particular, revealed Titan to be a complex and fascinating world with diverse topographical features and a methane-based hydrological cycle. The Huygens probe [3] demonstrated excellent visibility below a 10 km altitude with its high resolution images and measured low wind speeds at the surface (< 1-2 m/s). The motivation to return to Titan has intensified in the wake of these results and the increasing priority of related scientific questions. Because of the uniquely dense, high molecular weight atmosphere, very small diurnal temperature variations and low gravity, it is widely recognized that a buoyant vehicle could provide an unparalleled means of in situ exploration on a global scale. This oral presentation provides a summary of recent advancements in Titan balloon techniques that someday will enable a return to Titan on a grand scale.

Reh, K.; Hall, J.; Vargas, A.; Colonius, T.; Dieudonne, W.; Coustenis, A.; Lunine, J.; Deramecourt, A.

2011-10-01

19

Recent Advancements in Titan Balloon Techniques  

NASA Astrophysics Data System (ADS)

Suggestions for the use of balloons to explore Saturn's icy moon Titan have been proposed for more than 40 years. Many alternative mission concepts [1], [2], [4], [5] have been developed since that time, catalyzed by scientific discoveries resulting from the Voyager 1 flyby in 1980 and the Cassini- Huygens mission that arrived in 2004. The results from Cassini-Huygens, in particular, revealed Titan to be a complex and fascinating world with diverse topographical features and a methane-based hydrological cycle. The Huygens probe [3] demonstrated excellent visibility below a 10 km altitude with its high resolution images and measured low wind speeds at the surface (< 1-2 m/s). The motivation to return to Titan has intensified in the wake of these results and the increasing priority of related scientific questions. Because of the uniquely dense, high molecular weight atmosphere, very small diurnal temperature variations and low gravity, it is widely recognized that a buoyant vehicle could provide an unparalleled means of in situ exploration on a global scale. This poster provides a summary of recent advancements in Titan balloon techniques that someday will enable a return to Titan on a grand scale.

Reh, K.; Hall, J.; Vargas, A.; Colonius, T.; Dieudonne, W.; Coustenis, A.; Lunine, J.; Deramecourt, A.

2011-10-01

20

Modern molecular cytogenetic techniques in genetic diagnostics  

Microsoft Academic Search

During the past decade, fluorescence in situ hybridization (FISH) has become an important complementing application in genetic diagnostics. The use of variable FISH techniques enhances the thorough interpretation of numerical and complex chromosome aberrations, bridging the gap between conventional chromosome banding analysis and molecular genetic DNA studies. This review gives a brief overview of the different molecular cytogenetic FISH techniques

Holger Tönnies

2002-01-01

21

Advanced Techniques Using Contrast Media in Neuroimaging  

PubMed Central

This article presents an overview of advanced MRI techniques using contrast media in neuroimaging, focusing on T2*-weighted dynamic susceptibility contrast MR imaging (DSC-MRI) and T1-weighted dynamic contrast-enhanced MR imaging (DCE-MRI). Image acquisition and data processing methods as well as their clinical application in brain tumors, stroke, dementia and multiple sclerosis are discussed. PMID:23088946

Ferre, Jean-Christophe; Shiroishi, Mark S.; Law, Meng

2012-01-01

22

Recent advancement of turbulent flow measurement techniques  

NASA Technical Reports Server (NTRS)

Advancements of the fluctuating density gradient cross beam laser Schlieren technique, the fluctuating line-reversal temperature measurement and the development of the two-dimensional drag-sensing probe to a three-dimensional drag-sensing probe are discussed. The three-dimensionality of the instantaneous momentum vector can shed some light on the nature of turbulence especially with swirling flow. All three measured fluctuating quantities (density, temperature, and momentum) can provide valuable information for theoreticians.

Battle, T.; Wang, P.; Cheng, D. Y.

1974-01-01

23

Robust Iris Recognition Using Advanced Correlation Techniques  

Microsoft Academic Search

\\u000a The iris is considered one of the most reliable and stable biometrics as it is believed to not change significantly during\\u000a a person’s lifetime. Standard techniques for iris recognition, popularized by Daugman, apply Gabor wavelet analysis for feature\\u000a extraction. In this paper, we consider an alternative method for iris recognition, the use of advanced distortion-tolerant\\u000a correlation filters for robust pattern

Jason Thornton; Marios Savvides; B. V. K. Vijaya Kumar

2005-01-01

24

Advanced Techniques for MRI of Atherosclerotic Plaque  

PubMed Central

This review examines the state of the art in vessel wall imaging by MRI with an emphasis on the biomechanical assessment of atherosclerotic plaque. Three areas of advanced techniques are discussed. First, alternative contrast mechanisms, including susceptibility, magnetization transfer, diffusion and perfusion, are presented in regards to how they facilitate accurate determination of plaque constituents underlying biomechanics. Second, imaging technologies, including hardware and sequences, are reviewed in regards to how they provide the resolution and SNR necessary for determining plaque structure. Finally, techniques for combining MRI data into an overall assessment of plaque biomechanical properties, including wall shear stress and internal plaque strain, are presented. The paper closes with a discussion of the extent to which these techniques have been applied to different arteries commonly targeted by vessel wall MRI. PMID:20805732

Kerwin, William S.; Canton, Gador

2011-01-01

25

[Molecular taxonomy techniques used for yeast identification].  

PubMed

Due to the major impact of yeasts in human life based on the existence of pathogen yeast species and of species with biotechnological abilities, in the last few years new molecular techniques are performed for an accurate identification of natural isolates. Our study is aimed to review some of these techniques such as electrokariotyping by PFGE (Pulsed Field Gel Electrophoresis), estimation of the molar percentage of guanine and cytosine, the applications of PCR reaction in yeast identification using RAPD (Random amplified polymorphic DNA), UP-PCR (Universally Primed Polymerase Chain Reaction), MLST (Multilocus sequence typing) techniques, mtDNA and rDNA homology studies. Such molecular techniques complete the phenotypical characterization based on classical taxonomical tests allowing thus the polyphasic identification of the microorganisms. PMID:16938931

Ghindea, Raluca; Csutak, Ortansa; Stoica, Ileana; Ionescu, Robertina; Soare, Simona; Pelinescu, Diana; Nohit, Ana-Maria; Creang?, Oana; Vassu, Tatiana

2004-01-01

26

Advanced AE Techniques in Composite Materials Research  

NASA Technical Reports Server (NTRS)

Advanced, waveform based acoustic emission (AE) techniques have been successfully used to evaluate damage mechanisms in laboratory testing of composite coupons. An example is presented in which the initiation of transverse matrix cracking was monitored. In these tests, broad band, high fidelity acoustic sensors were used to detect signals which were then digitized and stored for analysis. Analysis techniques were based on plate mode wave propagation characteristics. This approach, more recently referred to as Modal AE, provides an enhanced capability to discriminate and eliminate noise signals from those generated by damage mechanisms. This technique also allows much more precise source location than conventional, threshold crossing arrival time determination techniques. To apply Modal AE concepts to the interpretation of AE on larger composite specimens or structures, the effects of modal wave propagation over larger distances and through structural complexities must be well characterized and understood. To demonstrate these effects, measurements of the far field, peak amplitude attenuation of the extensional and flexural plate mode components of broad band simulated AE signals in large composite panels are discussed. These measurements demonstrated that the flexural mode attenuation is dominated by dispersion effects. Thus, it is significantly affected by the thickness of the composite plate. Furthermore, the flexural mode attenuation can be significantly larger than that of the extensional mode even though its peak amplitude consists of much lower frequency components.

Prosser, William H.

1996-01-01

27

Molecular imaging: the key to advancing cardiac stem cell therapy.  

PubMed

Cardiac stem cell therapy continues to hold promise for the treatment of ischemic heart disease despite the fact that early promising pre-clinical findings have yet to be translated into consistent clinical success. The latest human studies have collectively identified a pressing need to better understand stem cell behavior in humans and called for more incorporation of noninvasive imaging techniques into the design and evaluation of human stem cell therapy trials. This review discusses the various molecular imaging techniques validated to date for studying stem cells in living subjects, with a particular emphasis on their utilities in assessing the acute retention and the long-term survival of transplanted stem cells. These imaging techniques will be essential for advancing cardiac stem cell therapy by providing the means to both guide ongoing optimization and predict treatment response in humans. PMID:23561794

Chen, Ian Y; Wu, Joseph C

2013-08-01

28

Molecular targeted therapy for advanced gastric cancer  

PubMed Central

Although medical treatment has been shown to improve quality of life and prolong survival, no significant progress has been made in the treatment of advanced gastric cancer (AGC) within the last two decades. Thus, the optimum standard first-line chemotherapy regimen for AGC remains debatable, and most responses to chemotherapy are partial and of short duration; the median survival is approximately 7 to 11 months, and survival at 2 years is exceptionally > 10%. Recently, remarkable progress in tumor biology has led to the development of new agents that target critical aspects of oncogenic pathways. For AGC, many molecular targeting agents have been evaluated in international randomized studies, and trastuzumab, an anti-HER-2 monoclonal antibody, has shown antitumor activity against HER-2-positive AGC. However, this benefit is limited to only ~20% of patients with AGC (patients with HER-2-positive AGC). Therefore, there remains a critical need for both the development of more effective agents and the identification of molecular predictive and prognostic markers to select those patients who will benefit most from specific chemotherapeutic regimens and targeted therapies. PMID:23525404

2013-01-01

29

Advanced techniques in current signature analysis  

NASA Astrophysics Data System (ADS)

In general, both ac and dc motors can be characterized as weakly nonlinear systems, in which both linear and nonlinear effects occur simultaneously. Fortunately, the nonlinearities are generally well behaved and understood and can be handled via several standard mathematical techniques already well developed in the systems modeling area; examples are piecewise linear approximations and Volterra series representations. Field measurements of numerous motors and motor-driven systems confirm the rather complex nature of motor current spectra and illustrate both linear and nonlinear effects (including line harmonics and modulation components). Although previous current signature analysis (CSA) work at Oak Ridge and other sites has principally focused on the modulation mechanisms and detection methods (AM, PM, and FM), more recent studies have been conducted on linear spectral components (those appearing in the electric current at their actual frequencies and not as modulation sidebands). For example, large axial-flow compressors (approximately 3300 hp) in the US gaseous diffusion uranium enrichment plants exhibit running-speed (approximately 20 Hz) and high-frequency vibrational information (greater than 1 kHz) in their motor current spectra. Several signal-processing techniques developed to facilitate analysis of these components, including specialized filtering schemes, are presented. Finally, concepts for the designs of advanced digitally based CSA units are offered, which should serve to foster the development of much more computationally capable 'smart' CSA instrumentation in the next several years.

Smith, S. F.; Castleberry, K. N.

1992-02-01

30

Advances and applications of molecular cloning in clinical microbiology.  

PubMed

Molecular cloning is based on isolation of a DNA sequence of interest to obtain multiple copies of it in vitro. Application of this technique has become an increasingly important tool in clinical microbiology due to its simplicity, cost effectiveness, rapidity, and reliability. This review entails the recent advances in molecular cloning and its application in the clinical microbiology in the context of polymicrobial infections, recombinant antigens, recombinant vaccines, diagnostic probes, antimicrobial peptides, and recombinant cytokines. Culture-based methods in polymicrobial infection have many limitation, which has been overcome by cloning techniques and provide gold standard technique. Recombinant antigens produced by cloning technique are now being used for screening of HIV, HCV, HBV, CMV, Treponema pallidum, and other clinical infectious agents. Recombinant vaccines for hepatitis B, cholera, influenza A, and other diseases also use recombinant antigens which have replaced the use of live vaccines and thus reduce the risk for adverse effects. Gene probes developed by gene cloning have many applications including in early diagnosis of hereditary diseases, forensic investigations, and routine diagnosis. Industrial application of this technology produces new antibiotics in the form of antimicrobial peptides and recombinant cytokines that can be used as therapeutic agents. PMID:25023463

Sharma, Kamal; Mishra, Ajay Kumar; Mehraj, Vikram; Duraisamy, Ganesh Selvaraj

2014-01-01

31

Molecular genetic diagnostic techniques in choroideremia  

PubMed Central

Purpose To optimize and streamline molecular genetics techniques in diagnosing choroideremia (CHM). Methods PCR primers were designed for exons 3, 4, 5, 6, 7, 8, 9, 10, 11, 12, and 15 of the CHM gene. Each PCR protocol was optimized so that all exons could be amplified with the same component ratio and PCR conditions. Sense and antisense primers were tested for their ability to be used as sequencing primers. Fibroblast cells were cultured, and an immunoblot analysis was performed to detect the presence or absence of Rab escort protein 1 (REP-1) in a suspected CHM patient sample when no mutation was detected with sequencing. Multiplex ligation-dependent probe amplification (MLPA) of the CHM gene was performed and used to detect deletions and duplications in affected males and female carriers. RNA analysis using cDNA was used to detect the presence or absence of the CHM transcript and to search for splice defects. Results The newly designed PCR primers allow for more efficient PCR preparation and sequencing to detect point mutations in affected males and female carriers. Immunoblot successfully detects the absence of REP-1 in a CHM patient. MLPA identifies deletions and duplications spanning multiple exons in the CHM gene. RNA analysis aids in detecting splice variants. Conclusions The development of new molecular biology techniques and ongoing optimization of existing methods allows for an improved integrated approach to confirm CHM diagnosis and carrier status in consideration of patient family history and available patient sample materials. CHM can be confirmed with an immunoblot assay. To detect the molecular cause of CHM, an examination of the genomic DNA or the mRNA must be performed. Presymptomatic carriers with no identifiable fundus signs can be identified only through molecular analysis of genomic DNA or through quantitative assays. PMID:24791138

Furgoch, Mira J.B.; Mewes-Ares, Jacqueline; Radziwon, Alina

2014-01-01

32

Molecular imaging of rheumatoid arthritis: emerging markers, tools, and techniques  

PubMed Central

Early diagnosis and effective monitoring of rheumatoid arthritis (RA) are important for a positive outcome. Instant treatment often results in faster reduction of inflammation and, as a consequence, less structural damage. Anatomical imaging techniques have been in use for a long time, facilitating diagnosis and monitoring of RA. However, mere imaging of anatomical structures provides little information on the processes preceding changes in synovial tissue, cartilage, and bone. Molecular imaging might facilitate more effective diagnosis and monitoring in addition to providing new information on the disease pathogenesis. A limiting factor in the development of new molecular imaging techniques is the availability of suitable probes. Here, we review which cells and molecules can be targeted in the RA joint and discuss the advances that have been made in imaging of arthritis with a focus on such molecular targets as folate receptor, F4/80, macrophage mannose receptor, E-selectin, intercellular adhesion molecule-1, phosphatidylserine, and matrix metalloproteinases. In addition, we discuss a new tool that is being introduced in the field, namely the use of nanobodies as tracers. Finally, we describe additional molecules displaying specific features in joint inflammation and propose these as potential new molecular imaging targets, more specifically receptor activator of nuclear factor ?B and its ligand, chemokine receptors, vascular cell adhesion molecule-1, ?V?3 integrin, P2X7 receptor, suppression of tumorigenicity 2, dendritic cell-specific transmembrane protein, and osteoclast-stimulatory transmembrane protein. PMID:25099015

2014-01-01

33

COAL AND CHAR STUDIES BY ADVANCED EMR TECHNIQUES  

SciTech Connect

Advanced electronic magnetic resonance (EMR) as well as nuclear magnetic resonance (NMR) methods have been used to examine properties of coals, chars, and molecular species related to constituents of coal. During the span of this grant, progress was made on construction and applications to coals and chars of two high frequency EMR systems particularly appropriate for such studies--48 GHz and 95 GHz electron magnetic resonance spectrometer, on new low-frequency dynamic nuclear polarization (DNP) experiments to examine the interaction between water and the surfaces of suspended char particulates in slurries, and on a variety of proton nuclear magnetic resonance (NMR) techniques to measure characteristics of the water directly in contact with the surfaces and pore spaces of carbonaceous particulates.

R. Linn Belford; Robert B. Clarkson; Mark J. Nilges; Boris M. Odintsov; Alex I. Smirnov

2001-04-30

34

Bringing Advanced Computational Techniques to Energy Research  

SciTech Connect

Please find attached our final technical report for the BACTER Institute award. BACTER was created as a graduate and postdoctoral training program for the advancement of computational biology applied to questions of relevance to bioenergy research.

Mitchell, Julie C

2012-11-17

35

Automatic Molecular Design using Evolutionary Techniques  

NASA Technical Reports Server (NTRS)

Molecular nanotechnology is the precise, three-dimensional control of materials and devices at the atomic scale. An important part of nanotechnology is the design of molecules for specific purposes. This paper describes early results using genetic software techniques to automatically design molecules under the control of a fitness function. The fitness function must be capable of determining which of two arbitrary molecules is better for a specific task. The software begins by generating a population of random molecules. The population is then evolved towards greater fitness by randomly combining parts of the better individuals to create new molecules. These new molecules then replace some of the worst molecules in the population. The unique aspect of our approach is that we apply genetic crossover to molecules represented by graphs, i.e., sets of atoms and the bonds that connect them. We present evidence suggesting that crossover alone, operating on graphs, can evolve any possible molecule given an appropriate fitness function and a population containing both rings and chains. Prior work evolved strings or trees that were subsequently processed to generate molecular graphs. In principle, genetic graph software should be able to evolve other graph representable systems such as circuits, transportation networks, metabolic pathways, computer networks, etc.

Globus, Al; Lawton, John; Wipke, Todd; Saini, Subhash (Technical Monitor)

1998-01-01

36

EDITORIAL: Advanced Measurement Techniques in Aerodynamics Advanced Measurement Techniques in Aerodynamics  

NASA Astrophysics Data System (ADS)

This issue of Measurement Science and Technology contains a special feature section with selected papers from the EWA International workshop on Advanced Measurement Techniques in Aerodynamics, which was held at the Delft University of Technology, Delft, The Netherlands, 31 March-1 April 2008. The workshop was funded by the European Windtunnel Association (EWA, www.eu-ewa.aero), which is an EU-funded network established in 2004 under the European Sixth Framework Programme with the goal of integrating and standardizing the different capabilities of European wind tunnels and related flow measurement techniques. The workshop was organized with the objective of stimulating discussion among leading European universities, research institutes and industry in the field of advanced aerodynamics measurement techniques, in order to provide a transfer of new ideas from upstream research centres to wind tunnel operators and industrial users. Non-intrusive flow diagnostic techniques nowadays offer renewed capabilities for industrial wind-tunnel applications. Particle image velocimetry (PIV) plays a leading role for particular applications (unsteady and complex flows, rotorcraft aerodynamics, turbulent separated flows) and can provide solutions that cannot be achieved with conventional techniques (e.g. in the analysis of vortex flows). This formed the main motivation to revise the state-of-the-art of PIV along with other non-intrusive optical techniques such as PSP, DGV and BOS. The two-day workshop contained sessions dedicated to several specific topics: rotorcraft aerodynamics applications; state-of-the-art of high-speed PIV and configurations for time-resolved measurements; three-dimensional PIV; non-intrusive load characterization by PSP and PIV. The main conclusion emerging from the closing discussion was that the new capabilities offered by time-resolved PIV are of great scientific and industrial interest for application to unsteady flows and in particular to the determination of unsteady aerodynamic forces and loads. We believe that this workshop provided a useful framework facilitating the transfer of new ideas from developer to the user communities. At the same time the workshop provided the upstream research community with important feedback about the areas of relevance for industrial aerodynamics.

van Oudheusden, B. W.; Scarano, F.

2009-07-01

37

Advances in Diagnostic Techniques for Induction Machines  

Microsoft Academic Search

This paper investigates diagnostic techniques for electrical machines with special reference to induction machines and to papers published in the last ten years. A comprehensive list of references is reported and examined, and research activities classified into four main topics: 1) electrical faults; 2) mechanical faults; 3) signal processing for analysis and monitoring; and 4) artificial intelligence and decision-making techniques.

Alberto Bellini; Fiorenzo Filippetti; Carla Tassoni; GÉrard-AndrÉ Capolino

2008-01-01

38

Application of molecular techniques on heterotrophic hydrogen production research  

Microsoft Academic Search

This paper reviews the application of molecular techniques in heterotrophic hydrogen production studies. Commonly used molecular techniques are introduced briefly first, including cloning-sequencing after polymerase chain reaction (PCR), denaturing gradient gel electrophoresis (DGGE), terminal-restriction fragment length polymorphism (T-RFLP), fluorescence in situ hybridization (FISH) and quantitative real-time PCR. Application of the molecular techniques in heterotrophic hydrogen production studies are discussed in

R. Y. Li; T. Zhang; H. H. P. Fang

2011-01-01

39

Advanced optical storage techniques for computers.  

PubMed

The growing demand for data storage in computing systems has stimulated the investigation of optical memory techniques because they offer a potential improvement in packing density of about two orders of magnitude over the apparent limits of conventional magnetic storage techniques. Physical properties and optical memory characteristics of magnetooptic thin-films of manganese bismuth have been investigated with regard to both bit-oriented and holographic memories. All the required technology for design of a bit-oriented memory appears to be available, but several key components required for a holographic memory still remain to be developed. PMID:20119301

Aagard, R L; Lee, T C; Chen, D

1972-10-01

40

Advances in Intelligent Methodologies and Techniques  

Microsoft Academic Search

This chapter introduces a number of intelligent methodologies and techniques stemmed from Artificial Intelligence (AI). An\\u000a overview of various intelligent models arisen from expert systems, artificial neural networks, fuzzy logic, genetic algorithms,\\u000a decision trees, and agent technologies is presented. Application examples of these intelligent models in various domains are\\u000a also presented. Then, the contribution of each chapter included in this

Lakhmi C. Jain; Chee Peng Lim

41

Advanced aerospace power distribution and control techniques.  

NASA Technical Reports Server (NTRS)

Conventional power distribution and control systems as employed in Apollo space vehicles and modern aircraft are reviewed, and arguments are presented in favor of applying some new techniques in the design of electric power systems for future manned spacecraft. Current Space Shuttle studies show that each pound of weight for supporting subsystems causes overall vehicle weight at launch to increase by 34.5 lb, with proportional cost penalty. The presently available technology for an improved automatic or semiautomatic distribution and control system should be implemented. A systems approach based on the most current technology is discussed along with a unique method of system development, testing, and evaluation.

Jeffcoat, T. D.; Eastman, F. E.

1972-01-01

42

Advances in laparoscopic techniques and instrumentation in standing equine surgery.  

PubMed

Equine standing surgery and laparoscopy are becoming increasingly important aspects of equine surgery. Laparoscopic advancements lag behind the human medical field, mainly due to decreased access to appropriate training and instrumentation. It is nearly impossible to cover the topic of equine standing surgery without discussing advances in laparoscopy, because without such advances, equine standing surgery lacks potential for forward progress. Although novel standing techniques continue to be published, the addition of minimally invasive laparoscopic techniques adds an entirely new dimension and provides a plethora of procedures to surgeons practicing equine standing surgery. PMID:24680205

Easley, Jeremiah T; Hendrickson, Dean A

2014-04-01

43

Advanced analysis techniques for uranium assay  

SciTech Connect

Uranium has a negligible passive neutron emission rate making its assay practicable only with an active interrogation method. The active interrogation uses external neutron sources to induce fission events in the uranium in order to determine the mass. This technique requires careful calibration with standards that are representative of the items to be assayed. The samples to be measured are not always well represented by the available standards which often leads to large biases. A technique of active multiplicity counting is being developed to reduce some of these assay difficulties. Active multiplicity counting uses the measured doubles and triples count rates to determine the neutron multiplication (f4) and the product of the source-sample coupling ( C ) and the 235U mass (m). Since the 35U mass always appears in the multiplicity equations as the product of Cm, the coupling needs to be determined before the mass can be known. A relationship has been developed that relates the coupling to the neutron multiplication. The relationship is based on both an analytical derivation and also on empirical observations. To determine a scaling constant present in this relationship, known standards must be used. Evaluation of experimental data revealed an improvement over the traditional calibration curve analysis method of fitting the doubles count rate to the 235Um ass. Active multiplicity assay appears to relax the requirement that the calibration standards and unknown items have the same chemical form and geometry.

Geist, W. H. (William H.); Ensslin, Norbert; Carrillo, L. A. (Louis A.); Beard, C. A. (Carl A.)

2001-01-01

44

Advanced characterization techniques for high power VCSELs  

NASA Astrophysics Data System (ADS)

The performance of high power VCSELs in a specific application depends on the geometrical and thermal design as well as on the quality of the epitaxially grown material. Due to the relatively high heat load in densely packed high power arrays the temperature in the active zone and the DBR mirrors changes significantly with the applied current and the traditional characterization methods become less meaningful than for low power devices. This paper presents a method to measure temperature independent power curves with the help of short pulse techniques and data mapping at different heat sink temperatures. In addition the internal quantum efficiency, the transparency current and the gain coefficient are measured by a novel method which operates the VCSEL material as an edge emitter and applies a cut-back technique. The optical losses in the DBR mirrors are determined using external feedback. In summary all relevant parameters which determine the quality of an epitaxial design are measured independently and can be directly compared with modeling and help to optimize the high power VCSEL performance.

Moench, Holger; Baier, Johannes; Gronenborn, Stephan; Kolb, Johanna; Miller, Michael; Pekarski, Pavel; Schemmann, Marcel; Valster, Adriaan

2010-02-01

45

Space charge profile measurement techniques: recent advances and future directions  

Microsoft Academic Search

Some of the advances in space charge measurement techniques over the last 5 years are described. It is concluded that significant further improvements in spatial resolution are unlikely in the next 5 years, except in the case of the LIMM technique implemented using very short laser pulses, where spatial resolution approaching 100 nm might be achievable. It is suggested that

R. J. Fleming

2005-01-01

46

Advances in relativistic molecular quantum mechanics  

NASA Astrophysics Data System (ADS)

A quantum mechanical equation H?=E? is composed of three components, viz., Hamiltonian H, wave function ?, and property E(?), each of which is confronted with fundamental issues in the relativistic regime, e.g., (1) What is the most appropriate relativistic many-body Hamiltonian? How to solve the resulting equation? (2) How does the relativistic wave function behave at the coalescence of two electrons? How to do relativistic explicit correlation? (3) How to formulate relativistic properties properly?, to name just a few. It is shown here that the charge-conjugated contraction of Fermion operators, dictated by the charge conjugation symmetry, allows for a bottom-up construction of a relativistic Hamiltonian that is in line with the principles of quantum electrodynamics (QED). Various approximate but accurate forms of the Hamiltonian can be obtained based entirely on physical arguments. In particular, the exact two-component Hamiltonians can be formulated in a general way to cast electric and magnetic fields, as well as electron self-energy and vacuum polarization, into a unified framework. While such algebraic two-component Hamiltonians are incompatible with explicit correlation, four-component relativistic explicitly correlated approaches can indeed be made fully parallel to the nonrelativistic counterparts by virtue of the ‘extended no-pair projection’ and the coalescence conditions. These findings open up new avenues for future developments of relativistic molecular quantum mechanics. In particular, ‘molecular QED’ will soon become an active and exciting field.

Liu, Wenjian

2014-04-01

47

Molecular Techniques to Assess Microbial Community Structure, Function, and Dynamics in the Environment  

Microsoft Academic Search

\\u000a Culture-based methods are important in investigating the microbial ecology of natural and anthropogenically impacted environments,\\u000a but they are extremely biased in their evaluation of microbial genetic diversity by selecting a particular population of microorganisms.\\u000a With recent advances in genomics and sequencing technologies, microbial community analyses using culture-independent molecular\\u000a techniques have initiated a new era of microbial ecology. Molecular analyses of

Gurdeep Rastogi; Rajesh K. Sani

48

The progress of DNA analyzing techniques and its impact on plant molecular systematics  

Microsoft Academic Search

Recent advances in manipulating nucleic acids have opened a new research field called plant molecular systematics. This short\\u000a review provides an overview of molecular techniques which have been used in the analysis of DNA molecules for the study of\\u000a plant systematics, with a special emphasis on PCR. The early application of DNA analysis, DNA\\/DNA hybridization, has not become\\u000a popular with

Toru Terachi

1993-01-01

49

Innovative Tools Advance Revolutionary Weld Technique  

NASA Technical Reports Server (NTRS)

The iconic, orange external tank of the space shuttle launch system not only contains the fuel used by the shuttle s main engines during liftoff but also comprises the shuttle s backbone, supporting the space shuttle orbiter and solid rocket boosters. Given the tank s structural importance and the extreme forces (7.8 million pounds of thrust load) and temperatures it encounters during launch, the welds used to construct the tank must be highly reliable. Variable polarity plasma arc welding, developed for manufacturing the external tank and later employed for building the International Space Station, was until 1994 the best process for joining the aluminum alloys used during construction. That year, Marshall Space Flight Center engineers began experimenting with a relatively new welding technique called friction stir welding (FSW), developed in 1991 by The Welding Institute, of Cambridge, England. FSW differs from traditional fusion welding in that it is a solid-state welding technique, using frictional heat and motion to join structural components without actually melting any of the material. The weld is created by a shouldered pin tool that is plunged into the seam of the materials to be joined. The tool traverses the line while rotating at high speeds, generating friction that heats and softens but does not melt the metal. (The heat produced approaches about 80 percent of the metal s melting temperature.) The pin tool s rotation crushes and stirs the plasticized metal, extruding it along the seam as the tool moves forward. The material cools and consolidates, resulting in a weld with superior mechanical properties as compared to those weld properties of fusion welds. The innovative FSW technology promises a number of attractive benefits. Because the welded materials are not melted, many of the undesirables associated with fusion welding porosity, cracking, shrinkage, and distortion of the weld are minimized or avoided. The process is more energy efficient, safe (no toxic smoke or shielding gas, liquid metal splatter, arcing, dangerous voltage, or radiation), and environmentally sound (no consumables, fumes, or noise) than fusion welding. Under computer control, an automated FSW machine can create welds with high reproducibility, improving efficiency and overall quality of manufactured materials. The process also allows for welding dissimilar metals as well as those metals considered to be "unweldable" such as the 7xxx series aluminum alloys. Its effectiveness and versatility makes FSW useful for aerospace, rail, automotive, marine, and military applications. A downside to FSW, however, is the keyhole opening left in the weld when the FSW pin tool exits the weld joint. This is a significant problem when using the FSW process to join circumferential structures such as pipes and storage containers. Furthermore, weld joints that taper in material thickness also present problems when using the conventional FSW pin tool, because the threaded pin rotating within the weld joint material is a fixed length. There must be capability for the rotating pin to both increase and decrease in length in real time while welding the tapered material. (Both circumferential and tapered thickness weldments are found in the space shuttle external tank.) Marshall engineers addressed both the keyhole and tapered material thickness problems by developing the auto-adjustable pin tool. This unique piece of equipment automatically withdraws the pin into the tool s shoulder for keyhole closeout. In addition, the auto-adjustable pin tool retracts, or shortens, the rotating pin while welding a weld joint that tapers from one thickness to a thinner thickness. This year, the impact of the Marshall innovation was recognized with an "Excellence in Technology Transfer Award" from the Federal Laboratory Consortium.

2009-01-01

50

Advances in molecular imaging: targeted optical contrast agents for cancer diagnostics  

PubMed Central

Over the last three decades, our understanding of the molecular changes associated with cancer development and progression has advanced greatly. This has led to new cancer therapeutics targeted against specific molecular pathways; such therapies show great promise to reduce mortality, in part by enabling physicians to tailor therapy for patients based on a molecular profile of their tumor. Unfortunately, the tools for definitive cancer diagnosis – light microscopic examination of biopsied tissue stained with nonspecific dyes – remain focused on the analysis of tissue ex vivo. There is an important need for new clinical tools to support the molecular diagnosis of cancer. Optical molecular imaging is emerging as a technique to help meet this need. Targeted, optically active contrast agents can specifically label extra-and intracellular biomarkers of cancer. Optical images can be acquired in real time with high spatial resolution to image-specific molecular targets, while still providing morphologic context. This article reviews recent advances in optical molecular imaging, highlighting the advances in technology required to improve early cancer detection, guide selection of targeted therapy and rapidly evaluate therapeutic efficacy. PMID:22385200

Hellebust, Anne; Richards-Kortum, Rebecca

2012-01-01

51

Advanced Fault Diagnosis Methods in Molecular Networks  

PubMed Central

Analysis of the failure of cell signaling networks is an important topic in systems biology and has applications in target discovery and drug development. In this paper, some advanced methods for fault diagnosis in signaling networks are developed and then applied to a caspase network and an SHP2 network. The goal is to understand how, and to what extent, the dysfunction of molecules in a network contributes to the failure of the entire network. Network dysfunction (failure) is defined as failure to produce the expected outputs in response to the input signals. Vulnerability level of a molecule is defined as the probability of the network failure, when the molecule is dysfunctional. In this study, a method to calculate the vulnerability level of single molecules for different combinations of input signals is developed. Furthermore, a more complex yet biologically meaningful method for calculating the multi-fault vulnerability levels is suggested, in which two or more molecules are simultaneously dysfunctional. Finally, a method is developed for fault diagnosis of networks based on a ternary logic model, which considers three activity levels for a molecule instead of the previously published binary logic model, and provides equations for the vulnerabilities of molecules in a ternary framework. Multi-fault analysis shows that the pairs of molecules with high vulnerability typically include a highly vulnerable molecule identified by the single fault analysis. The ternary fault analysis for the caspase network shows that predictions obtained using the more complex ternary model are about the same as the predictions of the simpler binary approach. This study suggests that by increasing the number of activity levels the complexity of the model grows; however, the predictive power of the ternary model does not appear to be increased proportionally. PMID:25290670

Habibi, Iman; Emamian, Effat S.; Abdi, Ali

2014-01-01

52

GENE 8600 GENETICS SEMINAR Description: Seminars emphasizing advances in genetics, molecular genetics,  

E-print Network

GENE 8600 GENETICS SEMINAR Description: Seminars emphasizing advances in genetics, molecular genetics, and molecular biology. Course Objectives Students will gain experience in reading and presenting the primary literature in genetics, molecular genetics, and molecular biology. Evaluations will be based

Arnold, Jonathan

53

Advanced wiring technique and hardware application: Airplane and space vehicle  

NASA Technical Reports Server (NTRS)

An advanced wiring system is described which achieves the safety/reliability required for present and future airplane and space vehicle applications. Also, present wiring installation techniques and hardware are analyzed to establish existing problem areas. An advanced wiring system employing matrix interconnecting unit, plug to plug trunk bundles (FCC or ribbon cable) is outlined, and an installation study presented. A planned program to develop, lab test and flight test key features of these techniques and hardware as a part of the SST technology follow-on activities is discussed.

Ernst, H. L.; Eichman, C. D.

1972-01-01

54

Application of molecular techniques on heterotrophic hydrogen production research.  

PubMed

This paper reviews the application of molecular techniques in heterotrophic hydrogen production studies. Commonly used molecular techniques are introduced briefly first, including cloning-sequencing after polymerase chain reaction (PCR), denaturing gradient gel electrophoresis (DGGE), terminal-restriction fragment length polymorphism (T-RFLP), fluorescence in situ hybridization (FISH) and quantitative real-time PCR. Application of the molecular techniques in heterotrophic hydrogen production studies are discussed in details, focusing on identification of new isolates for hydrogen production, characterization of microbial compositions in bioreactors, monitoring microbial diversity variation, visualization of microbial distribution in hydrogen-producing granular sludge, and quantification of various microbial populations. Some significant findings in recent hydrogen production studies with the application of molecular techniques are discussed, followed by a research outlook of the heterotrophic biohydrogen field. PMID:21398117

Li, R Y; Zhang, T; Fang, H H P

2011-09-01

55

Applications of molecular biology techniques to transfusion medicine  

Microsoft Academic Search

Other articles in this issue of Seminars in Hematology have reviewed the results of basic research in relation to the understanding of the genes, the molecular basis of blood group variants, and structural and functional aspects of the proteins carrying blood group antigens. Although molecular techniques are currently being used in a limited fashion in clinical laboratories, their application has

Marion E Reid; Maria Rios; Karina Yazdanbakhsh

2000-01-01

56

Teaching Molecular Biological Techniques in a Research Content  

ERIC Educational Resources Information Center

Molecular biological methods, such as the polymerase chain reaction (PCR) and gel electrophoresis, are now commonly taught to students in introductory biology courses at the college and even high school levels. This often includes hands-on experience with one or more molecular techniques as part of a general biology laboratory. To assure that most…

Stiller, John W.; Coggins, T. Chad

2006-01-01

57

MIMO Systems: Principles, iterative techniques and advanced polarization  

E-print Network

. . . . . . . . . . . . . . . . . . . . . . . 7 1.3.2 MIMO Capacity . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 8 1.3.3 Some next study the "MIMO channel capacity" and present the early developments in these systems, concerningMIMO Systems: Principles, iterative techniques and advanced polarization K. Raoof 1 , M.A. Khalighi

Paris-Sud XI, Université de

58

ADVANCES AND NEW TECHNIQUES IN LENGTH MEASUREMENTS BY OPTICAL INTERFEROMETRY  

Microsoft Academic Search

Studies of a long gauge block Kösters interferometer, performed at INMETRO, and the results of the CIPM Key Comparison CCL-2 show that the uncertainty in realization of the SI length unit achieved with this type of instrument in the range of 500 mm is ~1 part in 108. Basic advances in philosophy and techniques of high-precision temperature measurements, realized in

Alexandre Titov; Igor Malinovsky

59

Advanced Marketing Core Curriculum. Test Items and Assessment Techniques.  

ERIC Educational Resources Information Center

This document contains duties and tasks, multiple-choice test items, and other assessment techniques for Missouri's advanced marketing core curriculum. The core curriculum begins with a list of 13 suggested textbook resources. Next, nine duties with their associated tasks are given. Under each task appears one or more citations to appropriate…

Smith, Clifton L.; And Others

60

Stochastic molecular dynamics: A combined Monte Carlo and molecular dynamics technique for isothermal simulations  

E-print Network

Stochastic molecular dynamics: A combined Monte Carlo and molecular dynamics technique for isothermal simulations Phil Attard Ian Wark Research Institute, University of South Australia, Mawson Lakes dynamics technique is developed that gives equations of motion for an isothermal system. Test results

Attard, Phil

61

Airborne myxomycete spores: detection using molecular techniques.  

PubMed

Myxomycetes are organisms characterized by a life cycle that includes a fruiting body stage. Myxomycete fruiting bodies contain spores, and wind dispersal of the spores is considered important for this organism to colonize new areas. In this study, the presence of airborne myxomycetes and the temporal changes in the myxomycete composition of atmospheric particles (aerosols) were investigated with a polymerase chain reaction (PCR)-based method for Didymiaceae and Physaraceae. Twenty-one aerosol samples were collected on the roof of a three-story building located in Sapporo, Hokkaido Island, northern Japan. PCR analysis of DNA extracts from the aerosol samples indicated the presence of airborne myxomycetes in all the samples, except for the one collected during the snowfall season. Denaturing gradient gel electrophoresis (DGGE) analysis of the PCR products showed seasonally varying banding patterns. The detected DGGE bands were subjected to sequence analyses, and four out of nine obtained sequences were identical to those of fruiting body samples collected in Hokkaido Island. It appears that the difference in the fruiting period of each species was correlated with the seasonal changes in the myxomycete composition of the aerosols. Molecular evidence shows that newly formed spores are released and dispersed in the air, suggesting that wind-driven dispersal of spores is an important process in the life history of myxomycetes. This study is the first to detect airborne myxomycetes with the use of molecular ecological analyses and to characterize their seasonal distribution. PMID:18836695

Kamono, Akiko; Kojima, Hisaya; Matsumoto, Jun; Kawamura, Kimitaka; Fukui, Manabu

2009-01-01

62

Airborne myxomycete spores: detection using molecular techniques  

NASA Astrophysics Data System (ADS)

Myxomycetes are organisms characterized by a life cycle that includes a fruiting body stage. Myxomycete fruiting bodies contain spores, and wind dispersal of the spores is considered important for this organism to colonize new areas. In this study, the presence of airborne myxomycetes and the temporal changes in the myxomycete composition of atmospheric particles (aerosols) were investigated with a polymerase chain reaction (PCR)-based method for Didymiaceae and Physaraceae. Twenty-one aerosol samples were collected on the roof of a three-story building located in Sapporo, Hokkaido Island, northern Japan. PCR analysis of DNA extracts from the aerosol samples indicated the presence of airborne myxomycetes in all the samples, except for the one collected during the snowfall season. Denaturing gradient gel electrophoresis (DGGE) analysis of the PCR products showed seasonally varying banding patterns. The detected DGGE bands were subjected to sequence analyses, and four out of nine obtained sequences were identical to those of fruiting body samples collected in Hokkaido Island. It appears that the difference in the fruiting period of each species was correlated with the seasonal changes in the myxomycete composition of the aerosols. Molecular evidence shows that newly formed spores are released and dispersed in the air, suggesting that wind-driven dispersal of spores is an important process in the life history of myxomycetes. This study is the first to detect airborne myxomycetes with the use of molecular ecological analyses and to characterize their seasonal distribution.

Kamono, Akiko; Kojima, Hisaya; Matsumoto, Jun; Kawamura, Kimitaka; Fukui, Manabu

2009-01-01

63

Recent Advances in Molecular, Multimodal and Theranostic Ultrasound Imaging  

PubMed Central

Ultrasound (US) imaging is an exquisite tool for the non-invasive and real-time diagnosis of many different diseases. In this context, US contrast agents can improve lesion delineation, characterization and therapy response evaluation. US contrast agents are usually micrometer-sized gas bubbles, stabilized with soft or hard shells. By conjugating antibodies to the microbubble (MB) surface, and by incorporating diagnostic agents, drugs or nucleic acids into or onto the MB shell, molecular, multimodal and theranostic MB can be generated. We here summarize recent advances in molecular, multimodal and theranostic US imaging, and introduce concepts how such advanced MB can be generated, applied and imaged. Examples are given for their use to image and treat oncological, cardiovascular and neurological diseases. Furthermore, we discuss for which therapeutic entities incorporation into (or conjugation to) MB is meaningful, and how US-mediated MB destruction can increase their extravasation, penetration, internalization and efficacy. PMID:24316070

Kiessling, Fabian; Fokong, Stanley; Bzyl, Jessica; Lederle, Wiltrud; Palmowski, Moritz; Lammers, Twan

2014-01-01

64

Recent Advances in the Molecular Characterization of Circulating Tumor Cells  

PubMed Central

Although circulating tumor cells (CTCs) were first observed over a century ago, lack of sensitive methodology precluded detailed study of these cells until recently. However, technological advances have now facilitated the identification, enumeration, and characterization of CTCs using a variety of methods. The majority of evidence supporting the use of CTCs in clinical decision-making has been related to enumeration using the CellSearch® system and correlation with prognosis. Growing evidence also suggests that CTC monitoring can provide an early indication of patient treatment response based on comparison of CTC levels before and after therapy. However, perhaps the greatest potential that CTCs hold for oncology lies at the level of molecular characterization. Clinical treatment decisions may be more effective if they are based on molecular characteristics of metastatic cells rather than on those of the primary tumor alone. Molecular characterization of CTCs (which can be repeatedly isolated in a minimally invasive fashion) provides the opportunity for a “real-time liquid biopsy” that allows assessment of genetic drift, investigation of molecular disease evolution, and identification of actionable genomic characteristics. This review focuses on recent advances in this area, including approaches involving immunophenotyping, fluorescence in situ hybridization (FISH), multiplex RT-PCR, microarray, and genomic sequencing. PMID:24633084

Lowes, Lori E.; Allan, Alison L.

2014-01-01

65

Recent Advances in Molecular Diagnosis of Thyroid Cancer  

PubMed Central

Recent molecular studies have described a number of abnormalities associated with the progression and dedifferentiation of thyroid carcinoma. These distinct molecular events are often associated with specific stages of tumor development. In particular, remarkable advances have occurred in several major biological areas of thyroid cancer, including the molecular alterations for the loss of radioiodine avidity of thyroid cancer, the pathogenic role of the MAP kinase and PI3K/Akt pathways and their related genetic alterations, and the aberrant methylation of functionally important genes in thyroid tumorigenesis and pathogenesis. Recognition of these features is crucial to the management of patients with thyroid cancer. Novel treatments are being designed based on our enhanced understanding of this disease process. PMID:21603167

Legakis, Ioannis; Syrigos, Konstantinos

2011-01-01

66

Recent advances in sample preparation techniques for effective bioanalytical methods.  

PubMed

This paper reviews the recent developments in bioanalysis sample preparation techniques and gives an update on basic principles, theory, applications and possibilities for automation, and a comparative discussion on the advantages and limitation of each technique. Conventional liquid-liquid extraction (LLE), protein precipitation (PP) and solid-phase extraction (SPE) techniques are now been considered as methods of the past. The last decade has witnessed a rapid development of novel sample preparation techniques in bioanalysis. Developments in SPE techniques such as selective sorbents and in the overall approach to SPE, such as hybrid SPE and molecularly imprinted polymer SPE, have been addressed. Considerable literature has been published in the area of solid-phase micro-extraction and its different versions, e.g. stir bar sorptive extraction, and their application in the development of selective and sensitive bioanalytical methods. Techniques such as dispersive solid-phase extraction, disposable pipette extraction and micro-extraction by packed sorbent offer a variety of extraction phases and provide unique advantages to bioanalytical methods. On-line SPE utilizing column-switching techniques is rapidly gaining acceptance in bioanalytical applications. PP sample preparation techniques such as PP filter plates/tubes offer many advantages like removal of phospholipids and proteins in plasma/serum. Newer approaches to conventional LLE techniques (salting-out LLE) are also covered in this review article. PMID:21154887

Kole, Prashant Laxman; Venkatesh, Gantala; Kotecha, Jignesh; Sheshala, Ravi

2011-01-01

67

Advances in finite difference techniques for computational fluid dynamics  

NASA Astrophysics Data System (ADS)

Discretization methods, geometry treatments, and solution processes of CFD techniques are presented. In the first area, discretization methods, the major advance is the development of a unified picture of the role of interpolation in the construction of numerical methods. In the second area, geometry treatment, grid approaches are proving to be very versatile in facilitating the treatment of complex topologies. In the third area of solution methods, the major advance is the unification of time-marching and space-marching techniques. A treatment of total variation diminishing and uniformly nonoscillatory formulations is given, together with a detailed presentation of a finite volume procedure for the three-dimensional Euler equations. The formulation of the unified time and space marching method and examples using the above in a multizone gridding framework are also noted.

Chakravarthy, Sukumar R.; Szema, Kuo-Yen

68

Technology development of fabrication techniques for advanced solar dynamic concentrators  

NASA Technical Reports Server (NTRS)

The objective of the advanced concentrator program is to develop the technology that will lead to lightweight, highly reflective, accurate, scaleable, and long lived space solar dynamic concentrators. The advanced concentrator program encompasses new and innovative concepts, fabrication techniques, materials selection, and simulated space environmental testing. Fabrication techniques include methods of fabricating the substrates and coating substrate surfaces to produce high quality optical surfaces, acceptable for further coating with vapor deposited optical films. The selected materials to obtain a high quality optical surface include microsheet glass and Eccocoat EP-3 epoxy, with DC-93-500 selected as a candidate silicone adhesive and levelizing layer. The following procedures are defined: cutting, cleaning, forming, and bonding microsheet glass. Procedures are also defined for surface cleaning, and EP-3 epoxy application. The results and analyses from atomic oxygen and thermal cycling tests are used to determine the effects of orbital conditions in a space environment.

Richter, Scott W.

1991-01-01

69

Advance techniques for monitoring human tolerance to positive Gz accelerations  

NASA Technical Reports Server (NTRS)

Tolerance to positive g accelerations was measured in ten normal male subjects using both standard and advanced techniques. In addition to routine electrocardiogram, heart rate, respiratory rate, and infrared television, monitoring techniques during acceleration exposure included measurement of peripheral vision loss, noninvasive temporal, brachial, and/or radial arterial blood flow, and automatic measurement of indirect systolic and diastolic blood pressure at 60-sec intervals. Although brachial and radial arterial flow measurements reflected significant cardiovascular changes during and after acceleration, they were inconsistent indices of the onset of grayout or blackout. Temporal arterial blood flow, however, showed a high correlation with subjective peripheral light loss.

Pelligra, R.; Sandler, H.; Rositano, S.; Skrettingland, K.; Mancini, R.

1973-01-01

70

Stem cell systems informatics for advanced clinical biodiagnostics: tracing molecular signatures from bench to bedside  

PubMed Central

Development of innovative high throughput technologies has enabled a variety of molecular landscapes to be interrogated with an unprecedented degree of detail. Emergence of next generation nucleotide sequencing methods, advanced proteomic techniques, and metabolic profiling approaches continue to produce a wealth of biological data that captures molecular frameworks underlying phenotype. The advent of these novel technologies has significant translational applications, as investigators can now explore molecular underpinnings of developmental states with a high degree of resolution. Application of these leading-edge techniques to patient samples has been successfully used to unmask nuanced molecular details of disease vs healthy tissue, which may provide novel targets for palliative intervention. To enhance such approaches, concomitant development of algorithms to reprogram differentiated cells in order to recapitulate pluripotent capacity offers a distinct advantage to advancing diagnostic methodology. Bioinformatic deconvolution of several “-omic” layers extracted from reprogrammed patient cells, could, in principle, provide a means by which the evolution of individual pathology can be developmentally monitored. Significant logistic challenges face current implementation of this novel paradigm of patient treatment and care, however, several of these limitations have been successfully addressed through continuous development of cutting edge in silico archiving and processing methods. Comprehensive elucidation of genomic, transcriptomic, proteomic, and metabolomic networks that define normal and pathological states, in combination with reprogrammed patient cells are thus poised to become high value resources in modern diagnosis and prognosis of patient disease. PMID:23986272

Faustino, Randolph S.; Arrell, D. Kent; Folmes, Clifford D.L.; Terzic, Andre; Perez-Terzic, Carmen

2013-01-01

71

A Brief Review of Molecular Techniques to Assess Plant Diversity  

PubMed Central

Massive loss of valuable plant species in the past centuries and its adverse impact on environmental and socioeconomic values has triggered the conservation of plant resources. Appropriate identification and characterization of plant materials is essential for the successful conservation of plant resources and to ensure their sustainable use. Molecular tools developed in the past few years provide easy, less laborious means for assigning known and unknown plant taxa. These techniques answer many new evolutionary and taxonomic questions, which were not previously possible with only phenotypic methods. Molecular techniques such as DNA barcoding, random amplified polymorphic DNA (RAPD), amplified fragment length polymorphism (AFLP), microsatellites and single nucleotide polymorphisms (SNP) have recently been used for plant diversity studies. Each technique has its own advantages and limitations. These techniques differ in their resolving power to detect genetic differences, type of data they generate and their applicability to particular taxonomic levels. This review presents a basic description of different molecular techniques that can be utilized for DNA fingerprinting and molecular diversity analysis of plant species. PMID:20559503

Arif, Ibrahim A.; Bakir, Mohammad A.; Khan, Haseeb A.; Al Farhan, Ahmad H.; Al Homaidan, Ali A.; Bahkali, Ali H.; Sadoon, Mohammad Al; Shobrak, Mohammad

2010-01-01

72

Inside Out: A Novel Labral Repair and Advancement Technique  

PubMed Central

Labral tears are a significant cause of hip pain and are currently the most common indication for hip arthroscopy. Compared with labral debridement, labral repair has significantly better outcomes in terms of both daily activities and athletic pursuits in the setting of femoral acetabular impingement. The techniques described in the literature all use anchor placement on the capsular aspect of the acetabular rim, which can be difficult especially anteriorly, where the rim is very thin, and has the potential for significant complications. Anchor breakage, anchor slippage into the surrounding (capsular side) soft tissue, and penetration of the cartilage surface are among the most common complications. We describe an intra-articular anchor placement technique for labral repair from inside out. This technique, because of the location of the anchor and direction of suture pull, can assist in labral advancement in cases in which the native labrum fails to create a seal because of its location away from the femoral head. PMID:24904768

Mei-Dan, Omer; Pascual-Garrido, Cecilia; Kark, Jonathan A.; McConkey, Mark O.

2014-01-01

73

Recent Molecular Advances on Downstream Plant Responses to Abiotic Stress  

PubMed Central

Abiotic stresses such as extremes of temperature and pH, high salinity and drought, comprise some of the major factors causing extensive losses to crop production worldwide. Understanding how plants respond and adapt at cellular and molecular levels to continuous environmental changes is a pre-requisite for the generation of resistant or tolerant plants to abiotic stresses. In this review we aimed to present the recent advances on mechanisms of downstream plant responses to abiotic stresses and the use of stress-related genes in the development of genetically engineered crops. PMID:22942725

dos Reis, Savio Pinho; Lima, Aline Medeiros; de Souza, Claudia Regina Batista

2012-01-01

74

An Effective Technique for Endoscopic Resection of Advanced Stage Angiofibroma  

PubMed Central

Introduction: In recent years, the surgical management of angiofibroma has been greatly influenced by the use of endoscopic techniques. However, large tumors that extend into difficult anatomic sites present major challenges for management by either endoscopy or an open-surgery approach which needs new technique for the complete en block resection. Materials and Methods: In a prospective observational study we developed an endoscopic transnasal technique for the resection of angiofibroma via pushing and pulling the mass with 1/100000 soaked adrenalin tampons. Thirty two patients were treated using this endoscopic technique over 7 years. The mean follow-up period was 36 months. The main outcomes measured were tumor staging, average blood loss, complications, length of hospitalization, and residual and/or recurrence rate of the tumor. Results: According to the Radkowski staging, 23,5, and 4 patients were at stage IIC, IIIA, and IIIB, respectively. Twenty five patients were operated on exclusively via transnasal endoscopy while 7 patients were managed using endoscopy-assisted open-surgery techniques. Mean blood loss in patients was 1261± 893 cc. The recurrence rate was 21.88% (7 cases) at two years following surgery. Mean hospitalization time was 3.56 ± 0.6 days. Conclusion: Using this effective technique, endoscopic removal of more highly advanced angiofibroma is possible. Better visualization, less intraoperative blood loss, lower rates of complication and recurrence, and shorter hospitalization time are some of the advantages. PMID:24505571

Mohammadi Ardehali, Mojtaba; Samimi, Seyyed Hadi; Bakhshaee, Mehdi

2014-01-01

75

Protein-Folding Dynamics: Overview of Molecular Simulation Techniques  

Microsoft Academic Search

Molecular dynamics (MD) is an invaluable tool with which to study protein folding in silico. Although just a few years ago the dynamic behavior of a protein molecule could be simulated only in the neighborhood of the experimental conformation (or protein unfolding could be simulated at high temperature), the advent of distributed computing, new techniques such as replica-exchange MD, new

Harold A. Scheraga; Mey Khalili; Adam Liwo

2007-01-01

76

Advanced aeroservoelastic stabilization techniques for hypersonic flight vehicles  

NASA Technical Reports Server (NTRS)

Advanced high performance vehicles, including Single-Stage-To-Orbit (SSTO) hypersonic flight vehicles, that are statically unstable, require higher bandwidth flight control systems to compensate for the instability resulting in interactions between the flight control system, the engine/propulsion dynamics, and the low frequency structural modes. Military specifications, such as MIL-F-9490D and MIL-F-87242, tend to limit treatment of structural modes to conventional gain stabilization techniques. The conventional gain stabilization techniques, however, introduce low frequency effective time delays which can be troublesome from a flying qualities standpoint. These time delays can be alleviated by appropriate blending of gain and phase stabilization techniques (referred to as Hybrid Phase Stabilization or HPS) for the low frequency structural modes. The potential of using HPS for compensating structural mode interaction was previously explored. It was shown that effective time delay was significantly reduced with the use of HPS; however, the HPS design was seen to have greater residual response than a conventional gain stablized design. Additional work performed to advance and refine the HPS design procedure, to further develop residual response metrics as a basis for alternative structural stability specifications, and to develop strategies for validating HPS design and specification concepts in manned simulation is presented. Stabilization design sensitivity to structural uncertainties and aircraft-centered requirements are also assessed.

Chan, Samuel Y.; Cheng, Peter Y.; Myers, Thomas T.; Klyde, David H.; Magdaleno, Raymond E.; Mcruer, Duane T.

1992-01-01

77

Molecular Vapor Deposition - An Improved Vapor-Phase Deposition Technique of Molecular Coatings for MEMS Devices  

Microsoft Academic Search

This paper reports the results of a new surface modification technique called Molecular Vapor Deposition (MVD). The MVD technique is an enhancement of a conventional vapor deposition of ultra-thin organic molecules by incorporating an in-situ surface plasma treatment and the precise delivery of precursor vapors. Properties of the MVD coatings can be tailored and were found to exhibit superior performance

Boris Kobrin; Victor Fuentes; Srikanth Dasaradhi; Richard Yi; Romuald Nowak; Jeff Chinn; Robert Ashurst; Carlo Carraro; Roya Maboudian

2004-01-01

78

CD52 is a molecular target in advanced systemic mastocytosis.  

PubMed

Advanced systemic mastocytosis (SM) is an aggressive hematopoietic neoplasm with poor prognosis and short survival times. So far, no curative therapy is available for affected patients. We have identified the cell surface antigen CD52 (CAMPATH-1) as a molecular target expressed abundantly on the surface of primary neoplastic mast cells (MCs) in patients with advanced SM. In contrast, neoplastic MCs of patients with indolent SM and normal MCs expressed only low levels or did not express CD52. To study the mechanisms of CD52 expression and the value of this antigen as a potential therapeutic target, we generated a human MC cell line, designated MCPV-1, by lentiviral immortalization of cord blood-derived MC progenitor cells. Functional studies revealed that activated RAS profoundly promotes surface expression of CD52. The CD52-targeting antibody alemtuzumab induced cell death in CD52(+) primary neoplastic MCs obtained from patients with SM as well as in MCPV-1 cells. NSG mice xenotransplanted with MCPV-1 cells survived significantly longer after treatment with alemtuzumab (median survival: 31 d untreated vs. 46 d treated; P=0.0012). We conclude that CD52 is a novel marker and potential therapeutic target in neoplastic MCs in patients with advanced SM. PMID:24760752

Hoermann, Gregor; Blatt, Katharina; Greiner, Georg; Putz, Eva Maria; Berger, Angelika; Herrmann, Harald; Cerny-Reiterer, Sabine; Gleixner, Karoline V; Walz, Christoph; Hoetzenecker, Konrad; Müllauer, Leonhard; Reiter, Andreas; Sotlar, Karl; Sexl, Veronika; Valent, Peter; Mayerhofer, Matthias

2014-08-01

79

Measuring the microbiome: perspectives on advances in DNA-based techniques for exploring microbial life  

PubMed Central

This article reviews recent advances in ‘microbiome studies’: molecular, statistical and graphical techniques to explore and quantify how microbial organisms affect our environments and ourselves given recent increases in sequencing technology. Microbiome studies are moving beyond mere inventories of specific ecosystems to quantifications of community diversity and descriptions of their ecological function. We review the last 24 months of progress in this sort of research, and anticipate where the next 2 years will take us. We hope that bioinformaticians will find this a helpful springboard for new collaborations with microbiologists. PMID:22308073

Bunge, John; Gilbert, Jack A.; Moore, Jason H.

2012-01-01

80

Recent advances in molecular diagnostics of hepatitis B virus  

PubMed Central

Hepatitis B virus (HBV) is one of the important global health problems today. Infection with HBV can lead to a variety of clinical manifestations including severe hepatic complications like liver cirrhosis and hepatocellular carcinoma. Presently, routine HBV screening and diagnosis is primarily based on the immuno-detection of HBV surface antigen (HBsAg). However, identification of HBV DNA positive cases, who do not have detectable HBsAg has greatly encouraged the use of nucleic acid amplification based assays, that are highly sensitive, specific and are to some extent tolerant to sequence variation. In the last few years, the field of HBV molecular diagnostics has evolved rapidly with advancements in the molecular biology tools, such as polymerase chain reaction (PCR) and real-time PCR. Recently, apart of PCR based amplification methods, a number of isothermal amplification assays, such as loop mediated isothermal amplification, transcription mediated amplification, ligase chain reaction, and rolling circle amplification have been utilized for HBV diagnosis. These assays also offer options for real time detection and integration into biosensing devices. In this manuscript, we review the molecular technologies that are presently available for HBV diagnostics, with special emphasis on isothermal amplification based technologies. We have also included the recent trends in the development of biosensors and use of next generation sequencing technologies for HBV.

Datta, Sibnarayan; Chatterjee, Soumya; Veer, Vijay

2014-01-01

81

Advanced bronchoscopic techniques in diagnosis and staging of lung cancer  

PubMed Central

The role of advanced brochoscopic diagnostic techniques in detection and staging of lung cancer has steeply increased in recent years. Bronchoscopic imaging techniques became widely available and easy to use. Technical improvement led to merging in technologies making autofluorescence or narrow band imaging incorporated into one bronchoscope. New tools, such as autofluorescence imagining (AFI), narrow band imaging (NBI) or fuji intelligent chromo endoscopy (FICE), found their place in respiratory endoscopy suites. Development of endobronchial ultrasound (EBUS) improved minimally invasive mediastinal staging and diagnosis of peripheral lung lesions. Linear EBUS proven to be complementary to mediastinoscopy. This technique is now available in almost all high volume centers performing bronchoscopy. Radial EBUS with mini-probes and guiding sheaths provides accurate diagnosis of peripheral pulmonary lesions. Combining EBUS guided procedures with rapid on site cytology (ROSE) increases diagnostic yield even more. Electromagnetic navigation technology (EMN) is also widely used for diagnosis of peripheral lesions. Future development will certainly lead to new improvements in technology and creation of new sophisticated tools for research in respiratory endoscopy. Broncho-microscopy, alveoloscopy, optical coherence tomography are some of the new research techniques emerging for rapid technological development. PMID:24102008

Zaric, Bojan; Stojsic, Vladimir; Sarcev, Tatjana; Stojanovic, Goran; Carapic, Vladimir; Perin, Branislav; Darwiche, Kaid; Tsakiridis, Kosmas; Karapantzos, Ilias; Kesisis, Georgios; Kougioumtzi, Ioanna; Katsikogiannis, Nikolaos; Machairiotis, Nikolaos; Stylianaki, Aikaterini; Foroulis, Christophoros N.; Zarogoulidis, Konstantinos

2013-01-01

82

Advanced in situ spectroscopic techniques and their applications in environmental biogeochemistry: introduction to the special section.  

PubMed

Understanding the molecular-scale complexities and interplay of chemical and biological processes of contaminants at solid, liquid, and gas interfaces is a fundamental and crucial element to enhance our understanding of anthropogenic environmental impacts. The ability to describe the complexity of environmental biogeochemical reaction mechanisms relies on our analytical ability through the application and developmemnt of advanced spectroscopic techniques. Accompanying this introductory article are nine papers that either review advanced in situ spectroscopic methods or present original research utilizing these techniques. This collection of articles summarizes the challenges facing environmental biogeochemistry, highlights the recent advances and scientific gaps, and provides an outlook into future research that may benefit from the use of in situ spectroscopic approaches. The use of synchrotron-based techniques and other methods are discussed in detail, as is the importance to integrate multiple analytical approaches to confirm results of complementary procedures or to fill data gaps. We also argue that future direction in research will be driven, in addition to recent analytical developments, by emerging factors such as the need for risk assessment of new materials (i.e., nanotechnologies) and the realization that biogeochemical processes need to be investigated in situ under environmentally relevant conditions. PMID:21546653

Lombi, Enzo; Hettiarachchi, Ganga M; Scheckel, Kirk G

2011-01-01

83

2010NatureAmerica,Inc.Allrightsreserved. nature structural & molecular biology advance online publication  

E-print Network

©2010NatureAmerica,Inc.Allrightsreserved. nature structural & molecular biology advance online and Manton Center for Orphan Disease, Children's Hospital Boston, Boston, Massachusetts, USA. 2Department

Clapham, David E.

84

Advanced Techniques for Removal of Retrievable Inferior Vena Cava Filters  

SciTech Connect

Inferior vena cava (IVC) filters have proven valuable for the prevention of primary or recurrent pulmonary embolism in selected patients with or at high risk for venous thromboembolic disease. Their use has become commonplace, and the numbers implanted increase annually. During the last 3 years, in the United States, the percentage of annually placed optional filters, i.e., filters than can remain as permanent filters or potentially be retrieved, has consistently exceeded that of permanent filters. In parallel, the complications of long- or short-term filtration have become increasingly evident to physicians, regulatory agencies, and the public. Most filter removals are uneventful, with a high degree of success. When routine filter-retrieval techniques prove unsuccessful, progressively more advanced tools and skill sets must be used to enhance filter-retrieval success. These techniques should be used with caution to avoid damage to the filter or cava during IVC retrieval. This review describes the complex techniques for filter retrieval, including use of additional snares, guidewires, angioplasty balloons, and mechanical and thermal approaches as well as illustrates their specific application.

Iliescu, Bogdan; Haskal, Ziv J., E-mail: ziv2@mac.com [University of Maryland School of Medicine, Division of Vascular and Interventional Radiology (United States)

2012-08-15

85

Advanced imaging techniques for the detection of breast cancer.  

PubMed

Mammography is the only breast imaging examination that has been shown to reduce breast cancer mortality. Population-based sensitivity is 75% to 80%, but sensitivity in high-risk women with dense breasts is only in the range of 50%. Breast ultrasound and contrast-enhanced breast magnetic resonance imaging (MRI) have become additional standard modalities used in the diagnosis of breast cancer. In high-risk women, ultrasound is known to detect approximately four additional cancers per 1,000 women. MRI is exquisitely sensitive for the detection of breast cancer. In high-risk women, it finds an additional four to five cancers per 100 women. However, both ultrasound and MRI are also known to lead to a large number of additional benign biopsies and short-term follow-up examinations. Many new breast imaging tools have improved and are being developed to improve on our current ability to diagnose early-stage breast cancer. These can be divided into two groups. The first group is those that are advances in current techniques, which include digital breast tomosynthesis and contrast-enhanced mammography and ultrasound with elastography or microbubbles. The other group includes new breast imaging platforms such as breast computed tomography (CT) scanning and radionuclide breast imaging. These are exciting advances. However, in this era of cost and radiation containment, it is imperative to look at all of them objectively to see which will provide clinically relevant additional information. PMID:24451711

Jochelson, Maxine

2012-01-01

86

Multiple advanced surgical techniques to treat acquired seminal duct obstruction  

PubMed Central

The aim of this study was to evaluate the outcomes of multiple advanced surgical treatments (i.e. microsurgery, laparoscopic surgery and endoscopic surgery) for acquired obstructive azoospermia. We analyzed the surgical outcomes of 51 patients with suspected acquired obstructive azoospermia consecutively who enrolled at our center between January 2009 and May 2013. Modified vasoepididymostomy, laparoscopically assisted vasovasostomy and transurethral incision of the ejaculatory duct with holmium laser were chosen and performed based on the different obstruction sites. The mean postoperative follow-up time was 22 months (range: 9 months to 52 months). Semen analyses were initiated at four postoperative weeks, followed by trimonthly (months 3, 6, 9 and 12) semen analyses, until no sperm was found at 12 months or until pregnancy was achieved. Patency was defined as >10,000 sperm ml?1 of semen. The obstruction sites, postoperative patency and natural pregnancy rate were recorded. Of 51 patients, 47 underwent bilateral or unilateral surgical reconstruction; the other four patients were unable to be treated with surgical reconstruction because of pelvic vas or intratesticular tubules obstruction. The reconstruction rate was 92.2% (47/51), and the patency rate and natural pregnancy rate were 89.4% (42/47) and 38.1% (16/42), respectively. No severe complications were observed. Using multiple advanced surgical techniques, more extensive range of seminal duct obstruction was accessible and correctable; thus, a favorable patency and pregnancy rate can be achieved. PMID:25337841

Jiang, Hong-Tao; Yuan, Qian; Liu, Yu; Liu, Zeng-Qin; Zhou, Zhen-Yu; Xiao, Ke-Feng; Yang, Jiang-Gen

2014-01-01

87

New techniques for sub-doppler spectroscopy of molecular ions  

NASA Astrophysics Data System (ADS)

This thesis details research in developing new methods for performing high-resolution sub-Doppler spec- troscopy of molecular ions in the laboratory. Molecular ions are of interest to a variety of fields, from astrochemistry to fundamental physics to the study of chemical reactive intermediates. The limiting factor in developing a deeper understanding of many ion systems is the quality of the available laboratory spectra. Traditional techniques for high-resolution spectroscopy of ions are limited by two factors: the precision is often limited by the Doppler-broadened linewidths of the observed spectra, and the accuracy is typically limited by the laser frequency calibration. Two new techniques are described in this thesis: cavity enhanced velocity modulation spectroscopy (CEVMS) and ion beam spectroscopy. Each of these techniques was first implemented in the near-infrared spectral region using a titanium sapphire laser, and was then extended into the mid-infrared, using an optical parametric oscillator (OPO) for CEVMS and difference frequency generation (DFG) for the ion beam. Both of these techniques allow for sub-Doppler resolution to signifi- cantly improve the precision beyond what was possible with traditional ion spectroscopy, and because both techniques are based on direct absorption spectroscopy, they require nothing of the ion of interest other than an allowed transition within the tuning range of the laser used, making them applicable to a wide variety of ions. The lasers used with both of these techniques have been referenced with an optical frequency comb for sub-megahertz absolute calibration accuracy of linecenters, which is a significant improvement beyond the 20-200 MHz accuracy that was typical of ion spectroscopy before the work presented in this thesis.

Siller, Brian M.

88

Recent Advances in Seismic Wavefront Tracking Techniques and Their Applications  

NASA Astrophysics Data System (ADS)

In observational seismology, wavefront tracking techniques are becoming increasingly popular as a means of predicting two point traveltimes and their associated paths. Possible applications include reflection migration, earthquake relocation and seismic tomography at a wide variety of scales. Compared with traditional ray based techniques such as shooting and bending, wavefront tracking has the advantage of locating traveltimes between the source and every point in the medium; in many cases, improved efficiency and robustness; and greater potential for tracking multiple arrivals. In this presentation, two wavefront tracking techniques will be considered: the so-called Fast Marching Method (FMM), and a wavefront construction (WFC) scheme. Over the last several years, FMM has become a mature technique in seismology, with a number of improvements to the underlying theory and the release of software tools that allow it to be used in a variety of applications. At its core, FMM is a grid based solver that implicitly tracks a propagating wavefront by seeking finite difference solutions to the eikonal equation along an evolving narrow band. Recent developments include the use of source grid refinement to improve accuracy, the introduction of a multi-stage scheme to allow reflections and refractions to be tracked in layered media, and extension to spherical coordinates. Implementation of these ideas has led to a number of different applications, including teleseismic tomography, wide-angle reflection and refraction tomography, earthquake relocation, and ambient noise imaging using surface waves. The WFC scheme represents the wavefront surface as a set of points in 6-D phase space; these points are advanced in time using local initial value ray tracing in order to form a sequence of wavefront surfaces that fill the model volume. Surface refinement and simplification techniques inspired by recent developments in computer graphics are used to maintain a fixed density of nodes as the wavefront evolves. In addition to being computationally efficient and robust, the new WFC scheme can also be used to track multi-arrivals in complex media, and thus may lead to new developments in seismic tomography.

Sambridge, M.; Rawlinson, N.; Hauser, J.

2007-12-01

89

Recent advances in capillary electrochromatography using molecularly imprinted polymers.  

PubMed

There is an increased and continuous need for developing new methods for the separation and quantification of an increasing number of analytes in the environmental, pharmaceutical, pharmacological, and toxicological sciences. CEC is still withholding its popularity, representing a viable alternative to the more conventional techniques (HPLC, GC) due to the numerous advantages, such as, low sample/reagent volumes, high separation efficiencies, hybrid separation principle, etc. One particular promising direction in CEC is the use of molecularly imprinted polymers (MIPs) as stationary phases. They are usually immobilized in the capillary column as a continuous polymeric monolith or as a thin polymer coating attached to the capillary's inner wall. Another emerging trend is the use of MIPs in the form of nanoparticles as a pseudostationary phase. This review discusses the recent developments (2011-2013) in finding the optimal polymerization mixture and the suitable MIP format that should be employed in CEC separations. The most important applications of MIPs in CEC technique are also highlighted. PMID:25042043

Iacob, Bogdan-Cezar; Bodoki, Ede; Oprean, Radu

2014-10-01

90

Sculpting 3D worlds with music: advanced texturing techniques  

NASA Astrophysics Data System (ADS)

Sound within the virtual environment is often considered to be secondary to the graphics. In a typical scenario, either audio cues are locally associated with specific 3D objects or a general aural ambiance is supplied in order to alleviate the sterility of an artificial experience. This paper discusses a completely different approach, in which cues are extracted from live or recorded music in order to create geometry and control object behaviors within a computer- generated environment. Advanced texturing techniques used to generate complex stereoscopic images are also discussed. By analyzing music for standard audio characteristics such as rhythm and frequency, information is extracted and repackaged for processing. With the Soundsculpt Toolkit, this data is mapped onto individual objects within the virtual environment, along with one or more predetermined behaviors. Mapping decisions are implemented with a user definable schedule and are based on the aesthetic requirements of directors and designers. This provides for visually active, immersive environments in which virtual objects behave in real-time correlation with the music. The resulting music-driven virtual reality opens up several possibilities for new types of artistic and entertainment experiences, such as fully immersive 3D `music videos' and interactive landscapes for live performance.

Greuel, Christian; Bolas, Mark T.; Bolas, Niko; McDowall, Ian E.

1996-04-01

91

Dissecting cell adhesion architecture using advanced imaging techniques  

PubMed Central

Cell adhesion to extracellular matrix proteins or to other cells is essential for the control of embryonic development, tissue integrity, immune function and wound healing. Adhesions are tightly spatially regulated structures containing over one hundred different proteins that coordinate both dynamics and signaling events at these sites. Extensive biochemical and morphological analysis of adhesion types over the past three decades has greatly improved understanding of individual protein contributions to adhesion signaling and, in some cases, dynamics. However, it is becoming increasingly clear that these diverse macromolecular complexes contain a variety of protein sub-networks, as well as distinct sub-domains that likely play important roles in regulating adhesion behavior. Until recently, resolving these structures, which are often less than a micron in size, was hampered by the limitations of conventional light microscopy. However, recent advances in optical techniques and imaging methods have revealed exciting insight into the intricate control of adhesion structure and assembly. Here we provide an overview of the recent data arising from such studies of cell:matrix and cell:cell contact and an overview of the imaging strategies that have been applied to study the intricacies and hierarchy of proteins within adhesions. PMID:21785274

Morton, Penny E

2011-01-01

92

REVIEW ARTICLE: Emission measurement techniques for advanced powertrains  

NASA Astrophysics Data System (ADS)

Recent developments in high-efficiency low-emission powertrains require the emission measurement technologies to be able to detect regulated and unregulated compounds with very high sensitivity and a fast response. For example, levels of a variety of nitrogen compounds and sulphur compounds should be analysed in real time in order to develop aftertreatment systems to decrease emission of NOx for the lean burning powertrains. Also, real-time information on the emission of particulate matter for the transient operation of diesel engines and direct injection gasoline engines is invaluable. The present paper reviews newly introduced instrumentation for such emission measurement that is demanded for the developments in advanced powertrain systems. They include Fourier transform infrared spectroscopy, mass spectrometry and fast response flame ionization detection. In addition, demands and applications of the fuel reformer developments for fuel cell electric vehicles are discussed. Besides the detection methodologies, sample handling techniques for the measurement of concentrations emitted from low emission vehicles for which the concentrations of the pollutants are significantly lower than the concentrations present in ambient air, are also described.

Adachi, Masayuki

2000-10-01

93

Double-Edge Molecular Technique for Doppler Lidar Wind Measurement  

NASA Technical Reports Server (NTRS)

The double-edge lidar technique for measuring the wind using molecular backscatter is described. Two high spectral resolution edge filters are located in the wings of the Rayleigh-Brillouin profile. This doubles the signal change per unit Doppler shift, the sensitivity, and gives nearly a factor of two improvement in measurement accuracy. The use of a crossover region is described where the sensitivity of a molecular and aerosol-based measurement are equal. This desensitizes the molecular measurement to the effects of aerosol scattering over a frequency range of +/- 100 m/s. We give methods for correcting for short-term frequency jitter and drift using a laser reference frequency measurement and methods for long-term frequency correction using a servo control system. The effects of Rayleigh-Brillouin scattering on the measurement are shown to be significant and are included in the analysis. Simulations for a conical scanning satellite-based lidar at 355 nm show an accuracy of 2-3 m/s for altitudes of 2 to 15 km for a 1 km vertical resolution, a satellite altitude of 400 km and a 200 km x 200 km spatial resolution. Results of ground based wind measurements are presented.

Flesia, Cristina; Korb, C. Laurence

1998-01-01

94

Constant-Pressure Molecular Dynamics Techniques Applied to Complex Molecular Systems and Solvated Proteins  

Microsoft Academic Search

To assess the feasibility of high-pressure simulation of biomolecular systems, we discuss some practical aspects of molecular dynamics simulation techniques at constant pressure and temperature. We compare the extended Lagrangian (EL) method, initially developed by Andersen1 for sampling from well-defined statistical mechanical ensembles, with the method by Berendsen et al.,2 where temperature and\\/or pressure are kept constant by weakly coupling

Emanuele Paci; Massimo Marchi

1996-01-01

95

Weldability and joining techniques for advanced fossil energy system alloys  

SciTech Connect

The efforts represent the concerns for the basic understanding of the weldability and fabricability of the advanced high temperature alloys so necessary to affect increases in the efficiency of the next generation Fossil Energy Power Plants. The effort was divided into three tasks with the first effort dealing with the welding and fabrication behavior of 310HCbN (HR3C), the second task details the studies aimed at understanding the weldability of a newly developed 310TaN high temperature stainless (a modification of 310 stainless) and Task 3 addressed the cladding of austenitic tubing with Iron-Aluminide using the GTAW process. Task 1 consisted of microstructural studies on 310HCbN and the development of a Tube Weldability test which has applications to production welding techniques as well as laboratory weldability assessments. In addition, the evaluation of ex-service 310HCbN which showed fireside erosion and cracking at the attachment weld locations was conducted. Task 2 addressed the behavior of the newly developed 310 TaN modification of standard 310 stainless steel and showed that the weldability was excellent and that the sensitization potential was minimal for normal welding and fabrication conditions. The microstructural evolution during elevated temperature testing was characterized and the second phase particles evolved upon aging were identified. Task 3 details the investigation undertaken to clad 310HCbN tubing with Iron Aluminide and developed welding conditions necessary to provide a crack free cladding. The work showed that both a preheat and a post-heat was necessary for crack free deposits and the effect of a third element on the cracking potential was defined together with the effect of the aluminum level for optimum weldability.

Lundin, C.D.; Qiao, C.Y.P.; Liu, W.; Yang, D.; Zhou, G.; Morrison, M. [Univ. of Tennessee, Knoxville, TN (United States)

1998-05-01

96

Integrating advanced materials simulation techniques into an automated data analysis workflow at the Spallation Neutron Source  

SciTech Connect

This presentation will review developments on the integration of advanced modeling and simulation techniques into the analysis step of experimental data obtained at the Spallation Neutron Source. A workflow framework for the purpose of refining molecular mechanics force-fields against quasi-elastic neutron scattering data is presented. The workflow combines software components to submit model simulations to remote high performance computers, a message broker interface for communications between the optimizer engine and the simulation production step, and tools to convolve the simulated data with the experimental resolution. A test application shows the correction to a popular fixed-charge water model in order to account polarization effects due to the presence of solvated ions. Future enhancements to the refinement workflow are discussed. This work is funded through the DOE Center for Accelerating Materials Modeling.

Borreguero Calvo, Jose M [ORNL] [ORNL; Campbell, Stuart I [ORNL] [ORNL; Delaire, Olivier A [ORNL] [ORNL; Doucet, Mathieu [ORNL] [ORNL; Goswami, Monojoy [ORNL] [ORNL; Hagen, Mark E [ORNL] [ORNL; Lynch, Vickie E [ORNL] [ORNL; Proffen, Thomas E [ORNL] [ORNL; Ren, Shelly [ORNL] [ORNL; Savici, Andrei T [ORNL] [ORNL; Sumpter, Bobby G [ORNL] [ORNL

2014-01-01

97

Recent advances in molecular recognition based on nanoengineered platforms.  

PubMed

Nanoparticles and nanoengineered platforms have great potential for technologies involving biomoleuclar detection or cell-related biosensing, and have provided effective chemical interfaces for molecular recognition. Typically, chemists work on the modification of synthetic polymers or macromolecules, which they link to the nanoparticles by covalent or noncovalent approaches. The motivation for chemical modification is to enhance the selectivity and sensitivity, and to improve the biocompatibility for the in vivo applications. In this Account, we present recent advances in the development and application of chemical interfaces for molecular recognition for nanoparticles and nanoengineered platforms, in particular single-walled carbon nanotubes (SWNTs). We discuss emerging approaches for recognizing small molecules, glycosylated proteins, and serum biomarkers. For example, we compare and discuss detection methods for ATP, NO, H2O2, and monosaccharides for recent nanomaterials. Fluorometric detection appears to have great potential for quantifying concentration gradients and determining their location in living cells. For macromolecular detection, new methods for glycoprofiling using such interfaces appear promising, and benefit specifically from the potential elimination of cumbersome labeling and liberation steps during conventional analysis of glycans, augmenting the currently used mass spectrometry (MS), capillary electrophoresis (CE), and liquid chromatography (LC) methods. In particular, we demonstrated the great potential of fluorescent SWNTs for glycan-lectin interactions sensing. In this case, SWNTs are noncovalently functionalized to introduce a chelated nickel group. This group provides a docking site for the His-tagged lectin and acts as the signal modulator. As the nickel proximity to the SWNT surface changes, the fluorescent signal is increased or attenuated. When a free glycan or glycosylated probe interacts with the lectin, the signal increases and they are able to obtain loading curves similar to surface plasmon resonance measurements. They demonstrate the sensitivity and specificity of this platform with two higher-affined glycan-lectin pairs: fucose (Fuc) to PA-IIL and N-acetylglucosamine (GlcNAc) to GafD. Lastly, we discuss how developments in protein biomarker detection in general are benefiting specifically from label-free molecular recognition. Electrical field effect transistors, chemi-resistive and fluorometric nanosensors based on various nanomaterials have demonstrated substantial progress in recent years in addressing this challenging problem. In this Account, we compare the balance between sensitivity, selectivity, and nonspecific adsorption for various applications. In particular, our group has utilized SWNTs as fluorescence sensors for label-free protein-protein interaction measurements. In this assay, we have encapsulated each nanotube in a biocompatible polymer, chitosan, which has been further modified to conjugate nitrilotriacetic acid (NTA) groups. After Ni(2+) chelation, NTA Ni(2+) complexes bind to his-tagged proteins, resulting in a local environment change of the SWNT array, leading to optical fluorescence modulation with detection limit down to 100 nM. We have further engineered the platform to monitor single protein binding events, with an even lower detection limit down to 10 pM. PMID:24467652

Mu, Bin; Zhang, Jingqing; McNicholas, Thomas P; Reuel, Nigel F; Kruss, Sebastian; Strano, Michael S

2014-04-15

98

Investigation of joining techniques for advanced austenitic alloys  

SciTech Connect

Modified Alloys 316 and 800H, designed for high temperature service, have been developed at Oak Ridge National Laboratory. Assessment of the weldability of the advanced austenitic alloys has been conducted at the University of Tennessee. Four aspects of weldability of the advanced austenitic alloys were included in the investigation.

Lundin, C.D.; Qiao, C.Y.P.; Kikuchi, Y.; Shi, C.; Gill, T.P.S.

1991-05-01

99

PDE Estimation Techniques for Advanced Battery Management Systems -Part II: SOH Identification  

E-print Network

PDE Estimation Techniques for Advanced Battery Management Systems - Part II: SOH Identification S and Reinvestment Act (ARRA) of 2009 [3]. As such, battery management systems within these advanced transportation vehi- cles and renewable energy resources is battery energy storage. Advanced battery systems represent

Krstic, Miroslav

100

PDE Estimation Techniques for Advanced Battery Management Systems -Part I: SOC Estimation  

E-print Network

PDE Estimation Techniques for Advanced Battery Management Systems - Part I: SOC Estimation S. J (ARRA) of 2009. As such, battery management systems within these advanced transportation and energy- cles and renewable energy resources is battery energy storage. Advanced battery systems represent

Krstic, Miroslav

101

Recent advances in radar instrumentation and techniques for studies of the mesosphere, stratosphere, and troposphere  

Microsoft Academic Search

The last few years have seen several significant advances in mesosphere- stratosphere-troposphere (MST) radar studies. This is true with respect to studies ranging from MF through VHF and up to UHF. These advances have been in each of the areas of equipment, techniques, and general radar theory. In this short paper we will highlight some of these advances and discuss

W. K. Hocking

1997-01-01

102

Surgical technique: new advancements for expanding indications and safety  

Microsoft Academic Search

The technical issues discussed herein represent part of the panorama of innovative approaches proposed for the surgical treatment\\u000a of hepatocellular carcinoma (HCC); in particular, the attention is focused on the recent advances in the field of planning\\u000a the surgical strategy and performing liver dissection via ultrasound guidance. It is described how recent technical \\u000a advances have allowed the range of scenarios

Guido Torzilli

2010-01-01

103

Ayman F. HabibAdvanced Photogrammetric Techniques LiDAR Mapping  

E-print Network

Ayman F. HabibAdvanced Photogrammetric Techniques 1 LiDAR Mapping Chapter 4 #12;Ayman F. HabibAdvanced Photogrammetric Techniques 2 Overview · Passive versus active sensors · LASER principles · LiDAR principles · LiDAR equation · Error sources (systematic and random errors) · Quality assurance for LiDAR systems · Quality

Habib, Ayman

104

Advanced Photogrammetric Techniques Ayman F. Habib Photogrammetric & LiDAR Data  

E-print Network

Advanced Photogrammetric Techniques Ayman F. Habib 1 Photogrammetric & LiDAR Data Integration Chapter 5 #12;Advanced Photogrammetric Techniques Ayman F. Habib 2 Overview · Photogrammetric and LiDAR data: why? · Photogrammetric and LiDAR data: How? ­ Registration (co-alignment) paradigm ­ Experimental

Habib, Ayman

105

How Molecular Structure Affects Mechanical Properties of an Advanced Polymer  

NASA Technical Reports Server (NTRS)

density was performed over a range of temperatures below the glass transition temperature. The physical characterization, elastic properties and notched tensile strength all as a function of molecular weight and test temperature were determined. For the uncrosslinked SI material, it was shown that notched tensile strength is a strong function of both temperature and molecular weight, whereas stiffness is only a strong function of temperature. For the crosslinked PETI-SI material, it was shown that the effect of crosslinking significantly enhances the mechanical performance of the low molecular weight material; comparable to that exhibited by the high molecular weight material.

Nicholson, Lee M.; Whitley, Karen S.; Gates, Thomas S.; Hinkley, Jeffrey A.

2000-01-01

106

Advanced Millimeter-Wave Security Portal Imaging Techniques  

SciTech Connect

Millimeter-wave imaging is rapidly gaining acceptance for passenger screening at airports and other secured facilities. This paper details a number of techniques developed over the last several years including novel image reconstruction and display techniques, polarimetric imaging techniques, array switching schemes, as well as high frequency high bandwidth techniques. Implementation of some of these methods will increase the cost and complexity of the mm-wave security portal imaging systems. RF photonic methods may provide new solutions to the design and development of the sequentially switched linear mm-wave arrays that are the key element in the mm-wave portal imaging systems.

Sheen, David M.; Bernacki, Bruce E.; McMakin, Douglas L.

2012-04-01

107

Narcolepsy and familial advanced sleep-phase syndrome: molecular genetics of sleep disorders  

Microsoft Academic Search

Sleep disorders are very prevalent and represent an emerging worldwide epidemic. However, research into the molecular genetics of sleep disorders remains surprisingly one of the least active fields. Nevertheless, rapid progress is being made in several prototypical disorders, leading recently to the identification of the molecular pathways underlying narcolepsy and familial advanced sleep-phase syndrome. Since the first reports of spontaneous

Mehdi Tafti; Yves Dauvilliers; Sebastiaan Overeem

2007-01-01

108

Advances Towards Synthetic Machines at the Molecular and Nanoscale Level  

PubMed Central

The fabrication of increasingly smaller machines to the nanometer scale can be achieved by either a “top-down” or “bottom-up” approach. While the former is reaching its limits of resolution, the latter is showing promise for the assembly of molecular components, in a comparable approach to natural systems, to produce functioning ensembles in a controlled and predetermined manner. In this review we focus on recent progress in molecular systems that act as molecular machine prototypes such as switches, motors, vehicles and logic operators. PMID:20640163

Konstas, Kristina; Langford, Steven J.; Latter, Melissa J.

2010-01-01

109

Advanced NDE techniques for quantitative characterization of aircraft  

NASA Technical Reports Server (NTRS)

Recent advances in nondestructive evaluation (NDE) at NASA Langley Research Center and their applications that have resulted in quantitative assessment of material properties based on thermal and ultrasonic measurements are reviewed. Specific applications include ultrasonic determination of bolt tension, ultrasonic and thermal characterization of bonded layered structures, characterization of composite materials, and disbonds in aircraft skins.

Heyman, Joseph S.; Winfree, William P.

1990-01-01

110

Magnetorheological technique and application in advanced Intelligent artificial Limb  

Microsoft Academic Search

the research survey of magnetorheological dampers has been introduced in the paper, the mechanics modeling of magnetorheological dampers has been found based on intelligent artificial limb as well as its optimized installation position in artificial limb and the control principles of knee joints. The intelligent following can be carried out by advanced intelligent limb according to the gait of healthy

Fu Li; Xie Hualong; Xu Xinhe; Yu Mei-xiang

2008-01-01

111

Development and Deployment of an Advanced Wind Forecasting Technique  

E-print Network

in Porto) Power Systems Unit Porto, Portugal Industry Partners Horizon Wind Energy, LLC Midwest Independent System Operator Sponsor U.S. Department of Energy Wind and Hydropower Technologies Program #12;Page 2 1 the output of advanced wind energy forecasts into decision support models for wind power plant and power

Kemner, Ken

112

[Molecular techniques applied in species identification of Toxocara].  

PubMed

Toxocarosis is still an important and actual problem in human medicine. It can manifest as visceral (VLM), ocular (OLM) or covert (CT) larva migrans syndroms. Complicated life cycle of Toxocara, lack of easy and practical methods of species differentiation of the adult nematode and embarrassing in recognition of the infection in definitive hosts create difficulties in fighting with the infection. Although studies on human toxocarosis have been continued for over 50 years there is no conclusive answer, which of species--T. canis or T. cati constitutes a greater risk of transmission of the nematode to man. Neither blood serological examinations nor microscopic observations of the morphological features of the nematode give the satisfied answer on the question. Since the 90-ths molecular methods were developed for species identification and became useful tools being widely applied in parasitological diagnosis. This paper cover the survey of methods of DNA analyses used for identification of Toxocara species. The review may be helpful for researchers focused on Toxocara and toxocarosis as well as on detection of new species. The following techniques are described: PCR (Polymerase Chain Reaction), RFLP (Restriction Fragment Length Polymorphism), RAPD (Random Amplified Polymorphic DNA) and SSCP (Single Strand Conformation Polymorphism). PMID:17007334

Fogt, Renata

2006-01-01

113

Improving human forensics through advances in genetics, genomics and molecular biology.  

PubMed

Forensic DNA profiling currently allows the identification of persons already known to investigating authorities. Recent advances have produced new types of genetic markers with the potential to overcome some important limitations of current DNA profiling methods. Moreover, other developments are enabling completely new kinds of forensically relevant information to be extracted from biological samples. These include new molecular approaches for finding individuals previously unknown to investigators, and new molecular methods to support links between forensic sample donors and criminal acts. Such advances in genetics, genomics and molecular biology are likely to improve human forensic case work in the near future. PMID:21331090

Kayser, Manfred; de Knijff, Peter

2011-03-01

114

Advances in nanomagnetism via X-ray techniques  

NASA Astrophysics Data System (ADS)

This report examines the current status and the future directions of the field of nanomagnetism and assesses the ability of hard X-ray synchrotron facilities to provide new capabilities for making advances in this field. The report first identifies major research challenges that lie ahead in three broadly defined subfields of nanomagnetism: confined systems, clusters and complex oxides. It then examines the relevant experimental capabilities that are currently available at hard X-ray synchrotron light sources, using the Advanced Photon Source (APS) at Argonne as an example. Finally, recommendations are made for future development in X-ray facilities that will enhance the study of nanomagnetism, including new experimental directions, modifications that would enable in situ sample preparation, and measurements at high magnetic fields and/or low temperatures. In particular, in situ sample preparation is of high priority in many experiments, especially those in the area of surface magnetism.

Srajer, G.; Lewis, L. H.; Bader, S. D.; Epstein, A. J.; Fadley, C. S.; Fullerton, E. E.; Hoffmann, A.; Kortright, J. B.; Krishnan, Kannan M.; Majetich, S. A.; Rahman, T. S.; Ross, C. A.; Salamon, M. B.; Schuller, I. K.; Schulthess, T. C.; Sun, J. Z.

2006-12-01

115

Development of Advanced In-Situ Techniques for Chemistry Monitoring and Corrosion Mitigation in SCWO Environments  

SciTech Connect

This project is developing sensing technologies and corrosion monitoring techniques for use in super critical water oxidation (SCWO) systems to reduce the volume of mixed low-level nuclear waste by oxidizing organic components in a closed cycle system where CO2 and other gaseous oxides are produced, leaving the radioactive elements concentrated in ash. The technique uses water at supercritical temperatures under highly oxidized conditions by maintaining a high fugacity of molecular oxygen in the system, which causes high corrosion rates of even the most corrosive resistant reactor materials. This project significantly addresses the high corrosion shortcoming through development of (a) advanced electrodes and sensors for in situ potentiometric monitoring of pH in high subcritical and supercritical aqueous solutions, (b) an approach for evaluating the association constants for 1-1 aqueous electrolytes using a flow-through electrochemical thermocell; (c) an electrochemical noise sensor for the in situ measurement of corrosion rate in subcritical and supercritical aqueous systems; (d) a model for estimating the effect of pressure on reaction rates, including corrosion reactions, in high subcritical and supercritical aqueous systems. The project achieved all objectives, except for installing some of the sensors into a fully operating SCWO system.

Macdonald, D. D.; Lvov, S. N.

2000-03-31

116

A Coupled Meshless Technique/Molecular Dynamics Approach for Deformation Characterization of Mono-crystalline Metal  

SciTech Connect

This paper presents a multiscale study using the coupled Meshless technique/Molecular Dynamics (M{sup 2}) for exploring the deformation mechanism of mono-crystalline metal (focus on copper) under uniaxial tension. In M{sup 2}, an advanced transition algorithm using transition particles is employed to ensure the compatibility of both displacements and their gradients, and an effective local quasi-continuum approach is also applied to obtain the equivalent continuum strain energy density based on the atomistic potentials and Cauchy-Born rule. The key parameters used in M{sup 2} are firstly investigated using a benchmark problem. Then, M{sup 2} is applied to the multiscale simulation for a mono-crystalline copper bar. It has found that the mono-crystalline copper has very good elongation property, and the ultimate strength and Young's modulus are much higher than those obtained in macro-scale.

Gu, Y. T.; Yarlagadda, Prasad K. D. V. [School of Engineering Systems, Queensland Uni. of Technology, GPO Box 2434, Brisbane, QLD 4001 (Australia)

2010-05-21

117

ADVANCED NANOIMPRINT TECHNIQUE FOR MULTILAYER STRUCTURES AND FUNCTIONAL POLYMER APPLICATIONS  

E-print Network

impact on the applications of soft materials such as polymers including functional polymers in micro- and nanofabricated devices and systems. Although NIL technique is developing rapidly in recent years, there are still issues that need to be addressed...

Park, Hyunsoo

2010-07-14

118

Backscattered Electron Microscopy as an Advanced Technique in Petrography.  

ERIC Educational Resources Information Center

Three uses of this method with sandstone, desert varnish, and granite weathering are described. Background information on this technique is provided. Advantages of this type of microscopy are stressed. (CW)

Krinsley, David Henry; Manley, Curtis Robert

1989-01-01

119

Recent advances in the molecular pathophysiology of atrial fibrillation  

PubMed Central

Atrial fibrillation (AF) is an extremely common cardiac rhythm disorder that causes substantial morbidity and contributes to mortality. The mechanisms underlying AF are complex, involving both increased spontaneous ectopic firing of atrial cells and impulse reentry through atrial tissue. Over the past ten years, there has been enormous progress in understanding the underlying molecular pathobiology. This article reviews the basic mechanisms and molecular processes causing AF. We discuss the ways in which cardiac disease states, extracardiac factors, and abnormal genetic control lead to the arrhythmia. We conclude with a discussion of the potential therapeutic implications that might arise from an improved mechanistic understanding. PMID:21804195

Wakili, Reza; Voigt, Niels; Kaab, Stefan; Dobrev, Dobromir; Nattel, Stanley

2011-01-01

120

Recent advances in the molecular biology of metazoan polyamine transport  

PubMed Central

Very limited molecular knowledge exists about the identity and protein components of the ubiquitous polyamine transporters found in animal cells. However, a number of reports have been published over the last 5 years on potential candidates for metazoan polyamine permeases. We review the available evidence on these putative polyamine permeases, as well as establish a useful «identikit picture» of the general polyamine transport system, based on its properties as found in a wide spectrum of mammalian cells. Any molecular candidate encoding a putative «general» polyamine permease should fit that provided portrait. The current models proposed for the mechanism of polyamine internalization in mammalian cells are also briefly reviewed. PMID:21814785

Casero, R. A.; Soulet, D.

2013-01-01

121

Application of advanced coating techniques to rocket engine components  

NASA Technical Reports Server (NTRS)

The materials problem in the space shuttle main engine (SSME) is reviewed. Potential coatings and the method of their application for improved life of SSME components are discussed. A number of advanced coatings for turbine blade components and disks are being developed and tested in a multispecimen thermal fatigue fluidized bed facility at IIT Research Institute. This facility is capable of producing severe strains of the degree present in blades and disk components of the SSME. The potential coating systems and current efforts at IITRI being taken for life extension of the SSME components are summarized.

Verma, S. K.

1988-01-01

122

Brain development in preterm infants assessed using advanced MRI techniques.  

PubMed

Infants who are born preterm have a high incidence of neurocognitive and neurobehavioral abnormalities, which may be associated with impaired brain development. Advanced magnetic resonance imaging (MRI) approaches, such as diffusion MRI (d-MRI) and functional MRI (fMRI), provide objective and reproducible measures of brain development. Indices derived from d-MRI can be used to provide quantitative measures of preterm brain injury. Although fMRI of the neonatal brain is currently a research tool, future studies combining d-MRI and fMRI have the potential to assess the structural and functional properties of the developing brain and its response to injury. PMID:24524445

Tusor, Nora; Arichi, Tomoki; Counsell, Serena J; Edwards, A David

2014-03-01

123

Tumor Functional and Molecular Imaging Utilizing Ultrasound and Ultrasound-Mediated Optical Techniques  

PubMed Central

Tumor functional and molecular imaging has significantly contributed to cancer preclinical research and clinical applications. Among typical imaging modalities, ultrasonic and optical techniques are two commonly used methods; both share several common features such as cost efficiency, absence of ionizing radiation, relatively inexpensive contrast agents, and comparable maximum-imaging depth. Ultrasonic and optical techniques are also complementary in imaging resolution, molecular sensitivity, and imaging space (vascular and extravascular). The marriage between ultrasonic and optical techniques takes advantages of both techniques. This review introduces tumor functional and molecular imaging using microbubble-based ultrasound and ultrasound-mediated optical imaging techniques. PMID:23219728

Yuan, Baohong; Rychak, Joshua

2014-01-01

124

Benefits of advanced software techniques for mission planning systems  

NASA Technical Reports Server (NTRS)

The increasing complexity of modern spacecraft, and the stringent requirement for maximizing their mission return, call for a new generation of Mission Planning Systems (MPS). In this paper, we discuss the requirements for the Space Mission Planning and the benefits which can be expected from Artificial Intelligence techniques through examples of applications developed by Matra Marconi Space.

Gasquet, A.; Parrod, Y.; Desaintvincent, A.

1994-01-01

125

In Situ Techniques for Monitoring Electrochromism: An Advanced Laboratory Experiment  

ERIC Educational Resources Information Center

This experiment employs current technology to enhance and extend existing lab content. The basic principles of spectroscopic and electroanalytical techniques and their use in determining material properties are covered in some detail in many undergraduate chemistry programs. However, there are limited examples of laboratory experiments with in…

Saricayir, Hakan; Uce, Musa; Koca, Atif

2010-01-01

126

Advances in reduction techniques for tire contact problems  

NASA Technical Reports Server (NTRS)

Some recent developments in reduction techniques, as applied to predicting the tire contact response and evaluating the sensitivity coefficients of the different response quantities, are reviewed. The sensitivity coefficients measure the sensitivity of the contact response to variations in the geometric and material parameters of the tire. The tire is modeled using a two-dimensional laminated anisotropic shell theory with the effects of variation in geometric and material parameters, transverse shear deformation, and geometric nonlinearities included. The contact conditions are incorporated into the formulation by using a perturbed Lagrangian approach with the fundamental unknowns consisting of the stress resultants, the generalized displacements, and the Lagrange multipliers associated with the contact conditions. The elemental arrays are obtained by using a modified two-field, mixed variational principle. For the application of reduction techniques, the tire finite element model is partitioned into two regions. The first region consists of the nodes that are likely to come in contact with the pavement, and the second region includes all the remaining nodes. The reduction technique is used to significantly reduce the degrees of freedom in the second region. The effectiveness of the computational procedure is demonstrated by a numerical example of the frictionless contact response of the space shuttle nose-gear tire, inflated and pressed against a rigid flat surface. Also, the research topics which have high potential for enhancing the effectiveness of reduction techniques are outlined.

Noor, Ahmed K.

1995-01-01

127

Advancements in Drying Techniques for Food, Fiber, and Fuel  

Microsoft Academic Search

Removal of moisture from biological materials, popularly called drying, has numerous benefits, including ease of handling due to reduction in bulk, resulting in reduced handling costs. Moreover, drying prevents microbial growth and spoilage. Though different drying techniques share a common objective, conceptually they are different and require modification\\/adaptation based on the biomaterial that is dried. There have been significant scientific

Satyanarayan R. S. Dev; Vijaya G. S. Raghavan

2012-01-01

128

Advancements in Sensing and Perception using Structured Lighting Techniques: An LDRD Final Report.  

National Technical Information Service (NTIS)

This report summarizes the analytical and experimental efforts for the Laboratory Directed Research and Development (LDRD) project entitled 'Advancements in Sensing and Perception using Structured Lighting Techniques'. There is an ever-increasing need for...

D. D. Padilla, P. A. Davidson, J. J. Carlson, D. K. Novick

2005-01-01

129

Advanced data acquisition and display techniques for laser velocimetry  

NASA Technical Reports Server (NTRS)

The Basic Aerodynamics Research Tunnel (BART) has been equipped with state-of-the-art instrumentation for acquiring the data needed for code validation. This paper describes the three-component LDV and the workstation-based data-acquisition system (DAS) which has been developed for the BART. The DAS allows the use of automation and the quick integration of advanced instrumentation, while minimizing the software development time required between investigations. The paper also includes a description of a graphics software library developed to support the windowing environment of the DAS. The real-time displays generated using the graphics library help the researcher ensure the test is proceeding properly. The graphics library also supports the requirements of posttest data analysis. The use of the DAS and graphics libraries is illustrated by presenting examples of the real-time and postprocessing display graphics for LDV investigations.

Kjelgaard, Scott O.; Weston, Robert P.

1991-01-01

130

Advanced materials and techniques for fibre-optic sensing  

NASA Astrophysics Data System (ADS)

Fibre-optic monitoring systems came of age in about 1999 upon the emergence of the world's first significant commercialising company - a spin-out from the UK's collaborative MAST project. By using embedded fibre-optic technology, the MAST project successfully measured transient strain within high-performance composite yacht masts. Since then, applications have extended from smart composites into civil engineering, energy, military, aerospace, medicine and other sectors. Fibre-optic sensors come in various forms, and may be subject to embedment, retrofitting, and remote interrogation. The unique challenges presented by each implementation require careful scrutiny before widespread adoption can take place. Accordingly, various aspects of design and reliability are discussed spanning a range of representative technologies that include resonant microsilicon structures, MEMS, Bragg gratings, advanced forms of spectroscopy, and modern trends in nanotechnology. Keywords: Fibre-optic sensors, fibre Bragg gratings, MEMS, MOEMS, nanotechnology, plasmon.

Henderson, Philip J.

2014-06-01

131

Advancement in evaporation and calcination techniques for radwastes in India  

SciTech Connect

The evaporation technique is very effective in concentrating the volume of the liquid waste and separating the low-activity distillate. Water is removed in the vapor phase leaving behind nonvolatile radioactive content in the solution. Extensive experimental and theoretical investigations were carried out to optimize the design and operation of the evaporators. The experiments revealed that fouling of tubes and scaling increases at higher chemical concentrations. Therefore, for further removal of moisture, dehydration and denitration of the waste, calciners are used. The nitrates are water soluble and corrosive therefore, these are converted into solid oxides. The oxides are granular solids and chemically stable with good heat conductivity. This facilitates uniform mixing and good compatibility with glass matrix. In order to remove moisture, dehydrate, denitrify, and oxidize the heterogeneous waste into a granular product, various types of calcination techniques have been examined. A brief review of state of art and present state of technology is presented in this paper.

Pande, D.P. [Bhabha Atomic Research Center, Bombay (India)

1995-12-31

132

Recent advances in unique sample preparation techniques for bioanalysis.  

PubMed

The extraction and/or purification of drugs and medicines from biological matrices are important objectives in investigating their toxicological and pharmaceutical properties. Many widely used methods such as liquid-liquid extraction or SPE, used for extracting, purifying and enriching drugs and medicines found in biological materials, involve laborious, intensive and expensive preparatory procedures, and they require organic solvents that are toxic to both humans and the environment. Recent trends are focused on miniaturization, high-throughput and automation techniques. All the advantages and disadvantages of these techniques and devices in biological analysis are presented, and their applications in the extraction and/or purification of drugs and medicines from biological matrices are discussed in this review. PMID:23590474

Namera, Akira; Saito, Takeshi

2013-04-01

133

Advanced BEM for potential problems using spline techniques  

E-print Network

cylinder. The same technique is applied to a dielectric clad conducting cylinder. The scattered field and the radar cross section are calculated. The results from this approach are compared with the analytical solutions and the errors are estimated... Fields Fmm a Dielectric Coated Conducting Cylinder. . . D. Discussions VI CONCLUSIONS REFERENCES . VITA . 40 46 54 57 65 69 LIST OF TABLES TABLE Page 5-1 5-2 5-3 Convergence test . Errors ( Scattered H field ) . Errors ( Far- field...

Bi, Haifen

2012-06-07

134

Advanced processing and information extraction techniques applied to ERTS-1 MSS data  

NASA Technical Reports Server (NTRS)

Conventional automatic data processing and information extraction techniques fall short of providing the information required by the user in some applications. For those cases, advanced techniques are needed to permit the extraction of the necessary information. Advanced techniques are described and examples of their application to ERTS-1 MSS data are provided. The techniques are designed to help overcome problems in location, mensuration, and classification accuracies which result from geometric distortions of the ERTS MSS data, the relatively coarse resolution of the sensor, and variations in atmospheric state over the region to be surveyed. It is shown that each of these factors can seriously degrade one's ability to extract necessary information. Further, it is shown that advanced techniques can alleviate the effects of these factors.

Malila, W. A.; Nalepka, R. F.

1974-01-01

135

SJSU Information Support Services MSG101: Advanced Messaging Techniques info-support@sjsu.edu, 408-924-1530 Page 1  

E-print Network

SJSU Information Support Services MSG101: Advanced Messaging Techniques info-support@sjsu.edu, 408-924-1530 Page 1 MSG101: Advanced Messaging Techniques Overview This user guide demonstrates how to send messages ............................................................................................................................................................23 #12;SJSU Information Support Services MSG101: Advanced Messaging Techniques info

Su, Xiao

136

Advances in dental local anesthesia techniques and devices: An update  

PubMed Central

Although local anesthesia remains the backbone of pain control in dentistry, researches are going to seek new and better means of managing the pain. Most of the researches are focused on improvement in the area of anesthetic agents, delivery devices and technique involved. Newer technologies have been developed that can assist the dentist in providing enhanced pain relief with reduced injection pain and fewer adverse effects. This overview will enlighten the practicing dentists regarding newer devices and methods of rendering pain control comparing these with the earlier used ones on the basis of research and clinical studies available. PMID:24163548

Saxena, Payal; Gupta, Saurabh K.; Newaskar, Vilas; Chandra, Anil

2013-01-01

137

Advances in parameter estimation techniques applied to flexible structures  

NASA Technical Reports Server (NTRS)

In this work, various parameter estimation techniques are investigated in the context of structural system identification utilizing distributed parameter models and 'measured' time-domain data. Distributed parameter models are formulated using the PDEMOD software developed by Taylor. Enhancements made to PDEMOD for this work include the following: (1) a Wittrick-Williams based root solving algorithm; (2) a time simulation capability; and (3) various parameter estimation algorithms. The parameter estimations schemes will be contrasted using the NASA Mini-Mast as the focus structure.

Maben, Egbert; Zimmerman, David C.

1994-01-01

138

Magnetic resonance enterography in Crohn's disease: Standard and advanced techniques  

PubMed Central

Crohn’s disease (CD) is a chronic autoimmune disorder that affects mainly young people. The clinical management is based on the Crohn’s Disease Activity Index and especially on biologic parameters with or without additional endoscopic and imaging procedures, such as barium and computed tomography examinations. Recently, magnetic resonance (MR) imaging has been a promising diagnostic radiologic technique with lack of ionizing radiation, enabling superior tissue contrast resolution due to new pulse-sequence developments. Therefore, MR enterography has the potential to become the modality of choice for imaging the small bowel in CD patients. PMID:21160577

Kayhan, Arda; Oommen, Jacob; Dahi, Farid; Oto, Aytekin

2010-01-01

139

Advanced techniques in reliability model representation and solution  

NASA Technical Reports Server (NTRS)

The current tendency of flight control system designs is towards increased integration of applications and increased distribution of computational elements. The reliability analysis of such systems is difficult because subsystem interactions are increasingly interdependent. Researchers at NASA Langley Research Center have been working for several years to extend the capability of Markov modeling techniques to address these problems. This effort has been focused in the areas of increased model abstraction and increased computational capability. The reliability model generator (RMG) is a software tool that uses as input a graphical object-oriented block diagram of the system. RMG uses a failure-effects algorithm to produce the reliability model from the graphical description. The ASSURE software tool is a parallel processing program that uses the semi-Markov unreliability range evaluator (SURE) solution technique and the abstract semi-Markov specification interface to the SURE tool (ASSIST) modeling language. A failure modes-effects simulation is used by ASSURE. These tools were used to analyze a significant portion of a complex flight control system. The successful combination of the power of graphical representation, automated model generation, and parallel computation leads to the conclusion that distributed fault-tolerant system architectures can now be analyzed.

Palumbo, Daniel L.; Nicol, David M.

1992-01-01

140

Advances in dynamic relaxation techniques for nonlinear finite element analysis  

SciTech Connect

Traditionally, the finite element technique has been applied to static and steady-state problems using implicit methods. When nonlinearities exist, equilibrium iterations must be performed using Newton-Raphson or quasi-Newton techniques at each load level. In the presence of complex geometry, nonlinear material behavior, and large relative sliding of material interfaces, solutions using implicit methods often become intractable. A dynamic relaxation algorithm is developed for inclusion in finite element codes. The explicit nature of the method avoids large computer memory requirements and makes possible the solution of large-scale problems. The method described approaches the steady-state solution with no overshoot, a problem which has plagued researchers in the past. The method is included in a general nonlinear finite element code. A description of the method along with a number of new applications involving geometric and material nonlinearities are presented. They include: (1) nonlinear geometric cantilever plate; (2) moment-loaded nonlinear beam; and (3) creep of nuclear fuel channel assemblies.

Sauve, R.G.; Metzger, D.R. [Ontario Hydro Technologies, Toronto, Ontario (Canada)

1995-05-01

141

Recent Advances in Molecular Biology of Thyroid Cancer and Their Clinical Implications  

PubMed Central

Synopsis Thyroid cancer is the most common endocrine malignancy with a rapid rising incidence in recent years. Novel efficient management strategies are increasingly needed for this cancer. Remarkable advances have occurred in recent years in understanding the molecular biology of thyroid cancer. This is reflected in several major biological areas of thyroid cancer, including the molecular alterations for the loss of radioiodine avidity of thyroid cancer, the pathogenic role of the MAP kinase and PI3K/Akt pathways and their related genetic alterations, and the aberrant methylation of functionally important genes in thyroid tumorigenesis and pathogenesis. These exciting advances in molecular biology of thyroid cancer provide unprecedented opportunities for the development of molecular-based novel diagnostic, prognostic, and therapeutic strategies for this cancer. PMID:19040974

Xing, Mingzhao

2009-01-01

142

Advancing Neuroscience through Epigenetics: Molecular Mechanisms of Learning and Memory  

PubMed Central

Humans share 96% of our 30,000 genes with Chimpanzees. The 1,200 genes that differ appear at first glance insufficient to describe what makes us human and them apes. However, we are now discovering that the mechanisms that regulate how genes are expressed tell a much richer story than our DNA alone. Sections of our DNA are constantly being turned on or off, marked for easy access, or secluded and hidden away, all in response to on-going cellular activity. In the brain, neurons encode information – in effect memories – at the cellular level. Yet while memories may last a lifetime, neurons are dynamic structures. Every protein in the synapse undergoes some form of turnover, some with half-lives of only hours. How can a memory persist beyond the lifetimes of its constitutive molecular building blocks? Epigenetics – changes in gene expression that do not alter the underlying DNA sequence – may be the answer. In this article, epigenetic mechanisms including DNA methylation and acetylation or methylation of the histone proteins that package DNA are described in the context of animal learning. Through the interaction of these modifications a “histone code” is emerging wherein individual memories leave unique memory traces at the molecular level with distinct time courses. A better understanding of these mechanisms has implications for treatment of memory disorders caused by normal aging or diseases including schizophrenia, Alzheimer’s, depression, and drug addiction. PMID:21978007

Molfese, David L.

2011-01-01

143

Advanced guide coating techniques for Ultra-Cold Neutron transport  

NASA Astrophysics Data System (ADS)

The UCNA experiment utilizes Ultra-Cold Neutrons (UCN) to measure angular correlations in beta-decay. UCN are produced in a solid deuterium source and then transported to the experimental decay volume through a sequence of guide tubes. Requirements for the UCNA guides include smooth surfaces, high Fermi potentials, and also a very low depolarization probability per bounce. We review the UCNA guide system and the pulsed-laser deposition process we use to produce diamond like carbon (DLC) coatings on Cu and quartz tubes. Several improvements (magnetic field shaping of the plasma plume from the laser target and better guide mounting) over previous coating techniques will be described and their effectiveness presented.

Ding, Xinjian

2012-10-01

144

Advanced fabrication techniques for hydrogen-cooled engine structures  

NASA Technical Reports Server (NTRS)

Described is a program for development of coolant passage geometries, material systems, and joining processes that will produce long-life hydrogen-cooled structures for scramjet applications. Tests were performed to establish basic material properties, and samples constructed and evaluated to substantiate fabrication processes and inspection techniques. Results of the study show that the basic goal of increasing the life of hydrogen-cooled structures two orders of magnitude relative to that of the Hypersonic Research Engine can be reached with available means. Estimated life is 19000 cycles for the channels and 16000 cycles for pin-fin coolant passage configurations using Nickel 201. Additional research is required to establish the fatigue characteristics of dissimilar-metal coolant passages (Nickel 201/Inconel 718) and to investigate the embrittling effects of the hydrogen coolant.

Buchmann, O. A.; Arefian, V. V.; Warren, H. A.; Vuigner, A. A.; Pohlman, M. J.

1985-01-01

145

Electric Arc Locator in Photovoltaic Power Systems Using Advanced Signal Processing Techniques  

E-print Network

Electric Arc Locator in Photovoltaic Power Systems Using Advanced Signal Processing Techniques present two techniques for the localization of electric arcs produced in photovoltaic power systems. High AND RPA LOCALIZATION A. HOSA localization We model the system in figure 1 as an M equidistant receiver

Paris-Sud XI, Université de

146

4 Advanced Counting Techniques 4.1 Mathematical induction (weak induction)  

E-print Network

4 Advanced Counting Techniques 4.1 Mathematical induction (weak induction) This section presents another proof technique (besides direct, contrapositive and con- tradiction) 1. mathematical induction: Note that 1! = 1 is less than or equal to 11 = 1. The inductive step will continue now. (b) Inductive

Gera, Ralucca

147

Molecular targets of isothiocyanates in cancer: recent advances.  

PubMed

Cancer is a multistep process resulting in uncontrolled cell division. It results from aberrant signaling pathways that lead to uninhibited cell division and growth. Various recent epidemiological studies have indicated that consumption of cruciferous vegetables, such as garden cress, broccoli, etc., reduces the risk of cancer. Isothiocyanates (ITCs) have been identified as major active constituents of cruciferous vegetables. ITCs occur in plants as glucosinolate and can readily be derived by hydrolysis. Numerous mechanistic studies have demonstrated the anticancer effects of ITCs in various cancer types. ITCs suppress tumor growth by generating reactive oxygen species or by inducing cycle arrest leading to apoptosis. Based on the exciting outcomes of preclinical studies, few ITCs have advanced to the clinical phase. Available data from preclinical as well as available clinical studies suggest ITCs to be one of the promising anticancer agents available from natural sources. This is an up-to-date exhaustive review on the preventive and therapeutic effects of ITCs in cancer. PMID:24510468

Gupta, Parul; Kim, Bonglee; Kim, Sung-Hoon; Srivastava, Sanjay K

2014-08-01

148

Endoscopic therapy for early gastric cancer: Standard techniques and recent advances in ESD  

PubMed Central

The technique of endoscopic submucosal dissection (ESD) is now a well-known endoscopic therapy for early gastric cancer. ESD was introduced to resect large specimens of early gastric cancer in a single piece. ESD can provide precision of histologic diagnosis and can also reduce the recurrence rate. However, the drawback of ESD is its technical difficulty, and, consequently, it is associated with a high rate of complications, the need for advanced endoscopic techniques, and a lengthy procedure time. Various advances in the devices and techniques used for ESD have contributed to overcoming these drawbacks. PMID:24914364

Kume, Keiichiro

2014-01-01

149

Advanced Manufacturing Techniques Demonstrated for Fabricating Developmental Hardware  

NASA Technical Reports Server (NTRS)

NASA Glenn Research Center's Engineering Development Division has been working in support of innovative gas turbine engine systems under development by Glenn's Combustion Branch. These one-of-a-kind components require operation under extreme conditions. High-temperature ceramics were chosen for fabrication was because of the hostile operating environment. During the designing process, it became apparent that traditional machining techniques would not be adequate to produce the small, intricate features for the conceptual design, which was to be produced by stacking over a dozen thin layers with many small features that would then be aligned and bonded together into a one-piece unit. Instead of using traditional machining, we produced computer models in Pro/ENGINEER (Parametric Technology Corporation (PTC), Needham, MA) to the specifications of the research engineer. The computer models were exported in stereolithography standard (STL) format and used to produce full-size rapid prototype polymer models. These semi-opaque plastic models were used for visualization and design verification. The computer models also were exported in International Graphics Exchange Specification (IGES) format and sent to Glenn's Thermal/Fluids Design & Analysis Branch and Applied Structural Mechanics Branch for profiling heat transfer and mechanical strength analysis.

Redding, Chip

2004-01-01

150

Advances in low energy neutral atom imaging techniques  

SciTech Connect

Recently proposed low energy neutral atom (LENA) imaging techniques use a collisional process to convert the low energy neutrals into ions before detection. At low energies, collisional processes limit the angular resolution and conversion efficiencies of these devices. However, if the intense ultraviolet light background can be suppressed, direct LENA detection is possible. We present results from a series of experiments designed to develop a novel filtering structure based on free-standing transmission gratings. If the grating period is sufficiently small, free standing transmission gratings can be employed to substantially polarize ultraviolet (UV) light in the wavelength range 300 {Angstrom} to 1500 {Angstrom}. If a second grating is placed behind the first grating with its axis of polarization oriented at a right angle to the first`s, a substantial attenuation of UV radiation is achievable. ne neutrals will pass through the remaining open area of two gratings and be detected without UV background complications. We have obtained nominal 2000 {Angstrom} period (1000 {Angstrom} bars with 1000 {Angstrom} slits) free standing, gold transmission gratings and measured their UV and atomic transmission characteristics. The geometric factor of a LENA imager based on this technology is comparable to that of other proposed LENA imagers. In addition, this of imager does not distort the neutral trajectories, allowing for high angular resolution.

Scime, E.E.; Funsten, H.O.; McComas, D.J.; Moore, K.R. [Los Alamos National Lab., NM (United States); Gruntman, M. [University of Southern California, Los Angeles, CA (United States). Space Sciences Center

1993-05-01

151

Advances in low energy neutral atom imaging techniques  

SciTech Connect

Recently proposed low energy neutral atom (LENA) imaging techniques use a collisional process to convert the low energy neutrals into ions before detection. At low energies, collisional processes limit the angular resolution and conversion efficiencies of these devices. However, if the intense ultraviolet light background can be suppressed, direct LENA detection is possible. We present results from a series of experiments designed to develop a novel filtering structure based on free-standing transmission gratings. If the grating period is sufficiently small, free standing transmission gratings can be employed to substantially polarize ultraviolet (UV) light in the wavelength range 300 [Angstrom] to 1500 [Angstrom]. If a second grating is placed behind the first grating with its axis of polarization oriented at a right angle to the first's, a substantial attenuation of UV radiation is achievable. ne neutrals will pass through the remaining open area of two gratings and be detected without UV background complications. We have obtained nominal 2000 [Angstrom] period (1000 [Angstrom] bars with 1000 [Angstrom] slits) free standing, gold transmission gratings and measured their UV and atomic transmission characteristics. The geometric factor of a LENA imager based on this technology is comparable to that of other proposed LENA imagers. In addition, this of imager does not distort the neutral trajectories, allowing for high angular resolution.

Scime, E.E.; Funsten, H.O.; McComas, D.J.; Moore, K.R. (Los Alamos National Lab., NM (United States)); Gruntman, M. (University of Southern California, Los Angeles, CA (United States). Space Sciences Center)

1993-01-01

152

Advances in Reverberation Mapping of Quasars: Techniques, Experiments, and Implications  

NASA Astrophysics Data System (ADS)

Reverberation mapping is the only method capable of directly measuring the mass of supermassive black holes in galaxies outside the local universe. In addition, it has the potential to act as a cosmological distance probe to sources spanning 0 < z &;lt; 4. This method is applicable to broad line active galaxies, or quasars, by taking advantage of the light travel time delay between variability signals observed from the central black hole accretion disk continuum emission and from the photoionized line-emitting gas in the vicinity of the central source. This shifts the observational requirements from spatial dependence to temporal dependence in order to resolve the central structure. So far, reverberation mapping experiments have primarily been carried out locally (z < 0.3), but I will discuss how several new experiments are targeting more distant sources and/or using more time efficient methods to apply this technique to quasars with a broader range of observed spectral characteristics and across cosmological scales. I will also discuss how the resulting measurements have the potential to impact our understanding of cosmology and dark energy.

Denney, Kelly

2014-01-01

153

Molecular techniques and genetic alterations in head and neck cancer  

PubMed Central

It is well known that cellular DNA alterations can lead to the formation of cancer, and there has been much discovery in the pathways involved in the development of head and neck squamous cell carcinoma (HNSCC). With novel genome-wide molecular assays, our ability to detect these abnormalities has increased. We now have a better understanding of the molecular complexity of HNSCC, but there is still much research to be done. In this review, we discuss the well described genetic alterations and touch on the newer findings, as well as some of the future directions of head and neck cancer research. PMID:18674960

Ha, Patrick K; Chang, Steven S; Glazer, Chad A; Califano, Joseph A; Sidransky, David

2009-01-01

154

Clinical management of advanced gastric cancer: The role of new molecular drugs  

PubMed Central

Gastric cancer is the fourth most common malignant neoplasm and the second leading cause of death for cancer in Western countries with more than 20000 new cases yearly diagnosed in the United States. Surgery represents the main approach for this disease but, notwithstanding the advances in surgical techniques, we observed a minimal improvement in terms of overall survival with a significant increasing of relapsing disease rates. Despite the development of new drugs has significantly improved the effectiveness of chemotherapy, the prognosis of patients with unresectable or metastatic gastric adenocarcinoma remains poor. Recently, several molecular target agents have been investigated; in particular, trastuzumab represents the first target molecule showing improvements in overall survival in human epithelial growth factor 2-positive gastric cancer patients. New molecules targeting vascular epithelial growth factor, mammalian target of rapamycin, and anti hepatocyte growth factor-c-Met pathway are also under investigation, with interesting results. Anyway, it seems necessary to select more accurately the population to treat with new agents by the identification of new biomarkers in order to optimize the results. In this paper we review the actual “scenario” of targeted treatments, also focusing on the new agents in development for gastric cancer and gastro-esophageal carcinoma, discussing their efficacy and potential applications in clinical practice. PMID:25356019

De Vita, Ferdinando; Di Martino, Natale; Fabozzi, Alessio; Laterza, Maria Maddalena; Ventriglia, Jole; Savastano, Beatrice; Petrillo, Angelica; Gambardella, Valentina; Sforza, Vincenzo; Marano, Luigi; Auricchio, Annamaria; Galizia, Gennaro; Ciardiello, Fortunato; Orditura, Michele

2014-01-01

155

Parallel reactive molecular dynamics: Numerical methods and algorithmic techniques  

Microsoft Academic Search

Molecular dynamics modeling has provided a powerful tool for simulating and understanding diverse systems – ranging from materials processes to biophysical phenomena. Parallel formulations of these methods have been shown to be among the most scalable scientific computing applications. Many instances of this class of methods rely on a static bond structure for molecules, rendering them infeasible for reactive systems.

Hasan Metin Aktulga; Joseph C. Fogarty; Sagar A. Pandit; Ananth Y Grama

2009-01-01

156

Advances in Carcinogenic Metal Toxicity and Potential Molecular Markers  

PubMed Central

Metal compounds such as arsenic, cadmium, chromium, cobalt, lead, mercury, and nickel are classified as carcinogens affecting human health through occupational and environmental exposure. However, the underlying mechanisms involved in tumor formation are not well clarified. Interference of metal homeostasis may result in oxidative stress which represents an imbalance between production of free radicals and the system’s ability to readily detoxify reactive intermediates. This event consequently causes DNA damage, lipid peroxidation, protein modification, and possibly symptomatic effects for various diseases including cancer. This review discusses predominant modes of action and numerous molecular markers. Attention is paid to metal-induced generation of free radicals, the phenomenon of oxidative stress, damage to DNA, lipid, and proteins, responsive signal transduction pathways with major roles in cell growth and development, and roles of antioxidant enzymatic and DNA repair systems. Interaction of non-enzymatic antioxidants (carotenoids, flavonoids, glutathione, selenium, vitamin C, vitamin E, and others) with cellular oxidative stress markers (catalase, glutathione peroxidase, and superoxide dismutase) as well as certain regulatory factors, including AP-1, NF-?B, Ref-1, and p53 is also reviewed. Dysregulation of protective pathways, including cellular antioxidant network against free radicals as well as DNA repair deficiency is related to oncogenic stimulation. These observations provide evidence that emerging oxidative stress-responsive regulatory factors and DNA repair proteins are putative predictive factors for tumor initiation and progression. PMID:22272150

Koedrith, Preeyaporn; Seo, Young Rok

2011-01-01

157

Advanced Molecular Probes for Sequence-Specific DNA Recognition  

NASA Astrophysics Data System (ADS)

DNA detection can be achieved using the Watson-Crick base pairing with oligonucleotides or oligonucleotide analogs, followed by generation of a physical or chemical signal coupled with a transducer device. The nature of the probe is an essential feature which determines the performances of the sensing device. Many synthetic processes are presently available for "molecular engineering" of DNA probes, enabling label-free and PCR-free detection to be performed. Furthermore, many DNA analogs with improved performances are available and are under development; locked nucleic acids (LNA), peptide nucleic acids (PNA) and their analogs, morpholino oligonucleotides (MO) and other modified probes have shown improved properties of affinity and selectivity in target recognition compared to those of simple DNA probes. The performances of these probes in sensing devices, and the requirements for detection of unamplified DNA will be discussed in this chapter. Chemistry and architectures for conjugation of probes to reporter units, surfaces and nanostructures will also be discussed. Examples of probes used in ultrasensitive detection of unamplified DNA are listed.

Bertucci, Alessandro; Manicardi, Alex; Corradini, Roberto

158

Analysis of leading edge and trailing edge cover glass samples before and after treatment with advanced satellite contamination removal techniques  

NASA Technical Reports Server (NTRS)

Two samples from Long Duration Exposure Facility (LDEF) experiment M0003-4 were analyzed for molecular and particulate contamination prior to and following treatment with advanced satellite contamination removal techniques (CO2 gas/solid jet spray and oxygen ion beam). The pre- and post-cleaning measurements and analyses are presented. The jet spray removed particulates in seconds. The low energy reactive oxygen ion beam removed 5,000 A of photo polymerized organic hydrocarbon contamination in less than 1 hour. Spectroscopic analytical techniques were applied to the analysis of cleaning efficiency including: Fourier transform infrared, Auger, x ray photoemissions, energy dispersive x ray, and ultraviolet/visible. The results of this work suggest that the contamination studied here was due to spacecraft self-contamination enhanced by atomic oxygen plasma dynamics and solar UV radiation. These results also suggest the efficacy for the jet spray and ion beam contamination control technologies for spacecraft optical surfaces.

Hotaling, S. P.

1993-01-01

159

H Foundation Pilot Project Awards Center for Advanced Molecular Imaging (CAMI)  

E-print Network

, and T2*) · Whole body bioluminescence and fluorescence imaging (IVIS Spectrum, non-barrier facility) · Surgery suite · Cell culture room #12;· Image analysis Please see the CAMIH Foundation Pilot Project Awards Center for Advanced Molecular Imaging (CAMI

160

Chemistry 685 (CHE 685) Advanced Organic Chemistry: Organic Reaction Mechanisms and Molecular Interactions  

E-print Network

Chemistry 685 (CHE 685) Advanced Organic Chemistry: Organic Reaction Mechanisms and Molecular and physical chemistry Course description and rationale CHE685 is a graduate-level organic chemistry course. These two courses focus on physical organic chemistry, which deals with the structure and reactivity

Mather, Patrick T.

161

Recent advances in the molecular and genetic understanding of congenital gastrointestinal malformations.  

PubMed

Major developmental paradigms are highly conserved among vertebrates. The contribution of developmental biology to the understanding of human disease and regeneration has soared recently. We review advances in the molecular and genetic understanding of gastrointestinal development using evidence from both mammalian and nonmammalian models. When appropriate, we highlight relevance and applicability to human disease. PMID:23539045

Dauvé, Véronique; McLin, Valérie A

2013-07-01

162

Hairy cell leukemia: Update on molecular profiling and therapeutic advances.  

PubMed

Hairy cell leukemia was initially described as a clinicopathologic entity more than 50 years ago. We have subsequently discovered that HCL is really at least two diseases: classical HCL and the hairy cell leukemia variant. The former is among a small group of cancers exceptional for being (nearly) unified by a single genetic lesion, the BRAF V600E mutation. Over the past three decades, tremendous progress in both diagnostic and prognostic clarification has been accompanied by therapeutic advances in classical HCL. Consequently, this once uniformly fatal disease has been converted in most cases into a chronic illness enabling patients to live long and productive lives. In response to standard therapy, patients have high complete remission rates. Unfortunately, the long-term survival curves have not plateaued, revealing that this disease is controlled but not cured. Though rare and representing only about 10% of an already rare disease, those patients with the variant fare exceptionally poorly with standard therapy: complete response rates to purine nucleoside analogs are reported to be less than 50%, whereas the complete response rates in classical HCL are up to 90%. Novel small molecules targeting BRAF and the B-cell receptor signaling complex, and biologic agents like antibodies and immunotoxin conjugates are being explored for those patients who have relapsed. Substantial opportunities for continued research remain. This complex and multi-faceted disease incorporates challenges from altered immunity associated with the underlying disease and its treatments. Considering the rarity of this malignancy, optimization of patient management requires multi-institutional collaboration. The Hairy Cell Leukemia Foundation (www.hairycellleukemia.org) was formed to coordinate these efforts. PMID:25110197

Grever, Michael R; Blachly, James S; Andritsos, Leslie A

2014-09-01

163

Pushing CT and MR Imaging to the Molecular Level for Studying the "Omics": Current Challenges and Advancements  

PubMed Central

During the past decade, medical imaging has made the transition from anatomical imaging to functional and even molecular imaging. Such transition provides a great opportunity to begin the integration of imaging data and various levels of biological data. In particular, the integration of imaging data and multiomics data such as genomics, metabolomics, proteomics, and pharmacogenomics may open new avenues for predictive, preventive, and personalized medicine. However, to promote imaging-omics integration, the practical challenge of imaging techniques should be addressed. In this paper, we describe key challenges in two imaging techniques: computed tomography (CT) and magnetic resonance imaging (MRI) and then review existing technological advancements. Despite the fact that CT and MRI have different principles of image formation, both imaging techniques can provide high-resolution anatomical images while playing a more and more important role in providing molecular information. Such imaging techniques that enable single modality to image both the detailed anatomy and function of tissues and organs of the body will be beneficial in the imaging-omics field. PMID:24738056

Huang, Hsuan-Ming; Shih, Yi-Yu

2014-01-01

164

Molecular imaging with optics: primer and case for near-infrared fluorescence techniques in personalized medicine  

PubMed Central

We compare and contrast the development of optical molecular imaging techniques with nuclear medicine with a didactic emphasis for initiating readers into the field of molecular imaging. The nuclear imaging techniques of gamma scintigraphy, single-photon emission computed tomography, and positron emission tomography are first briefly reviewed. The molecular optical imaging techniques of bioluminescence and fluorescence using gene reporter/probes and gene reporters are described prior to introducing the governing factors of autofluorescence and excitation light leakage. The use of dual-labeled, near-infrared excitable and radio-labeled agents are described with comparative measurements between planar fluorescence and nuclear molecular imaging. The concept of time-independent and -dependent measurements is described with emphasis on integrating time-dependent measurements made in the frequency domain for 3-D tomography. Finally, we comment on the challenges and progress for translating near-infrared (NIR) molecular imaging agents for personalized medicine. PMID:19021311

Sevick-Muraca, Eva M.; Rasmussen, John C.

2010-01-01

165

Imaging Techniques Reveal that HIV Infects Host Cells Using a Molecular Entry Claw  

Cancer.gov

An advanced imaging technique known as electron tomography has allowed researchers to visualize an "entry claw," a unique structure formed between the human immunodeficiency virus (HIV) that causes AIDS and the cell it infects.

166

Advanced combustion techniques for controlling NO sub x emissions of high altitude cruise aircraft  

NASA Technical Reports Server (NTRS)

An array of experiments designed to explore the potential of advanced combustion techniques for controlling the emissions of aircraft into the upper atmosphere was discussed. Of particular concern are the oxides of nitrogen (NOx) emissions into the stratosphere. The experiments utilize a wide variety of approaches varying from advanced combustor concepts to fundamental flame tube experiments. Results are presented which indicate that substantial reductions in cruise NOx emissions should be achievable in future aircraft engines. A major NASA program is described which focuses the many fundamental experiments into a planned evolution and demonstration of the prevaporized-premixed combustion technique in a full-scale engine.

Rudey, R. A.; Reck, G. M.

1976-01-01

167

POC-Scale Testing of an Advanced Fine Coal Dewatering Equipment/Technique  

SciTech Connect

Froth flotation technique is an effective and efficient process for recovering of ultra-fine (minus 74 mm) clean coal. Economical dewatering of an ultra-fine clean coal product to a 20% level moisture will be an important step in successful implementation of the advanced cleaning processes. This project is a step in the Department of Energy's program to show that ultra-clean coal could be effectively dewatered to 20% or lower moisture using either conventional or advanced dewatering techniques. The cost-sharing contract effort is for 45 months beginning September 30, 1994. This report discusses technical progress made during the quarter from January 1 ? March 31, 1998.

B. K. Karekh; D. Tao; J. G. Groppo

1998-08-28

168

Using "Pseudomonas Putida xylE" Gene to Teach Molecular Cloning Techniques for Undergraduates  

ERIC Educational Resources Information Center

We have developed and implemented a serial experiment in molecular cloning laboratory course for undergraduate students majored in biotechnology. "Pseudomonas putida xylE" gene, encoding catechol 2, 3-dioxygenase, was manipulated to learn molecular biology techniques. The integration of cloning, expression, and enzyme assay gave students a chance…

Dong, Xu; Xin, Yi; Ye, Li; Ma, Yufang

2009-01-01

169

Optimization techniques in molecular structure and function elucidation  

PubMed Central

This paper discusses recent optimization approaches to the protein side-chain prediction problem, protein structural alignment, and molecular structure determination from X-ray diffraction measurements. The machinery employed to solve these problems has included algorithms from linear programming, dynamic programming, combinatorial optimization, and mixed-integer nonlinear programming. Many of these problems are purely continuous in nature. Yet, to this date, they have been approached mostly via combinatorial optimization algorithms that are applied to discrete approximations. The main purpose of the paper is to offer an introduction and motivate further systems approaches to these problems. PMID:20160866

Sahinidis, Nikolaos V.

2009-01-01

170

A Simple Karl Fischer Titration Technique for Measuring the Silanol Content of High Molecular Weight Polysiloxanes  

Microsoft Academic Search

This article presents a simple technique for measuring the silanol (SiOH) content of polysiloxanes having molecular weights of 26,000 amu or more. It extends an earlier procedure, in which 50°C methanol converts each silanol group into a methoxy group (SiOCH3) and the resulting water is measured by Karl Fischer titration. Unlike previous work, however, the present technique dissolves the high molecular

Louis A. Bloomfield

2012-01-01

171

Biochemistry and Molecular Biology Techniques for Person Characterization  

ERIC Educational Resources Information Center

Using the traditional serological tests and the most novel techniques for DNA fingerprinting, forensic scientists scan different traits that vary from person to person and use the data to include or exclude suspects based on matching with the evidence obtained in a criminal case. Although the forensic application of these methods is well known,…

Herrero, Salvador; Ivorra, Jose Luis; Garcia-Sogo, Magdalena; Martinez-Cortina, Carmen

2008-01-01

172

Chronic phase advance alters circadian physiological rhythms and peripheral molecular clocks  

PubMed Central

Shifting the onset of light, acutely or chronically, can profoundly affect responses to infection, tumor progression, development of metabolic disease, and mortality in mammals. To date, the majority of phase-shifting studies have focused on acute exposure to a shift in the timing of the light cycle, whereas the consequences of chronic phase shifts alone on molecular rhythms in peripheral tissues such as skeletal muscle have not been studied. In this study, we tested the effect of chronic phase advance on the molecular clock mechanism in two phenotypically different skeletal muscles. The phase advance protocol (CPA) involved 6-h phase advances (earlier light onset) every 4 days for 8 wk. Analysis of the molecular clock, via bioluminescence recording, in the soleus and flexor digitorum brevis (FDB) muscles and lung demonstrated that CPA advanced the phase of the rhythm when studied immediately after CPA. However, if the mice were placed into free-running conditions (DD) for 2 wk after CPA, the molecular clock was not phase shifted in the two muscles but was still shifted in the lung. Wheel running behavior remained rhythmic in CPA mice; however, the endogenous period length of the free-running rhythm was significantly shorter than that of control mice. Core body temperature, cage activity, and heart rate remained rhythmic throughout the experiment, although the onset of the rhythms was significantly delayed with CPA. These results provide clues that lifestyles associated with chronic environmental desynchrony, such as shift work, can have disruptive effects on the molecular clock mechanism in peripheral tissues, including both types of skeletal muscle. Whether this can contribute, long term, to increased incidence of insulin resistance/metabolic disease requires further study. PMID:23703115

Wolff, Gretchen; Duncan, Marilyn J.

2013-01-01

173

Reflection mass spectrometry technique for monitoring and controlling composition during molecular beam epitaxy  

SciTech Connect

This invention is comprised of a method for on-line accurate monitoring and precise control of molecular beam epitaxial growth of Groups III-III-V or Groups III-V-V layers in an advanced semiconductor device incorporates reflection mass spectrometry. The reflection mass spectrometry is responsive to intentional perturbations in molecular fluxes incident on a substrate by accurately measuring the molecular fluxes reflected from the substrate. The reflected flux is extremely sensitive to the state of the growing surface and the measurements obtained enable control of newly forming surfaces that are dynamically changing as a result of growth.

Brennan, T.M.; Hammons, B.E.; Tsao, J.Y.

1990-08-15

174

Reflection mass spectrometry technique for monitoring and controlling composition during molecular beam epitaxy  

DOEpatents

A method for on-line accurate monitoring and precise control of molecular beam epitaxial growth of Groups III-III-V or Groups III-V-V layers in an advanced semiconductor device incorporates reflection mass spectrometry. The reflection mass spectrometry is responsive to intentional perturbations in molecular fluxes incident on a substrate by accurately measuring the molecular fluxes reflected from the substrate. The reflected flux is extremely sensitive to the state of the growing surface and the measurements obtained enable control of newly forming surfaces that are dynamically changing as a result of growth.

Brennan, Thomas M. (Albuquerque, NM); Hammons, B. Eugene (Tijeras, NM); Tsao, Jeffrey Y. (Albuquerque, NM)

1992-01-01

175

Modulation/demodulation techniques for satellite communications. Part 2: Advanced techniques. The linear channel  

NASA Technical Reports Server (NTRS)

A theory is presented for deducing and predicting the performance of transmitter/receivers for bandwidth efficient modulations suitable for use on the linear satellite channel. The underlying principle used is the development of receiver structures based on the maximum-likelihood decision rule. The application of the performance prediction tools, e.g., channel cutoff rate and bit error probability transfer function bounds to these modulation/demodulation techniques.

Omura, J. K.; Simon, M. K.

1982-01-01

176

Application of Advanced Magnetic Resonance Imaging Techniques in Evaluation of the Lower Extremity  

PubMed Central

Synopsis This article reviews current magnetic resonance imaging techniques for imaging the lower extremity, focusing on imaging of the knee, ankle, and hip joints. Recent advancements in MRI include imaging at 7 Tesla, using multiple receiver channels, T2* imaging, and metal suppression techniques, allowing more detailed visualization of complex anatomy, evaluation of morphological changes within articular cartilage, and imaging around orthopedic hardware. PMID:23622097

Braun, Hillary J.; Dragoo, Jason L.; Hargreaves, Brian A.; Levenston, Marc E.; Gold, Garry E.

2012-01-01

177

Polymicrobial chronic endophthalmitis diagnosed by culture and molecular technique.  

PubMed

Accurate etiological diagnosis is the key to prevention of ocular morbidity in endophthalmitis cases. A 66 year old male was suffering from chronic endophthalmitis post-cataract surgery. Polymerase chain reaction examination on anterior chamber fluid was positive for Propionibacterium acnes but negative for the panfungal genome. He was advised vitrectomy with intravitreal injections. Polymerase chain reaction of vitreous aspirate was positive for P.acnes as well as panfungal genome. The vitreous sample also grew yeast in culture which was identified as Candida pseudotropicalis. Patient was treated on an alternate day regimen of intravitreal Vancomycin and Amphotericin B in the post-operative period. There was improvement in vision at final follow up. Chronic endophthalmitis can have polymicrobial etiology which will require appropriate diagnostic and therapeutic strategies. The role of molecular testing is vital in these cases as growth in culture is often negative. PMID:25008833

Mukherjee, A; Pramanik, S; Das, D; Roy, R; Therese, K L

2014-01-01

178

Advances in the Use of Molecular Markers for Source Apportionment of Atmospheric Organic Aerosols  

NASA Astrophysics Data System (ADS)

Over the past decade, there has been significant effort directed at measuring particle-phase organic compounds in air pollution emission sources and in the atmosphere. A subset of these organic compounds are relatively unique to the emissions from specific air pollution source categories and are believed to be stable enough in the atmosphere to be used as source tracers. To date, studies have been conducted in North America, Asia and Europe in both remote and urbanized locations that have used these organic compound tracers, also called molecular markers, for source attribution studies. The major short-comings of these studies are the uncertainties associated with developing site and season specific molecular marker source profiles and the absence of source fingerprints for secondary organic aerosol. Recent advances in molecular marker chemical analysis methods has lead to two key advances for molecular marker source apportionment efforts: 1) sufficiently large data sets of molecular marker measures have been generated that now allow multivariate receptor models to be used in parallel with chemical mass balance (CMB) models, and 2) compounds that are believed to be predominately associated with secondary organic aerosol (SOA) have been identified and can be routinely analyzed in organic aerosol samples. Given these advances, data sets have been generated that can be used to apportion atmospheric organic aerosols to both primary and secondary organic aerosols without the use of source profiles. Background on molecular markers will be presented along with recent organic aerosol source apportionment results that were obtained using multivariate receptor models to analyze molecular marker data sets obtained in the Midwestern United States. These data sets include a daily time series of molecular marker concentration data from the Midwest Supersite in East St. Louis that spans two years and a monthly average tracer data for a year that were simultaneously obtained in St. Louis, Chicago, Detroit, Indianapolis, Cincinnati, and Bondville. The results of these studies will be presented along with a comparison of the molecular marker source profiles derived from a multivariate receptor models and source testing activities. Such analyses provide insight into the atmospheric stability of these molecular markers and their uniqueness to source categories.

Schauer, J. J.; Sheesley, R. J.; Jaeckels, J. M.

2006-12-01

179

Advanced diagnostics applied to fish liver tumours: relating pathology to underlying molecular aetiology.  

PubMed

Liver tumours in flatfish have been diagnosed using histopathology for decades in order to monitor the impacts of marine pollution in coastal and estuarine environments. This traditional method has been coupled with molecular analyses of tumours in the liver of the dab, Limanda limanda, in order to elucidate underpinning molecular level aetiology of such disease. A laser capture microdissection technique for molecular investigation of cancer has been applied in fish. The present study provides optimized steps for environmental sample utilisation: a procedure for field sample collection and handling; a method allowing reliable identification of lesions on frozen tissue sections; and, downstream molecular analyses of tumourigenesis markers (retinoblastoma gene) in laser microdissected samples. This approach facilitates the use of wild flatfish as a model of environmentally-induced tumourigenesis, and has wide applicability to any disease pathology for which the underpinning molecular aetiology is required. PMID:23683584

Lerebours, Adélaïde; Bignell, John P; Stentiford, Grant D; Feist, Stephen W; Lyons, Brett P; Rotchell, Jeanette M

2013-07-15

180

Fabrication of advanced electrochemical energy materials using sol-gel processing techniques  

NASA Technical Reports Server (NTRS)

Advanced materials play an important role in electrochemical energy devices such as batteries, fuel cells, and electrochemical capacitors. They are being used as both electrodes and electrolytes. Sol-gel processing is a versatile solution technique used in fabrication of ceramic materials with tailored stoichiometry, microstructure, and properties. The application of sol-gel processing in the fabrication of advanced electrochemical energy materials will be presented. The potentials of sol-gel derived materials for electrochemical energy applications will be discussed along with some examples of successful applications. Sol-gel derived metal oxide electrode materials such as V2O5 cathodes have been demonstrated in solid-slate thin film batteries; solid electrolytes materials such as beta-alumina for advanced secondary batteries had been prepared by the sol-gel technique long time ago; and high surface area transition metal compounds for capacitive energy storage applications can also be synthesized with this method.

Chu, C. T.; Chu, Jay; Zheng, Haixing

1995-01-01

181

Modulation/demodulation techniques for satellite communications. Part 3: Advanced techniques. The nonlinear channel  

NASA Technical Reports Server (NTRS)

A theory for deducing and predicting the performance of transmitter/receivers for bandwidth efficient modulations suitable for use on the nonlinear satellite channel is presented. The underlying principle used throughout is the development of receiver structures based on the maximum likelihood decision rule and aproximations to it. The bit error probability transfer function bounds developed in great detail in Part 4 is applied to these modulation/demodulation techniques. The effects of the various degrees of receiver mismatch are considered both theoretically and by numerous illustrative examples.

Omura, J. K.; Simon, M. K.

1982-01-01

182

Advanced superconducting gradiometer\\/Magnetometer arrays and a novel signal processing technique  

Microsoft Academic Search

Recent developments in superconducting magnetic gradiometer technology have led to the construction of advanced ultrasensitive gradiometer\\/magnetometer arrays. Details of construction techniques and data showing operational capabilities are presented. The most recent of the gradiometer\\/magnetometer arrays simultaneously measures five independent spatial gradients of the magnetic field and three vector components of the magnetic field. The measured signals from this array are

W. Wynn; C. Frahm; P. Carroll; R. Clark; J. Wellhoner; M. Wynn

1975-01-01

183

Coolant void reactivity adjustments in advanced CANDU lattices using adjoint sensitivity technique  

Microsoft Academic Search

Coolant void reactivity (CVR) is an important factor in reactor accident analysis. Here we study the adjustments of CVR at beginning of burnup cycle (BOC) and keff at end of burnup cycle (EOC) for a 2D Advanced CANDU Reactor (ACR) lattice using the optimization and adjoint sensitivity techniques. The sensitivity coefficients are evaluated using the perturbation theory based on the

M. Assawaroongruengchot; G. Marleau

2008-01-01

184

Advanced Diffusion-Weighted Magnetic Resonance Imaging Techniques of the Human Spinal Cord  

PubMed Central

Unlike those of the brain, advances in diffusion-weighted imaging (DWI) of the human spinal cord have been challenged by the more complicated and inhomogeneous anatomy of the spine, the differences in magnetic susceptibility between adjacent air and fluid-filled structures and the surrounding soft tissues, and the inherent limitations of the initially used echo-planar imaging techniques used to image the spine. Interval advances in DWI techniques for imaging the human spinal cord, with the specific aims of improving the diagnostic quality of the images, and the simultaneous reduction in unwanted artifacts have resulted in higher-quality images that are now able to more accurately portray the complicated underlying anatomy and depict pathologic abnormality with improved sensitivity and specificity. Diffusion tensor imaging (DTI) has benefited from the advances in DWI techniques, as DWI images form the foundation for all tractography and DTI. This review provides a synopsis of the many recent advances in DWI of the human spinal cord, as well as some of the more common clinical uses for these techniques, including DTI and tractography. PMID:22158130

Andre, Jalal B.; Bammer, Roland

2012-01-01

185

Real-time application of advanced three-dimensional graphic techniques for research aircraft simulation  

NASA Technical Reports Server (NTRS)

Visual aids are valuable assets to engineers for design, demonstration, and evaluation. Discussed here are a variety of advanced three-dimensional graphic techniques used to enhance the displays of test aircraft dynamics. The new software's capabilities are examined and possible future uses are considered.

Davis, Steven B.

1990-01-01

186

A User-Oriented Interface for Generalised Informetric Analysis Based on Applying Advanced Data Modelling Techniques.  

ERIC Educational Resources Information Center

Presents a user-oriented interface for generalized informetric analysis and demonstrates how informetric calculations can be specified through advanced data modeling techniques. Topics include bibliographic data; online information retrieval systems; citation networks; query interface; impact factors; data restructuring; and multi-level…

Jarvelin, Kalervo; Ingwersen, Peter; Niemi, Timo

2000-01-01

187

A review of present techniques and methodological advances in analyzing 234  

E-print Network

A review of present techniques and methodological advances in analyzing 234 Th in aquatic systems Abstract The short-lived thorium isotope 234 Th (half-life 24.1 days) has been used as a tracer particles has stimulated a rapidly increasing number of studies that require analyses of 234 Th in both

Buesseler, Ken

188

Advanced Signal Processing Techniques for Fault Detection and Diagnosis in a Wind Turbine  

E-print Network

Advanced Signal Processing Techniques for Fault Detection and Diagnosis in a Wind Turbine Induction rotor bars and bearing damages. Index Terms--Wind turbines, motor current signature analy- sis, time of maintenance in offshore environment, teledetection of wind turbine faults is becoming a crucial issue

Paris-Sud XI, Université de

189

The development of optical microscopy techniques for the advancement of single-particle studies  

NASA Astrophysics Data System (ADS)

Single particle orientation and rotational tracking (SPORT) has recently become a powerful optical microscopy tool that can expose many molecular motions. Unfortunately, there is not yet a single microscopy technique that can decipher all particle motions in all environmental conditions, thus there are limitations to current technologies. Within, the two powerful microscopy tools of total internal reflection and interferometry are advanced to determine the position, orientation, and optical properties of metallic nanoparticles in a variety of environments. Total internal reflection is an optical phenomenon that has been applied to microscopy to produce either fluorescent or scattered light. The non-invasive far-field imaging technique is coupled with a near-field illumination scheme that allows for better axial resolution than confocal microscopy and epi-fluorescence microscopy. By controlling the incident illumination angle using total internal reflection fluorescence (TIRF) microscopy, a new type of imaging probe called "non-blinking" quantum dots (NBQDs) were super-localized in the axial direction to sub-10-nm precision. These particles were also used to study the rotational motion of microtubules being propelled by the motor protein kinesin across the substrate surface. The same instrument was modified to function under total internal reflection scattering (TIRS) microscopy to study metallic anisotropic nanoparticles and their dynamic interactions with synthetic lipid bilayers. Utilizing two illumination lasers with opposite polarization directions at wavelengths corresponding to the short and long axis surface plasmon resonance (SPR) of the nanoparticles, both the in-plane and out-of-plane movements of many particles could be tracked simultaneously. When combined with Gaussian point spread function (PSF) fitting for particle super-localization, the binding status and rotational movement could be resolved without degeneracy. TIRS microscopy was also used to find the 3D orientation of stationary metallic anisotropic nanoparticles utilizing only long-axis SPR enhancement. The polarization direction of the illuminating light was rotated causing the relative intensity of p-polarized and s-polarized light within the evanescent field to change. The interaction of the evanescent field with the particles is dependent on the orientation of the particle producing an intensity curve. This curve and the in-plane angle can be compared with simulations to accurately determine the 3D orientation. Differential interference contrast (DIC) microscopy is another non-invasive far-field technique based upon interferometry that does not rely on staining or other contrast enhancing techniques. In addition, high numerical aperture condensers and objectives can be used to give a very narrow depth of field allowing for the optical tomography of samples, which makes it an ideal candidate to study biological systems. DIC microscopy has also proven itself in determining the orientation of gold nanorods in both engineered environments and within cells. Many types of nanoparticles and nanostructures have been synthesized using lithographic techniques on silicon wafer substrates. Traditionally, reflective mode DIC microscopes have been developed and applied to the topographical study of reflective substrates and the imaging of chips on silicon wafers. Herein, a laser-illuminated reflected-mode DIC was developed for studying nanoparticles on reflective surfaces.

Marchuk, Kyle

190

The development of optical microscopy techniques for the advancement of single-particle studies  

SciTech Connect

Single particle orientation and rotational tracking (SPORT) has recently become a powerful optical microscopy tool that can expose many molecular motions. Unfortunately, there is not yet a single microscopy technique that can decipher all particle motions in all environmental conditions, thus there are limitations to current technologies. Within, the two powerful microscopy tools of total internal reflection and interferometry are advanced to determine the position, orientation, and optical properties of metallic nanoparticles in a variety of environments. Total internal reflection is an optical phenomenon that has been applied to microscopy to produce either fluorescent or scattered light. The non-invasive far-field imaging technique is coupled with a near-field illumination scheme that allows for better axial resolution than confocal microscopy and epi-fluorescence microscopy. By controlling the incident illumination angle using total internal reflection fluorescence (TIRF) microscopy, a new type of imaging probe called “non-blinking” quantum dots (NBQDs) were super-localized in the axial direction to sub-10-nm precision. These particles were also used to study the rotational motion of microtubules being propelled by the motor protein kinesin across the substrate surface. The same instrument was modified to function under total internal reflection scattering (TIRS) microscopy to study metallic anisotropic nanoparticles and their dynamic interactions with synthetic lipid bilayers. Utilizing two illumination lasers with opposite polarization directions at wavelengths corresponding to the short and long axis surface plasmon resonance (SPR) of the nanoparticles, both the in-plane and out-of-plane movements of many particles could be tracked simultaneously. When combined with Gaussian point spread function (PSF) fitting for particle super-localization, the binding status and rotational movement could be resolved without degeneracy. TIRS microscopy was also used to find the 3D orientation of stationary metallic anisotropic nanoparticles utilizing only long-axis SPR enhancement. The polarization direction of the illuminating light was rotated causing the relative intensity of p-polarized and s-polarized light within the evanescent field to change. The interaction of the evanescent field with the particles is dependent on the orientation of the particle producing an intensity curve. This curve and the in-plane angle can be compared with simulations to accurately determine the 3D orientation. Differential interference contrast (DIC) microscopy is another non-invasive far-field technique based upon interferometry that does not rely on staining or other contrast enhancing techniques. In addition, high numerical aperture condensers and objectives can be used to give a very narrow depth of field allowing for the optical tomography of samples, which makes it an ideal candidate to study biological systems. DIC microscopy has also proven itself in determining the orientation of gold nanorods in both engineered environments and within cells. Many types of nanoparticles and nanostructures have been synthesized using lithographic techniques on silicon wafer substrates. Traditionally, reflective mode DIC microscopes have been developed and applied to the topographical study of reflective substrates and the imaging of chips on silicon wafers. Herein, a laser-illuminated reflected-mode DIC was developed for studying nanoparticles on reflective surfaces.

Marchuk, Kyle

2013-05-15

191

A spatial correlation technique for estimating velocity fields using molecular tagging velocimetry (MTV)  

NASA Astrophysics Data System (ADS)

A direct spatial image correlation technique is presented for estimating the Lagrangian displacement vector from image pairs based on molecular tagging diagnostics. The procedure provides significant improvement in measurement accuracy compared to existing approaches for molecular tagging velocimetry (MTV) analysis. Furthermore, this technique is of more general utility in that it is able to accommodate other laser tagging patterns besides the usual grid arrangement. Simulations are performed to determine the effects of many experimental and processing issues on the sub-pixel accuracy of displacement estimates. The results provide guidelines for optimizing the implementation of MTV. Experimental data in support of this processing technique are provided.

Gendrich, C. P.; Koochesfahani, M. M.

1996-11-01

192

The Impact of Advances in Molecular Genetic Pathology on the Classification, Diagnosis and Treatment of Selected Soft Tissue Tumors of the Head and Neck  

PubMed Central

Recent advances in molecular pathology have had a significant impact on the diagnosis, classification, and treatment of soft tissue tumors. The practical application of these discoveries promises to assist greatly in the evaluation and treatment of soft tissue neoplasms in the head and neck region—an area characterized by exceedingly complex anatomy that often restricts the ample sampling of lesions and complete surgical resection. This reviews details some ways in which molecular techniques have strengthened conventional diagnostic and management approaches to low-grade fibromyxoid sarcoma, angiomatoid (malignant) fibrous histiocytoma, and dermatofibrosarcoma protuberans, all of which may involve the head and neck region. PMID:20237992

Garcia, Joaquin J.

2010-01-01

193

Achieving molecular selectivity in imaging using multiphoton Raman spectroscopy techniques  

SciTech Connect

In the case of most imaging methods, contrast is generated either by physical properties of the sample (Differential Image Contrast, Phase Contrast), or by fluorescent labels that are localized to a particular protein or organelle. Standard Raman and infrared methods for obtaining images are based upon the intrinsic vibrational properties of molecules, and thus obviate the need for attached flurophores. Unfortunately, they have significant limitations for live-cell imaging. However, an active Raman method, called Coherent Anti-Stokes Raman Scattering (CARS), is well suited for microscopy, and provides a new means for imaging specific molecules. Vibrational imaging techniques, such as CARS, avoid problems associated with photobleaching and photo-induced toxicity often associated with the use of fluorescent labels with live cells. Because the laser configuration needed to implement CARS technology is similar to that used in other multiphoton microscopy methods, such as two -photon fluorescence and harmonic generation, it is possible to combine imaging modalities, thus generating simultaneous CARS and fluorescence images. A particularly powerful aspect of CARS microscopy is its ability to selectively image deuterated compounds, thus allowing the visualization of molecules, such as lipids, that are chemically indistinguishable from the native species.

Holtom, Gary R. (BATTELLE (PACIFIC NW LAB)); Thrall, Brian D. (BATTELLE (PACIFIC NW LAB)); Chin, Beek Yoke (BATTELLE (PACIFIC NW LAB)); Wiley, H Steven (BATTELLE (PACIFIC NW LAB)); Colson, Steven D. (BATTELLE (PACIFIC NW LAB))

2000-12-01

194

Nondestructive Characterization by Advanced Synchrotron Light Techniques: Spectromicroscopy and Coherent Radiology  

PubMed Central

The advanced characteristics of synchrotron light has led in recent years to the development of a series of new experimental techniques to investigate chemical and physical properties on a microscopic scale. Although originally developed for materials science and biomedical research, such techniques find increasing applications in other domains – and could be quite useful for the study and conservation of cultural heritage. Specifically, they can nondestructively provide detailed chemical composition information that can be useful for the identification of specimens, for the discovery of historical links based on the sources of chemical raw materials and on chemical processes, for the analysis of damage, their causes and remedies and for many other issues. Likewise, morphological and structural information on a microscopic scale is useful for the identification, study and preservation of many different cultural and historical specimens. We concentrate here on two classes of techniques: in the first case, photoemission spectromicroscopy. This is the result of the advanced evolution of photoemission techniques like ESCA (Electron Microscopy for Chemical Analysis). By combining high lateral resolution to spectroscopy, photoemission spectromicroscopy can deliver fine chemical information on a microscopic scale in a nondestructive fashion. The second class of techniques exploits the high lateral coherence of modern synchrotron sources, a byproduct of the quest for high brightness or brilliance. We will see that such techniques now push radiology into the submicron scale and the submillisecond time domain. Furthermore, they can be implemented in a tomographic mode, increasing the information and becoming potentially quite useful for the analysis of cultural heritage specimens.

Margaritondo, Giorgio; Hwu, Yeukuang; Je, Jung Ho

2008-01-01

195

Recent advances in small molecular, non-polymeric organic hole transporting materials for solid-state DSSC  

NASA Astrophysics Data System (ADS)

Issue from thin-film technologies, dye-sensitized solar cells have become one of the most promising technologies in the field of renewable energies. Their success is not only due to their low weight, the possibility of making large flexible surfaces, but also to their photovoltaic efficiency which are found to be more and more significant (>12% with a liquid electrolyte, >7% with a solid organic hole conductor). This short review highlights recent advances in the characteristics and use of low-molecular-weight glass-forming organic materials as hole transporters in all solid-state dye-sensitized solar cells. These materials must feature specific physical and chemical properties that will ensure both the operation of a photovoltaic cell and the easy implementation. This review is an english extended version based on our recent article published in Matériaux & Techniques 101, 102 (2013).

Bui, Thanh-Tuan; Goubard, Fabrice

2013-10-01

196

Advanced semiconductor diagnosis by multidimensional electron-beam-induced current technique.  

PubMed

We present advanced semiconductor diagnosis by using electron-beam-induced current (EBIC) technique. By varying the parameters such as temperature, accelerating voltage (V(acc)), bias voltage, and stressing time, it is possible to extend EBIC application from conventional defect characterization to advanced device diagnosis. As an electron beam can excite a certain volume even beneath the surface passive layer, EBIC can be effectively employed to diagnose complicated devices with hybrid structure. Three topics were selected to demonstrate EBIC applications. First, the recombination activities of grain boundaries and their interaction with Fe impurity in photovoltaic multicrystalline Si (mc-Si) are clarified by temperature-dependent EBIC. Second, the detection of dislocations between strained-Si and SiGe virtual substrate are shown to overcome the limitation of depletion region. Third, the observation of leakage sites in high-k gate dielectric is demonstrated for the characterization of advanced hybrid device structures. PMID:18615457

Chen, J; Yuan, X; Sekiguchi, T

2008-01-01

197

POC-scale testing of an advanced fine coal dewatering equipment/technique  

SciTech Connect

Froth flotation technique is an effective and efficient process for recovering of ultra-fine (minus 74 pm) clean coal. Economical dewatering of an ultra-fine clean-coal product to a 20% level moisture will be an important step in successful implementation of the advanced cleaning processes. This project is a step in the Department of Energy`s program to show that ultra-clean coal could be effectively dewatered to 20% or lower moisture using either conventional or advanced dewatering techniques. The cost-sharing contract effort is for 36 months beginning September 30, 1994. This report discusses technical progress made during the quarter from July 1 - September 30, 1997.

NONE

1998-09-01

198

POC-Scale Testing of an Advanced Fine Coal Dewatering Equipment/Technique.  

SciTech Connect

Froth flotation technique is an effective and efficient process for recovering of ultra-fine (minus 74 mm) clean coal. Economical dewatering of an ultra-fine clean coal product to a 20% level moisture will be an important step in the successful implementation of the advanced cleaning processes. This project is a step in the Department of Energy`s program to show that ultra-clean coal could be effectively dewatered to 20% or lower moisture using either conventional or advanced dewatering techniques. The cost-sharing contract effort is for 36 months beginning September 30, 1994. This report discusses technical progress made during the quarter from April 1 - June 30, 1997.

Tao, D.; Groppo, J.G.; Parekh, B.K.

1997-12-31

199

POC-Scale Testing of an Advanced Fine Coal Dewatering Equipment/Technique.  

SciTech Connect

Froth flotation technique is an effective and efficient process for recovering of ultra-fine (minus 74 mm) clean coal. Economical dewatering of an ultra-fine clean-coal product to a 20% level moisture will be an important step in successful implementation of the advanced cleaning processes. This project is a step in the Department of Energy`s program to show that ultra-clean coal could be effectively dewatered to 20% or lower moisture using either conventional or advanced dewatering techniques. The cost-sharing contract effort is for 36 months beginning September 30, 1994. This report discusses technical progress made during the quarter from July 1 - September 30, 1997.

Tao, D.; Groppo, J.G.; Parekh, B.K.

1997-11-05

200

Unified Instrumentation: Examining the Simultaneous Application of Advanced Measurement Techniques for Increased Wind Tunnel Testing Capability  

NASA Technical Reports Server (NTRS)

A Unified Instrumentation Test examining the combined application of Pressure Sensitive Paint, Projection Moire Interferometry, Digital Particle Image Velocimetry, Doppler Global Velocimetry, and Acoustic Microphone Array has been conducted at the NASA Langley Research Center. The fundamental purposes of conducting the test were to: (a) identify and solve compatibility issues among the techniques that would inhibit their simultaneous application in a wind tunnel, and (b) demonstrate that simultaneous use of advanced instrumentation techniques is feasible for increasing tunnel efficiency and identifying control surface actuation / aerodynamic reaction phenomena. This paper provides summary descriptions of each measurement technique used during the Unified Instrumentation Test, their implementation for testing in a unified fashion, and example results identifying areas of instrument compatibility and incompatibility. Conclusions are drawn regarding the conditions under which the measurement techniques can be operated simultaneously on a non-interference basis. Finally, areas requiring improvement for successfully applying unified instrumentation in future wind tunnel tests are addressed.

Fleming, Gary A. (Editor); Bartram, Scott M.; Humphreys, William M., Jr.; Jenkins, Luther N.; Jordan, Jeffrey D.; Lee, Joseph W.; Leighty, Bradley D.; Meyers, James F.; South, Bruce W.; Cavone, Angelo A.; Ingram, JoAnne L.

2002-01-01

201

Advanced digital modulation: Communication techniques and monolithic GaAs technology  

NASA Technical Reports Server (NTRS)

Communications theory and practice are merged with state-of-the-art technology in IC fabrication, especially monolithic GaAs technology, to examine the general feasibility of a number of advanced technology digital transmission systems. Satellite-channel models with (1) superior throughput, perhaps 2 Gbps; (2) attractive weight and cost; and (3) high RF power and spectrum efficiency are discussed. Transmission techniques possessing reasonably simple architectures capable of monolithic fabrication at high speeds were surveyed. This included a review of amplitude/phase shift keying (APSK) techniques and the continuous-phase-modulation (CPM) methods, of which MSK represents the simplest case.

Wilson, S. G.; Oliver, J. D., Jr.; Kot, R. C.; Richards, C. R.

1983-01-01

202

Combined preputial advancement and phallopexy as a revision technique for treating paraphimosis in a dog.  

PubMed

A 7-year-old neutered male Jack Russell terrier-cross was presented for signs of recurrent paraphimosis, despite previous surgical enlargement of the preputial ostium. Revision surgery was performed using a combination of preputial advancement and phallopexy, which resulted in complete and permanent coverage of the glans penis by the prepuce, and at 1 year postoperatively, no recurrence of paraphimosis had been observed. The combined techniques allow preservation of the normal penile anatomy, are relatively simple to perform and provide a cosmetic result. We recommend this combination for the treatment of paraphimosis in the dog, particularly when other techniques have failed. PMID:25348145

Wasik, Sm; Wallace, Am

2014-11-01

203

Advances on the Masquelet technique using a cage and nail construct.  

PubMed

Traumatic, cancerous or infectious loss of bone is treated by either amputation or reconstruction. With limb salvage always preferable, surgeons rely on already established techniques such as grafting and distraction osteogenesis to avoid amputation, and ideally restore structure and thus function. The Masquelet technique is an effective method of bone reconstruction and limb salvage which is underreported in the English literature, and we report a case with advances using a cage and nail construct, resulting in successful eradication of methicillin resistant staphylococcus aureus infection and reconstitution of a 17 cm diaphyseal defect in the tibia. PMID:22072192

O'Malley, Natasha T; Kates, Stephen L

2012-02-01

204

Development of advanced electron holographic techniques and application to industrial materials and devices.  

PubMed

The development of a transmission electron microscope equipped with a field emission gun paved the way for electron holography to be put to practical use in various fields. In this paper, we review three advanced electron holography techniques: on-line real-time electron holography, three-dimensional (3D) tomographic holography and phase-shifting electron holography, which are becoming important techniques for materials science and device engineering. We also describe some applications of electron holography to the analysis of industrial materials and devices: GaAs compound semiconductors, solid oxide fuel cells and all-solid-state lithium ion batteries. PMID:23536696

Yamamoto, Kazuo; Hirayama, Tsukasa; Tanji, Takayoshi

2013-06-01

205

The investigation of advanced remote sensing techniques for the measurement of aerosol characteristics  

NASA Technical Reports Server (NTRS)

Advanced remote sensing techniques and inversion methods for the measurement of characteristics of aerosol and gaseous species in the atmosphere were investigated. Of particular interest were the physical and chemical properties of aerosols, such as their size distribution, number concentration, and complex refractive index, and the vertical distribution of these properties on a local as well as global scale. Remote sensing techniques for monitoring of tropospheric aerosols were developed as well as satellite monitoring of upper tropospheric and stratospheric aerosols. Computer programs were developed for solving multiple scattering and radiative transfer problems, as well as inversion/retrieval problems. A necessary aspect of these efforts was to develop models of aerosol properties.

Deepak, A.; Becher, J.

1979-01-01

206

The Double Edge Aerosol and Molecular Techniques for Doppler Lidar Wind Measurement  

NASA Technical Reports Server (NTRS)

We have developed the theory for aerosol- and molecular-based lidar measurements of the wind using double edge versions of the edge technique. Aerosol-based wind measurements have been made at Goddard Space Flight Center and molecular-based wind measurements at the University of Geneva. We have demonstrated atmospheric measurements using these techniques for altitudes from 1 to more than 10 km. Measurement accuracies of better than 1.25 m/s have been obtained with integration times from 5 to 30 seconds. The measurements can be scaled to space and agree, within a factor of two, with satellite-based simulations of performance based on Poisson statistics.

Korb, C. Laurence; Flesia, Cristina

1998-01-01

207

A major advance in characterizing nanoporous solids using a complementary triad of existing techniques.  

PubMed

A triad of complementary techniques, namely high-resolution gas adsorption coupled with hysteresis scanning and density functional theory, rotation electron diffraction, and electron tomography, has revealed the intracrystalline nature and connectivity of size-tailored mesopores in surfactant-templated mesostructured zeolite-Y with new clarity. This approach constitutes a significant advance in the elucidation of the structure of nanoporous solids. PMID:25262654

Thomas, John Meurig; Leary, Rowan K

2014-11-01

208

Recent Advances in Stable Isotope Techniques for N2O Source Partitioning in Soils  

Microsoft Academic Search

The use of 13C, 15N and 18O enables us to overcome uncertainties associated with soil C and N processes and to assess the links between species diversity and ecosystem function. Recent advances in stable isotope techniques enable determination of process rates, and are fundamental for examining interactions between C and N cycles. Here we will introduce the 15N-, 18O- and

E. Baggs; L. Mair; S. Mahmood

2007-01-01

209

A New Experimental Technique for the Multi-axial Testing of Advanced High Strength Steel Sheets  

Microsoft Academic Search

This paper deals with the development of a new experimental technique for the multi-axial testing of flat sheets and its application\\u000a to advanced high strength steels. In close analogy with the traditional tension-torsion test for bulk materials, the sheet\\u000a material is subject to combined tension and shear loading. Using a custom-made dual actuator hydraulic testing machine, combinations\\u000a of normal and

D. Mohr; M. Oswald

2008-01-01

210

Study of advanced techniques for determining the long term performance of components  

NASA Technical Reports Server (NTRS)

The application of existing and new technology to the problem of determining the long-term performance capability of liquid rocket propulsion feed systems is discussed. The long term performance of metal to metal valve seats in a liquid propellant fuel system is stressed. The approaches taken in conducting the analysis are: (1) advancing the technology of characterizing components through the development of new or more sensitive techniques and (2) improving the understanding of the physical of degradation.

1973-01-01

211

Advanced burden level measurement radars using FFT signal processing techniques. [Fast Fourier Transform  

Microsoft Academic Search

Advanced design level-measuring radars have been developed and installed at Bethlehem Steel's Burns Harbor Plant to measure burden height in operating blast furnaces. Modern signal processing techniques are used in conjunction with a self-calibrating wideband swept-frequency dual-antenna radar to enhance measurement accuracy and better differentiate true surface returns from extraneous reflections. Provisions have been included to monitor and record critical

D. D. Mawhinney; A. Presser; T. G. Koselke

1993-01-01

212

POC-scale testing of an advanced fine coal dewatering equipment/technique  

SciTech Connect

Froth flotation technique is an effective and efficient process for recovering of ultra-fine (minus 74 {mu}m) clean coal. Economical dewatering of an ultra-fine clean coal product to a 20 percent level moisture will be an important step in successful implementation of the advanced cleaning processes. This project is a step in the Department of Energy`s program to show that ultra-clean coal could be effectively dewatered to 20 percent or lower moisture using either conventional or advanced dewatering techniques. As the contract title suggests, the main focus of the program is on proof-of-concept testing of a dewatering technique for a fine clean coal product. The coal industry is reluctant to use the advanced fine coal recovery technology due to the non-availability of an economical dewatering process. in fact, in a recent survey conducted by U.S. DOE and Battelle, dewatering of fine clean coal was identified as the number one priority for the coal industry. This project will attempt to demonstrate an efficient and economic fine clean coal slurry dewatering process.

Groppo, J.G.; Parekh, B.K. [Univ. of Kentucky, Lexington, KY (United States); Rawls, P. [Department of Energy, Pittsburgh, PA (United States)

1995-11-01

213

The periodic MINDO molecular orbital method as a surface analytical technique  

NASA Astrophysics Data System (ADS)

In previous work we have shown that the periodic LUC-MINDO molecular orbital method with optimized parameters is able to yield a good description of the bulk electronic and elastic properties of the homopolar covalent solids, diamond and silicon. In this paper we consider the extension of this semi-empirical technique to the study of semiconductor surfaces. This surfacemodified, self-consistent molecular orbital method is shown to be a rapidly convergent, computationally viable surface analytical technique which is capable of treating thick slabs and far more complex systems than the corresponding first-principles techniques. When applied to the Si(100)-2 × 1 surface it is shown to correctly predict both the reconstruction (dimerization) of the surface, and the fact that the surface electronic structure is semiconducting. The paper concludes with a brief outline of some proposed applications for this promising technique.

Craig, B. I.; Smith, P. V.

1989-03-01

214

Theory of the Double-Edge Molecular Technique for Doppler Lidar Wind Measurement  

Microsoft Academic Search

The theory of the double-edge lidar technique for measuring the wind with molecular backscatter is described. Two high-spectral-resolution edge filters are located in the wings of the Rayleigh Brillouin profile. This doubles the signal change per unit Doppler shift, the sensitivity, and improves measurement accuracy relative to the single-edge technique by nearly a factor of 2. The use of a

Cristina Flesia; C. Laurence Korb

1999-01-01

215

Recent advances in discovery, heterologous expression, and molecular engineering of cyclodextrin glycosyltransferase for versatile applications.  

PubMed

Cyclodextrin glycosyltransferase (CGTase) is an important enzyme with multiple functions, in particular the production of cyclodextrins. It is also widely applied in baking and carbohydrate glycosylation because it participates in various types of catalytic reactions. New applications are being found with novel CGTases being isolated from various organisms. Heterologous expression is performed for the overproduction of CGTases to meet the requirements of these applications. In addition, various directed evolution techniques have been applied to modify the molecular structure of CGTase for improved performance in industrial applications. In recent years, substantial progress has been made in the heterologous expression and molecular engineering of CGTases. In this review, we systematically summarize the heterologous expression strategies used for enhancing the production of CGTases. We also outline and discuss the molecular engineering approaches used to improve the production, secretion, and properties (e.g., product and substrate specificity, catalytic efficiency, and thermal stability) of CGTase. PMID:24361954

Han, Ruizhi; Li, Jianghua; Shin, Hyun-Dong; Chen, Rachel R; Du, Guocheng; Liu, Long; Chen, Jian

2014-01-01

216

New strategies in ovarian cancer: translating the molecular complexity of ovarian cancer into treatment advances.  

PubMed

An improved understanding of the genomics of ovarian cancer and the separation of ovarian cancer into histologically and molecularly defined subgroups have affected drug development and clinical trial design in ovarian cancer. Active therapies that have been tested in ovarian cancer include agents that inhibit angiogenesis and poly (ADP-ribose) polymerase inhibitors (PARPi). However, no FDA drug approvals for ovarian cancer have been granted since 2006, and overall survival improvements have been difficult to achieve with new agents. The genomic complexity of ovarian cancer and modest single-agent activity of many biologic agents in this disease have led to testing of biologic agent combinations. In this article, we review recent advances in the understanding of the molecular diversity of ovarian cancer as well as emerging therapeutic strategies such as new agents and biologic combinations that attempt to target multiple aberrant pathways in this cancer. Clin Cancer Res; 20(20); 5150-6. ©2014 AACR. PMID:25320365

Liu, Joyce; Matulonis, Ursula A

2014-10-15

217

Effects of Molecular Structure in Macroscopic Mechanical Properties of an Advanced Polymer (LARC(sup TM)-SI)  

NASA Technical Reports Server (NTRS)

Mechanical testing of an advanced polymer resin with known variations in molecular weight was performed over a range of temperatures below the glass transition temperature. The elastic properties, inelastic elongation behavior, and notched tensile strength all as a function of molecular weight and test temperature were determined. It was shown that notched tensile strength is a strong function of both temperature and molecular weight, whereas stiffness is only a strong function of temperature.

Nicholson, Lee M.; Hinkley, Jeffrey A.; Whitley, Karen S.; Gates, Thomas S.

2004-01-01

218

Molecular techniques for the identification and detection of microorganisms relevant for the food industry  

Microsoft Academic Search

The research described in this thesis concerns the development and application in food microbiology of molecular identification and detection techniques based on 16S rRNA sequences. The technologies developed were applied to study the microbial ecology of two groups of bacteria, namely starter cultures and sporeforming spoilage bacteria, that are of importance to the food industry and in particular the dairy

N. Klijn

1996-01-01

219

Molecular techniques in the biotechnological fight against halogenated compounds in anoxic environments  

PubMed Central

Summary Microbial treatment of environmental contamination by anthropogenic halogenated organic compounds has become popular in recent decades, especially in the subsurface environments. Molecular techniques such as polymerase chain reaction?based fingerprinting methods have been extensively used to closely monitor the presence and activities of dehalogenating microbes, which also lead to the discovery of new dehalogenating bacteria and novel functional genes. Nowadays, traditional molecular techniques are being further developed and optimized for higher sensitivity, specificity, and accuracy to better fit the contexts of dehalogenation. On the other hand, newly developed high throughput techniques, such as microarray and next?generation sequencing, provide unsurpassed detection ability, which has enabled large?scale comparative genomic and whole?genome transcriptomic analysis. The aim of this review is to summarize applications of various molecular tools in the field of microbially mediated dehalogenation of various halogenated organic compounds. It is expected that traditional molecular techniques and nucleic?acid?based biomarkers will still be favoured in the foreseeable future because of relative low costs and high flexibility. Collective analyses of metagenomic sequencing data are still in need of information from individual dehalogenating strains and functional reductive dehalogenase genes in order to draw reliable conclusions. PMID:22070763

Ding, Chang; He, Jianzhong

2012-01-01

220

The use of molecular techniques to characterize the microbial communities in contaminated soil and water  

Microsoft Academic Search

Traditionally, the identification and characterization of microbial communities in contaminated soil and water has previously been limited to those microorganisms that are culturable. The application of molecular techniques to study microbial populations at contaminated sites without the need for culturing has led to the discovery of unique and previously unrecognized microorganisms as well as complex microbial diversity in contaminated soil

Seidu Malik; Michael Beer; Mallavarapu Megharaj; Ravi Naidu

2008-01-01

221

Rapid molecular technique for identification of a biological control agent Rhodosporidium diobovatum  

Microsoft Academic Search

The purpose of this study was to develop a rapid molecular technique for identification of the biological control agent, Rhodosporidium diobovatum. DNA from all yeast cultures described below was extracted, amplified by PCR using primers specific to septate fungi, and fixed to nylon membranes. Using sequence information obtained from the GenBank database, Rhodosporidium diobovatum-specific oligonucleotides were designed and, after labeling

Y. Cao; R. S. Utkhede

2005-01-01

222

Accelerated Testing Methodology in Constant Stress-Rate Testing for Advanced Structural Ceramics: A Preloading Technique  

NASA Technical Reports Server (NTRS)

Preloading technique was used as a means of an accelerated testing methodology in constant stress-rate ('dynamic fatigue') testing for two different brittle materials. The theory developed previously for fatigue strength as a function of preload was further verified through extensive constant stress-rate testing for glass-ceramic and CRT glass in room temperature distilled water. The preloading technique was also used in this study to identify the prevailing failure mechanisms at elevated temperatures, particularly at lower test rate in which a series of mechanisms would be associated simultaneously with material failure, resulting in significant strength increase or decrease. Two different advanced ceramics including SiC whisker-reinforced composite silicon nitride and 96 wt% alumina were used at elevated temperatures. It was found that the preloading technique can be used as an additional tool to pinpoint the dominant failure mechanism that is associated with such a phenomenon of considerable strength increase or decrease.

Choi, Sung R.; Gyekenyesi, John P.; Huebert, Dean; Bartlett, Allen; Choi, Han-Ho

2001-01-01

223

Molecular Technique to Reduce PCR Bias for Deeper Understanding of Microbial Diversity  

NASA Technical Reports Server (NTRS)

Current planetary protection policies require that spacecraft targeted to sensitive solar system bodies be assembled and readied for launch in controlled cleanroom environments. A better understanding of the distribution and frequency at which high-risk contaminant microbes are encountered on spacecraft surfaces would significantly aid in assessing the threat of forward contamination. However, despite a growing understanding of the diverse microbial populations present in cleanrooms, less abundant microbial populations are probably not adequately taken into account due to technological limitations. This novel approach encompasses a wide spectrum of microbial species and will represent the true picture of spacecraft cleanroom-associated microbial diversity. All of the current microbial diversity assessment techniques are based on an initial PCR amplification step. However, a number of factors are known to bias PCR amplification and jeopardize the true representation of bacterial diversity. PCR amplification of a minor template appears to be suppressed by the amplification of a more abundant template. It is widely acknowledged among environmental molecular microbiologists that genetic biosignatures identified from an environment only represent the most dominant populations. The technological bottleneck overlooks the presence of the less abundant minority population and may underestimate their role in the ecosystem maintenance. DNA intercalating agents such as propidium monoazide (PMA) covalently bind with DNA molecules upon photolysis using visible light, and make it unavailable for DNA polymerase enzyme during polymerase chain reaction (PCR). Environmental DNA samples will be treated with suboptimum PMA concentration, enough to intercalate with 90 99% of the total DNA. The probability of PMA binding with DNA from abundant bacterial species will be much higher than binding with DNA from less abundant species. This will increase the relative DNA concentration of previously "shadowed" less abundant species available for PCR amplification. These PCR products obtained with and without PMA treatment will then be subjected to downstream diversity analyses such as sequencing and DNA microarray. It is expected that PMA-coupled PCR will amplify the "minority population" and help in understanding microbial diversity spectrum of an environmental sample at a much deeper level. This new protocol aims to overcome the major potential biases faced when analyzing microbial 16S rRNA gene diversity. This study will lead to a technological advancement and a commercial product that will aid microbial ecologists in understanding microbial diversity from various environmental niches. Implementation of this technique may lead to discoveries of novel microbes and their functions in sustenance of the ecosystem.

Vaishampayan, Parag A.; Venkateswaran, Kasthuri J.

2012-01-01

224

Review of recent advances in analytical techniques for the determination of neurotransmitters  

PubMed Central

Methods and advances for monitoring neurotransmitters in vivo or for tissue analysis of neurotransmitters over the last five years are reviewed. The review is organized primarily by neurotransmitter type. Transmitter and related compounds may be monitored by either in vivo sampling coupled to analytical methods or implanted sensors. Sampling is primarily performed using microdialysis, but low-flow push-pull perfusion may offer advantages of spatial resolution while minimizing the tissue disruption associated with higher flow rates. Analytical techniques coupled to these sampling methods include liquid chromatography, capillary electrophoresis, enzyme assays, sensors, and mass spectrometry. Methods for the detection of amino acid, monoamine, neuropeptide, acetylcholine, nucleoside, and soluable gas neurotransmitters have been developed and improved upon. Advances in the speed and sensitivity of these methods have enabled improvements in temporal resolution and increased the number of compounds detectable. Similar advances have enabled improved detection at tissue samples, with a substantial emphasis on single cell and other small samples. Sensors provide excellent temporal and spatial resolution for in vivo monitoring. Advances in application to catecholamines, indoleamines, and amino acids have been prominent. Improvements in stability, sensitivity, and selectivity of the sensors have been of paramount interest. PMID:19800472

Perry, Maura; Li, Qiang; Kennedy, Robert T.

2009-01-01

225

System engineering techniques for establishing balanced design and performance guidelines for the advanced telerobotic testbed  

NASA Technical Reports Server (NTRS)

Novel system engineering techniques have been developed and applied to establishing structured design and performance objectives for the Telerobotics Testbed that reduce technical risk while still allowing the testbed to demonstrate an advancement in state-of-the-art robotic technologies. To estblish the appropriate tradeoff structure and balance of technology performance against technical risk, an analytical data base was developed which drew on: (1) automation/robot-technology availability projections, (2) typical or potential application mission task sets, (3) performance simulations, (4) project schedule constraints, and (5) project funding constraints. Design tradeoffs and configuration/performance iterations were conducted by comparing feasible technology/task set configurations against schedule/budget constraints as well as original program target technology objectives. The final system configuration, task set, and technology set reflected a balanced advancement in state-of-the-art robotic technologies, while meeting programmatic objectives and schedule/cost constraints.

Zimmerman, W. F.; Matijevic, J. R.

1987-01-01

226

Extrusion based rapid prototyping technique: an advanced platform for tissue engineering scaffold fabrication.  

PubMed

Advances in scaffold design and fabrication technology have brought the tissue engineering field stepping into a new era. Conventional techniques used to develop scaffolds inherit limitations, such as lack of control over the pore morphology and architecture as well as reproducibility. Rapid prototyping (RP) technology, a layer-by-layer additive approach offers a unique opportunity to build complex 3D architectures overcoming those limitations that could ultimately be tailored to cater for patient-specific applications. Using RP methods, researchers have been able to customize scaffolds to mimic the biomechanical properties (in terms of structural integrity, strength, and microenvironment) of the organ or tissue to be repaired/replaced quite closely. This article provides intensive description on various extrusion based scaffold fabrication techniques and review their potential utility for TE applications. The extrusion-based technique extrudes the molten polymer as a thin filament through a nozzle onto a platform layer-by-layer and thus building 3D scaffold. The technique allows full control over pore architecture and dimension in the x- and y- planes. However, the pore height in z-direction is predetermined by the extruding nozzle diameter rather than the technique itself. This review attempts to assess the current state and future prospects of this technology. PMID:21830198

Hoque, M Enamul; Chuan, Y Leng; Pashby, Ian

2012-02-01

227

Advances in gas-mediated electron beam-induced etching and related material processing techniques  

NASA Astrophysics Data System (ADS)

Electron beam-induced etching (EBIE) has traditionally been used for top-down, direct-write, chemical dry etching, and iterative editing of materials. The present article reviews recent advances in EBIE modeling and emerging applications, with an emphasis on use cases in which the approaches that have conventionally been used to realize EBIE are instead used for material analysis, surface functionalization, or bottom-up growth of nanostructured materials. Such applications are used to highlight the shortcomings of existing quantitative EBIE models and to identify physicochemical phenomena that must be accounted for in order to enable full exploitation and predictive modeling of EBIE and related electron beam fabrication techniques.

Toth, Milos

2014-07-01

228

Techniques for measurement of the thermal expansion of advanced composite materials  

NASA Technical Reports Server (NTRS)

Techniques available to measure small thermal displacements in flat laminates and structural tubular elements of advanced composite materials are described. Emphasis is placed on laser interferometry and the laser interferometric dilatometer system used at the National Aeronautics and Space Administration (NASA) Langley Research Center. Thermal expansion data are presented for graphite-fiber reinforced 6061 and 2024 aluminum laminates and for graphite fiber reinforced AZ91 C and QH21 A magnesium laminates before and after processing to minimize or eliminate thermal strain hysteresis. Data are also presented on the effects of reinforcement volume content on thermal expansion of silicon-carbide whisker and particulate reinforced aluminum.

Tompkins, Stephen S.

1989-01-01

229

Predictive molecular markers in metastases to the central nervous system: recent advances and future avenues.  

PubMed

Metastases to the central nervous system (CNS) are common in several cancer types. For most primary tumors that commonly metastasize to the CNS, molecular biomarker analyses are recommended in the clinical setting for selection of appropriate targeted therapies. Therapeutic efficacy of some of these agents has been documented in patients with brain metastases, and molecular testing of CNS metastases should be considered in the clinical setting. Here, we summarize the clinically relevant biomarker tests that should be considered in neurosurgical specimens based on the current recommendations of the European Society of Medical Oncology (ESMO) or the National Comprehensive Cancer Network (NCCN) for the most relevant primary tumor types: lung cancer (EGFR mutations, ALK rearrangement, BRAF mutations), breast cancer (HER2 amplification, steroid receptor overexpression), melanoma (BRAF mutations), and colorectal cancer (RAS mutations). Furthermore, we discuss emerging therapeutic targets including novel oncogenic alterations (ROS1 rearrangements, FGFR1 amplifications, CMET amplifications, and others) and molecular features of the tumor microenvironment (including immune-checkpoint molecules such as CTLA4 and PD-1/PD-L1). We also discuss the potential role of advanced biomarker tests such as next-generation sequencing and "liquid biopsies" for patients with CNS metastases. PMID:25287912

Berghoff, Anna Sophie; Bartsch, Rupert; Wöhrer, Adelheid; Streubel, Berthold; Birner, Peter; Kros, Johan M; Brastianos, Priscilla K; von Deimling, Andreas; Preusser, Matthias

2014-12-01

230

Biosynthesis of Polyunsaturated Fatty Acids in Marine Invertebrates: Recent Advances in Molecular Mechanisms  

PubMed Central

Virtually all polyunsaturated fatty acids (PUFA) originate from primary producers but can be modified by bioconversions as they pass up the food chain in a process termed trophic upgrading. Therefore, although the main primary producers of PUFA in the marine environment are microalgae, higher trophic levels have metabolic pathways that can produce novel and unique PUFA. However, little is known about the pathways of PUFA biosynthesis and metabolism in the levels between primary producers and fish that are largely filled by invertebrates. It has become increasingly apparent that, in addition to trophic upgrading, de novo synthesis of PUFA is possible in some lower animals. The unequivocal identification of PUFA biosynthetic pathways in many invertebrates is complicated by the presence of other organisms within them. These organisms include bacteria and algae with PUFA biosynthesis pathways, and range from intestinal flora to symbiotic relationships that can involve PUFA translocation to host organisms. This emphasizes the importance of studying biosynthetic pathways at a molecular level, and the continual expansion of genomic resources and advances in molecular analysis is facilitating this. The present paper highlights recent research into the molecular and biochemical mechanisms of PUFA biosynthesis in marine invertebrates, particularly focusing on cephalopod molluscs. PMID:24152561

Monroig, Oscar; Tocher, Douglas R.; Navarro, Juan C.

2013-01-01

231

Molecular Techniques for Detection, Species Differentiation, and Phylogenetic Analysis of Microsporidia  

PubMed Central

Microsporidia are obligate intracellular protozoan parasites that infect a broad range of vertebrates and invertebrates. These parasites are now recognized as one of the most common pathogens in human immunodeficiency virus-infected patients. For most patients with infectious diseases, microbiological isolation and identification techniques offer the most rapid and specific determination of the etiologic agent. This is not a suitable procedure for microsporidia, which are obligate intracellular parasites requiring cell culture systems for growth. Therefore, the diagnosis of microsporidiosis currently depends on morphological demonstration of the organisms themselves. Although the diagnosis of microsporidiosis and identification of microsporidia by light microscopy have greatly improved during the last few years, species differentiation by these techniques is usually impossible and transmission electron microscopy may be necessary. Immunfluorescent-staining techniques have been developed for species differentiation of microsporidia, but the antibodies used in these procedures are available only at research laboratories at present. During the last 10 years, the detection of infectious disease agents has begun to include the use of nucleic acid-based technologies. Diagnosis of infection caused by parasitic organisms is the last field of clinical microbiology to incorporate these techniques and molecular techniques (e.g., PCR and hybridization assays) have recently been developed for the detection, species differentiation, and phylogenetic analysis of microsporidia. In this paper we review human microsporidial infections and describe and discuss these newly developed molecular techniques. PMID:10194459

Franzen, Caspar; Muller, Andreas

1999-01-01

232

Individual Particle Analysis of Ambient PM 2.5 Using Advanced Electron Microscopy Techniques  

SciTech Connect

The overall goal of this project was to demonstrate a combination of advanced electron microscopy techniques that can be effectively used to identify and characterize individual particles and their sources. Specific techniques to be used include high-angle annular dark field scanning transmission electron microscopy (HAADF-STEM), STEM energy dispersive X-ray spectrometry (EDX), and energy-filtered TEM (EFTEM). A series of ambient PM{sub 2.5} samples were collected in communities in southwestern Detroit, MI (close to multiple combustion sources) and Steubenville, OH (close to several coal fired utility boilers). High-resolution TEM (HRTEM) -imaging showed a series of nano-metal particles including transition metals and elemental composition of individual particles in detail. Submicron and nano-particles with Al, Fe, Ti, Ca, U, V, Cr, Si, Ba, Mn, Ni, K and S were observed and characterized from the samples. Among the identified nano-particles, combinations of Al, Fe, Si, Ca and Ti nano-particles embedded in carbonaceous particles were observed most frequently. These particles showed very similar characteristics of ultrafine coal fly ash particles that were previously reported. By utilizing HAADF-STEM, STEM-EDX, and EF-TEM, this investigation was able to gain information on the size, morphology, structure, and elemental composition of individual nano-particles collected in Detroit and Steubenville. The results showed that the contributions of local combustion sources - including coal fired utilities - to ultrafine particle levels were significant. Although this combination of advanced electron microscopy techniques by itself can not identify source categories, these techniques can be utilized as complementary analytical tools that are capable of providing detailed information on individual particles.

Gerald J. Keeler; Masako Morishita

2006-12-31

233

Recent Advances and New Techniques in Visualization of Ultra-short Relativistic Electron Bunches  

SciTech Connect

Ultrashort electron bunches with rms length of {approx} 1 femtosecond (fs) can be used to generate ultrashort x-ray pulses in FELs that may open up many new regimes in ultrafast sciences. It is also envisioned that ultrashort electron bunches may excite {approx}TeV/m wake fields for plasma wake field acceleration and high field physics studies. Recent success of using 20 pC electron beam to drive an x-ray FEL at LCLS has stimulated world-wide interests in using low charge beam (1 {approx} 20 pC) to generate ultrashort x-ray pulses (0.1 fs {approx} 10 fs) in FELs. Accurate measurement of the length (preferably the temporal profile) of the ultrashort electron bunch is essential for understanding the physics associated with the bunch compression and transportation. However, the shorter and shorter electron bunch greatly challenges the present beam diagnostic methods. In this paper we review the recent advances in the measurement of ultra-short electron bunches. We will focus on several techniques and their variants that provide the state-of-the-art temporal resolution. Methods to further improve the resolution of these techniques and the promise to break the 1 fs time barrier is discussed. We review recent advances in the measurement of ultrashort relativistic electron bunches. We will focus on several techniques and their variants that are capable of breaking the femtosecond time barrier in measurements of ultrashort bunches. Techniques for measuring beam longitudinal phase space as well as the x-ray pulse shape in an x-ray FEL are also discussed.

Xiang, Dao; /SLAC

2012-06-05

234

The application of molecular and modern cell biological techniques is beginning to show that the classical picture of  

E-print Network

458 The application of molecular and modern cell biological techniques is beginning to show eukaryotic organisms. Meiosis has been described by cytologists over many decades, but recently modern cell biological and genetic techniques have been applied to the analysis of the fundamental molecular mechanisms

Shaw, Peter

235

[Which molecular biology techniques must conform to the armamentarium for basic research in uro-oncology?].  

PubMed

Molecular biology has been one of the scientific disciplines in which there has been more advances in the last years. The first impulse in the study of genetic alterations came from the discovery of DNA structure, followed by elucidation of the genetic code, the discovery of restriction enzymes and subsequently the invention of PCR, not forgetting the exponential development of computer science. All of them have allowed us to know much more about our genome and its regulation than we could imagine. The impulse in proteomics has been especially in tune up of soft methods of ionization coupled with mass spectrometry. Nevertheless, this seems to be only the beginning since today there are continuous methodological advances that will increase more, without doubt, the knowledge and applications in this discipline. PMID:23793758

Oriola, Josep

2013-06-01

236

The role of molecular techniques in the understanding of emerging infections.  

PubMed

Emerging infections are defined as infections that are newly identified or recognized, or those whose incidence in humans has significantly increased over the past 20 years. The interaction of several factors contributes to the emergence of infectious disease, including changes in human behavior, technological advances, economic development, increased international travel, microbial adaptation and lapses in public health measures. Biomedical research has allowed us to identify and classify previously uncultured pathogens, characterize microbial virulence factors, create new diagnostic tests and develop vaccines. Here, we highlight a few emerging infections and illustrate the role that molecular medicine has played in furthering our understanding of these diseases. PMID:8796869

Sable, C A; Mandell, G L

1996-03-01

237

Data requirements for advancing techniques to predict dredge-induced sediment and contaminant releases -- A review  

SciTech Connect

In many areas of the world, contaminated sediments are being considered a major factor in the redistribution of toxic chemicals in the environment. While removal of contaminated sediments from the aquatic environment is often the preferred alternative for reducing the potential impacts of contaminated sediment, regulatory agencies and the public often express concern about contaminant releases during dredging operations. The US Army Corps of Engineers continues to develop techniques for making a priori estimates of the sediment resuspension rates and contaminant releases during hydraulic and mechanical dredging activities. However, appropriate field data to verify and refine these techniques for a wide range of conditions are currently limited. Data needs include physical and operational characteristics of the dredge, waterway characteristics, sediment characteristics, sediment contaminant data, and water quality data collected during the dredging activity. This paper discusses key parameters required to improve the current predictive techniques and outlines the type of monitoring program needed to improve the comparability of the techniques to measured releases. The recommended monitoring program is derived from experiences with previous monitoring efforts. Planners of future dredging demonstrations are encouraged to collect similar data in order to advance the state of the art for predicting sediment and contaminant releases associated with dredging.

Averett, D.E. [Army Corps of Engineers, Vicksburg, MS (United States). Waterways Experiment Station

1995-12-31

238

Advanced techniques for array processing. Final report, 1 Mar 89-30 Apr 91  

SciTech Connect

Array processing technology is expected to be a key element in communication systems designed for the crowded and hostile environment of the future battlefield. While advanced array processing techniques have been under development for some time, their practical use has been very limited. This project addressed some of the issues which need to be resolved for a successful transition of these promising techniques from theory into practice. The main problem which was studied was that of finding the directions of multiple co-channel transmitters from measurements collected by an antenna array. Two key issues related to high-resolution direction finding were addressed: effects of system calibration errors, and effects of correlation between the received signals due to multipath propagation. A number of useful theoretical performance analysis results were derived, and computationally efficient direction estimation algorithms were developed. These results include: self-calibration techniques for antenna arrays, sensitivity analysis for high-resolution direction finding, extensions of the root-MUSIC algorithm to arbitrary arrays and to arrays with polarization diversity, and new techniques for direction finding in the presence of multipath based on array interpolation. (Author)

Friedlander, B.

1991-05-30

239

Advanced fluorescence microscopy techniques--FRAP, FLIP, FLAP, FRET and FLIM.  

PubMed

Fluorescence microscopy provides an efficient and unique approach to study fixed and living cells because of its versatility, specificity, and high sensitivity. Fluorescence microscopes can both detect the fluorescence emitted from labeled molecules in biological samples as images or photometric data from which intensities and emission spectra can be deduced. By exploiting the characteristics of fluorescence, various techniques have been developed that enable the visualization and analysis of complex dynamic events in cells, organelles, and sub-organelle components within the biological specimen. The techniques described here are fluorescence recovery after photobleaching (FRAP), the related fluorescence loss in photobleaching (FLIP), fluorescence localization after photobleaching (FLAP), Förster or fluorescence resonance energy transfer (FRET) and the different ways how to measure FRET, such as acceptor bleaching, sensitized emission, polarization anisotropy, and fluorescence lifetime imaging microscopy (FLIM). First, a brief introduction into the mechanisms underlying fluorescence as a physical phenomenon and fluorescence, confocal, and multiphoton microscopy is given. Subsequently, these advanced microscopy techniques are introduced in more detail, with a description of how these techniques are performed, what needs to be considered, and what practical advantages they can bring to cell biological research. PMID:22469598

Ishikawa-Ankerhold, Hellen C; Ankerhold, Richard; Drummen, Gregor P C

2012-01-01

240

A multiscale modeling technique for bridging molecular dynamics with finite element method  

NASA Astrophysics Data System (ADS)

In computational mechanics, molecular dynamics (MD) and finite element (FE) analysis are well developed and most popular on nanoscale and macroscale analysis, respectively. MD can very well simulate the atomistic behavior, but cannot simulate macroscale length and time due to computational limits. FE can very well simulate continuum mechanics (CM) problems, but has the limitation of the lack of atomistic level degrees of freedom. Multiscale modeling is an expedient methodology with a potential to connect different levels of modeling such as quantum mechanics, molecular dynamics, and continuum mechanics. This study proposes a new multiscale modeling technique to couple MD with FE. The proposed method relies on weighted average momentum principle. A wave propagation example has been used to illustrate the challenges in coupling MD with FE and to verify the proposed technique. Furthermore, 2-Dimensional problem has also been used to demonstrate how this method would translate into real world applications.

Lee, Yongchang; Basaran, Cemal

2013-11-01

241

Nonlinear Raman Techniques in Femtosecond Time Resolved Spectroscopy for the Analysis and Control of Molecular Dynamics  

SciTech Connect

The use of four-wave mixing techniques in femtosecond time-resolved spectroscopy has considerable advantages. Due to the many degrees of freedom offered e.g. by coherent anti-Stokes Raman scattering (CARS), the dynamics even of complex systems can be analyzed in detail. Using pulse shaping techniques in combination with a self-learning loop approach, molecular mode excitation can be controlled very efficiently in a multi-photon excitation process. Results obtained from the optimal control of CARS on {beta}-carotene are discussed.

Materny, Arnulf; Konradi, Jakow; Namboodiri, Vinu; Namboodiri, Mahesh; Scaria, Abraham [Jacobs University Bremen, School of Science and Engineering Campus Ring 1, 28759 Bremen (Germany)

2008-11-14

242

Advancing the education in molecular diagnostics: the IFCC-Initiative "Clinical Molecular Biology Curriculum" (C-CMBC); a ten-year experience.  

PubMed

Molecular techniques are becoming commonplace in the diagnostic laboratory. Their applications influence all major phases of laboratory medicine including predisposition/genetic risk, primary diagnosis, therapy stratification and prognosis. Readily available laboratory hardware and wetware (i.e. consumables and reagents) foster rapid dissemination to countries that are just establishing molecular testing programs. Appropriate skill levels extending beyond the technical procedure are required for analytical and diagnostic proficiency that is mandatory in molecular genetic testing. An international committee (C-CMBC) of the International Federation for Clinical Chemistry (IFCC) was established to disseminate skills in molecular genetic testing in member countries embarking on the respective techniques. We report the ten-year experience with different teaching and workshop formats for beginners in molecular diagnostics. PMID:24815033

Lianidou, Evi; Ahmad-Nejad, Parviz; Ferreira-Gonzalez, Andrea; Izuhara, Kenji; Cremonesi, Laura; Schroeder, Maria-Eugenia; Richter, Karin; Ferrari, Maurizio; Neumaier, Michael

2014-09-25

243

[The HRM-new molecular technique of detection of pharmaceutical resistance of micobacteria of tuberculosis].  

PubMed

The early detection of isolates of mycobacterium of tuberculosis resistant to anti-tuberculosis pharmaceuticals is ultimately needed for optimization of treatment scheme and prevention of propagation of resistant strains. The literature review presents analysis of data concerning the new, fast and inexpensive technique of detection of mutations in genes of mycobacterium of tuberculosis competent for multiple medicinal resistance. The molecular genetic technique HRM (high resolution melting curve analysis) is based on implementation of amplification of DNA fragments with subsequent analysis of their curves of melting with high resolution. The technique demonstrated its high sensitivity and specificity. In contrast with other molecular genetic techniques of detection of resistance of mycobacterium of tuberculosis, the makes it possible to detect all mutations in interested fragments of genes and to distinguish DNA of mutant and wild types in their mixture. This technique has no contamination danger. The HRM-analysis can become a basis for development of diagnostic kits with purpose to detect tuberculosis with multiple medicinal resistance. PMID:25346992

2014-07-01

244

Evaluation of combined morphological and molecular techniques for marine nematode ( Terschellingia spp.) identification  

Microsoft Academic Search

Marine nematodes, which play an important role in many ecosystems, include a number of apparently cosmopolitan taxa that exhibit\\u000a broad biogeographic ranges even though there is no obvious dispersal phase in their lifecycle. In this study, standard taxonomic\\u000a approaches to marine nematode identification in conjunction with multivariate statistical analysis of morphometric data were\\u000a compared with molecular techniques. Specimens of the

P. Bhadury; M. C. Austen; D. T. Bilton; P. J. D. Lambshead; A. D. Rogers; G. R. Smerdon

2008-01-01

245

Molecularly targeted therapies for advanced or metastatic non-small-cell lung carcinoma  

PubMed Central

Non-small-cell lung cancer (NSCLC) remains the leading cause of cancer-related death in both men and women in the United States. Platinum-based doublet chemotherapy has been a standard for patients with advanced stage disease. Improvements in overall survival and quality of life have been modest. Improved knowledge of the aberrant molecular signaling pathways found in NSCLC has led to the development of biomarkers with associated targeted therapeutics, thus changing the treatment paradigm for many NSCLC patients. In this review, we present a summary of many of the currently investigated biologic targets in NSCLC, discuss their current clinical trial status, and also discuss the potential for development of other targeted agents. PMID:23696960

Bayraktar, Soley; Rocha-Lima, Caio M

2013-01-01

246

Recent advances in tumor hypoxia: tumor progression, molecular mechanisms, and therapeutic implications.  

PubMed

Tumor oxygenation status is tightly regulated and correlates with its aggressive behavior. Hypoxia plays critical roles in tumor progression including tumor angiogenesis, mutation rate, metastasis and resistance to radiation and chemotherapy. Many molecular pathways have been recognized to mediate these hypoxia-induced responses in tumors. For example, extensive studies demonstrate that hypoxia-inducible factor-1 (HIF-1) is a key molecule in regulating tumor responses to hypoxia. Many other genes including growth factors, glycolytic enzymes, cytokines, and transcription factors are inducible by hypoxia via either HIF-1-dependent or HIF-1-independent pathways. This review summarizes current advances in tumor hypoxia regarding new technologies of tumor hypoxia measurement, clinical and animal studies, cell culture models, the hypoxia-induced key molecules and therapeutic implications. This valuable information is particularly timely and helpful for clinicians and researchers who want to recognize the newest endeavors within the field and identify possible lines of investigation in tumor hypoxia. PMID:17901861

Zhang, Yuqing; Li, Min; Yao, Qizhi; Chen, Changyi

2007-10-01

247

Molecular entomology and prospects for malaria control  

Microsoft Academic Search

During the past decade, the techniques of molecular and cell biology have been embraced by many scientists doing research on anopheline vectors of malaria parasites. Some of the most important research advances in molecular entomology have concerned the development of sophisticated molecular tools for procedures such as genetic and physical mapping and germ line transformation. Major advances have also been

Frank H. Collins; Luna Kamau; Hilary A. Ranson; John M. Vulule

2000-01-01

248

Advanced contrast nanoagents for photoacoustic molecular imaging, cytometry, blood test and photothermal theranostics.  

PubMed

Various nanoparticles have raised significant interest over the past decades for their unique physical and optical properties and biological utilities. Here we summarize the vast applications of advanced nanoparticles with a focus on carbon nanotube (CNT)-based or CNT-catalyzed contrast agents for photoacoustic (PA) imaging, cytometry and theranostics applications based on the photothermal (PT) effect. We briefly review the safety and potential toxicity of the PA/PT contrast nanoagents, while showing how the physical properties as well as multiple biological coatings change their toxicity profiles and contrasts. We provide general guidelines needed for the validation of a new molecular imaging agent in living subjects, and exemplify these guidelines with single-walled CNTs targeted to ?(v) ?(3) , an integrin associated with tumor angiogenesis, and golden carbon nanotubes targeted to LYVE-1, endothelial lymphatic receptors. An extensive review of the potential applications of advanced contrast agents is provided, including imaging of static targets such as tumor angiogenesis receptors, in vivo cytometry of dynamic targets such as circulating tumor cells and nanoparticles in blood, lymph, bones and plants, methods to enhance the PA and PT effects with transient and stationary bubble conjugates, PT/PA Raman imaging and multispectral histology. Finally, theranostic applications are reviewed, including the nanophotothermolysis of individual tumor cells and bacteria with clustered nanoparticles, nanothrombolysis of blood clots, detection and purging metastasis in sentinel lymph nodes, spectral hole burning and multiplex therapy with ultrasharp rainbow nanoparticles. PMID:22025336

de la Zerda, Adam; Kim, Jin-Woo; Galanzha, Ekaterina I; Gambhir, Sanjiv S; Zharov, Vladimir P

2011-01-01

249

Advances in the field of high-molecular-weight polycyclic aromatic hydrocarbon biodegradation by bacteria  

PubMed Central

Summary Interest in understanding prokaryotic biotransformation of high?molecular?weight polycyclic aromatic hydrocarbons (HMW PAHs) has continued to grow and the scientific literature shows that studies in this field are originating from research groups from many different locations throughout the world. In the last 10 years, research in regard to HMW PAH biodegradation by bacteria has been further advanced through the documentation of new isolates that represent diverse bacterial types that have been isolated from different environments and that possess different metabolic capabilities. This has occurred in addition to the continuation of in?depth comprehensive characterizations of previously isolated organisms, such as Mycobacterium vanbaalenii PYR?1. New metabolites derived from prokaryotic biodegradation of four? and five?ring PAHs have been characterized, our knowledge of the enzymes involved in these transformations has been advanced and HMW PAH biodegradation pathways have been further developed, expanded upon and refined. At the same time, investigation of prokaryotic consortia has furthered our understanding of the capabilities of microorganisms functioning as communities during HMW PAH biodegradation. PMID:21255317

Kanaly, Robert A.; Harayama, Shigeaki

2010-01-01

250

Advances in molecular methods to alter chromosomes and genome in the yeast Saccharomyces cerevisiae.  

PubMed

A fundamental issue in biotechnology is how to breed useful strains of microorganisms for efficient production of valuable biomaterials. On-going and more recent developments in gene manipulation technologies and chromosomal and genomic modifications in particular have facilitated important contributions in this area. "Chromosome manipulation technology" as an outgrowth of "gene manipulation technology" may provide opportunities for creating novel strains of organisms with a variety of genomic constitutions. A simple and rapid chromosome splitting technology called "PCR-mediated chromosome splitting" (PCS) that we recently developed has made it possible to manipulate chromosomes and genomes on a large scale in an industrially important microorganism, Saccharomyces cerevisiae. This paper focuses on recent advances in molecular methods for altering chromosomes and genome in S. cerevisiae featuring chromosome splitting technology. These advances in introducing large-scale genomic modifications are expected to accelerate the breeding of novel strains for biotechnological purposes, and to reveal functions of presently uncharacterized chromosomal regions in S. cerevisiae and other organisms. PMID:19685240

Sugiyama, Minetaka; Yamagishi, Kazuo; Kim, Yeon-Hee; Kaneko, Yoshinobu; Nishizawa, Masafumi; Harashima, Satoshi

2009-10-01

251

New advanced surface modification technique: titanium oxide ceramic surface implants: long-term clinical results  

NASA Astrophysics Data System (ADS)

The purpose of this paper is to discuss the background to advanced surface modification technologies and to present a new technique, involving the formation of a titanium oxide ceramic coating, with relatively long-term results of its clinical utilization. Three general techniques are used to modify surfaces: the addition or removal of material and the change of material already present. Surface properties can also be changed without the addition or removal of material, through the laser or electron beam thermal treatment. The new technique outlined in this paper relates to the production of a corrosion-resistant 2000-2500 A thick, ceramic oxide layer with a coherent crystalline structure on the surface of titanium implants. The layer is grown electrochemically from the bulk of the metal and is modified by heat treatment. Such oxide ceramic-coated implants have a number of advantageous properties relative to implants covered with various other coatings: a higher external hardness, a greater force of adherence between the titanium and the oxide ceramic coating, a virtually perfect insulation between the organism and the metal (no possibility of metal allergy), etc. The coated implants were subjected to various physical, chemical, electronmicroscopic, etc. tests for a qualitative characterization. Finally, these implants (plates, screws for maxillofacial osteosynthesis and dental root implants) were applied in surgical practice for a period of 10 years. Tests and the experience acquired demonstrated the good properties of the titanium oxide ceramic-coated implants.

Szabo, Gyorgy; Kovacs, Lajos; Barabas, Jozsef; Nemeth, Zsolt; Maironna, Carlo

2001-11-01

252

Advances in Resistive Pulse Sensors: Devices bridging the void between molecular and microscopic detection  

PubMed Central

Since the first reported use of a biological ion channel to detect differences in single stranded genomic base pairs in 1996, a renaissance in nanoscale resistive pulse sensors has ensued. This resurgence of a technique originally outlined and commercialized over fifty years ago has largely been driven by advances in nanoscaled fabrication, and ultimately, the prospect of a rapid and inexpensive means for genomic sequencing as well as other macromolecular characterization. In this pursuit, the potential application of these devices to characterize additional properties such as the size, shape, charge, and concentration of nanoscaled materials (10 – 900 nm) has been largely overlooked. Advances in nanotechnology and biotechnology are driving the need for simple yet sensitive individual object readout devices such as resistive pulse sensors. This review will examine the recent progress in pore-based sensing in the nanoscale range. A detailed analysis of three new types of pore sensors – in-series, parallel, and size-tunable pores – has been included. These pores offer improved measurement sensitivity over a wider particle size range. The fundamental physical chemistry of these techniques, which is still evolving, will be reviewed. PMID:22034585

Kozak, Darby; Anderson, Will; Vogel, Robert; Trau, Matt

2011-01-01

253

Abstract--Software modules of an advanced vehicle can be updated using Remote Software Upload (RSU) techniques. The  

E-print Network

Abstract-- Software modules of an advanced vehicle can be updated using Remote Software Upload (RSU) techniques. The RSU employs infrastructure-based wireless communication technique where the software supplier sends the software to the targeted vehicle via a roadside Base Station (BS). However, security

Mahmud, Syed Masud

254

Advances in surface magnetic field measurement technique for detection and sizing of surface-breaking cracks in offshore structures  

SciTech Connect

In detecting and sizing cracks in metal structures, the two common techniques of eddy-current and potential-drop, suffer from a number of problems which may not be acceptable in offshore environments. This paper describes recent advances in the surface magnetic field measurement (SMFM) technique as an alternative method for integrity evaluation of offshore metal structures.

Mirshekar-Syahkal, D. [Univ. of Essex, Colchester (United Kingdom); Sadeghi, S.H.H. [Amirkabir Univ., Tehran (Iran, Islamic Republic of)

1994-12-31

255

Genetics of hypertrophic cardiomyopathy: advances and pitfalls in molecular diagnosis and therapy  

PubMed Central

Hypertrophic cardiomyopathy (HCM) is a primary disease of the cardiac muscle that occurs mainly due to mutations (>1,400 variants) in genes encoding for the cardiac sarcomere. HCM, the most common familial form of cardiomyopathy, affecting one in every 500 people in the general population, is typically inherited in an autosomal dominant pattern, and presents variable expressivity and age-related penetrance. Due to the morphological and pathological heterogeneity of the disease, the appearance and progression of symptoms is not straightforward. Most HCM patients are asymptomatic, but up to 25% develop significant symptoms, including chest pain and sudden cardiac death. Sudden cardiac death is a dramatic event, since it occurs without warning and mainly in younger people, including trained athletes. Molecular diagnosis of HCM is of the outmost importance, since it may allow detection of subjects carrying mutations on HCM-associated genes before development of clinical symptoms of HCM. However, due to the genetic heterogeneity of HCM, molecular diagnosis is difficult. Currently, there are mainly four techniques used for molecular diagnosis of HCM, including Sanger sequencing, high resolution melting, mutation detection using DNA arrays, and next-generation sequencing techniques. Application of these methods has proven successful for identification of mutations on HCM-related genes. This review summarizes the features of these technologies, highlighting their strengths and weaknesses. Furthermore, current therapeutics for HCM patients are correlated with clinically observed phenotypes and are based on the alleviation of symptoms. This is mainly due to insufficient knowledge on the mechanisms involved in the onset of HCM. Tissue engineering alongside regenerative medicine coupled with nanotherapeutics may allow fulfillment of those gaps, together with screening of novel therapeutic drugs and target delivery systems. PMID:25328416

Roma-Rodrigues, Catarina; Fernandes, Alexandra R

2014-01-01

256

Molecular Rayleigh Scattering Techniques Developed for Measuring Gas Flow Velocity, Density, Temperature, and Turbulence  

NASA Technical Reports Server (NTRS)

Nonintrusive optical point-wise measurement techniques utilizing the principles of molecular Rayleigh scattering have been developed at the NASA Glenn Research Center to obtain time-averaged information about gas velocity, density, temperature, and turbulence, or dynamic information about gas velocity and density in unseeded flows. These techniques enable measurements that are necessary for validating computational fluid dynamics (CFD) and computational aeroacoustic (CAA) codes. Dynamic measurements allow the calculation of power spectra for the various flow properties. This type of information is currently being used in jet noise studies, correlating sound pressure fluctuations with velocity and density fluctuations to determine noise sources in jets. These nonintrusive techniques are particularly useful in supersonic flows, where seeding the flow with particles is not an option, and where the environment is too harsh for hot-wire measurements.

Mielke, Amy F.; Seasholtz, Richard G.; Elam, Kristie A.; Panda, Jayanta

2005-01-01

257

Advances in laparoscopic techniques in pelvic reconstructive surgery for prolapse and incontinence.  

PubMed

Advances in minimally invasive surgery have led to an increasing adoption of laparoscopic techniques in pelvic reconstructive surgery and treatment of urinary incontinence. Our review of recent developments aims to identify and evaluate the evidence for use of these procedures. Recent literature continues to support the use of laparoscopy for colposuspension and sacrocolpopexy, as an effective alternative to open surgery. However, with the advent of retropubic mid-urethral slings for stress urinary incontinence, laparoscopic Burch colposuspension has now become obsolete. There are relatively few reports on other laparoscopic prolapse procedures, such as uterosacral ligament vault suspension, uterine suspension, paravaginal defect repair and rectocele repair. In conclusion, several short-term studies support the use of laparoscopy in pelvic reconstructive surgery and urogynaecology but longer-term investigations are needed to confirm their findings. PMID:19231115

Price, Natalia; Jackson, Simon R

2009-03-20

258

Advanced burden level measurement radars using FFT signal processing techniques. [Fast Fourier Transform  

SciTech Connect

Advanced design level-measuring radars have been developed and installed at Bethlehem Steel's Burns Harbor Plant to measure burden height in operating blast furnaces. Modern signal processing techniques are used in conjunction with a self-calibrating wideband swept-frequency dual-antenna radar to enhance measurement accuracy and better differentiate true surface returns from extraneous reflections. Provisions have been included to monitor and record critical parameters of the radar and various installation accessories to improve maintainability and instrumentation accuracy. A ruggedized personal computer is used to perform the signal processing calculations, determine the distance in terms related to the furnace dimensions, sequence the remote monitoring elements, provide graphic displays of the real-time and historic burden height and monitor data, and operate the complete system from a basic keyboard.

Mawhinney, D.D. (MMTC, Inc., Princeton, NJ (United States)); Presser, A. (MMTC, Inc., Princeton, NJ (United States)); Koselke, T.G. (Bethlehem Steel Corp., Chesterton, IN (United States))

1993-01-01

259

A multiscale modeling technique for bridging molecular dynamics with finite element method  

SciTech Connect

In computational mechanics, molecular dynamics (MD) and finite element (FE) analysis are well developed and most popular on nanoscale and macroscale analysis, respectively. MD can very well simulate the atomistic behavior, but cannot simulate macroscale length and time due to computational limits. FE can very well simulate continuum mechanics (CM) problems, but has the limitation of the lack of atomistic level degrees of freedom. Multiscale modeling is an expedient methodology with a potential to connect different levels of modeling such as quantum mechanics, molecular dynamics, and continuum mechanics. This study proposes a new multiscale modeling technique to couple MD with FE. The proposed method relies on weighted average momentum principle. A wave propagation example has been used to illustrate the challenges in coupling MD with FE and to verify the proposed technique. Furthermore, 2-Dimensional problem has also been used to demonstrate how this method would translate into real world applications. -- Highlights: •A weighted averaging momentum method is introduced for bridging molecular dynamics (MD) with finite element (FE) method. •The proposed method shows excellent coupling results in 1-D and 2-D examples. •The proposed method successfully reduces the spurious wave reflection at the border of MD and FE regions. •Big advantages of the proposed method are simplicity and inexpensive computational cost of multiscale analysis.

Lee, Yongchang, E-mail: yl83@buffalo.edu; Basaran, Cemal

2013-11-15

260

Theory of the double-edge molecular technique for Doppler lidar wind measurement.  

PubMed

The theory of the double-edge lidar technique for measuring the wind with molecular backscatter is described. Two high-spectral-resolution edge filters are located in the wings of the Rayleigh-Brillouin profile. This doubles the signal change per unit Doppler shift, the sensitivity, and improves measurement accuracy relative to the single-edge technique by nearly a factor of 2. The use of a crossover region where the sensitivity of a molecular- and an aerosol-based measurement is equal is described. Use of this region desensitizes the molecular measurement to the effects of aerosol scattering over a velocity range of +/-100 m/s. We give methods for correcting short-term, shot-to-shot, frequency jitter and drift with a laser reference frequency measurement and methods for long-term frequency correction with a servo control system. The effects of Rayleigh-Brillouin scattering on the measurement are shown to be significant and are included in the analysis. Simulations for a conical scanning satellite-based lidar at 355 nm show an accuracy of 2-3 m/s for altitudes of 2-15 km for a 1-km vertical resolution, a satellite altitude of 400 km, and a 200 km x 200 km spatial resolution. PMID:18305631

Flesia, C; Korb, C L

1999-01-20

261

A fast data reduction algorithm for molecular tagging velocimetry: the decoupled spatial correlation technique  

NASA Astrophysics Data System (ADS)

Molecular tagging velocimetry (MTV) involves intensive data reduction that extracts flow velocity information from the Lagrangian tracking of phosphorescing fluid material. A computationally efficient algorithm for the data reduction is thus of practical interest for processing large MTV data sets. We were motivated by this consideration into developing a simplified version of the spatial correlation technique, the decoupled spatial correlation technique, in an effort to seek a balance between accuracy and efficiency. By Taylor series analysis it is shown that, if the Lagrangian displacement vector can be roughly pre-determined, the two components in the displacement vectors that have to be solved simultaneously using the spatial correlation technique can now be determined independently in two orthogonal directions. This decoupling results in about an order of magnitude decrease in the CPU time required. An accuracy estimate based on artificial images that follow the motion of a line vortex indicates that the technique can determine displacements to within 0.08 pixel. This technique was also used to process MTV images acquired in a cross stream plane of the transverse jet. This flow is characterized by a large scale counter-rotating vortex pair (CVP). The velocity fields obtained clearly show the existence of this CVP, which provides further verification of this technique.

Zheng, Qingxiong; Klewicki, Joseph C.

2000-09-01

262

PREFACE: 14th International Workshop on Advanced Computing and Analysis Techniques in Physics Research (ACAT 2011)  

NASA Astrophysics Data System (ADS)

ACAT2011 This volume of Journal of Physics: Conference Series is dedicated to scientific contributions presented at the 14th International Workshop on Advanced Computing and Analysis Techniques in Physics Research (ACAT 2011) which took place on 5-7 September 2011 at Brunel University, UK. The workshop series, which began in 1990 in Lyon, France, brings together computer science researchers and practitioners, and researchers from particle physics and related fields in order to explore and confront the boundaries of computing and of automatic data analysis and theoretical calculation techniques. It is a forum for the exchange of ideas among the fields, exploring and promoting cutting-edge computing, data analysis and theoretical calculation techniques in fundamental physics research. This year's edition of the workshop brought together over 100 participants from all over the world. 14 invited speakers presented key topics on computing ecosystems, cloud computing, multivariate data analysis, symbolic and automatic theoretical calculations as well as computing and data analysis challenges in astrophysics, bioinformatics and musicology. Over 80 other talks and posters presented state-of-the art developments in the areas of the workshop's three tracks: Computing Technologies, Data Analysis Algorithms and Tools, and Computational Techniques in Theoretical Physics. Panel and round table discussions on data management and multivariate data analysis uncovered new ideas and collaboration opportunities in the respective areas. This edition of ACAT was generously sponsored by the Science and Technology Facility Council (STFC), the Institute for Particle Physics Phenomenology (IPPP) at Durham University, Brookhaven National Laboratory in the USA and Dell. We would like to thank all the participants of the workshop for the high level of their scientific contributions and for the enthusiastic participation in all its activities which were, ultimately, the key factors in the success of the workshop. Further information on ACAT 2011 can be found at http://acat2011.cern.ch Dr Liliana Teodorescu Brunel University ACATgroup The PDF also contains details of the workshop's committees and sponsors.

Teodorescu, Liliana; Britton, David; Glover, Nigel; Heinrich, Gudrun; Lauret, Jérôme; Naumann, Axel; Speer, Thomas; Teixeira-Dias, Pedro

2012-06-01

263

Mass spectrometric techniques for characterizing low-molecular-weight resins used as paint varnishes.  

PubMed

The molecular structure of three low-molecular-weight resins used as paint varnishes has been characterized by use of an approach based on three different mass spectrometric techniques. We investigated the ketone resin MS2A, the aldehyde resin Laropal A81, and the hydrocarbon resin Regalrez 1094, now commonly used in restoration. To date, the molecular structures of these resins have not been completely elucidated. To improve current knowledge of the chemical composition of these materials, information obtained by gas chromatography-mass spectrometry (GC/MS), pyrolysis-gas chromatography-mass spectrometry (Py/GC/MS), and electrospray ionization mass spectrometry (ESI-Q-ToF) was combined. Analysis, in solution, of the whole polymeric fraction of the resins by flow-injection ESI-Q-ToF, and of the non-polymeric fraction by GC-MS, enabled us to identify previously unreported features of the polymer structures. In addition, the Py-GC/MS profiles that we obtained will help to enhance the databases currently available in the literature. The proposed approach can be extended to other low-molecular-weight resins used as varnishes in conservation. PMID:23151653

Bonaduce, I; Colombini, M P; Degano, I; Di Girolamo, F; La Nasa, J; Modugno, F; Orsini, S

2013-01-01

264

Molecular-Based Optical Measurement Techniques for Transition and Turbulence in High-Speed Flow  

NASA Technical Reports Server (NTRS)

High-speed laminar-to-turbulent transition and turbulence affect the control of flight vehicles, the heat transfer rate to a flight vehicle's surface, the material selected to protect such vehicles from high heating loads, the ultimate weight of a flight vehicle due to the presence of thermal protection systems, the efficiency of fuel-air mixing processes in high-speed combustion applications, etc. Gaining a fundamental understanding of the physical mechanisms involved in the transition process will lead to the development of predictive capabilities that can identify transition location and its impact on parameters like surface heating. Currently, there is no general theory that can completely describe the transition-to-turbulence process. However, transition research has led to the identification of the predominant pathways by which this process occurs. For a truly physics-based model of transition to be developed, the individual stages in the paths leading to the onset of fully turbulent flow must be well understood. This requires that each pathway be computationally modeled and experimentally characterized and validated. This may also lead to the discovery of new physical pathways. This document is intended to describe molecular based measurement techniques that have been developed, addressing the needs of the high-speed transition-to-turbulence and high-speed turbulence research fields. In particular, we focus on techniques that have either been used to study high speed transition and turbulence or techniques that show promise for studying these flows. This review is not exhaustive. In addition to the probe-based techniques described in the previous paragraph, several other classes of measurement techniques that are, or could be, used to study high speed transition and turbulence are excluded from this manuscript. For example, surface measurement techniques such as pressure and temperature paint, phosphor thermography, skin friction measurements and photogrammetry (for model attitude and deformation measurement) are excluded to limit the scope of this report. Other physical probes such as heat flux gauges, total temperature probes are also excluded. We further exclude measurement techniques that require particle seeding though particle based methods may still be useful in many high speed flow applications. This manuscript details some of the more widely used molecular-based measurement techniques for studying transition and turbulence: laser-induced fluorescence (LIF), Rayleigh and Raman Scattering and coherent anti-Stokes Raman scattering (CARS). These techniques are emphasized, in part, because of the prior experience of the authors. Additional molecular based techniques are described, albeit in less detail. Where possible, an effort is made to compare the relative advantages and disadvantages of the various measurement techniques, although these comparisons can be subjective views of the authors. Finally, the manuscript concludes by evaluating the different measurement techniques in view of the precision requirements described in this chapter. Additional requirements and considerations are discussed to assist with choosing an optical measurement technique for a given application.

Bathel, Brett F.; Danehy, Paul M.; Cutler, Andrew D.

2013-01-01

265

Advancements in sensing and perception using structured lighting techniques :an LDRD final report.  

SciTech Connect

This report summarizes the analytical and experimental efforts for the Laboratory Directed Research and Development (LDRD) project entitled ''Advancements in Sensing and Perception using Structured Lighting Techniques''. There is an ever-increasing need for robust, autonomous ground vehicles for counterterrorism and defense missions. Although there has been nearly 30 years of government-sponsored research, it is undisputed that significant advancements in sensing and perception are necessary. We developed an innovative, advanced sensing technology for national security missions serving the Department of Energy, the Department of Defense, and other government agencies. The principal goal of this project was to develop an eye-safe, robust, low-cost, lightweight, 3D structured lighting sensor for use in broad daylight outdoor applications. The market for this technology is wide open due to the unavailability of such a sensor. Currently available laser scanners are slow, bulky and heavy, expensive, fragile, short-range, sensitive to vibration (highly problematic for moving platforms), and unreliable for outdoor use in bright sunlight conditions. Eye-safety issues are a primary concern for currently available laser-based sensors. Passive, stereo-imaging sensors are available for 3D sensing but suffer from several limitations : computationally intensive, require a lighted environment (natural or man-made light source), and don't work for many scenes or regions lacking texture or with ambiguous texture. Our approach leveraged from the advanced capabilities of modern CCD camera technology and Center 6600's expertise in 3D world modeling, mapping, and analysis, using structured lighting. We have a diverse customer base for indoor mapping applications and this research extends our current technology's lifecycle and opens a new market base for outdoor 3D mapping. Applications include precision mapping, autonomous navigation, dexterous manipulation, surveillance and reconnaissance, part inspection, geometric modeling, laser-based 3D volumetric imaging, simultaneous localization and mapping (SLAM), aiding first responders, and supporting soldiers with helmet-mounted LADAR for 3D mapping in urban-environment scenarios. The technology developed in this LDRD overcomes the limitations of current laser-based 3D sensors and contributes to the realization of intelligent machine systems reducing manpower need.

Novick, David Keith; Padilla, Denise D.; Davidson, Patrick A. Jr. (.; .); Carlson, Jeffrey J.

2005-09-01

266

Using DRIFT molecular spectroscopy with uni- and multivariate spectral techniques to detect protein molecular structure differences among different genotypes of barley.  

PubMed

The objectives of this study were to characterize protein molecular structure using DRIFT spectroscopy with univariate and multivariate molecular spectral analyses and identify the structure differences in both hull and seeds among six spring barley varieties [AC Metcalfe (malting-type), CDC Dolly (feed-type, spring forage type), McLeod (feed-type), CDC Helgason (feed-type), CDC Trey (feed-type), CDC Cowboy (feed-type)]. The molecular structure spectral analyses involved protein amide I and II region ca. 1716-1485 cm(-1) (attributed to protein amide I C=O and C-N stretching; amide II N-H bending and C-N stretching) together with agglomerative hierarchical cluster (CLA) and principal component analyses (PCA). The results showed that the molecular spectral techniques were able to identify spectral differences associated with the molecular structural differences among the barley varieties. The molecular spectral analyses at the region of ca. 1715-1485 cm(-1) together with the cluster and principal component analyses were able to show that the molecular structures of the seeds (NOT hull) exhibited distinguished differences among the barley varieties. It was found that CDC Helgason had the distinguished differences from AC Metcalfe, McLeod, and CDC Cowboy in both protein amide I and II. The molecular spectral technique provides a new approach for plant protein molecular structure and biopolymer conformation study. PMID:20441231

Liu, Na; Yu, Peiqiang

2010-05-26

267

Recent advances on techniques and theories of feedforward networks with supervised learning  

NASA Astrophysics Data System (ADS)

The rediscovery and popularization of the back propagation training technique for multilayer perceptrons as well as the invention of the Boltzmann Machine learning algorithm has given a new boost to the study of supervised learning networks. In recent years, besides the widely spread applications and the various further improvements of the classical back propagation technique, many new supervised learning models, techniques as well as theories, have also been proposed in a vast number of publications. This paper tries to give a rather systematical review on the recent advances on supervised learning techniques and theories for static feedforward networks. We summarize a great number of developments into four aspects: (1) Various improvements and variants made on the classical back propagation techniques for multilayer (static) perceptron nets, for speeding up training, avoiding local minima, increasing the generalization ability, as well as for many other interesting purposes. (2) A number of other learning methods for training multilayer (static) perceptron, such as derivative estimation by perturbation, direct weight update by perturbation, genetic algorithms, recursive least square estimate and extended Kalman filter, linear programming, the policy of fixing one layer while updating another, constructing networks by converting decision tree classifiers, and others. (3) Various other feedforward models which are also able to implement function approximation, probability density estimation and classification, including various models of basis function expansion (e.g., radial basis functions, restricted coulomb energy, multivariate adaptive regression splines, trigonometric and polynomial bases, projection pursuit, basis function tree, and may others), and several other supervised learning models. (4) Models with complex structures, e.g., modular architecture, hierarchy architecture, and others. (5) A number of theoretical issues involving the universal approximation of continuous functions, best approximation ability, learnability, capability, generalization ability, and the relations between these abilities to the number of layers in a network, the number of the neurons needed, hidden neurons, as well as the number of training samples. Altogether, we try to give a global picture of the present state of supervised learning techniques and theories for training static feedforward networks.

Xu, Lei; Klasa, Stan

1992-07-01

268

Advanced Molecular Profiling in Vivo Detects Novel Function of Dickkopf-3 in the Regulation of Bone Formation  

E-print Network

development(1) and fracture healing.(2) Endochondral bone formation is a multistep process that involves to verify and understand the complexity of endochondral bone forma- tion. In a rat fracture model, severalAdvanced Molecular Profiling in Vivo Detects Novel Function of Dickkopf-3 in the Regulation of Bone

Domany, Eytan

269

Studies of signaling domains in model and biological membranes through advanced imaging techniques: final report.  

SciTech Connect

Cellular membranes have complex lipid and protein structures that are laterally organized for optimized molecular recognition and signal transduction processes. Knowledge of nanometer-scale lateral organization and its function is of great importance in the analysis of receptor-based signaling. In model membranes, we studied in detail the chemical and physical factors which result in lateral organization of lipids and lipid-mediated protein sequestration into signaling domains. In biological membranes, we mapped the location and follow the dynamic activity of specific membrane proteins involved in the immunological response of mast cells. These studies were enabled by our development of advanced imaging methods that provided both high spatial resolution and sensitivity to dynamical processes. Our technical approach was to combine the high sensitivity and time resolution of fluorescence imaging with the high lateral resolution of atomic force microscopy (AFM). Simultaneous fluorescence and AFM imaging allows correlation of the distribution and dynamic activity of specific biomolecules via fluorescence labeling with complete topographic information of the membrane. Overall, our unique imaging capabilities enabled us to examine membrane structure and function with much greater detail than was previously possible and thus provide a better understanding of cellular signaling.

Oliver, Janet (University of New Mexico School of Medicine, Albuquerque, NM); Pfeiffer, Janet (New Mexico School of Medicine, Albuquerque, NM); Wilson, Bridget (University of New Mexico School of Medicine, Albuquerque, NM); Burns, Alan Richard

2006-10-01

270

Recoil separators for radiative capture using radioactive ion beams. Recent advances and detection techniques  

NASA Astrophysics Data System (ADS)

Radiative capture reactions involving the fusion of hydrogen or helium are ubiquitous in the stellar history of the universe, and are some of the most important reactions in the processes that govern nucleosynthesis and energy generation in both static and explosive scenarios. However, radiative capture reactions pose some of the most difficult experimental challenges due to extremely small cross sections. With the advent of recoil separators and techniques in inverse kinematics, it is now possible to measure radiative capture reactions on very short-lived radioactive nuclei, and in the presence of high experimental backgrounds. In this paper we review the experimental needs for making measurements of astrophysical importance on radiative capture reactions. We also review some of the important historical advances in the field of recoil separators as well as describe current techniques and performance milestones, including descriptions of some of the separators most recently working at radioactive ion beam facilities, such as DRAGON at TRIUMF and the DRS at the Holifield Radioactive Ion Beam Facility. We will also summarize some of the scientific highlight measurements at the RIB facilities.

Ruiz, Chris; Greife, Uwe; Hager, Ulrike

2014-06-01

271

Nanostructural defects evidenced in failing silicon-based NMOS capacitors by advanced failure analysis techniques  

NASA Astrophysics Data System (ADS)

An experimental methodology compliant with industrial constraints was deployed to uncover the origin of soft breakdown events in large planar silicon-based NMOS capacitors. Complementary advanced failure analysis techniques were advantageously employed to localize, isolate and observe structural defects at nanoscale. After an accurate localization of the failing area by optical beam-induced resistance change (OBIRCH), focused ion beam (FIB) technique enabled preparing thin specimens adequate for transmission electron microscopy (TEM). Characterization of the gate oxide microstructure was performed by highresolution TEM imaging and energy-filtered spectroscopy. A dedicated experimental protocol relying on iterative FIB thinning and TEM observation enabled improving the quality of electron imaging of defects at atom scale. In that way, the gate oxide integrity was evaluated and an electrical stress-induced silicon epitaxy was detected concomitantly to soft breakdown events appearing during constant voltage stress. The growth of silicon hillocks enables consuming a part of the breakdown energy and may prevent the soft breakdown event to evolve towards a hard breakdown that is catastrophic for device functionality.

Faivre, Emilie; Llido, Roxane; Putero, Magali; Fares, Lahouari; Muller, Christophe

2014-04-01

272

Investigation to advance prediction techniques of the low-speed aerodynamics of V/STOL aircraft  

NASA Technical Reports Server (NTRS)

A computer program, VSAERO, has been applied to a number of V/STOL configurations with a view to advancing prediction techniques for the low-speed aerodynamic characteristics. The program couples a low-order panel method with surface streamline calculation and integral boundary layer procedures. The panel method--which uses piecewise constant source and doublet panels-includes an iterative procedure for wake shape and models boundary layer displacement effect using the source transpiration technique. Certain improvements to a basic vortex tube jet model were installed in the code prior to evaluation. Very promising results were obtained for surface pressures near a jet issuing at 90 deg from a flat plate. A solid core model was used in the initial part of the jet with a simple entrainment model. Preliminary representation of the downstream separation zone significantly improve the correlation. The program accurately predicted the pressure distribution inside the inlet on the Grumman 698-411 design at a range of flight conditions. Furthermore, coupled viscous/potential flow calculations gave very close correlation with experimentally determined operational boundaries dictated by the onset of separation inside the inlet. Experimentally observed degradation of these operational boundaries between nacelle-alone tests and tests on the full configuration were also indicated by the calculation. Application of the program to the General Dynamics STOL fighter design were equally encouraging. Very close agreement was observed between experiment and calculation for the effects of power on pressure distribution, lift and lift curve slope.

Maskew, B.; Strash, D.; Nathman, J.; Dvorak, F. A.

1985-01-01

273

Advances in conservation endocrinology: the application of molecular approaches to the conservation of endangered species.  

PubMed

Among the numerous societal benefits of comparative endocrinology is the application of our collective knowledge of hormone signaling towards the conservation of threatened and endangered species - conservation endocrinology. For several decades endocrinologists have used longitudinal hormone profiles to monitor reproductive status in a multitude of species. Knowledge of reproductive status among individuals has been used to assist in the management of captive and free-ranging populations. More recently, researchers have begun utilizing molecular and cell-based techniques to gain a more complete understanding of hormone signaling in wildlife species, and to identify potential causes of disrupted hormone signaling. In this review we examine various in vitro approaches we have used to compare estrogen receptor binding and activation by endogenous hormones and phytoestrogens in two species of rhinoceros; southern white and greater one-horned. We have found many of these techniques valuable and practical in species where access to research subjects and/or tissues is limited due to their conservation status. From cell-free, competitive binding assays to full-length receptor activation assays; each technique has strengths and weaknesses related to cost, sensitivity, complexity of the protocols, and relevance to in vivo signaling. We then present a novel approach, in which receptor activation assays are performed in primary cell lines derived from the species of interest, to minimize the artifacts of traditional heterologous expression systems. Finally, we speculate on the promise of next generation sequencing and transcriptome profiling as tools for characterizing hormone signaling in threatened and endangered species. PMID:24613137

Tubbs, Christopher; McDonough, Caitlin E; Felton, Rachel; Milnes, Matthew R

2014-07-01

274

Study of DNA interactions with bifenthrin by spectroscopic techniques and molecular modeling  

NASA Astrophysics Data System (ADS)

The interaction between bifenthrin (BF) and calf thymus DNA (ctDNA) in physiological buffer (pH 7.4) was investigated by UV-vis absorption, fluorescence, circular dichroism (CD), and Fourier transform infrared (FT-IR) spectroscopy, coupled with viscosity measurements and molecular docking techniques. It was found that BF molecular could intercalate into the base pairs of ctDNA as evidenced by significant increases in absorption intensity, fluorescence polarization and relative viscosity of ctDNA, decrease in iodide quenching effect, and induced CD spectral changes. The association constant of BF with ctDNA was evaluated to be in the order of 104 L mol-1. Thermodynamic analysis of the binding data obtained at different temperatures suggested that the binding process was primarily driven by hydrogen bonds and van der Waals forces, as the values of the enthalpy change (?H) and the entropy change (?S) were calculated to be -31.13 ± 1.89 kJ mol-1 and -22.79 ± 1.21 J mol-1 K-1, respectively. The results of FT-IR spectra and molecular docking showed that a specific binding mainly existed between BF and adenine and guanine bases.

Zhu, Pan; Zhang, Guowen; Ma, Yadi; Zhang, Yepeng; Miao, Hong; Wu, Yongning

2013-08-01

275

Molecular Advances Leading to Treatment Implications for Fragile X Premutation Carriers  

PubMed Central

Fragile X syndrome (FXS) is the most common single gene cause of intellectual disability and it is characterized by a CGG expansion of more than 200 repeats in the FMR1 gene, leading to methylation of the promoter and gene silencing. The fragile X premutation, characterized by a 55 to 200 CGG repeat expansion, causes health problems and developmental difficulties in some, but not all, carriers. The premutation causes primary ovarian insufficiency in approximately 20% of females, psychiatric problems (including depression and/or anxiety) in approximately 50% of carriers and a neurodegenerative disorder, the fragile X-associated tremor ataxia syndrome (FXTAS), in approximately 40% of males and 16% of females later in life. Recent clinical studies in premutation carriers have expanded the health problems that may be seen. Advances in the molecular pathogenesis of the premutation have shown significant mitochondrial dysfunction and oxidative stress in neurons which may be amenable to treatment. Here we review the clinical problems of carriers and treatment recommendations.

Polussa, Jonathan; Schneider, Andrea; Hagerman, Randi

2014-01-01

276

Advanced evolutionary molecular engineering to produce thermostable cellulase by using a small but efficient library.  

PubMed

We aimed at constructing thermostable cellulase variants of cellobiohydrolase II, derived from the mesophilic fungus Phanerochaete chrysosporium, by using an advanced evolutionary molecular engineering method. By aligning the amino acid sequences of the catalytic domains of five thermophilic fungal CBH2 and PcCBH2 proteins, we identified 45 positions where the PcCBH2 genes differ from the consensus sequence of two to five thermophilic fungal CBH2s. PcCBH2 variants with the consensus mutations were obtained by a cell-free translation system that was chosen for easy evaluation of thermostability. From the small library of consensus mutations, advantageous mutations for improving thermostability were found to occur with much higher frequency relative to a random library. To further improve thermostability, advantageous mutations were accumulated within the wild-type gene. Finally, we obtained the most thermostable variant Mall4, which contained all 15 advantageous mutations found in this study. This variant had the same specific cellulase activity as the wild type and retained sufficient activity at 50°C for >72 h, whereas wild-type PcCBH2 retained much less activity under the same conditions. The history of the accumulation process indicated that evolution of PcCBH2 toward improved thermostability was ideally and rapidly accomplished through the evolutionary process employed in this study. PMID:23091162

Ito, Y; Ikeuchi, A; Imamura, C

2013-01-01

277

Oculopharyngeal muscular dystrophy: recent advances in the understanding of the molecular pathogenic mechanisms and treatment strategies.  

PubMed

Oculopharyngeal muscular dystrophy (OPMD) is an adult-onset disorder characterized by progressive eyelid drooping, swallowing difficulties and proximal limb weakness. OPMD is caused by a small expansion of a short polyalanine tract in the poly (A) binding protein nuclear 1 protein (PABPN1). The mechanism by which the polyalanine expansion mutation in PABPN1 causes disease is unclear. PABPN1 is a nuclear multi-functional protein which is involved in pre-mRNA polyadenylation, transcription regulation, and mRNA nucleocytoplasmic transport. The distinct pathological hallmark of OPMD is the presence of filamentous intranuclear inclusions (INIs) in patient's skeletal muscle cells. The exact relationship between mutant PABPN1 intranuclear aggregates and pathology is not clear. OPMD is a unique disease sharing common pathogenic features with other polyalanine disorders, as well as with polyglutamine and dystrophic disorders. This chapter aims to review the rapidly growing body of knowledge concerning OPMD. First, we outline the background of OPMD. Second, we compare OPMD with other trinucleotide repeat disorders. Third, we discuss the recent advances in the understanding of the molecular mechanisms underlying OPMD pathogenesis. Finally, we review recent therapeutic strategies for OPMD. PMID:17110089

Abu-Baker, Aida; Rouleau, Guy A

2007-02-01

278

Removal of effluent dissolved organic matter of different molecular sizes by advanced treatments and soil infiltration.  

PubMed

Removal of municipal effluent-derived dissolved organic matter (DOM) of various apparent molecular weights (AMWs) was compared among ozonation, nanofiltration, ultrafiltration, and magnetic ion exchange (MIEX) resin coagulation. These advanced technologies were applied as pretreatments for soil aquifer treatment (SAT). Soil aquifer treatment alone removed 20 to 30% of dissolved organic carbon (DOC) and UV254. Soil aquifer treatment effectively removed 100% and 76% of DOM with AMWs of 21.3 to 31.6 kDa and 0.4 to 1.0 kDa, respectively. With pretreatments of ozonation, MIEX resin coagulation and nanofiltration, substantially higher removals (40 to 75%) were achieved for DOC and UV254. The removal efficiency of the entire system decreased as nanofiltration-SAT > ozonation-SAT > MIEX-SAT > ultrafiltration-SAT, which is positively related to the removal efficiency for medium AMW (1.8 to 7.7 kDa, mainly humic substances) DOM during pretreatments. Different pretreatments should, therefore, be chosen in accordance with the water quality of feed water and water products and SAT removal efficiency. PMID:24617114

Zhang, Xue; Zhao, Xuan; Gao, Yutuan; Zhang, Meng

2014-01-01

279

Evaluation of genetically modified sugarcane lines carrying Cry 1AC gene using molecular marker techniques.  

PubMed

Five genetically modified insect resistant sugarcane lines harboring the Bt Cry 1AC gene to produce insecticidal proteins were compared with non-transgenic control by using three types of molecular marker techniques namely, RAPD, ISSR and AFLP. These techniques were applied on transgenic and non-transgenic plants to investigate the genetic variations, which may appear in sugarcane clones. This variation might demonstrate the genomic changes associated with the transformation process, which could change important molecular basis of various biological phenomena. Genetic variations were screened using 22 different RAPD primers, 10 ISSR primers and 13 AFLP primer combinations. Analysis of RAPD and ISSR banding patterns gave no exclusive evidence for genetic variations. Meanwhile, the percentage of polymorphic bands was 0.45% in each of RAPD and ISSR, while the polymorphism generated by AFLP analysis was 1.8%. The maximum percentage of polymorphic bands was 1.4%, 1.1% and 5.5% in RAPD, ISSR and AFLP, respectively. These results demonstrate that most transgenic lines showed genomic homogeneity and verified minor genomic changes. Dendrograms revealing the relationships among the transgenic and control plants were developed from the data of each of the three marker types. PMID:23549345

Ismail, Roba M

2013-01-01

280

An effusive molecular beam technique for studies of polyatomic gas-surface reactivity and energy transfer  

NASA Astrophysics Data System (ADS)

An effusive molecular beam technique is described to measure alkane dissociative sticking coefficients, S(Tg, Ts; ?), on metal surfaces for which the impinging gas temperature, Tg, and surface temperature, Ts, can be independently varied, along with the angle of incidence, ?, of the impinging gas. Effusive beam experiments with Tg = Ts = T allow for determination of angle-resolved dissociative sticking coefficients, S(T; ?), which when averaged over the cos (?)/? angular distribution appropriate to the impinging flux from a thermal ambient gas yield the thermal dissociative sticking coefficient, S(T). Nonequilibrium S(Tg, Ts; ?) measurements for which Tg ? Ts provide additional opportunities to characterize the transition state and gas-surface energy transfer at reactive energies. A resistively heated effusive molecular beam doser controls the Tg of the impinging gas striking the surface. The flux of molecules striking the surface from the effusive beam is determined from knowledge of the dosing geometry, chamber pressure, and pumping speed. Separate experiments with a calibrated leak serve to fix the chamber pumping speed. Postdosing Auger electron spectroscopy is used to measure the carbon of the alkyl radical reaction product that is deposited on the surface as a result of alkane dissociative sticking. As implemented in a typical ultrahigh vacuum chamber for surface analysis, the technique has provided access to a dynamic range of roughly 6 orders of magnitude in the initial dissociative sticking coefficient for small alkanes on Pt(111).

Cushing, G. W.; Navin, J. K.; Valadez, L.; Johánek, V.; Harrison, I.

2011-04-01

281

An Intensive Hands-on Course Designed to Teach Molecular Biology Techniques to Physiology Graduate Students  

NSDL National Science Digital Library

To address a growing need to make research trainees in physiology comfortable with the tools of molecular biology, we have developed a laboratory-intensive course designed for graduate students. This course is offered to a small group of students over a three-week period and is organized such that comprehensive background lectures are coupled with extensive hands-on experience. The course is divided into seven modules, each organized by a faculty member who has particular expertise in the area covered by that module. The modules focus on basic methods such as cDNA subcloning, sequencing, gene transfer, polymerase chain reaction, and protein and RNA expression analysis. Each module begins with a lecture that introduces the technique in detail by providing a historical perspective, describing both the uses and limitations of that technique, and comparing the method with others that yield similar information. Most of the lectures are followed by a laboratory session during which students follow protocols that were carefully designed to avoid pitfalls. Throughout these laboratory sessions, students are given an appreciation of the importance of proper technique and accuracy. Communication among the students, faculty, and the assistant coordinator is focused on when and why each procedure would be used, the importance of each step in the procedure, and approaches to troubleshooting. The course ends with an exam that is designed to test the studentsÃÂ general understanding of each module and their ability to apply the various techniques to physiological questions.

Dr. Andrea D. Weston (University of Western Ontario Department of Physiology); Dr. Sasha Stasko (University of Western Ontario Department of Physiology); PhD Gerald M. Kidder (Univ. of Western Ontario Dept. of Physiology)

2002-03-01

282

75 FR 81643 - In the Matter of Certain Semiconductor Products Made by Advanced Lithography Techniques and...  

Federal Register 2010, 2011, 2012, 2013

...337-TA-729] In the Matter of Certain Semiconductor Products Made by Advanced Lithography...States after importation of certain semiconductor products made by advanced lithography...complaint named two respondents: Taiwan Semiconductor Manufacturing, Co., Ltd....

2010-12-28

283

Application of different molecular techniques for characterization of catalase-positive cocci isolated from sucuk.  

PubMed

This study was carried out for the characterization and discrimination of the indigenous Gram positive, catalase-positive cocci (GCC) population in sucuk, a traditional Turkish dry-fermented sausage. Sucuk samples, produced by the traditional method without starter culture were collected from 8 local producers in Kayseri/Turkey and a total of 116 GCC isolates were identified by using different molecular techniques. Two different molecular fingerprinting methods; namely, randomly amplified polymorphic DNA-PCR (RAPD-PCR) and repetitive extragenic palindrome-PCR (rep-PCR), were used for the clustering of isolates and identification at species level was carried out by full length sequencing of 16S rDNA. Combining the results obtained from molecular fingerprinting and 16S rDNA sequencing showed that the dominant GCC species isolated from the sucuk samples was Staphylococcus saprophyticus followed by Staphylococcus succinus and Staphylococcus equorum belonging to the Staphylococcus genus. Real-time PCR DNA melting curve analysis and high-resolution melting (HRM) analysis targeting the V1 + V3 regions of 16S rDNA were also applied for the discrimination of isolates belonging to different species. It was observed statistically different Tm values and species-specific HRM profiles for all except 2 species (S. saprophyticus and Staphylococcus xylosus) that have high 16S rDNA sequence similarity. The combination of rep-PCR and/or PCR-RAPD with 16S rRNA gene sequencing was an efficient approach for the characterization and identification of the GCC population in spontaneously fermented sucuk. On the other hand, intercalating dye assays were found to be a simple and very promising technique for the differentiation of the GCC population at species level. PMID:24410408

Kesmen, Zülal; Yarimcam, Burcu; Aslan, Hakiye; Ozbekar, Esra; Yetim, Hasan

2014-02-01

284

Experimental investigations of micro-scale flow and heat transfer phenomena by using molecular tagging techniques  

NASA Astrophysics Data System (ADS)

Recent progress made in the development of novel molecule-based flow diagnostic techniques, including molecular tagging velocimetry (MTV) and lifetime-based molecular tagging thermometry (MTT), to achieve simultaneous measurements of multiple important flow variables for micro-flows and micro-scale heat transfer studies is reported in this study. The focus of the work described here is the particular class of molecular tagging tracers that relies on phosphorescence. Instead of using tiny particles, especially designed phosphorescent molecules, which can be turned into long-lasting glowing marks upon excitation by photons of appropriate wavelength, are used as tracers for both flow velocity and temperature measurements. A pulsed laser is used to 'tag' the tracer molecules in the regions of interest, and the tagged molecules are imaged at two successive times within the photoluminescence lifetime of the tracer molecules. The measured Lagrangian displacement of the tagged molecules provides the estimate of the fluid velocity. The simultaneous temperature measurement is achieved by taking advantage of the temperature dependence of phosphorescence lifetime, which is estimated from the intensity ratio of the tagged molecules in the acquired two phosphorescence images. The implementation and application of the molecular tagging approach for micro-scale thermal flow studies are demonstrated by two examples. The first example is to conduct simultaneous flow velocity and temperature measurements inside a microchannel to quantify the transient behavior of electroosmotic flow (EOF) to elucidate underlying physics associated with the effects of Joule heating on electrokinematically driven flows. The second example is to examine the time evolution of the unsteady heat transfer and phase changing process inside micro-sized, icing water droplets, which is pertinent to the ice formation and accretion processes as water droplets impinge onto cold wind turbine blades.

Hu, Hui; Jin, Zheyan; Nocera, Daniel; Lum, Chee; Koochesfahani, Manoochehr

2010-08-01

285

Application of Energy Integration Techniques to the Design of Advanced Life Support Systems  

NASA Technical Reports Server (NTRS)

Exchanging heat between hot and cold streams within an advanced life support system can save energy. This savings will reduce the equivalent system mass (ESM) of the system. Different system configurations are examined under steady-state conditions for various percentages of food growth and waste treatment. The scenarios investigated represent possible design options for a Mars reference mission. Reference mission definitions are drawn from the ALSS Modeling and Analysis Reference Missions Document, which includes definitions for space station evolution, Mars landers, and a Mars base. For each scenario, streams requiring heating or cooling are identified and characterized by mass flow, supply and target temperatures and heat capacities. The Pinch Technique is applied to identify good matches for energy exchange between the hot and cold streams and to calculate the minimum external heating and cooling requirements for the system. For each pair of hot and cold streams that are matched, there will be a reduction in the amount of external heating and cooling required, and the original heating and cooling equipment will be replaced with a heat exchanger. The net cost savings can be either positive or negative for each stream pairing, and the priority for implementing each pairing can be ranked according to its potential cost savings. Using the Pinch technique, a complete system heat exchange network is developed and heat exchangers are sized to allow for calculation of ESM. The energy-integrated design typically has a lower total ESM than the original design with no energy integration. A comparison of ESM savings in each of the scenarios is made to direct future Pinch Analysis efforts.

Levri, Julie; Finn, Cory

2000-01-01

286

Craniospinal Irradiation Techniques: A Dosimetric Comparison of Proton Beams With Standard and Advanced Photon Radiotherapy  

SciTech Connect

Purpose: To evaluate the dosimetric benefits of advanced radiotherapy techniques for craniospinal irradiation in cancer in children. Methods and Materials: Craniospinal irradiation (CSI) using three-dimensional conformal radiotherapy (3D-CRT), tomotherapy (TOMO), and proton beam treatment (PBT) in the scattering mode was planned for each of 10 patients at our institution. Dosimetric benefits and organ-specific radiation-induced cancer risks were based on comparisons of dose-volume histograms (DVHs) and on the application of organ equivalent doses (OEDs), respectively. Results: When we analyzed the organ-at-risk volumes that received 30%, 60%, and 90% of the prescribed dose (PD), we found that PBT was superior to TOMO and 3D-CRT. On average, the doses delivered by PBT to the esophagus, stomach, liver, lung, pancreas, and kidney were 19.4 Gy, 0.6 Gy, 0.3 Gy, 2.5 Gy, 0.2 Gy, and 2.2 Gy for the PD of 36 Gy, respectively, which were significantly lower than the doses delivered by TOMO (22.9 Gy, 4.5 Gy, 6.1 Gy, 4.0 Gy, 13.3 Gy, and 4.9 Gy, respectively) and 3D-CRT (34.6 Gy, 3.6 Gy, 8.0 Gy, 4.6 Gy, 22.9 Gy, and 4.3 Gy, respectively). Although the average doses delivered by PBT to the chest and abdomen were significantly lower than those of 3D-CRT or TOMO, these differences were reduced in the head-and-neck region. OED calculations showed that the risk of secondary cancers in organs such as the stomach, lungs, thyroid, and pancreas was much higher when 3D-CRT or TOMO was used than when PBT was used. Conclusions: Compared with photon techniques, PBT showed improvements in most dosimetric parameters for CSI patients, with lower OEDs to organs at risk.

Yoon, Myonggeun, E-mail: radioyoon@gmail.com [Proton Therapy Center, National Cancer Center, Goyang (Korea, Republic of); Shin, Dong Ho [Proton Therapy Center, National Cancer Center, Goyang (Korea, Republic of); Kim, Jinsung [Department of Radiation Oncology, Samsung Medical Center, Seoul (Korea, Republic of); Kim, Jong Won; Kim, Dae Woong; Park, Sung Yong; Lee, Se Byeong; Kim, Joo Young [Proton Therapy Center, National Cancer Center, Goyang (Korea, Republic of); Park, Hyeon-Jin; Park, Byung Kiu [Pediatric Oncology Clinic, Center for Specific Organs Cancer, National Cancer Center, Goyang (Korea, Republic of); Shin, Sang Hoon [Neuro-Oncology Clinic, Center for Specific Organs Cancer, National Cancer Center, Goyang (Korea, Republic of)

2011-11-01

287

Advances in turbulent mixing techniques to study microsecond protein folding reactions  

PubMed Central

Recent experimental and computational advances in the protein folding arena have shown that the readout of the one-dimensional sequence information into three-dimensional structure begins within the first few microseconds of folding. The initiation of refolding reactions has been achieved by several means, including temperature jumps, flash photolysis, pressure jumps and rapid mixing methods. One of the most commonly used means of initiating refolding of chemically-denatured proteins is by turbulent flow mixing with refolding dilution buffer, where greater than 99% mixing efficiency has been achieved within 10’s of microseconds. Successful interfacing of turbulent flow mixers with complementary detection methods, including time-resolved Fluorescence Spectroscopy (trFL), Förster Resonance Energy Transfer (FRET), Circular Dichroism (CD), Small-Angle X-ray Scattering (SAXS), Hydrogen Exchange (HX) followed by Mass Spectrometry (MS) and Nuclear Magnetic Resonance Spectroscopy (NMR), Infrared Spectroscopy (IR), and Fourier Transform IR Spectroscopy (FTIR), has made this technique very attractive for monitoring various aspects of structure formation during folding. Although continuous-flow (CF) mixing devices interfaced with trFL detection have a dead time of only 30 µs, burst-phases have been detected in this time scale during folding of peptides and of large proteins (e.g., CheY and TIM barrels). Furthermore, a major limitation of CF mixing technique has been the requirement of large quantities of sample. In this brief communication, we will discuss the recent flurry of activity in micromachining and microfluidics, guided by computational simulations, that are likely to lead to dramatic improvements in time resolution and sample consumption for CF mixers over the next few years. PMID:23868289

Kathuria, Sagar V.; Chan, Alexander; Graceffa, Rita; Nobrega, R. Paul; Matthews, C. Robert; Irving, Thomas C.; Perot, Blair; Bilsel, Osman

2013-01-01

288

Analysis of deformation patterns through advanced DINSAR techniques in Istanbul megacity  

NASA Astrophysics Data System (ADS)

As result of the Turkey's economic growth and heavy migration processes from rural areas, Istanbul has experienced a high urbanization rate, with severe impacts on the environment in terms of natural resources pressure, land-cover changes and uncontrolled sprawl. As a consequence, the city became extremely vulnerable to natural and man-made hazards, inducing ground deformation phenomena that threaten buildings and infrastructures and often cause significant socio-economic losses. Therefore, the detection and monitoring of such deformation patterns is of primary importance for hazard and risk assessment as well as for the design and implementation of effective mitigation strategies. Aim of this work is to analyze the spatial distribution and temporal evolution of deformations affecting the Istanbul metropolitan area, by exploiting advanced Differential SAR Interferometry (DInSAR) techniques. In particular, we apply the Small BAseline Subset (SBAS) approach to a dataset of 43 TerraSAR-X images acquired, between November 2010 and June 2012, along descending orbits with an 11-day revisit time and a 3 m × 3 m spatial resolution. The SBAS processing allowed us to remotely detect and monitor subsidence patterns over all the urban area as well as to provide detailed information at the scale of the single building. Such SBAS measurements, effectively integrated with ground-based monitoring data and thematic maps, allows to explore the relationship between the detected deformation phenomena and urbanization, contributing to improve the urban planning and management.

Balik Sanli, F.; Calò, F.; Abdikan, S.; Pepe, A.; Gorum, T.

2014-09-01

289

On Advanced Estimation Techniques for Exoplanet Detection and Characterization using Ground-Based Coronagraphs  

NASA Technical Reports Server (NTRS)

The direct imaging of planets around nearby stars is exceedingly difficult. Only about 14 exoplanets have been imaged to date that have masses less than 13 times that of Jupiter. The next generation of planet-finding coronagraphs, including VLT-SPHERE, the Gemini Planet Imager, Palomar P1640, and Subaru HiCIAO have predicted contrast performance of roughly a thousand times less than would be needed to detect Earth-like planets. In this paper we review the state of the art in exoplanet imaging, most notably the method of Locally Optimized Combination of Images (LOCI), and we investigate the potential of improving the detectability of faint exoplanets through the use of advanced statistical methods based on the concepts of the ideal observer and the Hotelling observer. We provide a formal comparison of techniques through a blind data challenge and evaluate performance using the Receiver Operating Characteristic (ROC) and Localization ROC (LROC) curves. We place particular emphasis on the understanding and modeling of realistic sources of measurement noise in ground-based AO-corrected coronagraphs. The work reported in this paper is the result of interactions between the co-authors during a week-long workshop on exoplanet imaging that was held in Squaw Valley, California, in March of 2012.

Lawson, Peter R.; Frazin, Richard; Barrett, Harrison; Caucci, Luca; Devaney, Nicholas; Furenlid, Lars; Gladysz, Szymon; Guyon, Olivier; Krist, John; Maire, Jerome; Marois, Christian; Mawet, Dimitri; Mouillet, David; Mugnier, Laurent; Perrin, Marshall; Poyneer, Lisa; Pueyo, Laurent; Savransky, Dmitry; Soummer, Remi

2012-01-01

290

On Advanced Estimation Techniques for Exoplanet Detection and Characterization using Ground-based Coronagraphs  

NASA Technical Reports Server (NTRS)

The direct imaging of planets around nearby stars is exceedingly difficult. Only about 14 exoplanets have been imaged to date that have masses less than 13 times that of Jupiter. The next generation of planet-finding coronagraphs, including VLT-SPHERE, the Gemini Planet Imager, Palomar P1640, and Subaru HiCIAO have predicted contrast performance of roughly a thousand times less than would be needed to detect Earth-like planets. In this paper we review the state of the art in exoplanet imaging, most notably the method of Locally Optimized Combination of Images (LOCI), and we investigate the potential of improving the detectability of faint exoplanets through the use of advanced statistical methods based on the concepts of the ideal observer and the Hotelling observer. We propose a formal comparison of techniques using a blind data challenge with an evaluation of performance using the Receiver Operating Characteristic (ROC) and Localization ROC (LROC) curves. We place particular emphasis on the understanding and modeling of realistic sources of measurement noise in ground-based AO-corrected coronagraphs. The work reported in this paper is the result of interactions between the co-authors during a week-long workshop on exoplanet imaging that was held in Squaw Valley, California, in March of 2012

Lawson, Peter; Frazin, Richard

2012-01-01

291

Advanced techniques and painless procedures for nonlinear contact analysis and forming simulation via implicit FEM  

NASA Astrophysics Data System (ADS)

Nonlinear contact analysis including forming simulation via finite element methods has a crucial and practical application in many engineering fields. However, because of high nonlinearity, nonlinear contact analysis still remains as an extremely challenging obstacle for many industrial applications. The implicit finite element scheme is generally more accurate than the explicit finite element scheme, but it has a known challenge of convergence because of complex geometries, large relative motion and rapid contact state change. It might be thought as a very painful process to diagnose the convergence issue of nonlinear contact. Most complicated contact models have a great many contact surfaces, and it is hard work to well define the contact pairs using the common contact definition methods, which either result in hundreds of contact pairs or are time-consuming. This paper presents the advanced techniques of nonlinear contact analysis and forming simulation via the implicit finite element scheme and the penalty method. The calculation of the default automatic contact stiffness is addressed. Furthermore, this paper presents the idea of selection groups to help easily and efficiently define contact pairs for complicated contact analysis, and the corresponding implementation and usage are discussed. Lastly, typical nonlinear contact models and forming models with nonlinear material models are shown in the paper to demonstrate the key presented method and technologies.

Zhuang, Shoubing

2013-05-01

292

Advanced real-time dynamic scene generation techniques for improved performance and fidelity  

NASA Astrophysics Data System (ADS)

Recent advances in real-time synthetic scene generation for Hardware-in-the-loop (HWIL) testing at the U.S. Army Aviation and Missile Command (AMCOM) Aviation and Missile Research, Development, and Engineering Center (AMRDEC) improve both performance and fidelity. Modeling ground target scenarios requires tradeoffs because of limited texture memory for imagery and limited main memory for elevation data. High- resolution insets have been used in the past to provide better fidelity in specific areas, such as in the neighborhood of a target. Improvements for ground scenarios include smooth transitions for high-resolution insets to reduce high spatial frequency artifacts at the borders of the inset regions and dynamic terrain paging to support large area databases. Transport lag through the scene generation system, including sensor emulation and interface components, has been dealt with in the past through the use of sub-window extraction from oversize scenes. This compensates for spatial effects of transport lag but not temporal effects. A new system has been developed and used successfully to compensate for a flashing coded beacon in the scene. Other techniques have been developed to synchronize the scene generator with the seeker under test (SUT) and to model atmospheric effects, sensor optic and electronics, and angular emissivity attenuation.

Bowden, Mark H.; Buford, James A.; Mayhall, Anthony J.

2000-07-01

293

On advanced estimation techniques for exoplanet detection and characterization using ground-based coronagraphs  

NASA Astrophysics Data System (ADS)

The direct imaging of planets around nearby stars is exceedingly difficult. Only about 14 exoplanets have been imaged to date that have masses less than 13 times that of Jupiter. The next generation of planet-finding coronagraphs, including VLT-SPHERE, the Gemini Planet Imager, Palomar P1640, and Subaru HiCIAO have predicted contrast performance of roughly a thousand times less than would be needed to detect Earth-like planets. In this paper we review the state of the art in exoplanet imaging, most notably the method of Locally Optimized Combination of Images (LOCI), and we investigate the potential of improving the detectability of faint exoplanets through the use of advanced statistical methods based on the concepts of the ideal observer and the Hotelling observer. We propose a formal comparison of techniques using a blind data challenge with an evaluation of performance using the Receiver Operating Characteristic (ROC) and Localization ROC (LROC) curves. We place particular emphasis on the understanding and modeling of realistic sources of measurement noise in ground-based AO-corrected coronagraphs. The work reported in this paper is the result of interactions between the co-authors during a week-long workshop on exoplanet imaging that was held in Squaw Valley, California, in March of 2012.

Lawson, Peter R.; Poyneer, Lisa; Barrett, Harrison; Frazin, Richard; Caucci, Luca; Devaney, Nicholas; Furenlid, Lars; G?adysz, Szymon; Guyon, Olivier; Krist, John; Maire, Jérôme; Marois, Christian; Mawet, Dimitri; Mouillet, David; Mugnier, Laurent; Pearson, Iain; Perrin, Marshall; Pueyo, Laurent; Savransky, Dmitry

2012-07-01

294

Classification of human colonic tissues using FTIR spectra and advanced statistical techniques  

NASA Astrophysics Data System (ADS)

One of the major public health hazards is colon cancer. There is a great necessity to develop new methods for early detection of cancer. If colon cancer is detected and treated early, cure rate of more than 90% can be achieved. In this study we used FTIR microscopy (MSP), which has shown a good potential in the last 20 years in the fields of medical diagnostic and early detection of abnormal tissues. Large database of FTIR microscopic spectra was acquired from 230 human colonic biopsies. Five different subgroups were included in our database, normal and cancer tissues as well as three stages of benign colonic polyps, namely, mild, moderate and severe polyps which are precursors of carcinoma. In this study we applied advanced mathematical and statistical techniques including principal component analysis (PCA) and linear discriminant analysis (LDA), on human colonic FTIR spectra in order to differentiate among the mentioned subgroups' tissues. Good classification accuracy between normal, polyps and cancer groups was achieved with approximately 85% success rate. Our results showed that there is a great potential of developing FTIR-micro spectroscopy as a simple, reagent-free viable tool for early detection of colon cancer in particular the early stages of premalignancy among the benign colonic polyps.

Zwielly, A.; Argov, S.; Salman, A.; Bogomolny, E.; Mordechai, S.

2010-04-01

295

APPLICATION OF ADVANCED IN VITRO TECHNIQUES TO MEASURE, UNDERSTAND AND PREDICT THE KINETICS AND MECHANISMS OF XENOBIOTIC METABOLISM  

EPA Science Inventory

We have developed a research program in metabolism that involves numerous collaborators across EPA as well as other federal and academic labs. A primary goal is to develop and apply advanced in vitro techniques to measure, understand and predict the kinetics and mechanisms of xen...

296

Development of urban area geospatial information products from high resolution satellite imagery using advanced image analysis techniques  

Microsoft Academic Search

The latest generation of commercial satellite imaging sensors have a number of characteristics (e.g. high spatial resolution, multispectral bands, and quick revisit time), that make them ideal data sources for a variety of urban area applications. The goal of this doctoral research was to develop advanced automated and semi-automated image analysis and classification techniques for the extraction of urban area

Aaron K. Shackelford

2004-01-01

297

Techniques Optimized for Reducing Instabilities in Advanced Nickel-Base Superalloys for Turbine Blades  

NASA Technical Reports Server (NTRS)

The High-Speed Research (HSR) Airfoil Alloy program developed fourth-generation single-crystal superalloys with up to an 85 F increase in creep rupture capability over current production airfoil alloys. Recent results have been generated at the NASA Glenn Research Center on these fourth-generation alloys, but in coated form, for subsonic turbine blade applications under NASA's Ultra-Efficient Engine Technology (UEET) Program. One goal for UEET is to optimize the airfoil alloy/thermal barrier coating system for 3100 F turbine inlet temperatures. The state-of-the art turbine blade airfoil system consists of a superalloy single crystal that provides the basic mechanical performance of the airfoil. A thermal barrier coating is used to reduce the temperature of the base superalloy, and a bondcoat is deposited between the base material and the thermal barrier coating. The bondcoat improves the oxidation and corrosion resistance of the base superalloy and improves the spallation resistance of the thermal barrier coating. A commercial platinum aluminide bondcoat was applied to the HSR-developed alloys, and a diffusion zone developed as a result of interaction between the bondcoat and the superalloy. Optimized strength is obtained for superalloys when the refractory element content is high and the limits of microstructural stability are approached or exceeded slightly. For fourthgeneration alloys, instability leads to the formation of topologically close packed (TCP) phases, which form internally in the superalloy, and a secondary reaction zone (SRZ), which forms under the diffusion zone. There was a concern that excessive quantities of either TCP or SRZ might decrease the mechanical properties of the superalloy, with SRZ thought to be particularly detrimental and its formation unpredictable. Thus, an SRZreduction effort was initiated in the NASA UEET Program so that methods developed during the HSR project could be optimized further to reduce or eliminate the SRZ. An SRZ is a three-phase constituent composed of TCP and stringers of gamma phase in a matrix of gamma prime. An incoherent grain boundary separates the SRZ from the gammagamma prime microstructure of the superalloy. The SRZ is believed to form as a result of local chemistry changes in the superalloy due to the application of the diffusion aluminide bondcoat. Locally high surface stresses also appear to promote the formation of the SRZ. Thus, techniques that change the local alloy chemistry or reduce surface stresses have been examined for their effectiveness in reducing SRZ. These SRZ-reduction steps are performed on the test specimen or the turbine blade before the bondcoat is applied. Stressrelief heat treatments developed at NASA Glenn have been demonstrated to reduce significantly the amount of SRZ that develops during subsequent high-temperature exposures. Stress-relief heat treatments reduce surface stresses by recrystallizing a thin surface layer of the superalloy. However, in alloys with very high propensities to form SRZ, stress relief heat treatments alone do not eliminate SRZ entirely. Thus, techniques that modify the local chemistry under the bondcoat have been emphasized and optimized successfully at Glenn. One such technique is carburization, which changes the local chemistry by forming submicron carbides near the surface of the superalloy. Detailed characterizations have demonstrated that the depth and uniform distribution of these carbides are enhanced when a stress relief treatment and an appropriate surface preparation are employed in advance of the carburization treatment. Even in alloys that have the propensity to develop a continuous SRZ layer beneath the diffusion zone, the SRZ has been completely eliminated or reduced to low, manageable levels when this combination of techniques is utilized. Now that the techniques to mitigate SRZ have been established at Glenn, TCP phase formation is being emphasized in ongoing work under the UEET Program. The limitsf stability of the fourth-generation alloys with respect to TCP phase formation are currently bei

MacKay, Rebecca A.; Locci, Ivan E.; Garg, anita; Ritzert, Frank J.

2002-01-01

298

Simultaneous Velocity/Passive Scalar Measurements Using a Molecular Tagging Technique  

NASA Astrophysics Data System (ADS)

A new approach is described for simultaneous whole-field measurements of velocity and passive scalar in a water flow. This approach combines the traditional LIF technique for concentration measurements (e.g. based on using fluorescein as a tracer) with Molecular Tagging Velocimetry (MTV) using a water-soluble phosphorescent compound. It is shown that one can design experiments with minimal cross-talk between the LIF and MTV signals. We demonstrate preliminary applications in a low Reynolds number forced wake and a perturbed turbulent mixing layer. In the former simultaneous maps of mixing interfaces and the spanwise vorticity field are presented. In the case of the mixing layer, preliminary data are given for the mean and fluctuating components of the velocity and concentration fields, and the velocity/concentration correlations.

Koochesfahani, Manoochehr; MacKinnon, Colin

1998-11-01

299

A molecular fingerprint technique to detect pollution-related changes in river cyanobacterial diversity.  

PubMed

Humans now have a strong influence on almost every major aquatic ecosystem, and our activities have dramatically altered the quality of receiving waters worldwide. Thus, there is a continuous need to develop and apply novel and effective technologies to detect, manage, and correct human-induced degradation of aquatic systems. In the present work, we evaluated the molecular approach using polymerase chain reaction (PCR)-temperature gradient gel electrophoresis (TGGE) to measure changes in cyanobacterial diversity along a pollution gradient in a river and compared it with that of using microscopic observations of field-fixed and cultured samples. The different 16S rDNA genes present in the cyanobacterial community of each sampling point of the river were separated by TGGE, giving a characteristic pattern of bands for each site. This pattern represents a "fingerprint" of the community, allowing direct comparisons of the different samples. The TGGE results revealed that the structure of the cyanobacterial community differed along the pollution gradient of the river. Microscopic and molecular approaches showed that cyanobacterial diversity decreased in a downstream direction. Similar results were obtained by the two methods, as indicated by the high correlation between them. We suggest PCR-TGGE could be a useful and rapidly applied technique for the routine analysis of changes in cyanobacterial diversity in response to pollution, which would allow us to monitor rivers in surveillance networks of watercourse quality. PMID:17255634

Rodríguez, Virginia; de Cárcer, Daniel Aguirre; Loza, Virginia; Perona, Elvira; Mateo, Pilar

2007-01-01

300

Design, modeling and control of a piezoelectric ultrasonic microdissection technique for the molecular analysis of tissue  

NASA Astrophysics Data System (ADS)

Molecular techniques are transforming our understanding of cellular function and disease. However, accurate molecular analysis methods will be limited if the input DNA, RNA or protein is not derived from a pure population of cells or is contaminated by the wrong cells. The modeling and control of the piezoelectric actuator, with an objective application towards ultrasonic vibration cutting (UVC), is addressed in this paper. The piezoelectric actuator is used in realizing the fast and precise movements of the developed UVC so as to procure a pure population of targeted cells from tissue sections for subsequent pathology analysis with precision and without causing a large deformation. To address the nonlinearities and uncertainties of the piezoelectric actuator, an adaptive controller based on a hysteresis model is proposed to yield robust control performance. A multilayer piezoelectric actuator is used to actuate a sharp needle vibrating at high frequency and low amplitude to cut the tissue. Experimental results showed that the embedded tissue can be quickly and precisely cut with this ultrasonic vibration microdissection method.

Chen, Liguo; Ru, Changhai; Rong, Weibin; Liu, Yaxin; Sun, Lining

2010-02-01

301

Inquiry-based learning: inflammation as a model to teach molecular techniques for assessing gene expression.  

PubMed

This laboratory module simulates the process used by working scientists to ask and answer a question of biological interest. Instructors facilitate acquisition of knowledge using a comprehensive, inquiry-based approach in which students learn theory, hypothesis development, experimental design, and data interpretation and presentation. Using inflammation in macrophages as a model system, students perform a series of molecular biology techniques to address the biological question: "Does stimulus 'X' induce inflammation?" To ask this question, macrophage cells are treated with putative inflammatory mediators and then assayed for evidence of inflammatory response. Students become familiar with their assigned mediator and the relationship between their mediator and inflammation by conducting literature searches, then using this information to generate hypotheses which address the effect of their mediator on induction of inflammation. The cellular and molecular approaches used to test their hypotheses include transfection and luciferase reporter assay, immunoblot, fluorescence microscopy, enzyme-linked immunosorbent assay, and quantitative PCR. Quantitative and qualitative reasoning skills are developed through data analysis and demonstrated by successful completion of post-lab worksheets and the generation and oral presentation of a scientific poster. Learning objective assessment relies on four instruments: pre-lab quizzes, post-lab worksheets, poster presentation, and posttest. Within three cohorts (n = 85) more than 95% of our students successfully achieved the learning objectives. PMID:24358382

Gunn, Kathryn E; McCauslin, Christine Seitz; Staiger, Jennifer; Pirone, Dana M

2013-01-01

302

Use of molecular epidemiological techniques in a pilot study on workers exposed to chromium.  

PubMed Central

OBJECTIVES--Molecular epidemiological techniques, capable of detecting damage to DNA, were used to see if such damage occurred in the lymphocytes of a group of workers exposed to chromium. The two aims of this pilot study were to see if these new techniques might make useful biological monitoring tools for workers exposed to chromium and also, to help assess whether the current occupational exposure limit for chromium (VI) was sufficiently protective in this specific working situation. METHODS--Volunteer groups of 10 workers exposed to chromium and 10 non-exposed workers provided urine and blood samples towards the end of the working week. Chromium concentrations were measured in whole blood, plasma, lymphocytes, and urine. Lymphocytes were used to examine two forms of DNA damage in the two groups; these were the level of DNA strand breakage and, the production of 8-hydroxydeoxyguanosine. RESULTS--Chromium concentration in whole blood, plasma, and urine of workers exposed to chromium was significantly raised (P < 0.01) compared with non-exposed controls, but in isolated lymphocytes, there was only a modest but significant (P < 0.05) increase in chromium in the group exposed to chromium. There was no difference in the levels of DNA strand breaks or 8-hydroxydeoxyguanosine between the groups. Air monitoring for chromium was not undertaken but current levels for the group exposed to chromium were reported to be around 0.01 mg/m3, which is 20% of the current United Kingdom occupational exposure limit. CONCLUSIONS--We were unable to detect any damage in lymphocytic DNA due to exposure to chromium. This may have been due to the low chromium exposure (< 20% of the United Kingdom occupational exposure limit), the ability of plasma to detoxify chromium (VI) to chromium (III) before it reached the lymphocytes, or perhaps the insensitivity of the molecular techniques used. It is now important to test these and other such techniques on groups exposed to levels closer to the United Kingdom occupational exposure limit. PMID:8000490

Gao, M; Levy, L S; Faux, S P; Aw, T C; Braithwaite, R A; Brown, S S

1994-01-01

303

The advanced qualtiy control techniques planned for the Internation Soil Moisture Network  

NASA Astrophysics Data System (ADS)

In situ soil moisture observations are essential to evaluate and calibrate modeled and remotely sensed soil moisture products. Although a number of meteorological networks and field campaigns measuring soil moisture exist on a global and long-term scale, their observations are not easily accessible and lack standardization of both technique and protocol. Thus, handling and especially comparing these datasets with satellite products or land surface models is a demanding issue. To overcome these limitations the International Soil Moisture Network (ISMN; http://www.ipf.tuwien.ac.at/insitu/) has been initiated to act as a centralized data hosting facility. One advantage of the ISMN is that users are able to access the harmonized datasets easily through a web portal. Another advantage is the fully automated processing chain including the data harmonization in terms of units and sampling interval, but even more important is the advanced quality control system each measurement has to run through. The quality of in situ soil moisture measurements is crucial for the validation of satellite- and model-based soil moisture retrievals; therefore a sophisticated quality control system was developed. After a check for plausibility and geophysical limits a quality flag is added to each measurement. An enhanced flagging mechanism was recently defined using a spectrum based approach to detect spurious spikes, jumps and plateaus. The International Soil Moisture Network has already evolved to one of the most important distribution platforms for in situ soil moisture observations and is still growing. Currently, data from 27 networks in total covering more than 800 stations in Europe, North America, Australia, Asia and Africa is hosted by the ISMN. Available datasets also include historical datasets as well as near real-time measurements. The improved quality control system will provide important information for satellite-based as well as land surface model-based validation studies.

Xaver, A.; Gruber, A.; Hegiova, A.; Sanchis-Dufau, A. D.; Dorigo, W. A.

2012-04-01

304

Advanced Sensing and Control Techniques to Facilitate Semi-Autonomous Decommissioning  

SciTech Connect

This research is intended to advance the technology of semi-autonomous teleoperated robotics as applied to Decontamination and Decommissioning (D&D) tasks. Specifically, research leading to a prototype dual-manipulator mobile work cell is underway. This cell is supported and enhanced by computer vision, virtual reality and advanced robotics technology.

Schalkoff, Robert J.

1999-06-01

305

Tetrode technology: advances in implantable hardware, neuroimaging, and data analysis techniques  

Microsoft Academic Search

The technical advances in hardware and software for multiunit recordings have made it easier to gather data from a large number of neurons for behavioral correlations. This paper discusses several such advances in implantable hardware, magnetic resonance imaging of electrodes in situ, and data analysis software for multiple simultaneous signals.

M. S. Jog; C. I. Connolly; Y. Kubota; D. R. Iyengar; L. Garrido; R. Harlan; A. M. Graybiel

2002-01-01

306

The Kinetochore Moves Ahead: Contributions of Molecular and Genetic Techniques to Our Understanding of Mitosis  

NSDL National Science Digital Library

Cell division is necessary to the building of a soma from the single-celled zygote during development, as well as the sine qua non, in the form of meiosis, for the evolutionary success of species. Here we review recent progress in our understanding of a key player, the kinetochore, in these processes. The kinetochore is both the anchor to the mitotic spindle for chromosomes at division and the motor for distribution of chromosomal units to daughter cells. In addition, the kinetochore plays a key role in the molecular checkpoints of cell-cycle progression. Although the nucleation of the kinetochore at a chromosomal site is under epigenetic control, the underlying base sequence of the DNA at the centromere is not critical: The assembly of the kinetochore occurs at exactly the same place on the same chromosomes at every division cycle. We discuss recent advances in our understanding of how the kinetochore is organized and assembled, as well as how it contributes to critical cell-cycle checkpoints and to chromosome movement.

Mary Kathrine Johnson (Mississippi State University;Department of Biological Sciences); Dwayne Wise (Mississippi State University;Department of Biological Sciences)

2009-12-01

307

Pulmonary adenocarcinoma: implications of the recent advances in molecular biology, treatment and the IASLC/ATS/ERS classification  

PubMed Central

A decade ago, lung cancer could conveniently be classified into two broad categories—either the small cell lung carcinoma (SCLC), or the non-small cell lung carcinoma (NSCLC), mainly to assist in further treatment related decision making. However, the understanding regarding the eligibility of adenocarcinoma histology for treatments with agents such as pemetrexed and bevacizumab made it a necessity for NSCLC to be classified into more specific sub-groups. Then, the availability of molecular targeted therapy with oral tyrosine kinase inhibitors (TKIs) such as gefitinib and erlotinib not only further emphasized the need for accurate sub-classification of lung cancer, but also heralded the important role of molecular profiling of lung adenocarcinomas. Given the remarkable advances in molecular biology, oncology and radiology, a need for felt for a revised classification for lung adenocarcinoma, since the existing World Health Organization (WHO) classification of lung cancer, published in the year 2004 was mainly a pathological system of classification. Thus, there was a combined effort by the International Association for the Study of Lung Cancer (IASLC), the American Thoracic Society (ATS) and the European Respiratory Society (ERS) with an effort to inculcate newly established perspectives from clinical, molecular and radiological aspects in evolving a modern classification for lung adenocarcinomas. This review provides a summary of the recent advances in molecular biology and molecular targeted therapy with respect to lung adenocarcinoma. Also, a brief summation of the salient recommendations provided in the IASLC/ATS/ERS classification of lung adenocarcinomas is provided. Lastly, a discussion regarding the future prospects with lung adenocarcinoma is included.

Thakur, Priyanka; Bhardwaj, Bhaskar; Susheela, Sridhar Papaiah; Madabhavi, Irappa

2014-01-01

308

Pulmonary adenocarcinoma: implications of the recent advances in molecular biology, treatment and the IASLC/ATS/ERS classification.  

PubMed

A decade ago, lung cancer could conveniently be classified into two broad categories-either the small cell lung carcinoma (SCLC), or the non-small cell lung carcinoma (NSCLC), mainly to assist in further treatment related decision making. However, the understanding regarding the eligibility of adenocarcinoma histology for treatments with agents such as pemetrexed and bevacizumab made it a necessity for NSCLC to be classified into more specific sub-groups. Then, the availability of molecular targeted therapy with oral tyrosine kinase inhibitors (TKIs) such as gefitinib and erlotinib not only further emphasized the need for accurate sub-classification of lung cancer, but also heralded the important role of molecular profiling of lung adenocarcinomas. Given the remarkable advances in molecular biology, oncology and radiology, a need for felt for a revised classification for lung adenocarcinoma, since the existing World Health Organization (WHO) classification of lung cancer, published in the year 2004 was mainly a pathological system of classification. Thus, there was a combined effort by the International Association for the Study of Lung Cancer (IASLC), the American Thoracic Society (ATS) and the European Respiratory Society (ERS) with an effort to inculcate newly established perspectives from clinical, molecular and radiological aspects in evolving a modern classification for lung adenocarcinomas. This review provides a summary of the recent advances in molecular biology and molecular targeted therapy with respect to lung adenocarcinoma. Also, a brief summation of the salient recommendations provided in the IASLC/ATS/ERS classification of lung adenocarcinomas is provided. Lastly, a discussion regarding the future prospects with lung adenocarcinoma is included. PMID:25349702

Revannasiddaiah, Swaroop; Thakur, Priyanka; Bhardwaj, Bhaskar; Susheela, Sridhar Papaiah; Madabhavi, Irappa

2014-10-01

309

New AFM Techniques for Investigating Molecular Growth Mechanisms of Protein Crystals  

NASA Technical Reports Server (NTRS)

Atomic Force Microscopy (AFM) has emerged as a powerful technique for investigating protein crystal growth. Earlier AFM studies were among the first to demonstrate that these crystals grew by dislocation and 2D nucleation growth mechanisms [1]. These investigations were restricted to the micron range where only surface features, such as dislocation hillocks and 2D islands are visible. Most AFM instruments can scan at higher resolutions and have the potential to resolve individual protein molecules at nanometer ranges. Such scans are essential for determining the molecular packing arrangements on crystal faces and for probing the growth process at the molecular level. However, at this resolution the AFM tip influences the image produced, with the resulting image being a convolution of the tip shape and the surface morphology [2]. In most studies this problem is resolved by deconvoluting the image to obtain the true surface morphology. Although deconvolution routines work reasonably well for simple one- dimensional shapes, for complex surfaces this approach does not produce accurate results. In this study we devised a new approach which takes advantage of the precise molecular order of crystal surfaces, combined with the knowledge of individual molecular shapes from the crystallographic data of the protein and the AFM tip shape. This information is used to construct expected theoretical AFM images by convoluting the tip shape with the constructed crystal surface shape for a given surface packing arrangement. By comparing the images from actual AFM scans with the constructed ones for different possible surface packing arrangements, the correct packing arrangement can be conclusively determined. This approach was used in this study to determine the correct one from two possible packing arrangements on (I 10) faces of tetragonal lysozyme crystals. Another novel AFM technique was also devised to measure the dimension of individual growth units of the crystal faces. Measuring these units was not attempted before and most studies have assumed that the growth unit consisted of individual protein molecules. The linescan mode of AFM instruments allows the crystal surface to be scanned along a single line. By scanning across a growth step an image showing the motion of the step is obtained. Normally such an image shows a straight line for continuous and constant step velocity. In this study by increasing the scan rate and by decreasing the step velocity (by decreasing the supersaturation), we were able to capture images of individual growth events, shown by jump discontinuities in the step line. By suitable integration of the image the growth unit dimension in the scanned direction can be obtained. Since multiple units can be involved in the growth process it is necessary to collect a statistically relevant sample before drawing conclusions about the growth mechanism. This technique was successfully employed to obtain the dimensions of growth units for the (110) face, showing that they consisted of various aggregates corresponding to the 43 helices in the crystal structure.

Li, Huayu; Nadarajah, Arunan; Konnert, John H.; Pusey, Marc L.

1998-01-01

310

Chloride Molecular Doping Technique on 2D Materials: WS2 and MoS2.  

PubMed

Low-resistivity metal-semiconductor (M-S) contact is one of the urgent challenges in the research of 2D transition metal dichalcogenides (TMDs). Here, we report a chloride molecular doping technique which greatly reduces the contact resistance (Rc) in the few-layer WS2 and MoS2. After doping, the Rc of WS2 and MoS2 have been decreased to 0.7 k?·?m and 0.5 k?·?m, respectively. The significant reduction of the Rc is attributed to the achieved high electron-doping density, thus a significant reduction of Schottky barrier width. As a proof-of-concept, high-performance few-layer WS2 field-effect transistors (FETs) are demonstrated, exhibiting a high drain current of 380 ?A/?m, an on/off ratio of 4 × 10(6), and a peak field-effect mobility of 60 cm(2)/(V·s). This doping technique provides a highly viable route to diminish the Rc in TMDs, paving the way for high-performance 2D nanoelectronic devices. PMID:25310177

Yang, Lingming; Majumdar, Kausik; Liu, Han; Du, Yuchen; Wu, Heng; Hatzistergos, Michael; Hung, P Y; Tieckelmann, Robert; Tsai, Wilman; Hobbs, Chris; Ye, Peide D

2014-11-12

311

The characterization of Leishmania parasites and their vectors from Central America using molecular techniques.  

PubMed

The disfiguring cutaneous and mucocutaneous and often fatal visceral forms of leishmaniasis are an increasing public health problem in Central America. There are some evidences of a highest prevalence of L. braziliensis and L. mexicana in Guatemala; L. braziliensis, L. panamensis and L. infantum (L. chagasi) in Honduras and Nicaragua, and L. panamensis in Costa Rica and Panamá. Our research project, just starting, attempts to use molecular approaches for a more rapid and accurate diagnosis and to identify the parasites. The techniques include non-radioactive DNA probes, PCR, schizodeme, isoenzyme analysis and monoclonal antibodies; and specific recombinant peptides will be used to improve immunodiagnosis of the visceral form. Intra-specific heterogeneity in Leishmania isolates will be examined by pulsed field electrophoresis and random amplified polymorphic DNA. Using selected strains, the techniques will be compared on a regional basis leading to a better knowledge of parasite distribution and the related clinical entities. Furthermore, DNA probes for the identification of parasites in vectors and for sibling species of vectors, are also to be applied; chemical identification of sandfly male pheromones will be attempted possibly leading to potential novel control measures. PMID:7802486

Zeledón, R; Maingon, R; Ward, R; Arana, B; Belli, A; de Carreira, P; Ponce, C

1993-01-01

312

Low-mass molecular dynamics simulation: A simple and generic technique to enhance configurational sampling.  

PubMed

CLN025 is one of the smallest fast-folding proteins. Until now it has not been reported that CLN025 can autonomously fold to its native conformation in a classical, all-atom, and isothermal-isobaric molecular dynamics (MD) simulation. This article reports the autonomous and repeated folding of CLN025 from a fully extended backbone conformation to its native conformation in explicit solvent in multiple 500-ns MD simulations at 277K and 1atm with the first folding event occurring as early as 66.1ns. These simulations were accomplished by using AMBER forcefield derivatives with atomic masses reduced by 10-fold on Apple Mac Pros. By contrast, no folding event was observed when the simulations were repeated using the original AMBER forcefields of FF12SB and FF14SB. The results demonstrate that low-mass MD simulation is a simple and generic technique to enhance configurational sampling. This technique may propel autonomous folding of a wide range of miniature proteins in classical, all-atom, and isothermal-isobaric MD simulations performed on commodity computers-an important step forward in quantitative biology. PMID:25181342

Pang, Yuan-Ping

2014-09-26

313

An advanced technique for speciation of organic nitrogen in atmospheric aerosols  

NASA Astrophysics Data System (ADS)

The chemical composition of organic nitrogen (ON) in the environment is a research topic of broad significance. The topic intersects the branches of atmospheric, aquatic, and ecological science; thus, a variety of instrumentation, analytical methods, and data interpretation tools have evolved for determination of ON. Recent studies that focus on atmospheric particulate nitrogen (N) suggest a significant fraction (20-80%) of total N is bound in organic compounds. The sources, bioavailability and transport mechanisms of these N-containing compounds can differ, producing a variety of environmental consequences. Amino acids (AA) are a key class of atmospheric ON compounds that can contribute to secondary organic aerosol (SOA) formation and potentially influence water cycles, air pollutant scavenging, and the radiation balance. AA are water-soluble organic compounds (WSOC) that can significantly alter the acid-base chemistry of aerosols, and may explain the buffering capacity that impacts heterogeneous atmospheric chemistry. The chemical transformations that N-containing organic compounds (including AA) undergo can increase the light-absorbing capacity of atmospheric carbon via formation of 'brown carbon'. Suggested sources of atmospheric AA include: marine surface layer transport from bursting sea bubbles, the suspension of bacteria, fungi, algae, pollen, spores, or biomass burning. Methodology for detection of native (underivatized) amino acids (AA) in atmospheric aerosols has been developed and validated (Samy et al., 2011). This presentation describes the use of LC-MS (Q-TOF) and microwave-assisted gas phase hydrolysis for detection of free and combined amino acids in aerosols collected in a Southeastern U.S. forest environment. Accurate mass detection and the addition of isotopically labeled surrogates prior to sample preparation allows for sensitive quantitation of target AA in a complex aerosol matrix. A total of 16 native AA were detected above the reporting threshold as water-soluble free AA, with an average concentration of 22 ± 9 ng m-3 (N=13). Following microwave-assisted gas phase hydrolysis, the total AA concentration in the forest environment increased significantly (70 ± 35 ng m-3) and additional compounds (methionine, isoleucine) were detected above the reporting threshold. The ability to quantify AA in aerosol samples without derivatization reduces time consuming preparation procedures while providing the advancement of selective mass determination that eliminates potential interferences associated with traditional fluorescence detection. This step forward in precise mass determination with the use of internal standardization, improves the confidence of compound identification. With the increasing focus on WSOC (including ON) characterization in the atmospheric science community, native detection by LC-MS (Q-TOF) will play a central role in determining the most direct approach to quantify an increasing fraction of the co-extracted polar organic compounds. Method application for further characterization of atmospheric ON will be discussed. Reference: Samy, S., Robinson, J., and M.D. Hays. "An Advanced LC-MS (Q-TOF) Technique for the Detection of Amino Acids in Atmospheric Aerosols", Analytical Bioanalytical Chemistry, 2011, DOI: 10.1007/s00216-011-5238-2

Samy, S.; Robinson, J.; Hays, M. D.

2011-12-01

314

Investigation of Advanced Dose Verification Techniques for External Beam Radiation Treatment  

NASA Astrophysics Data System (ADS)

Intensity modulated radiation therapy (IMRT) and volumetric modulated arc therapy (VMAT) have been introduced in radiation therapy to achieve highly conformal dose distributions around the tumour while minimizing dose to surrounding normal tissues. These techniques have increased the need for comprehensive quality assurance tests, to verify that customized patient treatment plans are accurately delivered during treatment. in vivo dose verification, performed during treatment delivery, confirms that the actual dose delivered is the same as the prescribed dose, helping to reduce treatment delivery errors. in vivo measurements may be accomplished using entrance or exit detectors. The objective of this project is to investigate a novel entrance detector designed for in vivo dose verification. This thesis is separated into three main investigations, focusing on a prototype entrance transmission detector (TRD) developed by IBA Dosimetry, Germany. First contaminant electrons generated by the TRD in a 6 MV photon beam were investigated using Monte Carlo (MC) simulation. This study demonstrates that modification of the contaminant electron model in the treatment planning system is required for accurate patient dose calculation in buildup regions when using the device. Second, the ability of the TRD to accurately measure dose from IMRT and VMAT was investigated by characterising the spatial resolution of the device. This was accomplished by measuring the point spread function with further validation provided by MC simulation. Comparisons of measured and calculated doses show that the spatial resolution of the TRD allows for measurement of clinical IMRT fields within acceptable tolerance. Finally, a new general research tool was developed to perform MC simulations for VMAT and IMRT treatments, simultaneously tracking dose deposition in both the patient CT geometry and an arbitrary planar detector system, generalized to handle either entrance or exit orientations. It was demonstrated that the tool accurately simulates dose to the patient CT and planar detector geometries. The tool has been made freely available to the medical physics research community to help advance the development of in vivo planar detectors. In conclusion, this thesis presents several investigations that improve the understanding of a novel entrance detector designed for patient in vivo dosimetry.

Asuni, Ganiyu Adeniyi

315

Advanced in situ Spectroscopic Techniques And Their Applications In Environmental Biogeochemistry: Introduction To The Special Section  

EPA Science Inventory

Understanding the molecular-scale complexities and interplay of chemical and biological processes of contaminants at solid, liquid, and gas interfaces is a fundamental and crucial element to enhance our understanding of anthropogenic environmental impacts. The ability to describ...

316

Experimental and molecular docking studies on DNA binding interaction of adefovir dipivoxil: Advances toward treatment of hepatitis B virus infections  

NASA Astrophysics Data System (ADS)

The toxic interaction of adefovir dipivoxil with calf thymus DNA (CT-DNA) was investigated in vitro under simulated physiological conditions by multi-spectroscopic techniques and molecular modeling study. The fluorescence spectroscopy and UV absorption spectroscopy indicated drug interacted with CT-DNA in a groove binding mode. The binding constant of UV-visible and the number of binding sites were 3.33 ± 0.2 × 104 L mol-1and 0.99, respectively. The fluorimetric studies showed that the reaction between the drug and CT-DNA is exothermic (?H = 34.4 kJ mol-1; ?S = 184.32 J mol-1 K-1). Circular dichroism spectroscopy (CD) was employed to measure the conformational change of CT-DNA in the presence of adefovir dipivoxil, which verified the groove binding mode. Furthermore, the drug induces detectable changes in its viscosity. The molecular modeling results illustrated that adefovir strongly binds to groove of DNA by relative binding energy of docked structure -16.83 kJ mol-1. This combination of multiple spectroscopic techniques and molecular modeling methods can be widely used in the investigation on the toxic interaction of small molecular pollutants and drugs with bio macromolecules, which contributes to clarify the molecular mechanism of toxicity or side effect in vivo.

Shahabadi, Nahid; Falsafi, Monireh

317

Removal of Lattice Imperfections that Impact the Optical Quality of Ti:Sapphire using Advanced Magnetorheological Finishing Techniques  

SciTech Connect

Advanced magnetorheological finishing (MRF) techniques have been applied to Ti:sapphire crystals to compensate for sub-millimeter lattice distortions that occur during the crystal growing process. Precise optical corrections are made by imprinting topographical structure onto the crystal surfaces to cancel out the effects of the lattice distortion in the transmitted wavefront. This novel technique significantly improves the optical quality for crystals of this type and sets the stage for increasing the availability of high-quality large-aperture sapphire and Ti:sapphire optics in critical applications.

Menapace, J A; Schaffers, K I; Bayramian, A J; Davis, P J; Ebbers, C A; Wolfe, J E; Caird, J A; Barty, C J

2008-02-26

318

Advances in analytical techniques for polychlorinated dibenzo-p-dioxins, polychlorinated dibenzofurans and dioxin-like PCBs  

PubMed Central

Analytical techniques for the determination of polychorinated dibenzo-p-dioxins (PCDD), polychlorinated dibenzofurans (PCDF) and dioxin-like PCBs (DLPCB) are reviewed. The focus of the review is on recent advances in methodology and analytical procedures. The paper also reviews toxicology, the development of toxic equivalent factors (TEF) and the determination of toxic equivalent quantity (TEQ) values. Sources, occurrence and temporal trends of PCDD/PCDF are summarized to provide examples of levels and concentration ranges for the methods and techniques reviewed. PMID:16794816

Clement, Ray E.; Okey, Allan B.; Marvin, Chris H.

2006-01-01

319

Advanced characterization techniques of nonuniform indium distribution within InGaN\\/GaN heterostructures grown by MOCVD  

Microsoft Academic Search

Nonuniform indium distribution within InGaN\\/GaN single quantum well (SQW) structures with nanoscale islands grown by metalorganic chemical vapor deposition (MOCVD) have been characterized by advanced characterization techniques. Robinson backscattered electron (BSE) measurements show cluster-like BSE contrast of high brightness regions, which are not centered at small dark pits in a SQW structure of spiral growth mode. By comparing with the

D. Lu; D. I. Florescu; D. S. Lee; J. C. Ramer; A. Parekh; V. Merai; S. Li; J. J. Gardner; M. J. Begarney; E. A. Armour

2005-01-01

320

Joint IAMAS\\/IAHS symposium J1 on global monitoring and advanced observing techniques in the atmosphere and hydrosphere  

Microsoft Academic Search

Seventy papers were presented at the two-and-a-half-day Symposium on Global Monitoring and Advanced Observing Techniques in the Atmosphere and Hydrosphere. The symposium was jointly organized by the International Association of Meteorology and Atmospheric Sciences (IAMAS) and the International Association of Hydrological Sciences (IAHS) and took place in Yokohama, Japan, 13-15 July 1993, as part of the IAMAS\\/IAHS Join Assembly. Global

G. Ohring; T. Aoki; D. Halpern; A. Henderson-Sellers; T. Charlock; J. Joseph; K. Labitzke; E. Raschke; W. Smith

1994-01-01

321

Advances in remote inference of physical and biological parameters using acoustic scattering techniques: Mapping the ocean in broadband "color".  

PubMed

Active narrowband acoustic scattering techniques have been used for decades to infer the distribution of marine organisms, such as fish and zooplankton, and to image physical processes, such as bubbles, suspended sediments, internal waves, and microstructure. Accurately inferring relevant biological and physical parameters from the acoustic returns, such as size or abundance of organisms or intensity of mixing, has represented a far more formidable obstacle, requiring a multi-faceted approach in order to make significant headway. Over the years, advances have been made in understanding the fundamental scattering physics, resulting in more robust and accurate scattering models. These models have been guided and tested by controlled laboratory scattering experiments as well as in a plethora of field experiments. Rapid advances in instrumentation and deployment platforms have also enabled new insights to be gained. In this presentation, a brief overview of this research area is given, results from the development and implementation of broadband scattering techniques for studying physical and biological processes over relevant spatial and temporal scales are presented, and limitations of these techniques considered. Possible future directions and advances in the area of remote physical and biological parameter estimation from active acoustic scattering data will be discussed. PMID:25235666

Lavery, Andone C

2014-04-01

322

The impact of molecular morphology techniques on the expert diagnosis in melanocytic skin neoplasms.  

PubMed

Thirteen melanocytic skin neoplasms with a consultation diagnosis by A. Bernard Ackerman were submitted to immunohistochemistry for HMB-45, Ki67, cyclin D1, e-cadherin, and p16; 9/13 cases underwent fluorescence in situ hybridization (FISH) test targeting 6p25 (RREB1), 6q23 (MYB), centromere 6 (Cep6), and 11q13 (CCND1), as well as the centromere 7 (Cep7). A "consensus diagnosis" among 3 experts was also advocated both before and after morphomolecular information. Three neoplasms with a consultation diagnosis of Spitz nevus showed at least 3 abnormal immunohistochemical patterns; 2 of these cases were also FISH-positive for CCND1 gain, but none of them had a final consensus diagnosis of melanoma. Two neoplasms with a consultation diagnosis of congenital nevus received a consensus diagnosis of melanoma. Molecular morphology techniques can highlight the atypical features of melanocytic neoplasms and support existence of a morphobiologic "spectrum": This should be mirrored in the final report by abandoning the dichotomic (benign vs malignant) diagnostic approach. PMID:23775023

Ferrara, Gerardo; Misciali, Cosimo; Brenn, Thomas; Cerroni, Lorenzo; Kazakov, Dmitry W; Perasole, Antonio; Russo, Rosa; Ricci, Roberto; Crisman, Giuliana; Fanti, Pier Alessandro; Passarini, Beatrice; Patrizi, Annalisa

2013-10-01

323

Fungal diversity in maritime Antarctic soils determined using a combination of culture isolation, molecular fingerprinting and cloning techniques  

Microsoft Academic Search

The diversity and phylogenetic relationships of fungi obtained from Antarctic soils were analysed using molecular techniques. Direct extraction of soil community DNA from two locations, Fossil Bluff (FB) and Jane Col (JC), was supplemented with isolation studies. Nucleic acids from both the community DNA and the colony extracts were PCR amplified using primers specific for the 18S rRNA gene (18S

Elaine Malosso; Ian S. Waite; Lorna English; David W. Hopkins; Anthony G. O’Donnell

2006-01-01

324

ION-MOLECULAR EQUILIBRIUM TECHNIQUE APPLYED TO Cr O AND NiO ACTIVITY DETERMINATION. GIBBS ENERGY OF FORMATION OF  

E-print Network

- 1 - ION-MOLECULAR EQUILIBRIUM TECHNIQUE APPLYED TO Cr O AND 2 3 NiO ACTIVITY DETERMINATION. GIBBS ENERGY OF FORMATION OF NiCr O . 2 4 RUDNYI E.B., KAIBICHEVA E.A., SIDOROV L.N. Department of Chemistry, Ur. Depart. Academy of science of USSR, Sverdlovsk, 620219, U.S.S.R. Short title - "GIBBS ENERGY

Rudnyi, Evgenii B.

325

Adaptations of advanced safety and reliability techniques to petroleum and other industries  

NASA Technical Reports Server (NTRS)

The underlying philosophy of the general approach to failure reduction and control is presented. Safety and reliability management techniques developed in the industries which have participated in the U.S. space and defense programs are described along with adaptations to nonaerospace activities. The examples given illustrate the scope of applicability of these techniques. It is indicated that any activity treated as a 'system' is a potential user of aerospace safety and reliability management techniques.

Purser, P. E.

1974-01-01

326

Advances in the Use of Synchrotron-Based Techniques to Elucidate Biogeochemical Processes in Natural Systems  

E-print Network

; climate change impacts on contaminant cycling; and particulate transport. Examples of some numerous honors and awards including Fellow of the Soil Science Society of America, the American Society of Agronomy, the American Association for the Advancement of Science, the Geochemical Society

Sparks, Donald L.

327

Exploring Advanced Techniques for Training an Artificial Neural Network on a Complex,  

E-print Network

advances in "deep learning" are the most notable ex- ception. Neural nets can also suffer from the issue was that learning how to make use of this expert knowledge would prove an easier task than learning the problem from of the oldest and most versatile algorithms for machine learning. Academics and industry professionals have

Meeden, Lisa A.

328

Oncoplastic technique in breast conservative surgery for locally advanced breast cancer  

PubMed Central

Locally advanced breast cancer (LABC) should be taken into decision making when planning breast conservative surgery, but this procedure should be done on the principle of oncologic safety in order to achieve negative surgical margin and maintain aesthetic result. This procedure should be offered as the choice of treatment in selected patients. PMID:25083490

Kongdan, Youwanush; Vassanasiri, Wichai; Ratchaworapong, Kampol; Sukarayothin, Thongchai; Supsamutchai, Chairat; Klaiklern, Phatarachate; Leesombatpaiboon, Monchai; Hamza, Alaa; Zurrida, Stefano

2014-01-01

329

Advance Appropriations: A Needless and Confusing Education Budget Technique. Federal Education Budget Project  

ERIC Educational Resources Information Center

This report argues that advance appropriations serve no functional purpose for schools, but they create a loss of transparency, comparability, and simplicity in federal education budgeting. It allocates spending before future budgets have been established. The approach was originally used to skirt spending limits and budget procedures in place…

Delisle, Jason

2007-01-01

330

The Application of Novel Failure Analysis Techniques for Advanced Multi-Layered CMOS Devices  

Microsoft Academic Search

The major focus of this paper is on innovative fault localisation approaches that make use of DFT (design for testability) features, fanin tree, assembly code programming and functional model simulation as FA tools. Besides these, defect localisation techniques and revolutionary backside FA techniques are discussed. All these tools enhance FA activities and increase the chance of defect detection. Without these

Yeoh Eng Hong; Martin Tay Tiong We

1997-01-01

331

Advanced plasma fluctuation analysis techniques and their impact on fusion research (invited)  

Microsoft Academic Search

This article reviews digital spectral analysis techniques that yield experimental insight into plasma turbulence. Methods to quantify the statistical properties of the fluctuations and to measure the particle and heat flux caused by electrostatic fluctuations are presented. Furthermore, analysis techniques to study the nonlinear coupling process of turbulence and the redistribution of energy among the different modes are discussed. The

Ch. P. Ritz; E. J. Powers; T. L. Rhodes; R. D. Bengtson; K. W. Gentle; Hong Lin; P. E. Phillips; A. J. Wootton; D. L. Brower; N. C. Luhmann Jr.; W. A. Peebles; P. M. Schoch; R. L. Hickok

1988-01-01

332

Advanced techniques for noise source identification on a large generator unit  

SciTech Connect

Power station acoustic noise assessment, which has experienced increased environmental awareness and subsequently more stringent legislation for a number of years, has received and added stimulus due to the recent advent of powerful measurement and analysis techniques including sound intensity and coherence. These experimental techniques are explained and results, for a generator unit, illustrate their value in providing a unique, correlated insight into noise problems. This includes noise quantification, full explanation of site sound pressure level in terms of the various influences and major noise source identification. These techniques are widely applicable and an invaluable aid to any industrial noise problem.

Williams, R.G.D. (GEC Alsthom Turbine Generator Ltd., Stafford (United Kingdom)); Yang, S.J. (Heriot-Watt Univ., Edinburgh (United Kingdom))

1993-03-01

333

External Magnetic Field Reduction Techniques for the Advanced Stirling Radioisotope Generator  

NASA Technical Reports Server (NTRS)

Linear alternators coupled to high efficiency Stirling engines are strong candidates for thermal-to-electric power conversion in space. However, the magnetic field emissions, both AC and DC, of these permanent magnet excited alternators can interfere with sensitive instrumentation onboard a spacecraft. Effective methods to mitigate the AC and DC electromagnetic interference (EMI) from solenoidal type linear alternators (like that used in the Advanced Stirling Convertor) have been developed for potential use in the Advanced Stirling Radioisotope Generator. The methods developed avoid the complexity and extra mass inherent in data extraction from multiple sensors or the use of shielding. This paper discusses these methods, and also provides experimental data obtained during breadboard testing of both AC and DC external magnetic field devices.

Niedra, Janis M.; Geng, Steven M.

2013-01-01

334

Understanding the interaction between valsartan and detergents by NMR techniques and molecular dynamics simulation.  

PubMed

Valsartan (VST) is one of the Angiotensin II receptor antagonists, which is widely used in clinical hypertension treatment. It is believed that VST incorporates into biological membranes before it binds to AT(1) receptor. Herein the interactions between VST and detergents, mimicking the membrane environment, were investigated by using nuclear magnetic resonance (NMR) techniques and molecular dynamics (MD) simulation. We observed that VST has two conformers (trans and cis) exchanging slowly in DPC (dodecyl-phosphocholine) micelles, a widely used detergent. The changes of chemical shifts, relaxation rates, and self-diffusion coefficients of VST protons indicate that both conformers have strong interactions with DPC. NOE cross peaks and MD simulation reveal that DPC interacts with VST not only through the hydrophobic lipid chain, but also the hydrophilic headgroup, locating VST at the charged headgroup and upper part of the micelles. Our results are in good agreement with the Raman spectroscopic studies of VST in the DPPC (dipalmitoyl-phosphatidylcholine) bilayers by Potamitis et al. (Biochim. Biophys. Acta. 2011). The concentration ratio of trans over cis conformers is 0.94, showing that two conformers have the same affinities with the detergent, which is significantly smaller than our previous results obtained in SDS (sodium dodecyl sulfate) micelles. MD simulation suggested that the cis conformer has slightly lower binding free energy than the trans conformer when interacting with DPC. The conformational change of VST was further investigated in two detergents, CTAB (hexadecyltrimethylammonium bromide) and Tween-20 (polysorbate 20). Ratios of conformer A and B in the presence of detergents are in the order of DPC, CTAB < Tween-20 < SDS, which is correlated with the charge characters of their head groups. NMR investigations and MD simulations indicate that the electrostatic interaction plays an essential role in the binding process of VST with detergents, and the hydrophobic interaction influences the packing of the drug in the micelles. These results may be of help in understanding delivery processes of sartan drugs in cell membranes. PMID:22708715

Cao, Chenyu; Mao, Jiezhen; Li, Fang; Yang, Minghui; He, Hongqing; Jiang, Ling; Liu, Maili

2012-06-28

335

Video Coding Using a Simplified Block Structure and Advanced Coding Techniques  

Microsoft Academic Search

This paper describes a new video coding scheme based on a simplified block structure that significantly outperforms the coding efficiency of the ISO\\/IEC 14496-10 $vert{rm ITU}hbox{-}{rm T}$ H.264 advanced video coding (AVC) standard. Its conceptual design is similar to a typical block-based hybrid coder applying prediction and subsequent prediction error coding. The basic coding unit is an 8 $,times,$8 block

Frank Bossen; Virginie Drugeon; Edouard François; Joel Jung; Sandeep Kanumuri; Matthias Narroschke; Hisao Sasai; Joel Solé; Yoshinori Suzuki; Thiow Keng Tan; Thomas Wedi; Steffen Wittmann; Peng Yin; Yunfei Zheng

2010-01-01

336

Advanced real-time dynamic scene generation techniques for improved performance and fidelity  

Microsoft Academic Search

Recent advances in real-time synthetic scene generation for Hardware-in-the-loop (HWIL) testing at the U.S. Army Aviation and Missile Command (AMCOM) Aviation and Missile Research, Development, and Engineering Center (AMRDEC) improve both performance and fidelity. Modeling ground target scenarios requires tradeoffs because of limited texture memory for imagery and limited main memory for elevation data. High- resolution insets have been used

Mark H. Bowden; James A. Buford; Anthony J. Mayhall

2000-01-01

337

Recent advances in freeze-fracture electron microscopy: the replica immunolabeling technique  

PubMed Central

Freeze-fracture electron microscopy is a technique for examining the ultrastructure of rapidly frozen biological samples by transmission electron microscopy. Of a range of approaches to freeze-fracture cytochemistry that have been developed and tried, the most successful is the technique termed freeze-fracture replica immunogold labeling (FRIL). In this technique, samples are frozen, fractured and replicated with platinum-carbon as in standard freeze fracture, and then carefully treated with sodium dodecylsulphate to remove all the biological material except a fine layer of molecules attached to the replica itself. Immunogold labeling of these molecules permits their distribution to be seen superimposed upon high resolution planar views of membrane structure. Examples of how this technique has contributed to our understanding of lipid droplet biogenesis and function are discussed. PMID:18385807

2008-01-01

338

An overview on in situ micronization technique – An emerging novel concept in advanced drug delivery  

PubMed Central

The use of drug powders containing micronized drug particles has been increasing in several pharmaceutical dosage forms to overcome the dissolution and bioavailability problems. Most of the newly developed drugs are poorly water soluble which limits dissolution rate and bioavailability. The dissolution rate can be enhanced by micronization of the drug particles. The properties of the micronized drug substance such as particle size, size distribution, shape, surface properties, and agglomeration behaviour and powder flow are affected by the type of micronization technique used. Mechanical communition, spray drying and supercritical fluid (SCF) technology are the most commonly employed techniques for production of micronized drug particles but the characteristics of the resulting drug product cannot be controlled using these techniques. Hence, a newer technique called in situ micronization is developed in order to overcome the limitations associated with the other techniques. This review summarizes the existing knowledge on in situ micronization techniques. The properties of the resulting drug substance obtained by in situ micronization were also compared. PMID:25161371

Vandana, K.R.; Prasanna Raju, Y.; Harini Chowdary, V.; Sushma, M.; Vijay Kumar, N.

2013-01-01

339

Molecular diagnosis of soft tissue neoplasia: clinical applications and recent advances.  

PubMed

Sarcomas are rare and heterogeneous neoplasms of mesenchymal tissues with diverse morphologies and clinical behavior. In the last few years, the discovery of specific genetic aberrations in these tumors has allowed better classification and understanding of mechanisms driving their pathogenesis. While the majority of sarcomas are still treated by traditional modalities, molecular markers driving the pathogenesis have paved the way for more accurate diagnosis and opportunity to explore other therapeutic strategies. This review discusses the available molecular tools in sarcoma diagnostics and highlight some of the biological significance of the recent discoveries and their clinical applications. PMID:25109831

Hameed, Meera

2014-11-01

340

Recent advances in the genetic epidemiology and molecular genetics of substance use disorders  

Microsoft Academic Search

This article reviews current advances in the genetics of substance use disorders (SUDs). Both genetic and environmental sources of risk are required to develop a complete picture of SUD etiology. Genetic sources of risk for SUDs are not highly substance specific in their effects. Genetic and environmental risks for SUDs typically do not only add together but also interact with

Xiangning Chen; Danielle Dick; Hermine Maes; Nathan Gillespie; Michael C Neale; Brien Riley; Kenneth S Kendler

2012-01-01

341

Targeting brain cancer: advances in the molecular pathology of malignant glioma and medulloblastoma  

Microsoft Academic Search

Malignant brain tumours continue to be the cause of a disproportionate level of morbidity and mortality across a wide range of individuals. The most common variants in the adult and paediatric populations — malignant glioma and medulloblastoma, respectively — have been the subject of increasingly intensive research over the past two decades that has led to considerable advances in the

Jason T. Huse; Eric C. Holland

2010-01-01

342

Combining quantum wavepacket ab initio molecular dynamics with QM/MM and QM/QM techniques: Implementation blending ONIOM and empirical  

E-print Network

, ab initio molecular dynamics, and the ONIOM scheme. We utilize this method to include nuclear quantumCombining quantum wavepacket ab initio molecular dynamics with QM/MM and QM/QM techniques/QM generalizations to our recently developed quantum wavepacket ab initio molecular dynamics methodology

Iyengar, Srinivasan S.

343

2010NatureAmerica,Inc.Allrightsreserved. NATURE STRUCTURAL & MOLECULAR BIOLOGY ADVANCE ONLINE PUBLICATION 1  

E-print Network

to mediate infection and the capacity of a particular New World clade B arenavirus to cause human disease19 independently and fortuitously acquired their ability to bind human TfR1 and hence to cause human disease. 1Laboratory of Molecular Medicine and 2Department of Medicine, Children's Hospital, Harvard Medical School

Harrison, Stephen C.

344

POC-SCALE TESTING OF AN ADVANCED FINE COAL DEWATERING EQUIPMENT/TECHNIQUE  

SciTech Connect

Dewatering of ultra-fine (minus 150 {micro}m) coal slurry to less than 20% moisture is difficult using the conventional dewatering techniques. The main objective of the project was to evaluate a novel surface modification technique, which utilizes the synergistic effect of metal ions and surfactants in combination for the dewatering of ultra-fine clean-coal slurries using various dewatering techniques on a proof-of-concept (POC) scale of 0.5 to 2 tons per hour. The addition of conventional reagents and the application of coal surface modification technique were evaluated using vacuum filtration, hyperbaric (pressure) filtration, ceramic plate filtration and screen-bowl centrifuge techniques. The laboratory and pilot-scale dewatering studies were conducted using the fine-size, clean-coal slurry produced in the column flotation circuit at the Powell Mountain Coal Company, St. Charles, VA. The pilot-scale studies were conducted at the Mayflower preparation plant in St. Charles, VA. The program consisted of nine tasks, namely, Task 1--Project Work Planning, Task 2--Laboratory Testing, Task 3--Engineering Design, Task 4--Procurement and Fabrication, Task 5--Installation and Shakedown, Task 6--System Operation, Task 7--Process Evaluation, Task 8--Equipment Removal, and Task 9--Reporting.

X.H. Wang; J. Wiseman; D.J. Sung; D. McLean; William Peters; Jim Mullins; John Hugh; G. Evans; Vince Hamilton; Kenneth Robinette; Tim Krim; Michael Fleet

1999-08-01

345

Joint IAMAS/IAHS Symposium J1 on Global Monitoring and Advanced Observing Techniques in the Atmosphere and Hydrosphere  

NASA Technical Reports Server (NTRS)

Seventy papers were presented at the two-and-a-half-day Symposium on Global Monitoring and Advanced Observing Techniques in the Atmosphere and Hydrosphere. The symposium was jointly organized by the International Association of Meteorology and Atmospheric Sciences (IAMAS) and the International Association of Hydrological Sciences (IAHS). Global observing systems are receiving increased attention in connection with such problems as monitoring global climate change. The symposium included papers on observational requirements; measurement methodologies; descriptions of available datasets; results of analysis of observational data; plans for future observing systems, including the Global Climate Observing System (GCOS) and the Global Ocean Observing System (GOOS); and the programs and plans of the space agencies.

Ohring, G.; Aoki, T.; Halpern D.; Henderson-Sellers, A.; Charlock, T.; Joseph, J.; Labitzke, K.; Raschke, E.; Smith, W.

1994-01-01

346

Application of advanced signal processing techniques to the rectification and registration of spaceborne imagery. [technology transfer, data transmission  

NASA Technical Reports Server (NTRS)

The development of an ERTS/MSS image processing system responsive to the needs of the user community is discussed. An overview of the TRW ERTS/MSS processor is presented, followed by a more detailed discussion of image processing functions satisfied by the system. The particular functions chosen for discussion are evolved from advanced signal processing techniques rooted in the areas of communication and control. These examples show how classical aerospace technology can be transferred to solve the more contemporary problems confronting the users of spaceborne imagery.

Caron, R. H.; Rifman, S. S.; Simon, K. W.

1974-01-01

347

Precision bone and muscle loss measurements by advanced, multiple projection DEXA (AMPDXA) techniques for spaceflight applications  

NASA Technical Reports Server (NTRS)

An advanced, multiple projection, dual energy x-ray absorptiometry (AMPDXA) scanner system is under development. The AMPDXA is designed to make precision bone and muscle loss measurements necessary to determine the deleterious effects of microgravity on astronauts as well as develop countermeasures to stem their bone and muscle loss. To date, a full size test system has been developed to verify principles and the results of computer simulations. Results indicate that accurate predictions of bone mechanical properties can be determined from as few as three projections, while more projections are needed for a complete, three-dimensional reconstruction. c 2001. Elsevier Science Ltd. All rights reserved.

Charles, H. K. Jr; Beck, T. J.; Feldmesser, H. S.; Magee, T. C.; Spisz, T. S.; Pisacane, V. L.

2001-01-01

348

Advanced analysis technique for the evaluation of linear alternators and linear motors  

NASA Astrophysics Data System (ADS)

A method for the mathematical analysis of linear alternator and linear motor devices and designs is described, and an example of its use is included. The technique seeks to surpass other methods of analysis by including more rigorous treatment of phenomena normally omitted or coarsely approximated such as eddy braking, non-linear material properties, and power losses generated within structures surrounding the device. The technique is broadly applicable to linear alternators and linear motors involving iron yoke structures and moving permanent magnets. The technique involves the application of Amperian current equivalents to the modeling of the moving permanent magnet components within a finite element formulation. The resulting steady state and transient mode field solutions can simultaneously account for the moving and static field sources within and around the device.

Holliday, Jeffrey C.

1995-12-01

349

Advanced analysis technique for the evaluation of linear alternators and linear motors  

NASA Technical Reports Server (NTRS)

A method for the mathematical analysis of linear alternator and linear motor devices and designs is described, and an example of its use is included. The technique seeks to surpass other methods of analysis by including more rigorous treatment of phenomena normally omitted or coarsely approximated such as eddy braking, non-linear material properties, and power losses generated within structures surrounding the device. The technique is broadly applicable to linear alternators and linear motors involving iron yoke structures and moving permanent magnets. The technique involves the application of Amperian current equivalents to the modeling of the moving permanent magnet components within a finite element formulation. The resulting steady state and transient mode field solutions can simultaneously account for the moving and static field sources within and around the device.

Holliday, Jeffrey C.

1995-01-01

350

Advanced, time-resolved imaging techniques for electron-beam characterizations  

SciTech Connect

Several unique time-resolved imaging techniques have been developed to address radio frequency (RF)-linac generated electron beams and the free-electron lasers (FEL) driven by such systems. The time structures of these beams involve a series of micropulses with 10 to 15-ps duration, separated by tens of nanoseconds. Mechanisms to convert the e-beam information to optical radiation include optical transition radiation (OTR), Cherenkov radiation, spontaneous emission radiation (SER), and the FEL mechanism itself. The use of gated, intensified television cameras and synchroscan and dual-sweep streak cameras to time-resolve these signals has greatly enhanced the power of these techniques. A brief review of the less familiar conversion mechanisms and electro-optic techniques is followed by a series of specific experimental examples from the RF linac FEL facilities at Los Alamos and Boeing (Seattle, WA). 23 refs., 35 figs., 3 tabs.

Lumpkin, A.H.

1990-01-01

351

Image enhancement and advanced information extraction techniques for ERTS-1 data  

NASA Technical Reports Server (NTRS)

The author has identified the following significant results. It was demonstrated and concluded that: (1) the atmosphere has significant effects on ERTS MSS data which can seriously degrade recognition performance; (2) the application of selected signature extension techniques serve to reduce the deleterious effects of both the atmosphere and changing ground conditions on recognition performance; and (3) a proportion estimation algorithm for overcoming problems in acreage estimation accuracy resulting from the coarse spatial resolution of the ERTS MSS, was able to significantly improve acreage estimation accuracy over that achievable by conventional techniques, especially for high contrast targets such as lakes and ponds.

Malila, W. A. (principal investigator); Nalepka, R. F.; Sarno, J. E.

1975-01-01

352

Advanced model-based FDIR techniques for aerospace systems: Today challenges and opportunities  

NASA Astrophysics Data System (ADS)

This paper discusses some trends and recent advances in model-based Fault Detection, Isolation and Recovery (FDIR) for aerospace systems. The FDIR challenges range from pre-design and design stages for upcoming and new programs, to improvement of the performance of in-service flying systems. For space missions, optimization of flight conditions and safe operation is intrinsically related to GNC (Guidance, Navigation & Control) system of the spacecraft and includes sensors and actuators monitoring. Many future space missions will require autonomous proximity operations including fault diagnosis and the subsequent control and guidance recovery actions. For upcoming and future aircraft, one of the main issues is how early and robust diagnosis of some small and subtle faults could contribute to the overall optimization of aircraft design. This issue would be an important factor for anticipating the more and more stringent requirements which would come in force for future environmentally-friendlier programs. The paper underlines the reasons for a widening gap between the advanced scientific FDIR methods being developed by the academic community and technological solutions demanded by the aerospace industry.

Zolghadri, Ali

2012-08-01

353

Development of a real-time aeroperformance analysis technique for the X-29A advanced technology demonstrator  

NASA Technical Reports Server (NTRS)

The X-29A advanced technology demonstrator has shown the practicality and advantages of the capability to compute and display, in real time, aeroperformance flight results. This capability includes the calculation of the in-flight measured drag polar, lift curve, and aircraft specific excess power. From these elements many other types of aeroperformance measurements can be computed and analyzed. The technique can be used to give an immediate postmaneuver assessment of data quality and maneuver technique, thus increasing the productivity of a flight program. A key element of this new method was the concurrent development of a real-time in-flight net thrust algorithm, based on the simplified gross thrust method. This net thrust algorithm allows for the direct calculation of total aircraft drag.

Ray, R. J.; Hicks, J. W.; Alexander, R. I.

1988-01-01

354

Mobile and Stationary Computer Vision based Traffic Surveillance Techniques for Advanced ITS Applications  

Microsoft Academic Search

During the past decade, new sensing technologies, such as inductive loops, laser range scanners, radar detectors and computer vision sensors have been greatly enhanced and applied to the Intelligent Transportation System (ITS) area. Among all these sensor systems, computer vision-based approaches are one of the most popular and promising techniques used in ITS for traffic evaluation and management, driver assistance,

Meng Cao

2009-01-01

355

Detecting variable source areas from temporal radar imagery using advanced image enhancement techniques  

Microsoft Academic Search

Recently, N. E. C. Verhoest et al. (1998) showed that it is possible to map variable source areas in a catchment using a principal component analysis. This technique, based on a temporal series of images, revealed the spatial soil moisture patterns from the vegetation and topographic effects introduced in a synthetic aperture radar (SAR) image. However, the obtained image is

Aleksandra Pizurica; Niko E. C. Verhoest; Wilfried Philips; Francois P. De Troch

2000-01-01

356

ADVANCED TEM TECHNIQUES FOR ASSESSING THE POSSIBLE BIOGENIC ORIGIN OF METEORITIC MAGNETITE CRYSTALS. M. Weyland  

E-print Network

such as a Gatan Imaging Filter (GIF) is used to obtain chemical maps at sample tilt angles of up to ±60°. At each,3 edge. Chemical maps are then calculated using techniques based on electron energy loss spectroscopy (EELS). Figures 2a and b show reconstructions (viewed from a single di- rection) of the three

Dunin-Borkowski, Rafal E.

357

Identifying high amenity zones in the U.S. and China with advanced GIS techniques  

Microsoft Academic Search

This paper applies a variety of GIS techniques to examine the spatial pattern and extent of high amenity zones (HAZ) in selected cities of the U.S. and Guangzhou, China. HAZs are adjacent to downtowns and represent high density upscale residential areas whose residents support neighborhood retailing and service employment that can often result in the misclassification of the areas as

Richard P. Greene; Siqin Wang

2010-01-01

358

Magnetic resonance techniques in the evaluation of the perinatal brain: recent advances and future directions  

Microsoft Academic Search

Magnetic resonance (MR) techniques are attractive for use in the developing brain because of their resolving power and their relative noninvasiveness. Their ability to provide detailed structural as well as metabolic and functional information without the use of ionizing radiation is unique. Conventional MR Imaging has widely proven its potential for identifying normal and pathologic brain morphology. Functional MR imaging

Petra S. Huppi; Terrie E. Inder

2001-01-01

359

Applying advanced surface analysis techniques to small defect characterization on EUV ML blanks  

Microsoft Academic Search

Developing capability in detection, review, and characterization of sub-100 nm defects on EUV multilayer blanks has become critical in enabling the defect root-cause analysis and the eventual elimination of all defects. We have developed a functional method to apply surface analytical techniques (AES, SEM, EDX, and AFM) to characterize individual defects on EUV multilayer blanks. Optical defect inspection is first

Emily Y. Shu

2004-01-01

360

Advancement and Application of Gas Chromatography Isotope Ratio Mass Spectrometry Techniques for Atmospheric Trace Gas Analysis  

Microsoft Academic Search

The use of gas chromatography isotope ratio mass spectrometry (GC-IRMS) for compound specific stable isotope analysis is an underutilized technique because of the complexity of the instrumentation and high analytical costs. However stable isotopic data, when coupled with concentration measurements, can provide additional information on a compounds production, transformation, loss, and cycling within the biosphere and atmosphere. A GC-IRMS system

Brian M Giebel

2011-01-01

361

Microprobing the Molecular Spatial Distribution and Structural Architecture of Feed-type Sorghum Seed Tissue (Sorghum Bicolor L.) using the Synchrotron Radiation Infrared Microspectroscopy Technique  

SciTech Connect

Sorghum seed (Sorghum bicolor L.) has unique degradation and fermentation behaviours compared with other cereal grains such as wheat, barley and corn. This may be related to its cell and cell-wall architecture. The advanced synchrotron radiation infrared microspectroscopy (SR-IMS) technique enables the study of cell or living cell biochemistry within cellular dimensions. The objective of this study was to use the SR-IMS imaging technique to microprobe molecular spatial distribution and cell architecture of the sorghum seed tissue comprehensively. High-density mapping was carried out using SR-IMS on beamline U2B at the National Synchrotron Light Source (Brookhaven National Laboratory, NY, USA). Molecular images were systematically recorded from the outside to the inside of the seed tissue under various chemical functional groups and their ratios [peaks at {approx}1725 (carbonyl C=O ester), 1650 (amide I), 1657 (protein secondary structure {alpha}-helix), 1628 (protein secondary structure {beta}-sheet), 1550 (amide II), 1515 (aromatic compounds of lignin), 1428, 1371, 1245 (cellulosic compounds in plant seed tissue), 1025 (non-structural CHO, starch granules), 1246 (cellulosic material), 1160 (CHO), 1150 (CHO), 1080 (CHO), 930 (CHO), 860 (CHO), 3350 (OH and NH stretching), 2960 (CH{sub 3} anti-symmetric), 2929 (CH{sub 2} anti-symmetric), 2877 (CH{sub 3} symmetric) and 2848 cm{sup -1} (CH{sub 2} asymmetric)]. The relative protein secondary structure {alpha}-helix to {beta}-sheet ratio image, protein amide I to starch granule ratio image, and anti-symmetric CH{sub 3} to CH{sub 2} ratio image were also investigated within the intact sorghum seed tissue. The results showed unique cell architecture, and the molecular spatial distribution and intensity in the sorghum seed tissue (which were analyzed through microprobe molecular imaging) were generated using SR-IMS. This imaging technique and methodology has high potential and could be used for scientists to develop specific cereal grain varieties with targeted food and feed quality, and can also be used to monitor the degree of grain maturity, grain damage, the fate of organic contaminants and the effect of chemical treatment on plant and grain seeds.

P Yu

2011-12-31

362

Coupling isotopic, reporter and molecular techniques to verify links between plant C flow and denitrification  

NASA Astrophysics Data System (ADS)

Recent technical advances for quantifying denitrification rates, denitrifier-N2O:N2 product ratios and linking these to the underpinning microbiology, have provided new insights into interactions between C and N processes, and flexibility of microbial function in response to changing environmental conditions and management. The availability of organic C is considered paramount for the production and reduction of the greenhouse gas nitrous oxide (N2O) during denitrification in the rhizosphere. Despite this, the role of organic C in the regulation of N2O- and N2-genic enzymes is poorly understood. Stable isotopes are fundamental in resolving this. Here we will present selected results from experiments in which we have applied stable isotope techniques to verify the effect of plant C in driving denitrification, and the potential feedbacks of this on climate change. Changes in C input to soil, such as under elevated atmospheric CO2, is significant for N2O production and reduction. Following application of 15N-labelled fertiliser to Lolium perenne swards we showed increased denitrifier-N2O and N2 production under elevated pCO2 (60 Pa) in the Swiss FACE experiment. This was attributed to greater below ground C allocation providing the energy for denitrification, and emissions were strongly positively correlated with TOC. The N2-to-N2O ratio was also raised under elevated pCO2, which indicates important feedbacks effects are occurring with climate change, mediated through plant C flow. Little is known about the effect of different C substrates in regulating N2O and N2 production nor their effects on community structure, activity or species selection of denitrifying bacteria in the rhizosphere. We provide the first evidence for differences in N2O and N2 production with different C compounds typically present in root exudate, which suggest differences in regulation of the NO and N2O reductases, or preference for different C compounds in the rhizosphere denitrifier community. Such differences in gaseous N production are being related to the function and activity of the denitrifier community associated with this root C flow, with the link between C flow and denitrifier activity being verified by stable isotope probing and nanoSIMS imaging. Further ecophysiological evidence is presented of reporter gene expression by denitrifiers in response to different substrate classes of rhizosphere C.

Baggs, E.; Paterson, E.; Prendergast-Miller, M.; Morley, N.; Chadwick, K.; Killham, K.

2009-04-01

363

POC-scale testing of an advanced fine coal dewatering equipment/technique. Quarterly progress report, July - September 1996  

SciTech Connect

The advanced fine-coal cleaning techniques such as column flotation, recovers a low-ash ultra-fine size clean-coal product. However, economical dewatering of the clean coal product to less than 20 percent moisture using conventional technology is difficult. This research program objective is to evaluate a novel coal surface modification technique developed at the University of Kentucky Center for Applied Energy Research in conjunction with conventional and advanced dewatering technique at a pilot scale. The study which is in progress is being conducted at the Powell Mountain Coal Company`s Mayflower preparation plant located in St. Charles, VA. During this quarter laboratory dewatering studies were conducted using a 4-in diameter laboratory chemical centrifuge. The baseline data provided a filter cake with about 32% moisture. Addition of 0.3 kg/t of a cationic surfactant lowered the moisture to 29%. Addition of anionic and non-ionic surfactant was not effective in reducing the filter cake moisture content. In the pilot scale studies, a comparison was conducted between the high pressure and vacuum dewatering techniques. The base line data with high pressure and vacuum filtration provided filter cakes with 23.6% and 27.8% moisture, respectively. Addition of 20 g/t of cationic flocculent provided 21% filter cake moisture using the high pressure filter. A 15% moisture filter cake was obtained using 1.5 kg/t of non-ionic surfactant. Vacuum filter provided about 23% to 25% moisture product with additional reagents. The high pressure filter processed about 3 to 4 times more solids compared to vacuum filter.

Tao, D.; Groppo, J.G.; Parekh, B.K.

1996-10-01

364

Recent Advances And Future Prospective in Molecular Breeding of Cotton For Drought and Salinity Stress Tolerance  

Microsoft Academic Search

Fiber from cotton (Gossypium hirsutum and G. barbadense) is a major product in the world economy. It is a botanically unique plant as it is a perennial allotetraploid derived from\\u000a diploid Gossypium species, one of which does not produce lint, which is grown as an annual row crop. Cotton is an especially appropriate system\\u000a for research into the molecular basis

Edward L. Lubbers; Peng W. Chee; Yehoshua Saranga; Andrew H. Paterson

365

Technology Insight: advances in molecular imaging and an appraisal of PET\\/CT scanning  

Microsoft Academic Search

PET\\/CT imaging has rapidly emerged as an important imaging tool in oncology. The success of PET\\/CT imaging is based on several features. First, patients benefit from a comprehensive diagnostic anatomical and functional (molecular) whole-body survey in a single session. Second, PET\\/CT provides more-accurate diagnostic information than PET or CT alone. Third, PET\\/CT imaging allows radiation oncologists to use the functional

Anca L Grosu; Johannes Czernin; Wolfgang A Weber

2008-01-01

366

Midstromal isolated Bowman layer graft for reduction of advanced keratoconus: a technique to postpone penetrating or deep anterior lamellar keratoplasty.  

PubMed

Midstromal implant of an isolated Bowman layer graft is a new approach to reduce ectasia in eyes with advanced keratoconus. The procedure should postpone penetrating or deep anterior lamellar keratoplasty. Ten eyes of 9 patients with progressive, advanced keratoconus and contact lens intolerance underwent the procedure with no intraoperative adverse events. Throughout the study period, we observed no complications related to stromal dissection and/or the Bowman layer graft. Maximum corneal power decreased from a mean (SD) of 74.5 (7.1) diopters (D) before to 68.3 (5.6) D after surgery (P?=?.002). Hence, implant of an isolated Bowman layer graft may offer a safe and effective new technique to reduce ectasia in eyes with advanced keratoconus, potentially allowing continued long-term contact lens wear. The low risk of complications may render the procedure suitable as a treatment to postpone penetrating or deep anterior lamellar keratoplasty in cases with impending contact lens intolerance and/or corneal scarring (clinicaltrials.gov Identifier: NCT01686906). PMID:24557359

van Dijk, Korine; Parker, Jack; Tong, C Maya; Ham, Lisanne; Lie, Jessica T; Groeneveld-van Beek, Esther A; Melles, Gerrit R J

2014-04-01

367

Links between Plant and Rhizoplane Bacterial Communities in Grassland Soils, Characterized Using Molecular Techniques  

Microsoft Academic Search

Molecular analysis of grassland rhizosphere soil has demonstrated complex and diverse bacterial commu- nities, with resultant difficulties in detecting links between plant and bacterial communities. These studies have, however, analyzed \\

Naoise Nunan; Timothy J. Daniell; Brajesh K. Singh; Artemis Papert; James W. McNicol; James I. Prosser

2005-01-01

368

The use of molecular techniques for the diagnosis and epidemiologic study of sexually transmitted infections  

Microsoft Academic Search

Molecular diagnostic tests are more sensitive and, in many cases, more specific than conventional laboratory methods for the\\u000a detection of sexually transmitted infections. Here, we review recently developed molecular methods for the diagnosis and subtyping\\u000a of the most common sexually transmitted infections: infections caused by Chlamydia trachomatis, Neisseria gonorrhoeae, human papillomavirus, Trichomonas vaginalis, and the agents of genital ulcer disease

Carolyn M. Black; Stephen A. Morse

2000-01-01

369

Advanced space power requirements and techniques. Task 1: Mission projections and requirements. Volume 1: Technical report  

NASA Technical Reports Server (NTRS)

The objectives of this study were to: (1) develop projections of the NASA, DoD, and civil space power requirements for the 1980-1995 time period; (2) identify specific areas of application and space power subsystem type needs for each prospective user; (3) document the supporting and historical base, including relevant cost related measures of performance; and (4) quantify the benefits of specific technology projection advancements. The initial scope of the study included: (1) construction of likely models for NASA, DoD, and civil space systems; (2) generation of a number of future scenarios; (3) extraction of time phased technology requirements based on the scenarios; and (4) cost/benefit analyses of some of the technologies identified.

Wolfe, M. G.

1978-01-01

370

Cervical brachytherapy technique for locally advanced carcinoma of the cervix in a patient with septate uterus  

PubMed Central

Purpose To describe an approach to cervical brachytherapy in a patient with congenital septate uterus and locally advanced cervical carcinoma. Material and methods The patient is a 34-year-old female with septate uterus presenting with pelvic pain. Workup demonstrated a stage IIB cervical adenocarcinoma with imaging evidence of an involved right external iliac lymph node. The patient received whole pelvic radiation, with concurrent weekly cisplatin (40 mg/m2), to a dose of 45 Gy in 25 fractions followed by a parametrial boost of 5.4 Gy and an additional nodal boost of 9 Gy. Results The patient was initiated on cervical brachytherapy following fraction 23 of pelvic radiation. To conform to her septated uterus, a Rotte-Y tandem was used. Additionally, 2 CT-compatible ovoids were placed in the vaginal apex to enhance dose distribution and coverage of the target volume. Each fraction of brachytherapy was performed with CT-based planning. A high-risk clinical target volume (HR-CTV) and normal structures were defined and constrained per American Brachytherapy Society (ABS) and Groupe Européen de Curiethérapie/European Society for Therapeutic Radiology and Oncology (GEC-ESTRO) guidelines. The brachytherapy dose was 27.5 Gy in 5 fractions of 5.5 Gy each, prescribed to the HR-CTV. Conclusions Herein, we report the first documented case of cervical brachytherapy in a patient with septate uterus and locally advanced cervical carcinoma. Using CT-guided planning, in conjunction with the ABS and GEC-ESTRO guidelines, the patient was effectively treated with adapted cervical brachytherapy, meeting criteria for HR-CTV coverage and normal tissue tolerances. PMID:24790625

Wallace, Charlie; Gondi, Vinai; Das, Rupak; Straub, Margaret; Al-Niaimi, Ahmed; Applegate, Glenn; Bradley, Kristin A.

2014-01-01

371

Advanced sensing and control techniques to facilitate semi-autonomous decommissioning. 1998 annual progress report  

SciTech Connect

'This research is intended to advance the technology of semi-autonomous teleoperated robotics as applied to Decontamination and Decommissioning (D and D) tasks. Specifically, research leading to a prototype dual-manipulator mobile work cell is underway. This cell is supported and enhanced by computer vision, virtual reality and advanced robotics technology. This report summarizes work after approximately 1.5 years of a 3-year project. The autonomous, non-contact creation of a virtual environment from an existing, real environment (virtualization) is an integral part of the workcell functionality. This requires that the virtual world be geometrically correct. To this end, the authors have encountered severe sensitivity in quadric estimation. As a result, alternative procedures for geometric rendering, iterative correction approaches, new calibration methods and associated hardware, and calibration quality examination software have been developed. Following geometric rendering, the authors have focused on improving the color and texture recognition components of the system. In particular, the authors have moved beyond first-order illumination modeling to include higher order diffuse effects. This allows us to combine the surface geometric information, obtained from the laser projection and surface recognition components of the system, with a stereo camera image. Low-level controllers for Puma 560 robotic arms were designed and implemented using QNX. The resulting QNX/PC based low-level robot control system is called QRobot. A high-level trajectory generator and application programming interface (API) as well as a new, flexible robot control API was required. Force/torque sensors and interface hardware have been identified and ordered. A simple 3-D OpenGL-based graphical Puma 560 robot simulator was developed and interfaced with ARCL and RCCL to assist in the development of robot motion programs.'

Schalkoff, R.J.; Geist, R.M.; Dawson, D.M.

1998-06-01

372

Advanced Time-domain Calibrations and Data-reductionTechniques with HST/COS.  

NASA Astrophysics Data System (ADS)

The Hubble Space Telescope/Cosmic Origins Spectrograph (HST/COS) detectors have a time-tag mode of observation in which the arrival time of each photon is recorded individually. Although the COS calibration pipeline (CalCOS) makes use of this capability in many aspects of routine processing, there remains a number other ways that this information can be used to improve the calibration for specific science cases. This has led to the development of tools and techniques to perform additional calibrations that are not part of the standard data products output by CalCOS, but have been made available to the user. Here we demonstrate a few of these techniques including day/night filtering, extracting spectra on sub-exposure timescales, producing photometric light-curves, and performing additional dark-count screening.

Ely, Justin; Bostroem, K. Azalee; Debes, John H.; Hernandez, Svea; Hodge, Philip; Jedrzejewski, Robert I.; Lindsay, Kevin; Massa, Derck; Oliveira, Cristina M.; Penton, Steven V.; Proffitt, Charles R.; Roman-Duval, Julia; Sahnow, David J.; Sana, Hugues; Sonnentrucker, Paule; Taylor, Joanna M.

2014-06-01

373

Characterization of failure modes in deep UV and deep green LEDs utilizing advanced semiconductor localization techniques.  

SciTech Connect

We present the results of a two-year early career LDRD that focused on defect localization in deep green and deep ultraviolet (UV) light-emitting diodes (LEDs). We describe the laser-based techniques (TIVA/LIVA) used to localize the defects and interpret data acquired. We also describe a defect screening method based on a quick electrical measurement to determine whether defects should be present in the LEDs. We then describe the stress conditions that caused the devices to fail and how the TIVA/LIVA techniques were used to monitor the defect signals as the devices degraded and failed. We also describe the correlation between the initial defects and final degraded or failed state of the devices. Finally we show characterization results of the devices in the failed conditions and present preliminary theories as to why the devices failed for both the InGaN (green) and AlGaN (UV) LEDs.

Tangyunyong, Paiboon; Miller, Mary A.; Cole, Edward Isaac, Jr.

2012-03-01

374

POC-SCALE TESTING OF AN ADVANCED FINE COAL DEWATERING EQUIPMENT/TECHNIQUE  

SciTech Connect

The main objective of the proposed program is to evaluate a novel surface modification technique, which utilizes the synergistic effect of metal ions-surfactant combination, for dewatering of ultra-fine clean coal on a proof-of-concept scale of 1 to 2 tph. The novel surface modification technique developed at the UKCAER will be evaluated using vacuum, centrifuge, and hyperbaric filtration equipment. Dewatering tests will be conducted using the fine clean-coal froth produced by the column flotation units at the Powell Mountain Coal Company, Mayflower Preparation Plant in St. Charles, Virginia. The POC-scale studies will be conducted on two different types of clean coal, namely, high-sulfur and low-sulfur clean coal. The Mayflower Plant processes coals from five different seams, thus the dewatering studies results could be generalized for most of the bituminous coals.

B.K. PAREKH; D. TAO; J.G. GROPPO

1998-02-03

375

Advanced state of charge measurement technique for silver-zinc batteries  

Microsoft Academic Search

AlliedSignal has developed innovative battery analysis and charging technologies for lead acid, nickel cadmium, and silver-zinc battery families, under the Navy's new technology development initiative. Commercial-off-the-shelf (COTS) equipment has been used to develop and implement technologies to meet the growing analysis and maintenance needs of secondary batteries. One highlight of the capabilities developed under this program, is a technique for

H. Singh; T. Palanisamy; P. Rudai; S. Hoenig; D. Mains; W. R. Johnson

2000-01-01

376

Advances in instrumentation in liquid chromatography–mass spectrometry and related liquid-introduction techniques  

Microsoft Academic Search

In the past few years, the instrumental developments in the field of combined liquid chromatography–mass spectrometry (LC–MS) and related liquid-introduction techniques has been extremely fast. Soon after the demonstration of the ability to obtain multiply-charged ions from proteins by electrospray ionization, a major impetus was given to the field. Numerous LC–MS systems based on atmospheric-pressure ionization sources have now been

W. M. A Niessen

1998-01-01

377

Travels through the time-frequency zone: advanced Doppler ultrasound processing techniques  

Microsoft Academic Search

Doppler ultrasound echoes from cardiac structures is rich in detail and highly nonstationary. The goal of time frequency analysis is to extract features from these echo signals for high confidence visual and machine classification of cardiovascular condition. Presented are side-by-side comparisons of numerous time-frequency representations (TFRs) of Doppler ultrasound data. The techniques illustrated include the short-time Fourier transform, the wavelet

L. Marple; T. Brotherton; R. Barton; E. Lugo; D. Jones

1993-01-01

378

Development of urban area geospatial information products from high resolution satellite imagery using advanced image analysis techniques  

NASA Astrophysics Data System (ADS)

The latest generation of commercial satellite imaging sensors have a number of characteristics (e.g. high spatial resolution, multispectral bands, and quick revisit time), that make them ideal data sources for a variety of urban area applications. The goal of this doctoral research was to develop advanced automated and semi-automated image analysis and classification techniques for the extraction of urban area geospatial information products from commercial high-resolution satellite imagery. We developed two semi-automated urban land cover classification approaches, as well as fully automated techniques for road network and 2-D building footprint extraction. By utilizing fully automated feature extraction techniques for training data generation, a self-supervised classification approach was also developed. The self-supervised classifier is significantly more accurate than traditional classification approaches, and unlike traditional approaches it is fully automated. The development of automated and semi-automated techniques for generation of urban geospatial information products is of high importance not only for the many applications where they can be used but also because the large volume of data collected by these sensors exceeds the human capacity of trained image specialists to analyze. In addition, many applications, especially those for the military and intelligence communities, require near real time exploitation of the image data.

Shackelford, Aaron K.

379

Advanced three-dimensional electron microscopy techniques in the quest for better structural and functional materials  

NASA Astrophysics Data System (ADS)

After a short review of electron tomography techniques for materials science, this overview will cover some recent results on different shape memory and nanostructured metallic systems obtained by various three-dimensional (3D) electron imaging techniques. In binary Ni-Ti, the 3D morphology and distribution of Ni4Ti3 precipitates are investigated by using FIB/SEM slice-and-view yielding 3D data stacks. Different quantification techniques will be presented including the principal ellipsoid for a given precipitate, shape classification following a Zingg scheme, particle distribution function, distance transform and water penetration. The latter is a novel approach to quantifying the expected matrix transformation in between the precipitates. The different samples investigated include a single crystal annealed with and without compression yielding layered and autocatalytic precipitation, respectively, and a polycrystal revealing different densities and sizes of the precipitates resulting in a multistage transformation process. Electron tomography was used to understand the interaction between focused ion beam-induced Frank loops and long dislocation structures in nanobeams of Al exhibiting special mechanical behaviour measured by on-chip deposition. Atomic resolution electron tomography is demonstrated on Ag nanoparticles in an Al matrix.

Schryvers, D.; Cao, S.; Tirry, W.; Idrissi, H.; Van Aert, S.

2013-02-01

380

Recent Advances of Portable Multi-Sensor Technique of Volcanic Plume Measurement  

NASA Astrophysics Data System (ADS)

A technique has been developed to estimate chemical composition volcanic gases based on the measurement of volcanic plumes at distance from a source vent by the use of a portable multi-sensor system consisting a humidity sensor, an SO2 electrochemical sensor and a CO2 IR analyzer (Shinohara, 2005). Since volcanic plume is a mixture of the atmosphere and volcanic gases, the volcanic gas composition can be estimated by subtracting the atmospheric background from the plume data. This technique enabled us to estimate concentration ratios of major volcanic gas species (i.e., H2O, CO2 and SO2) without any complicated chemical analyses even for gases emitted from an inaccessible open vent. Since the portable multi-sensor system was light (~ 5 kg) and small enough to carry in a medium size backpack, we could apply this technique to measure volcanic plumes at summit of various volcanoes including those which require us a tough climbing, such as Villarrica volcano, Chile. We further improved the sensor system and the measurements techniques, including application of LI-840 IR H2O and CO2 analyzer, H2S electrochemical sensor and H2 semi-conductor sensor. Application of the new LI-840 analyzer enabled us to measure H2O concentration in the plume with similar response time with CO2 concentration. The H2S electrochemical sensor of Komyo Co. has a chemical filter to removed SO2 to achieve a low sensitivity (0.1%) to SO2, and we can measure a high SO2/H2S ratio up to 1000. The semi-conductor sensor can measure H2 concentration in the range from the background level in the atmosphere (~0.5 ppm) to ~50 ppm. Response of the H2 sensor is slower (90% response time = ~90 sec) than other sensors in particular in low concentration range, and the measurement is still semi-quantitative with errors up to ±50%. The H2/H2O ratios are quite variable in volcanic gases ranging from less than 10-5 up to 10-1, and the ratio is largely controlled by temperature and pressure condition of the internal equilibrium. In particular, we can calculate the equilibrium condition for the reaction (SO2 + 3H2 = 2H2O + H2S) based on the results of the plume measurements by the portable multi-sensor technique.

Shinohara, H.

2005-12-01

381

Soft X-Ray Microscopy and Spectroscopy at the Molecular Environmental Science Beamline at the Advanced Light Source  

SciTech Connect

We present examples of the application of synchrotron-based spectroscopies and microscopies to environmentally-relevant samples. The experiments were performed at the Molecular Environmental Science beamline (11.0.2) at the Advanced Light Source, Lawrence Berkeley National Laboratory. Examples range from the study of water monolayers on Pt(111) single crystal surfaces using X-ray emission spectroscopy and the examination of alkali halide solution/water vapor interfaces using ambient pressure photoemission spectroscopy, to the investigation of actinides, river-water biofilms, Al-containing colloids and mineral-bacteria suspensions using scanning transmission X-ray spectromicroscopy. The results of our experiments show that spectroscopy and microscopy in the soft X-ray energy range are excellent tools for the investigation of environmentally relevant samples under realistic conditions, i.e. with water or water vapor present at ambient temperature.

Bluhm, Hendrik; Andersson, Klas J.; Araki, Tohru; Benzerara, Karim; Brown, Gordon E.; Dynes, Jay J.; Ghosal, Sutapa; Gilles, Mary K.; Hansen, Hans C.; Hemminger, J. C.; Hitchcock, Adam P.; Ketteler, Guido; Kilcoyne, Arthur L.; Kneedler, Eric M.; Lawrence, John R.; Leppard, Gary G.; Majzlam, Juraj; Mun, B. S.; Myneni, Satish C.; Nilsson, Anders R.; Ogasawara, Hirohito; Ogletree, D. F.; Pecher, Klaus H.; Salmeron, Miquel B.; Shuh, David K.; Tonner, Brian; Tyliszczak, Tolek; Warwick, Tony; Yoon, T. H.

2006-02-01

382

Advanced NMR-based techniques for pore structure analysis of coal  

SciTech Connect

One of the main problems in coal utilization is the inability to properly characterize its complex pore structure. Coals typically have micro/ultra-micro pores but they also exhibit meso and macroporosity. Conventional pore size techniques (adsorption/condensation, mercury porosimetry) are limited because of this broad pore size range, microporosity, reactive nature of coal, samples must be completely dried, and network/percolation effects. Small angle scattering is limited because it probes both open and closed pores. Although one would not expect any single technique to provide a satisfactory description of a coal's structure, it is apparent that better techniques are necessary. We believe that measurement of the NMR parameters of various gas phase and adsorbed phase NMR active probes can provide the resolution to this problem. We will investigate the dependence of the common NMR parameters such as chemical shifts and relaxation times of several different nuclei and compounds on the pore structure of model microporous solids, carbons, and coals. In particular, we will study the interaction between several small molecules and the pore surfaces in coals. These molecules have been selected for their chemical and physical properties. A special NMR probe will be constructed which will allow the concurrent measurement of NMR properties and adsorption uptake at a variety of temperatures. All samples will be subjected to a suite of conventional'' pore structure analyses. These include nitrogen adsorption at 77 K with BET analysis, CO[sub 2] and CH[sub 4] adsorption at 273 K with D-R (Dubinin-Radushkevich) analysis, helium pycnometry, and small angle X-ray scattering as well as gas diffusion measurements.

Smith, D.M.

1992-01-01

383

Recent advances in chiral separation of amino acids using capillary electromigration techniques.  

PubMed

This review highlights recent progresses in the chiral recognition and separation of amino acid enantiomers obtained by capillary electromigration techniques, using different chiral selectors and especially cyclodextrins, covering the literature published from January 2010 to March 2014. Sections are dedicated to the use of derivatization reagents and to the possibility to enantioseparate underivatized amino acids by using either ligand exchange capillary electrophoresis (LECE) and capillary electrophoresis (CE) coupled on line with mass spectrometry. A short insight on frontier nanomaterials is also given. PMID:25171947

Giuffrida, Alessandro; Maccarrone, Giuseppe; Cucinotta, Vincenzo; Orlandini, Serena; Contino, Annalinda

2014-10-10

384

Development of techniques for advanced optical contamination measurement with internal reflection spectroscopy, phase 1, volume 1  

NASA Technical Reports Server (NTRS)

The feasibility of monitoring volatile contaminants in a large space simulation chamber using techniques of internal reflection spectroscopy was demonstrated analytically and experimentally. The infrared spectral region was selected as the operational spectral range in order to provide unique identification of the contaminants along with sufficient sensitivity to detect trace contaminant concentrations. It was determined theoretically that a monolayer of the contaminants could be detected and identified using optimized experimental procedures. This ability was verified experimentally. Procedures were developed to correct the attenuated total reflectance spectra for thick sample distortion. However, by using two different element designs the need for such correction can be avoided.

Hayes, J. D.

1972-01-01

385

Advanced definition study for the determination of atmospheric ozone using the satellite eclipse technique  

NASA Technical Reports Server (NTRS)

A study was made to evaluate the potential for remote ground-based measurement of upper atmospheric ozone by determining the absorption ratio of selected narrow bands of sunlight as reflected by satellites while passing into eclipse, using the NASA Mobile Satellite Photometric Observatory (MOSPO). Equipment modifications to provide optimum performance were analyzed and recommendations were made for improvements to the system to accomplish this. These included new sensor tubes, pulse counting detection circuitry, filters, beam splitters and associated optical revision, along with an automatic tracking capability plus corresponding operational techniques which should extend the overall measurement capability to include use of satellites down to 5th magnitude.

Emmons, R.; Preski, R. J.; Kierstead, F. H., Jr.; Doll, F. C.; Wight, D. T.; Romick, D. C.

1973-01-01

386

Advanced Failure Determination Measurement Techniques Used in Thermal Fatigue Life Testing of Electronic Packaging  

NASA Technical Reports Server (NTRS)

Thermal fatigue life testing of various electronic packaging technologies is being performed by the Reliability Technology Group at the Jet Propulsion Laboratory. These testing efforts are in progress to improve uderstanding of the reliability issues associated with low volume packaging technologies for space applications and to develop qualification and acceptance approaches for these technologies. The work described here outlines the electrical failure detection techniques used during testing by documenting the circuits and components used to make these measurements, the sensitivity of the measurements, and the applicability of each specific measurement.

Wallace, A. P.; Cornford, S. L.; Gross, M. A.

1996-01-01

387

Advanced technologies for the improvement of spray application techniques in spanish viticulture: an overview.  

PubMed

Spraying techniques have been undergoing continuous evolution in recent decades. This paper presents part of the research work carried out in Spain in the field of sensors for characterizing vineyard canopies and monitoring spray drift in order to improve vineyard spraying and make it more sustainable. Some methods and geostatistical procedures for mapping vineyard parameters are proposed, and the development of a variable rate sprayer is described. All these technologies are interesting in terms of adjusting the amount of pesticides applied to the target canopy. PMID:24451462

Gil, Emilio; Arnó, Jaume; Llorens, Jordi; Sanz, Ricardo; Llop, Jordi; Rosell-Polo, Joan R; Gallart, Montserrat; Escolà, Alexandre

2014-01-01

388

Advanced Technologies for the Improvement of Spray Application Techniques in Spanish Viticulture: An Overview  

PubMed Central

Spraying techniques have been undergoing continuous evolution in recent decades. This paper presents part of the research work carried out in Spain in the field of sensors for characterizing vineyard canopies and monitoring spray drift in order to improve vineyard spraying and make it more sustainable. Some methods and geostatistical procedures for mapping vineyard parameters are proposed, and the development of a variable rate sprayer is described. All these technologies are interesting in terms of adjusting the amount of pesticides applied to the target canopy. PMID:24451462

Gil, Emilio; Arnó, Jaume; Llorens, Jordi; Sanz, Ricardo; Llop, Jordi; Rosell-Polo, Joan R.; Gallart, Montserrat; Escolà, Alexandre

2014-01-01

389

Molecular diagnostics in transplantation  

Microsoft Academic Search

The past few decades are characterized by an explosive evolution of genetics and molecular cell biology. Advances in chemistry and engineering have enabled increased data throughput, permitting the study of complete sets of molecules with increasing speed and accuracy using techniques such as genomics, transcriptomics, proteomics, and metabolomics. Prediction of long-term outcomes in transplantation is hampered by the absence of

Minnie M. Sarwal; Maarten Naesens

2010-01-01

390

Multispectral indices and advanced classification techniques to detect percent residue cover over agricultural crops using Landsat data  

NASA Astrophysics Data System (ADS)

Detecting and quantifying crop residue cover on agricultural fields is essential in identifying conservation tillage practices and estimating carbon sequestration, both of which are important goals within the Agricultural Policy Framework of Agriculture and Agri-Food Canada. Crop residue is traditionally measured using ground survey techniques such as the line-transect method or visual (drive-by) assessment but these techniques are tedious, time-consuming and subjective. With the increased number of advanced earth observation satellites, remote sensing has now become a viable option for mapping agricultural land management practices and percent crop residue cover. A wide variety of indices such as the Normalized Difference Index (NDI) and the Modified Soil Adjusted Crop Residue Index (MSACRI) were developed using multispectral data for this purpose but results have been mixed. Advanced classification techniques including linear spectral mixture analysis (SMA) and spectral angle mapper (SAM) provide an alternative to derive percent crop residue cover. Landsat-7 SLC-Off data were acquired over an agricultural study site in Eastern Ontario on May 25 2005. Simultaneous ground data were collected to characterize residue type, position, direction and percent cover. NDI, MSACRI, SMA and SAM were all computed and used to derive percent crop residue cover information. Preliminary results indicate that the SMA model predicts percent crop residue cover over agricultural fields with the most success, especially over fields of corn residue with an R2 value of 0.85 (RMSE of 12.46 and D of 0.99). However, further investigation is needed where residue models are validated against a larger dataset with greater variability in percent crop residue cover.

Pacheco, Anna; McNairn, Heather; Smith, Anne M.

2006-08-01

391

Advanced x-ray spectrometric techniques for characterization of nuclear materials: An overview of recent laboratory activities  

NASA Astrophysics Data System (ADS)

Advancements in x-ray spectrometric techniques at different stages have made this technique suitable for characterization of nuclear materials with respect to trace/major element determinations and compositional uniformity studies. The two important features of total reflection x-ray fluorescence spectrometry: 1) requirement of very small amount of sample in ng level 2) multielement analytical capability, in addition to other features, make this technique very much suitable to nuclear materials characterization as most of the nuclear materials are radioactive and the radioactive waste generated and radiation hazards to the operator are minimum when such low amount of sample is used. Similarly advanced features of energy dispersive x-ray fluorescence e.g. better geometry for high flux, reduction in background due to application of radiation filters have made the measurements of samples sealed inside thin alkathene/PVC covers possible with good sensitivity. This approach avoids putting the instrument inside a glove box for measuring radioactive samples and makes the operation/maintenance of the instrument and analysis of the samples possible in easy and fast manner. This approach has been used for major element determinations in mixed uranium-plutonium samples. Similarly ?-XRF with brilliant and micro-focused excitation sources can be used for compositional uniformity study of reactor fuel pellets. A ?-XRF study using synchrotron light source has been made to assess the compositional uniformity of mixed uranium-thorium oxide pellets produced by different processes. This approach is simple as it does not involve any sample preparation and is non-destructive. A brief summary of such activities carried out in our laboratory in past as well as ongoing and planned for the future have been discussed in the present manuscript.

Misra, N. L.

2014-11-01

392

Advances in Immuno–Positron Emission Tomography: Antibodies for Molecular Imaging in Oncology  

PubMed Central

Identification of cancer cell–surface biomarkers and advances in antibody engineering have led to a sharp increase in the development of therapeutic antibodies. These same advances have led to a new generation of radiolabeled antibodies and antibody fragments that can be used as cancer-specific imaging agents, allowing quantitative imaging of cell-surface protein expression in vivo. Immuno–positron emission tomography (immunoPET) imaging with intact antibodies has shown success clinically in diagnosing and staging cancer. Engineered antibody fragments, such as diabodies, minibodies, and single-chain Fv (scFv) –Fc, have been successfully employed for immunoPET imaging of cancer cell–surface biomarkers in preclinical models and are poised to bring same-day imaging into clinical development. ImmunoPET can potentially provide a noninvasive approach for obtaining target-specific information useful for titrating doses for radioimmunotherapy, for patient risk stratification and selection of targeted therapies, for evaluating response to therapy, and for predicting adverse effects, thus contributing to the ongoing development of personalized cancer treatment. PMID:22987087

Knowles, Scott M.; Wu, Anna M.

2012-01-01

393

Advanced passivation techniques for Si solar cells with high-? dielectric materials  

NASA Astrophysics Data System (ADS)

Electronic recombination losses at the wafer surface significantly reduce the efficiency of Si solar cells. Surface passivation using a suitable thin dielectric layer can minimize the recombination losses. Herein, advanced passivation using simple materials (Al2O3, HfO2) and their compounds H(Hf)A(Al)O deposited by atomic layer deposition (ALD) was investigated. The chemical composition of Hf and Al oxide films were determined by X-ray photoelectron spectroscopy (XPS). The XPS depth profiles exhibit continuous uniform dense layers. The ALD-Al2O3 film has been found to provide negative fixed charge (-6.4 × 1011 cm-2), whereas HfO2 film provides positive fixed charge (3.2 × 1012 cm-2). The effective lifetimes can be improved after oxygen gas annealing for 1 min. I-V characteristics of Si solar cells with high-? dielectric materials as passivation layers indicate that the performance is significantly improved, and ALD-HfO2 film would provide better passivation properties than that of the ALD-Al2O3 film in this research work.

Geng, Huijuan; Lin, Tingjui; Letha, Ayra Jagadhamma; Hwang, Huey-Liang; Kyznetsov, Fedor A.; Smirnova, Tamara P.; Saraev, Andrey A.; Kaichev, Vasily V.

2014-09-01

394

Non-contact ultrasonic technique for rapid and advanced analysis of fibrous materials  

NASA Astrophysics Data System (ADS)

Fibrous ensembles are, typically, multi-scale flexible assemblies with unique physical and rheological properties, unlike continuum materials. Macroscopic behaviors of these materials are greatly the result of non-linear interactions at the micro levels. These micro-scale interactions can be assessed by capturing the material behavior under low mechanical stress conditions. While ultrasonic based non-destructive testing was suitably implemented for continuum materials, their application to fibrous structures was limited primarily due to the inherent structural arrangements of these unique assemblies. Discontinuities, non-uniform orientations and multi-phase components make these ensembles difficult to study using the existing scan-based methods. This work presents a novel rapid and advanced analysis tool for complex fibrous systems using a noncontact air-coupled ultrasonic system. Five characteristic features of ultrasound signals transmitted through fibrous structures were studied, i.e., dampness in signal flight, signal velocity, power spectral density, signal power and rate of amplitude attenuation. Analysis of these features under two different acoustic frequencies, 500 kHz and 1 MHz, allowed us to study the componentized behavior of these materials for three of the key mechanical properties including bending rigidity, shear rigidity and low stress tensile stress. A material response index (MRI) was also derived using the signal features.

Periyaswamy, T.; Lerch, T. P.; Balasubramanian, K.

2012-05-01

395

Glycoproteomics on the rise: established methods, advanced techniques, sophisticated biological applications.  

PubMed

Glycosylation is the most complex form of protein PTMs. Affected proteins may carry dozens of glycosylation sites with tens to hundreds of glycan residues attached to every site. Glycosylated proteins have many important functions in biology, from cellular to organismal levels, being involved in cell-cell signaling, cell adhesion, immune response, host-pathogen interactions, and development and growth. Glycosylation, however, expands the biological functional diversity of proteins at the expense of a tremendous increase in structural heterogeneity. Aberrant glycosylation of cell surface proteins, as well as their detectable fingerprint in plasma samples, has been associated with cancer, inflammatory and degenerative diseases, and congenital disorders of glycosylation. Therefore, there are on-going efforts directed toward developing new technologies and approaches for glycan sequencing and high-throughput analysis of glycosylated proteins in complex samples with simultaneous characterization of both the protein and glycan moieties. This work is aimed primarily at pinpointing the challenges associated with the large-scale analysis of glycoproteins and the latest developments in glycoproteomic research, with focus on recent advancements (2011-2012) in microcolumn separations and MS detection. PMID:23161435

Lazar, Iulia M; Lee, Wooram; Lazar, Alexandru C

2013-01-01

396

Molecular layer deposition of functional thin films for advanced lithographic patterning.  

PubMed

Photoresist materials comprise one of the main challenges faced by lithography to meet the requirements of electronic device size scaling. Here we report for the first time the use of molecular layer deposition (MLD) to produce photoresist materials with controllable placement of functional moieties. Polyurea resists films are deposited by MLD using urea coupling reactions between 1,4-phenylene diisocyanate (PDIC) and ethylenediamine (ED) or 2,2'-(propane-2,2-diylbis(oxy))diethanamine (PDDE) monomers in a layer-by-layer fashion with a linear growth rate, allowing acid-labile groups to be incorporated into the film at well-controlled positions. The films are deposited with stoichiometric compositions and have highly uniform surface morphology as investigated using atomic force microscopy. We show that acid treatment can cleave the backbone of the polyurea film at positions where the acid-labile groups are embedded. We further show that after soaking the polyurea film with photoacid generator (PAG), it acts as a photoresist material and we present several UV patterning demonstrations. This approach presents a new way to make molecularly designed resist films for lithography. PMID:21302918

Zhou, Han; Bent, Stacey F

2011-02-01

397

Applying advanced surface analysis techniques to small defect characterization on EUV ML blanks  

NASA Astrophysics Data System (ADS)

Developing capability in detection, review, and characterization of sub-100 nm defects on EUV multilayer blanks has become critical in enabling the defect root-cause analysis and the eventual elimination of all defects. We have developed a functional method to apply surface analytical techniques (AES, SEM, EDX, and AFM) to characterize individual defects on EUV multilayer blanks. Optical defect inspection is first done with the Lasertec M1350 which does defect scanning, mapping, image review, and fiducial marking. A defect map is then used to navigate defect search on other tools. Those surface analysis techniques and tools are complementary in uncovering defect elemental as well as morphological data. Our experimental results demonstrated that Auger spectroscopy provides the best lateral resolution and surface-specific elemental information. It is capable of detecting and analyzing compositions of sub-100nm defects, either embedded in or on the surface of the multilayer blanks. The composition defect data serve as the crucial "fingerprints" of the blank fabrication process. SEM provides the morphological shape and size data, which are also critical in the identification of defects. AFM gives the precise defect height data, important for defect smoothing and printability analysis. The EDX/FIB tool provides capability of cross sections of embedded defects.

Shu, Emily Y.

2004-12-01

398

Journal of Cellular Biochemistry Supplement 39:194210 (2002) Advances in Molecular Labeling, High Throughput  

E-print Network

, California 2 Q3DM, Inc., San Diego, California 3 Department of Cell Biology, The Scripps Research Institute imaging techniques have the potential to impact cellular diagnostics for cancer screening, clinical for accelerating drug discovery. The goal of finally understanding all cellular components and behaviors

Gordon, Geoffrey J.

399

Advanced numerical modeling and hybridization techniques for third-generation infrared detector pixel arrays  

NASA Astrophysics Data System (ADS)

Infrared (IR) detectors are well established as a vital sensor technology for military, defense and commercial applications. Due to the expense and effort required to fabricate pixel arrays, it is imperative to develop numerical simulation models to perform predictive device simulations which assess device characteristics and design considerations. Towards this end, we have developed a robust three-dimensional (3D) numerical simulation model for IR detector pixel arrays. We used the finite-difference time-domain technique to compute the optical characteristics including the reflectance and the carrier generation rate in the device. Subsequently, we employ the finite element method to solve the drift-diffusion equations to compute the electrical characteristics including the I(V) characteristics, quantum efficiency, crosstalk and modulation transfer function. We use our 3D numerical model to study a new class of detector based on the nBn-architecture. This detector is a unipolar unity-gain barrier device consisting of a narrow-gap absorber layer, a wide-gap barrier layer, and a narrow-gap collector layer. We use our model to study the underlying physics of these devices and to explain the anomalously long lateral collection lengths for photocarriers measured experimentally. Next, we investigate the crosstalk in HgCdTe photovoltaic pixel arrays employing a photon-trapping (PT) structure realized with a periodic array of pillars intended to provide broadband operation. The PT region drastically reduces the crosstalk; making the use of the PT structures not only useful to obtain broadband operation, but also desirable for reducing crosstalk, especially in small pitch detector arrays. Then, the power and flexibility of the nBn architecture is coupled with a PT structure to engineer spectrally filtering detectors. Last, we developed a technique to reduce the cost of large-format, high performance HgCdTe detectors by nondestructively screen-testing detector arrays prior to their final hybridization onto expensive silicon read-out integrated circuit (ROIC) chips. The approach is to temporarily hybridize each candidate HgCdTe detector array to a standard reusable ROIC for complete screen testing. We tested the technique by temporarily hybridizing LPE grown HgCdTe test chips to fan-out boards and characterizing their performance.

Schuster, Jonathan

400

Advanced combination of laser and synchrotron techniques to study minerals at extreme conditions in the time-domain mode (Invited)  

NASA Astrophysics Data System (ADS)

Over the past two decades, high pressure research has made breakthrough progress in many fields of science mainly due to significant advances in development of both high pressure vessels (diamond anvil cell and large volume press) and high brilliance synchrotron based techniques, including high resolution x-ray micro-diffraction, x-ray spectroscopy (absorption, emission, resonance), micro-imaging, inelastic and nuclear resonance scattering. Combination of double-sided laser heating with synchrotron x-ray radiation has stimulated synthesis and investigation of new materials with unique composition and properties in-situ at high temperatures and high pressures in the diamond anvil cell. Equation of state, structure, phase transformations, element partitioning, electronic and optical properties of various minerals (single crystal, powder, nano-crystalline, amorphous solid and fluids) have been successfully studied at extreme conditions with help of the lasers and x-ray beams. Recent developments in pulse laser heating technique, including application of fiber lasers and flat top laser beam shaping optics, result in significant improvement in synthesis of new metastable materials with tuneable composition and properties controlled in-situ with high resolution x-ray and optical techniques in time-domain mode. To study elastic properties of opaque minerals in situ at high pressure and temperature we have combined laser ultrasonic with laser heating techniques. The shear and longitudinal wave velocities were measured for iron at pressures up to 60 GPa in the diamond anvil cell. The details and application of the synchrotron and optical techniques for studies unique physical and chemical properties of minerals in-situ at extreme conditions will be discussed on example of iron-bearing materials.

Prakapenka, V.; Zinin, P.; Goncharov, A.; Zhuravlev, K. K.; Tkachev, S. N.

2013-12-01

401

Moving from histological subtyping to molecular characterization: new treatment opportunities in advanced non-small-cell lung cancer.  

PubMed

Over the last 10 years, the systemic treatment of advanced non-small-cell lung cancer has progressively moved away from the 'one-size-fits-all' approach to histological subtyping. Currently, there is a progressive implementation of targeted therapies based on specific molecular characteristics such as the EGF receptor sensitizing mutations and the anaplastic lymphoma kinase rearrangements. Despite the availability of effective agents against these abnormalities, acquired resistance is still a major issue. A new generation of tyrosine kinase inhibitors for EGF receptor and anaplastic lymphoma kinase targeting acquired resistance mechanisms have been recently investigated. Several promising tyrosine kinase inhibitors that hit other targets are also in clinical development, including: rat sarcoma gene/MEK, BRAF1, PIK3A, c-mesenchymal-epithelial transition, c-ros oncogene 1, rearranged during transfection, human EGFR 2, FGFR, VEGFR, PDGFR and discoidin death receptor 2. Furthermore, new advances in immunology have been achieved through the discovery of vaccines and immune checkpoint pathways such as the cytotoxic T-lymphocyte-associated antigen-4, programmed cell death protein 1 and its ligands. PMID:25183305

Carnio, Simona; Novello, Silvia; Bironzo, Paolo; Scagliotti, Giorgio Vittorio

2014-12-01

402

Technical Needs for Prototypic Prognostic Technique Demonstration for Advanced Small Modular Reactor Passive Components  

SciTech Connect

This report identifies a number of requirements for prognostics health management of passive systems in AdvSMRs, documents technical gaps in establishing a prototypical prognostic methodology for this purpose, and describes a preliminary research plan for addressing these technical gaps. AdvSMRs span multiple concepts; therefore a technology- and design-neutral approach is taken, with the focus being on characteristics that are likely to be common to all or several AdvSMR concepts. An evaluation of available literature is used to identify proposed concepts for AdvSMRs along with likely operational characteristics. Available operating experience of advanced reactors is used in identifying passive components that may be subject to degradation, materials likely to be used for these components, and potential modes of degradation of these components. This information helps in assessing measurement needs for PHM systems, as well as defining functional requirements of PHM systems. An assessment of current state-of-the-art approaches to measurements, sensors and instrumentation, diagnostics and prognostics is also documented. This state-of-the-art evaluation, combined with the requirements, may be used to identify technical gaps and research needs in the development, evaluation, and deployment of PHM systems for AdvSMRs. A preliminary research plan to address high-priority research needs for the deployment of PHM systems to AdvSMRs is described, with the objective being the demonstration of prototypic prognostics technology for passive components in AdvSMRs. Greater efficiency in achieving this objective can be gained through judicious selection of materials and degradation modes that are relevant to proposed AdvSMR concepts, and for which significant knowledge already exists. These selections were made based on multiple constraints including the analysis performed in this document, ready access to laboratory-scale facilities for materials testing and measurement, and potential synergies with other national laboratory and university partners.

Meyer, Ryan M.; Coble, Jamie B.; Hirt, Evelyn H.; Ramuhalli, Pradeep; Mitchell, Mark R.; Wootan, David W.; Berglin, Eric J.; Bond, Leonard J.; Henager, Charles H.

2013-05-17

403

Molecular and Other Novel Advances in Treatment of Metastatic Epithelial and Medullary Thyroid Cancers  

PubMed Central

An understanding of the mutations of the proto-oncogenes and tumor suppressor genes that occur in thyroid cancers should eventually explain the diverse clinical characteristics of these tumors and also direct therapy. Some insights have already emerged in the last decade; some abnormalities in tumor genes are consistently associated with specific clinical and pathologic findings. These genetic abnormalities usually represent somatic mutations in tumors of follicular epithelial origin, as opposed to inherited mutations in medullary thyroid cancers of parafollicular C cells origin because most thyroid tumors are sporadic and not familial. This is different from the multiple endocrine neoplasia syndromes in which the primary tumorigenic gene mutations are inherited. This improved understanding of the molecular basis of these diseases has led to the development of novel targeted therapeutic approaches which will be discussed in this paper. PMID:20862373

Tai, David; Poon, Donald

2010-01-01

404

New advances in molecular mechanisms and emerging therapeutic targets in alcoholic liver diseases  

PubMed Central

Alcoholic liver disease is a major health problem in the United States and worldwide. Chronic alcohol consumption can cause steatosis, inflammation, fibrosis, cirrhosis and even liver cancer. Significant progress has been made to understand key events and molecular players for the onset and progression of alcoholic liver disease from both experimental and clinical alcohol studies. No successful treatments are currently available for treating alcoholic liver disease; therefore, development of novel pathophysiological-targeted therapies is urgently needed. This review summarizes the recent progress on animal models used to study alcoholic liver disease and the detrimental factors that contribute to alcoholic liver disease pathogenesis including miRNAs, S-adenosylmethionine, Zinc deficiency, cytosolic lipin-1?, IRF3-mediated apoptosis, RIP3-mediated necrosis and hepcidin. In addition, we summarize emerging adaptive protective effects induced by alcohol to attenuate alcohol-induced liver pathogenesis including FoxO3, IL-22, autophagy and nuclear lipin-1?.

Williams, Jessica A; Manley, Sharon; Ding, Wen-Xing

2014-01-01

405

Refinement of homology-based protein structures by molecular dynamics simulation techniques  

Microsoft Academic Search

The use of classical molecular dynamics simulations, performed in explicit water, for the refinement of structural models of proteins generated ab initio or based on homology has been investigated. The study involved a test set of 15 proteins that were previously used by Baker and coworkers to assess the efficiency of the ROSETTA method for ab initio protein structure prediction.

HAO FAN; ALAN E. MARK

2004-01-01

406

Molecular pathology in lung cancer: a guide to the techniques used in clinical practice.  

PubMed

Five year survival rates for lung cancer patients are poor; however the development of new therapeutic options, which benefit subsets of the population, offer hope of improvement. These novel therapies frequently rely upon the analysis of biomarkers in pathology samples; in lung cancer patients, testing is now routinely carried out to identify small mutations and chromosomal rearrangements in order to predict response to treatment. The recent increase in biomarker analyses in pathology samples has lead to the development of a new specialty, molecular pathology. The use of molecular pathology assays in clinical samples is largely under the control of the histopathologist; who is likely to be asked, as a minimum, to select tissue sections for molecular analysis and mark areas of H&E stained slides for macro or microdissection. Many histopathologists will also be involved in the sourcing and implementation of new assays. This review aims to provide a guide to some of the most commonly used molecular pathology methods - their advantages and their limitations. PMID:25130601

Walsh, Kathy; Wallace, William A

2014-12-01

407

Eigensolution techniques, their applications and Fisher?s information entropy of the Tietz–Wei diatomic molecular model  

NASA Astrophysics Data System (ADS)

In this study, the approximate analytical solutions of Schrödinger, Klein–Gordon and Dirac equations under the Tietz–Wei (TW) diatomic molecular potential are represented by using an approximation for the centrifugal term. We have applied three types of eigensolution techniques: the functional analysis approach, supersymmetry quantum mechanics and the asymptotic iteration method to solve the Klein–Gordon, Dirac and Schrödinger equations, respectively. The energy eigenvalues and the corresponding eigenfunctions for these three wave equations are obtained, and some numerical results and figures are reported. It has been shown that these techniques yielded exactly the same results. some expectation values of the TW diatomic molecular potential within the framework of the Hellmann–Feynman theorem have been presented. The probability distributions that characterize the quantum mechanical states of TW diatomic molecular potential are analyzed by means of complementary information measures of a probability distribution called Fisher?s information entropy. This distribution has been described in terms of Jacobi polynomials, whose characteristics are controlled by quantum numbers.

Falaye, B. J.; Oyewumi, K. J.; Ikhdair, S. M.; Hamzavi, M.

2014-11-01

408

March 1998 361MOLECULAR TECHNIQUES IN ECOLOGY Ecology, 79(2), 1998, pp. 361382  

E-print Network

[random amplified polymorphic DNA], and DNA sequencing) to an array of questions regarding individual for most taxa, although techniques based on nucleic acids (par- ticularly DNA sequencing and mitochondrial DNA RFLPs) are useful here as well. Recently developed nucleic acid techniques (e.g., VNTRs) can often

Snow, Allison A.

409

Comment on "Theory of the double-edge molecular technique for Doppler lidar wind measurement".  

PubMed

A theory of the double-edge technique for lidar measurement of wind speed Doppler shifts was recently presented by Flesia and Korb [Appl. Opt. 38, 432 (1999)]. It is shown here that the technique proposed by Flesia and Korb to achieve equal responsivity to aerosol and Rayleigh backscatter signals was previously conceived and demonstrated by another group. PMID:18337978

McKay, J A

2000-02-20

410

Advancement and application of gas chromatography isotope ratio mass spectrometry techniques for atmospheric trace gas analysis  

NASA Astrophysics Data System (ADS)

The use of gas chromatography isotope ratio mass spectrometry (GC-IRMS) for compound specific stable isotope analysis is an underutilized technique because of the complexity of the instrumentation and high analytical costs. However stable isotopic data, when coupled with concentration measurements, can provide additional information on a compounds production, transformation, loss, and cycling within the biosphere and atmosphere. A GC-IRMS system was developed to accurately and precisely measure delta13C values for numerous oxygenated volatile organic compounds having natural and anthropogenic sources. The OVOCs include methanol, ethanol, acetone, methyl ethyl ketone, 2-pentanone, and 3-pentanone. Guided by the requirements for analysis of trace components in air, the GC-IRMS system was developed with the goals of increasing sensitivity, reducing dead-volume and peak band broadening, optimizing combustion and water removal, and decreasing the split ratio to the IRMS. The technique relied on a two-stage preconcentration system, a low-volume capillary reactor and water trap, and a balanced reference gas delivery system. Measurements were performed on samples collected from two distinct sources (i.e. biogenic and vehicle emissions) and ambient air collected from downtown Miami and Everglades National Park. However, the instrumentation and the method have the capability to analyze a variety of source and ambient samples. The measured isotopic signatures that were obtained from source and ambient samples provide a new isotopic constraint for atmospheric chemists and can serve as a new way to evaluate their models and budgets for many OVOCs. In almost all cases, OVOCs emitted from fuel combustion were enriched in 13C when compared to the natural emissions of plants. This was particularly true for ethanol gas emitted in vehicle exhaust, which was observed to have a uniquely enriched isotopic signature that was attributed to ethanol's corn origin and use as an alternative fuel or fuel additive. Results from this effort show that ethanol's unique isotopic signature can be incorporated into air chemistry models for fingerprinting and source apportionment purposes and can be used as a stable isotopic tracer for biofuel inputs to the atmosphere on local to regional scales.

Giebel, Brian M.

411

Advanced InSAR techniques for the management and characterization of geothermal resources  

NASA Astrophysics Data System (ADS)

InSAR is a remote sensing tool that has applications in both geothermal exploitation and in the management of producing fields. The technique has developed rapidly in recent years and the most evolved algorithms, now capable of providing precise ground movement measurements with unprecedented spatial density over large areas, allow the monitoring of the effects of fluid injection and extraction on surface deformation and the detection of active faults. Multi-interferogram approaches have been used at several geothermal sites in different stages of development. SqueeSAR™, which represents the latest breakthrough in InSAR technology, provides a significant increase in the spatial density of measurement points by exploiting signal returns from both point-like and distributed scatterers. Furthermore, recent satellite radar sensors have a higher spatial resolution (down to 1 m), as well as a higher temporal frequency of image acquisitions (down to a few days). The coupling of the new algorithm with this new generation of satellites provides a valuable tool for monitoring the different phases of geothermal production and in support of the decision making process. Some examples from the US are presented here: the first case study involves the use of InSAR within a suite of tools for exploration of the San Emidio geothermal field in Nevada. This project aimed to develop geophysical techniques to identify and map large aperture fractures for the placement of new production/exploration wells. The second and third examples examine two zones in California: the Salton Sea area, where multi-interferogram InSAR provided an overview of surface deformation at a producing geothermal reservoir. Surface deformation in this area was complex, and the added detail provided insight into the interplay of tectonics and production activities. Additional InSAR studies have also been carried out at the Geysers field in order to evaluate the behavior of an Enhanced Geothermal System (EGS) in response to high rates of water injection, with a strong interest in researching induced seismicity and ground deformation. These studies, along with the continuing developments in radar satellite technology and in the field of InSAR, show considerable promise for the future monitoring of geothermal production facilities.

Bellotti, F.; Falorni, G.; Morgan, J.; Rucci, A.; Ferretti, A.

2012-04-01

412

Advanced flux-weakening techniques for surface-mounted permanent-magnet machine drives  

NASA Astrophysics Data System (ADS)

Surface-Mounted Permanent-Magnet Synchronous (SMPMS) machine drives have been considered thus far unsuitable for an efficient, wide-range flux weakening operation. This thesis will detail two novel schemes that provide stable and reliable operation over a wide range above the machine base speed, without dependence on machine parameters, usage of look-up tables or DC bus voltage measurements. Both techniques employ space vector modulation (SVM) with the option of smooth transition into six-step mode through the over-modulation range, maximizing the torque available. The first scheme ensures exact torque command tracking, whereas the second one intrinsically gives a steady state error in the flux weakening area. The second method, on the other hand, is computationally simpler, offers better transient response and the steady state torque error is not a critical feature if the torque control loop is an inner loop. The first method uses closed loop control of the phase voltage magnitude to generate magnetizing current reference for the flux-weakening operation. The second approach detects the steady-state error in the torque current component regulation, and then uses the error