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1

Advanced techniques for constrained internal coordinate molecular dynamics.  

PubMed

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 to make the CICMD method robust and widely usable. In this article, we have designed a new framework for (1) initializing velocities for nonindependent 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 article, 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 molecular dynamics 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

2013-01-23

2

Advanced radiation measurement techniques in diagnostic radiology and molecular imaging.  

PubMed

This paper reports some technological advances recently achieved in the fields of micro-CT and small animal PET instrumentation. It highlights a balance between image-quality improvement and dose reduction. Most of the recent accomplishments in these fields are due to the use of novel imaging sensors such as CMOS-based X-ray detectors and silicon photomultipliers (SiPM). Some of the research projects carried out at the University of Pisa for the development of such advanced radiation imaging technology are also described. PMID:18757466

Del Guerra, Alberto; Belcari, Nicola; Llacer, Gabriela Llosa; Marcatili, Sara; Moehrs, Sascha; Panetta, Daniele

2008-08-29

3

Recent advances in molecular techniques to study microbial communities in food-associated matrices and processes.  

PubMed

In the last two decades major changes have occurred in how microbial ecologists study microbial communities. Limitations associated with traditional culture-based methods have pushed for the development of culture-independent techniques, which are primarily based on the analysis of nucleic acids. These methods are now increasingly applied in food microbiology as well. This review presents an overview of current community profiling techniques with their (potential) applications in food and food-related ecosystems. We critically assessed both the power and limitations of these techniques and present recent advances in the field of food microbiology attained by their application. It is unlikely that a single approach will be universally applicable for analyzing microbial communities in unknown matrices. However, when screening samples for well-defined species or functions, techniques such as DNA arrays and real-time PCR have the potential to overtake current culture-based methods. Most importantly, molecular methods will allow us to surpass our current culturing limitations, thus revealing the extent and importance of the 'non-culturable' microbial flora that occurs in food matrices and production. PMID:18620966

Justé, A; Thomma, B P H J; Lievens, B

2008-05-03

4

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

5

Exploration of advanced characterization techniques for molecular composites. Final report, February 1984-January 1985  

SciTech Connect

The techniques of solid-state nuclear magnetic resonance, fluorescence spectroscopy, electron-spin resonance, and x-ray diffraction were applied to characterize aspects of the solid-state structures of rigid-rod polymers and their blends with flexible polymers. NMR and fluorescence spectroscopies were used to investigate the degree to which the rigid rod - flexible polymers blends exist as phase-separated systems. It was found that these materials form primarily phase-segregated structures, a condition that limits the reinforcing potential of rigid rod polymers in molecular composites. Most specimens also reinforcing potential of rigid-rod polymers in molecular composites. Most specimens also exhibited NMR signals indicative of mobile, and presumably lower-molecular-weight, species. It is postulated that these mobile species are either water or residual acid from which the materials are processed. Information regarding the location of the mobile species in the structures exhibited by rigid-rod polymers and their blends with flexible polymers is deduced from NMR. Electron-spin resonance measurements confirmed that free radicals are generated during mechanically stressing rigid-rod polymer fibers. The as-processed fibers contained appreciable levels of free radicals, and annealing at elevated temperatures caused a decrease in the free-radical concentration by a factor of three. X-ray-diffraction experiments were conducted at elevated pressure in a diamond anvil cell. The observed diffraction pattern is suggestive of the formation of a more ordered structure at elevated pressures.

VanderHart, D.L.; Wang, F.W.; Eby, R.K.; Fanconi, B.M.; DeVries, K.L.

1986-02-01

6

Advanced microscopic and histochemical techniques: diagnostic tools in the molecular era of myology.  

PubMed

Over the past two centuries, myology (i.e. the basic and clinical science of muscle and muscle disease) has passed through 3 stages of development: the classical period, the modern stage and the molecular era. The classical period spans the last part of nineteenth century and the earlier part of the twentieth century. During this time, several major muscle diseases were clinically and pathologically characterized, including Duchenne muscular dystrophy (DMD), myotonic dystrophy (DM) and facioscapulohumeral dystrophy (FSHD). The modern stage in the second half of the twentieth century is characterized by the adaptation of histo and cytochemical techniques to the study of muscle biopsies. These tools improved the diagnostic accuracy and made possible the identification of new changes and structures (Engel and Cunningham, 1963; Scarlato, 1975). PMID:15823800

Meola, G

7

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

8

Inductive Sensing Technique Advancement.  

National Technical Information Service (NTIS)

The program is concerned with the advancement and development of the inductive sensing system. The system significantly enhanced in its ability to detect early fatigue damage in 6061 T-6 aluminum. Samples were fatigue cycled up to 2,000,000 cyles, and cra...

G. G. Moross

1971-01-01

9

Detecting the dormant: a review of recent advances in molecular techniques for assessing the viability of bacterial endospores.  

PubMed

Due to their contribution to gastrointestinal and pulmonary disease, their ability to produce various deadly exotoxins, and their resistance to extreme temperature, pressure, radiation, and common chemical disinfecting agents, bacterial endospores of the Firmicutes phylum are a major concern for public and environmental health. In addition, the hardy and dormant nature of endospores renders them a particularly significant threat to the integrity of robotic extraterrestrial life-detection investigations. To prevent the contamination of critical surfaces with seemingly ubiquitous bacterial endospores, clean rooms maintained at exceedingly stringent cleanliness levels (i.e., fewer than 100,000 airborne particles per ft(3)) are used for surgical procedures, pharmaceutical processing and packaging, and fabrication and assembly of medical devices and spacecraft components. However, numerous spore-forming bacterial species have been reported to withstand typical clean room bioreduction strategies (e.g., UV lights, maintained humidity, paucity of available nutrients), which highlights the need for rapid and reliable molecular methods for detecting, enumerating, and monitoring the incidence of viable endospores. Robust means of evaluating and tracking spore burden not only provide much needed information pertaining to endospore ecophysiology in different environmental niches but also empower decontamination and bioreduction strategies aimed at sustaining the reliability and integrity of clean room environments. An overview of recent molecular advances in detecting and enumerating viable endospores, as well as the expanding phylogenetic diversity of pathogenic and clean room-associated spore-forming bacteria, ensues. PMID:23912118

Mohapatra, Bidyut R; La Duc, Myron T

2013-08-03

10

Advances in Radar Techniques  

NASA Astrophysics Data System (ADS)

Most of the clutter received by L, S, C, X, and Ku band radars obeys a Weibull ditribution. To suppress such Weibull-distributed sea and weather clutter, Weibull CFAR techniques are applied to data taken by an X-band radar using computer in real time. The results show the usefulness of Weibull CFAR.

Sekine, Matsuo

11

Advanced Wavefront Control Techniques  

SciTech Connect

Programs at LLNL that involve large laser systems--ranging from the National Ignition Facility to new tactical laser weapons--depend on the maintenance of laser beam quality through precise control of the optical wavefront. This can be accomplished using adaptive optics, which compensate for time-varying aberrations that are often caused by heating in a high-power laser system. Over the past two decades, LLNL has developed a broad capability in adaptive optics technology for both laser beam control and high-resolution imaging. This adaptive optics capability has been based on thin deformable glass mirrors with individual ceramic actuators bonded to the back. In the case of high-power lasers, these adaptive optics systems have successfully improved beam quality. However, as we continue to extend our applications requirements, the existing technology base for wavefront control cannot satisfy them. To address this issue, this project studied improved modeling tools to increase our detailed understanding of the performance of these systems, and evaluated novel approaches to low-order wavefront control that offer the possibility of reduced cost and complexity. We also investigated improved beam control technology for high-resolution wavefront control. Many high-power laser systems suffer from high-spatial-frequency aberrations that require control of hundreds or thousands of phase points to provide adequate correction. However, the cost and size of current deformable mirrors can become prohibitive for applications requiring more than a few tens of phase control points. New phase control technologies are becoming available which offer control of many phase points with small low-cost devices. The goal of this project was to expand our wavefront control capabilities with improved modeling tools, new devices that reduce system cost and complexity, and extensions to high spatial and temporal frequencies using new adaptive optics technologies. In FY 99, the second year of this project, work was performed in four areas (1) advanced modeling tools for deformable mirrors (2) low-order wavefront correctors with Alvarez lenses, (3) a direct phase measuring heterdyne wavefront sensor, and (4) high-spatial-frequency wavefront control using spatial light modulators.

Olivier, S S; Brase, J M; Avicola, K; Thompson, C A; Kartz, M W; Winters, S; Hartley, R; Wihelmsen, J; Dowla, F V; Carrano, C J; Bauman, B J; Pennington, D M; Lande, D; Sawvel, R M; Silva, D A; Cooke, J B; Brown, C G

2001-02-21

12

Advances in Atomic & Molecular Nanotechnology  

Microsoft Academic Search

In this report the author is presenting the advances made in the atomic and molecular nanotechnology, ability to systematically organize and manipulate properties and behavior of matter in the atomic and molecular levels. It is argued that through nanotechnology it has become possible to create functional devices, materials and systems on the 1 to 100 nanometer (one billionth of a

G. Ali Mansoori

2002-01-01

13

Review of advanced imaging techniques  

PubMed Central

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

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

2012-01-01

14

Review of advanced imaging techniques.  

PubMed

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

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

2012-05-28

15

Techniques in Advanced Language Teaching.  

ERIC Educational Resources Information Center

|For ease of presentation, advanced grammar teaching techniques are briefly considered under the headings of structuralism (belief in the effectiveness of presenting grammar rules) and contextualism (belief in the maximum use by students of what they know in the target language). The structuralist's problem of establishing a syllabus is discussed…

Ager, D. E.

1967-01-01

16

Molecular Advances in Pancreatic Cancer  

Microsoft Academic Search

Our understanding of the molecular genetics of pancreatic cancer has advanced spectacularly over the last 5 years so that this tumour type is now one of the best characterised of all malignancies. A small proportion of cases results from inherited predisposition due to germline transmission of a mutated CDKN2 or BRCA2 gene, while patients with familial pancreatitis due to a

Nicholas R. Lemoine

1997-01-01

17

Advancment in Nuclear Detection Techniques  

NASA Astrophysics Data System (ADS)

Advanced nuclear detection techniques are being developed to aid in the diagnosis and treatment of breast cancer. Specifically, compact, portable devices which can be utilized in surgeries or for spot imaging are being optimized for a variety of applications. Issues include choice of optimial scintillation material, scintillator / photomultiplier coupling, collimation geometry, and readout electronics. A discussion of these issues, including test results from recent device development at the Duke University Medical Center, Hampton University, and the Jefferson Lab, will be presented.

Munden, A.; Keppel, C.

2000-10-01

18

Overview of recent advances in molecular cardiology  

PubMed Central

Molecular cardiology is a new and fast-growing area of cardiovascular medicine that aims to apply molecular biology techniques for the mechanistic investigation, diagnosis, prevention and treatment of cardiovascular disease. As an emerging discipline, it has changed conceptual thinking of cardiovascular development, disease etiology and pathophysiology. Although molecular cardiology is still at a very early stage, it has opened a promising avenue for understanding and controlling cardiovascular disease. With the rapid development and application of molecular biology techniques, scientists and clinicians are closer to curing heart diseases that were thought to be incurable 20 years ago. There clearly is a need for a more thorough understanding of the molecular mechanisms of cardiovascular diseases to promote the advancement of stem cell therapy and gene therapy for heart diseases. The present paper briefly reviews the state-of-the-art techniques in the following areas of molecular cardiology: gene analysis in the diseased heart; transgenic techniques in cardiac research; gene transfer and gene therapy for cardiovascular disease; and stem cell therapy for cardiovascular disease.

Sun, Zhongjie

2006-01-01

19

Molecular simulation of photoresists I: basic techniques for molecular simulation  

NASA Astrophysics Data System (ADS)

Recent advances in computer hardware and software have provided the capability to simulate complex mixtures of compounds on a molecular level. These tools provide the potential for exploration of resist chemistry and mechanism on a molecular level with visual feedback. However, there are still limitations of software and hardware and time which require simplification of the simulations. Thus extensive methods development will be required to be able to produce simulations useful to predict resist properties. This paper discusses the basics of photoresist molecular simulation techniques, limitations of the current techniques, and the potential for using molecular simulations to explore various aspects of photoresist performance, particularly novolac-novolac and novolac-diazonaphthoquinone photoactive compound (DNQ PAC) hydrogen bonding.

Blakeney, Andrew J.; Ferreira, Lawrence; Reynolds, Nicholas M.

1995-06-01

20

Advanced techniques for microwave reflectometry  

SciTech Connect

Microwave reflectometry has been applied during the last years as a plasma diagnostic of increasing interest, mainly due to its simplicity, no need for large access ports and low radiation damage of exposed components. Those characteristics make reflectometry an attractive diagnostic for the next generation devices. Systems used either for density profile or density fluctuations have also shown great development, from the original single channel heterodyne to the multichannel homodyne receivers. In the present work we discuss three different advanced reflectometer systems developed by CIEMAT members in collaboration with different institutions. The first one is the broadband heterodyne reflectometer installed on W7AS for density fluctuations measurements. The decoupling of the phase and amplitude of the reflected beam allows for quantitative analysis of the fluctuations. Recent results showing the behavior of the density turbulence during the L-H transition on W7AS are shown. The second system shows how the effect of the turbulence can be used for density profile measurements by reflectometry in situations where the complicated geometry of the waveguides cannot avoid many parasitic reflections. Experiments from the TJ-I tokamak will be shown. Finally, a reflectometer system based on the Amplitude Modulation (AM) technique for density profile measurements is discussed and experimental results from the TJ-I tokamak are shown. The AM system offers the advantage of being almost insensitive to the effect of fluctuations. It is able to take a direct measurement of the time delay of the microwave pulse which propagates to the reflecting layer and is reflected back. In order to achieve fast reconstruction for real time monitoring of the density profile application of Neural Networks algorithms will be presented the method can reduce the computing times by about three orders of magnitude. 10 refs., 10 figs.

Sanchez, J.; Branas, B.; Luna, E. de la; Estrada, T. [Asociacion Euratom-CIEMAT, Madrid (Spain); Zhuravlev, V. [Asociacion Euratom-CIEMAT, Madrid (Spain)]|[Kurchatov Institute, Moscow (Russian Federation); Hartfuss, H.J.; Hirsch, M.; Geist, T. [Max-Planck Institut fuer Plasmaphysik, Garching (Germany); Segovia, J.; Oramas, J.L. [Univ. Politecnica, Madrid (Spain)

1994-12-31

21

Guide to molecular cloning techniques  

SciTech Connect

This book includes the following selections: requirements for a molecular biology laboratory; general methods for isolating and characterizing nucleic acids; enzymatic techniques and recombinant DNA technology; restriction enzymes; growth and maintenance of bacteria; genetic cloning, preparation and characterization of RNA; preparation of cDNA and the generation of cDNA libraries; selections of clones from libraries; and identification and characterization of specific clones.

Berger, S.L.; Kimmel, A.R.

1987-01-01

22

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.

Zaidi, Habib; Prasad, Rameshwar

2009-01-01

23

Advanced Spectroscopy Technique for Biomedicine  

NASA Astrophysics Data System (ADS)

This chapter presents an overview of the applications of optical spectroscopy in biomedicine. We focus on the optical design aspects of advanced biomedical spectroscopy systems, Raman spectroscopy system in particular. Detailed components and system integration are provided. As examples, two real-time in vivo Raman spectroscopy systems, one for skin cancer detection and the other for endoscopic lung cancer detection, and an in vivo confocal Raman spectroscopy system for skin assessment are presented. The applications of Raman spectroscopy in cancer diagnosis of the skin, lung, colon, oral cavity, gastrointestinal tract, breast, and cervix are summarized.

Zhao, Jianhua; Zeng, Haishan

24

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

25

Advanced ECCM techniques for GPS processing  

Microsoft Academic Search

Two advanced Electronic Counter Countermeasures (ECCM) enhancement techniques were shown to greatly improve the antijam performance of Global Positioning System (GPS) receivers. The first method, Amplitude Domain Processing (ADP), is a nonlinear precorrelation processing technique which adapts to a changing ECM environment and exploits the statistical properties of strong nonGaussian jammers to significantly reduce their effectiveness. ADP was demonstrated in

Edmund Balboni; John Dowdle; Joseph Przyjemski; Ellen Mallery

1991-01-01

26

Advanced AE Techniques in Composite Materials Research  

Microsoft Academic Search

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

William H. Prosser

1996-01-01

27

Advanced Technique in Breast Thermography Analysis  

Microsoft Academic Search

Thermography is a non-invasive and non-contact imaging technique used widely in the medical arena. This paper investigates the analysis of thermograms with the use of bio-statistical methods and artificial neural networks (ANN). It is desired that through these approaches, highly accurate diagnosis using thermography techniques can be established. The proposed advanced technique, is a multi-pronged approach comprising of linear regression

E. Y. K. Ng; E. C. Kee; R. Acharya U

2005-01-01

28

Oncological molecular imaging: nuclear medicine techniques  

Microsoft Academic Search

With the expanding interest and development in mol- ecular biology, nuclear medicine imaging, essentially a molecular imaging technique studying biological processes at the cellular and molecular level, has much to offer. As other non-isotope techniques develop there has also been an opportunity for nuclear medicine to broaden its horizons in this field. Nuclear medicine's involvement in molecular imaging has been

G J R Cook

2003-01-01

29

Advances in Molecular Imaging with Ultrasound  

PubMed Central

Ultrasound imaging has long demonstrated utility in the study and measurement of anatomic features and noninvasive observation of blood flow. Within the last decade, advances in molecular biology and contrast agents have allowed researchers to use ultrasound to detect changes in the expression of molecular markers on the vascular endothelium and other intravascular targets. This new technology, referred to as ultrasonic molecular imaging, is still in its infancy. However, in preclinical studies, ultrasonic molecular imaging has shown promise in assessing angiogenesis, inflammation, and thrombus. In this review, we discuss recent advances in microbubble-type contrast agent development, ultrasound technology, and signal processing strategies that have the potential to substantially improve the capabilities and utility of ultrasonic molecular imaging.

Gessner, Ryan; Dayton, Paul A.

2010-01-01

30

Signature Molecular Descriptor: Advanced Applications.  

National Technical Information Service (NTIS)

In this work we report on the development of the Signature Molecular Descriptor (or Signature) for use in the solution of inverse design problems as well as in highthroughput screening applications. The ultimate goal of using Signature is to identify nove...

D. P. Visco

2010-01-01

31

International acceptability of advanced safeguarding techniques  

Microsoft Academic Search

There are active development programs now under way to significantly enhance the effectiveness of international safeguarding. Advanced safeguarding techniques now under development include new material accounting methods utilizing nondestructive assay techniques, more reliable surveillance instrumentation, tamper-resistant and tamper-indicating seals, new means of utilizing continuous human inspection, and systems that incorporate both passive and active use-denial technologies. Before these new safeguarding

Barkenbus

1979-01-01

32

Introduction To Basic Molecular Biologic Techniques For Molecular Imaging  

Microsoft Academic Search

Molecular imaging is a rapidly growing field due to the advances in molecular biology and imaging technologies. With the introduction of imaging reporter genes into the cell, diverse cellular processes can be monitored, quantified and imaged non-invasively in vivo. These processes include the gene expression, protein-protein interactions, signal transduction pathways, and monitoring of cells such as cancer cells, immune cells,

Joo Hyun Kang

33

Advances in plant molecular farming.  

PubMed

Plant molecular farming (PMF) is a new branch of plant biotechnology, where plants are engineered to produce recombinant pharmaceutical and industrial proteins in large quantities. As an emerging subdivision of the biopharmaceutical industry, PMF is still trying to gain comparable social acceptance as the already established production systems that produce these high valued proteins in microbial, yeast, or mammalian expression systems. This article reviews the various cost-effective technologies and strategies, which are being developed to improve yield and quality of the plant-derived pharmaceuticals, thereby making plant-based production system suitable alternatives to the existing systems. It also attempts to overview the different novel plant-derived pharmaceuticals and non-pharmaceutical protein products that are at various stages of clinical development or commercialization. It then discusses the biosafety and regulatory issues, which are crucial (if strictly adhered to) to eliminating potential health and environmental risks, which in turn is necessary to earning favorable public perception, thus ensuring the success of the industry. PMID:21115109

Obembe, Olawole O; Popoola, Jacob O; Leelavathi, Sadhu; Reddy, Siva V

2010-11-27

34

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

35

Advanced MR techniques in multicenter clinical trials.  

PubMed

MRI has had a place in the clinical trials process for more than 20 years. However, for much of that time MRI has been used primarily for subjective interpretation and relatively straightforward structural measurements. More advanced MR techniques have been considered too difficult to implement consistently across multiple sites in a single trial--this despite the fact that these techniques often provide the best window into the direct effects of targeted therapeutics. As an example, numerous compounds are currently under development whose principle effect is to temporarily or permanently alter tumor microvasculature. Changes induced by these compounds typically manifest as reductions in blood flow and vascular permeability within tumors. These changes can be measured directly using dynamic contrast-enhanced MRI. Early studies using this technique were limited to single centers, limiting both the overall size of the studies and the rate at which they were able to accrue patients. Recent efforts, however, have demonstrated that with sufficient attention to protocol design, imaging site selection and training, and analysis standardization, it is possible to obtain consistent and high quality results using even relatively complex acquisition protocols. This article will briefly review both the benefits and the drawbacks of including advanced MR techniques in clinical trial protocols. It will then review in detail the challenges presented by the need to deploy these techniques both to large research institutions and to community imaging centers which may have little or no familiarity with them at the outset of the trial. PMID:23526755

Ashton, Edward; Riek, Jonathan

2013-04-01

36

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.

Kerwin, William S.; Canton, Gador

2011-01-01

37

Advances in pediatric colorectal surgical techniques.  

PubMed

The operative management of pediatric colorectal diseases has improved significantly in recent years through the development of innovative approaches for operative exposure and a better understanding of colorectal anatomy. Advances in transanal and minimal access techniques have formed the cornerstone of this innovation, leading to improved functional outcomes, earlier recovery, and superior cosmetic results for a number of colorectal diseases. In this regard, we have witnessed a significant evolution in the way that many of these conditions are managed, particularly in the areas of anorectal malformations and Hirschsprung disease. Furthermore, a more thorough understanding of the pathophysiology underlying encopresis and true fecal continence has led to novel and less invasive approaches to the operative management of these conditions. The goal of this review is to describe the evolution of operative management pertaining to these diseases, with an emphasis on technical aspects and relevant clinical pitfalls. PMID:20307845

Rangel, Shawn J; de Blaauw, Ivo

2010-05-01

38

Advanced techniques in current signature analysis  

SciTech Connect

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 an 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 (>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. 3 refs.

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

1992-03-01

39

Advances in nanodiagnostic techniques for microbial agents.  

PubMed

Infectious diseases account for millions of sufferings and deaths in both developing as well as developed countries with a substantial economic loss. Massive increase in world population and international travel has facilitated their spread from one part of the world to other areas, making them one of the most significant global health risks. Furthermore, detection of bioterrorism agents in water, food and environmental samples as well traveler's baggage is a great challenge of the time for security purpose. Prevention strategies against infectious agents demand rapid and accurate detection and identification of the causative agents with highest sensitivity which should be equally available in different parts of the globe. Similarly, rapid and early diagnosis of infectious diseases has always been indispensable for their prompt cure and management, which has stimulated scientists to develop highly sophisticated techniques over centuries and the efforts continue unabated. Conventional diagnostic techniques are time consuming, tedious, expensive, less sensitive, and unsuitable for field situations. Nanodiagnostic assays have been promising for early, sensitive, point-of-care and cost-effective detection of microbial agents. There has been an explosive research in this area of science in last two decades yielding highly fascinating results. This review highlights some of the advancements made in the field of nanotechnology based assays for microbial detection since 2005 along with providing the basic understanding. PMID:24012709

Syed, Muhammad Ali

2013-08-22

40

Study of Microcircuitry Techniques Utilizing Molecular Engineering.  

National Technical Information Service (NTIS)

The major accomplishments of the contract program were: (1) An extensive study of molecular techniques for the fabrication of X and Y-amplifiers for peripheral driver circuitry of solid state display systems. (2) The development of a planar all-diffused p...

1965-01-01

41

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

2013-04-03

42

Cancer Diagnosis by Terahertz Molecular Imaging Technique  

NASA Astrophysics Data System (ADS)

We obtained the diagnostic images of cancerous tumors by employing the THz molecular imaging (TMI) technique which measured the THz response change by surface plasmon resonance induced on the surface of nanoparticles with a irradiation of near-infrared (NIR) beam. To demonstrate the principle of the TMI technique, THz images of tissues with nanoprobes were observed and compared with THz only images. The sensitivity of TMI was further enhanced by adopting a THz differential measurement technique, which was realized by modulating the NIR beams. By employing this differential TMI technique, the diagnostic images of cancerous tumors were obtained ex vivo and in vivo in the preclinical stage. These images indicated the feasibility of applying the differential TMI technique in the clinical stage.

Oh, Seung Jae; Huh, Yong-Min; Suh, Jin-Suck; Choi, Jihye; Haam, Seungjoo; Son, Joo-Hiuk

2012-01-01

43

The application of advanced analytical techniques to direct coal liquefaction  

Microsoft Academic Search

Consol is coordinating a program designed to bridge the gap between the advanced, modern techniques of the analytical chemist and the application of those techniques by the direct coal liquefaction process developer, and to advance our knowledge of the process chemistry of direct coal liquefaction. The program is designed to provide well-documented samples to researchers who are utilizing techniques potentially

S. D. Brandes; R. A. Winschel; F. P. Burke; G. A. Robbins

1991-01-01

44

New molecular targets in advanced prostate cancer.  

PubMed

Classically, advanced prostate cancer has been treated with hormonal therapy and, most recently, chemotherapy. This treatment clearly demonstrated a survival benefit, but never a cure. With the ever-expanding understanding of the pathophysiology of prostate cancer, there has been a recent explosion in the potential molecular targets and novel therapeutic approaches to both advanced and potentially localized prostate cancer. This review will focus on what the author perceives to be the most promising of these new strategies. The endothelin pathway has been identified as pivotal in the viscous cycle of tumorigenesis in bone, leading to the development of endothelial receptor antagonists. Vaccine therapy using autologous granulocyte-macrophage colony-stimulating factor-producing prostate cancer cells has been effective in producing both immune and clinical responses. Randomized clinical trials of the immunotherapy cell product APC8015 (Provenge) have demonstrated improved survival in the hormone-refractory setting. The development of antisense oligonucleotides to segments of mRNA critical to the progression to androgen-independent disease has emerged as one further tool in the expanding armamentarium of potential therapies being tested. Clearly, headway is being made in improving outcomes in this most prevalent health problem. PMID:16831072

Dawson, Nancy A

2006-07-01

45

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

46

Advances in structural and molecular neuroimaging in Alzheimer's disease.  

PubMed

Longer life expectancies lead to increases in the prevalence of age-associated illnesses. The number of Australians with dementia is predicted to rise, from 234,000 in 2009 to over 1 million by 2050, as a result of the increased prevalence of Alzheimer's disease (AD), the leading cause of dementia in the elderly. Early diagnosis of AD will become more important as disease-modifying therapies emerge within the next decade. Advances in molecular neuroimaging with amyloid-?-specific radioligands for positron emission tomography, aided by magnetic resonance imaging techniques, allow detection of AD years before symptoms of dementia develop. Longitudinal prospective studies, such as the Australian Imaging Biomarkers and Lifestyle (AIBL) study of ageing, will determine the sensitivity and specificity of these analysis techniques for diagnosing AD and predicting cognitive decline. PMID:21401483

Ellis, Kathryn A; Rowe, Christopher C; Szoeke, Cassandra E I; Villemagne, Victor L; Ames, David; Chételat, Gaël; Martins, Ralph N; Masters, Colin L; Fripp, Jurgen; Acosta, Oscar; Raniga, Parnesh; Bourgeat, Pierrick T; Salvado, Olivier

2011-02-21

47

Advanced Techniques Employed in Blade Cooling Research.  

National Technical Information Service (NTIS)

The design of an advance cooling system for moderately cooled second stage gas turbine engine blades was undertaken as part of a demonstration project. The design process involving complex computer modeling and hot rig testing of the blades is described. ...

H. E. Rogers C. Graham K. McNicholas

1987-01-01

48

Advanced Techniques for Improving Laser Optical Surfaces.  

National Technical Information Service (NTIS)

This program is a study of surface-finishing techniques considered to be capable of improving the surface quality of laser optical materials. A variety of conventional and superpolishing techniques will be developed for single-crystal and polycrystalline ...

C. B. Willingham

1974-01-01

49

ADVANCES IN MOLECULAR IMAGING OF PANCREATIC BETA CELLS  

PubMed Central

The development of non-invasive imaging methods for early diagnosis of the beta cell associated metabolic diseases, including type 1 and type 2 diabetes (T1D and T2D), has recently drawn considerable interest from the molecular imaging community as well as clinical investigators. Due to the challenges imposed by the location of the pancreas, the sparsely dispersed beta cell population within the pancreas, and the poor understanding of the pathogenesis of the diseases, clinical diagnosis of beta cell abnormalities is still limited. Current diagnostic methods are invasive, often inaccurate, and usually performed post-onset of the disease. Advances in imaging techniques for probing beta cell mass and function are needed to address this critical health care problem. A variety of currently available imaging techniques have been tested for the assessment of the pancreatic beta cell islets. Here we discuss the current advances in magnetic resonance imaging (MRI), bioluminescence imaging (BLI), and nuclear imaging for the study of beta cell diseases. Spurred by early successes in nuclear imaging techniques for beta cells, especially positron emission tomography (PET), the need for beta cell specific ligands has expanded. Progress in the field for obtaining such ligands is presented. Additionally, we report our preliminary efforts of developing such a peptidic ligand for PET imaging of the pancreatic beta cells.

Lin, Mai; Lubag, Angelo; McGuire, Michael J.; Seliounine, Serguei Y.; Tsyganov, Edward N.; Antich, Peter P.; Sherry, A. Dean; Brown, Kathlynn C.; Sun, Xiankai

2009-01-01

50

Advanced Techniques for Improving Laser Optical Surfaces.  

National Technical Information Service (NTIS)

Chemical and chemical-mechanical polishing, ion-beam polishing, bowl-feed and continuously recycled abrasive 'super-polishing' techniques were evaluated for single crystal and polycrystalline potassium chloride and calcium fluoride, and polycrystalline zi...

C. B. Willingham D. P. Bua M. R. Schapira R. H. Cosgro

1975-01-01

51

Advanced Sensor Signal Processing Using Optical Techniques.  

National Technical Information Service (NTIS)

A Fourier transform based iterative technique is presented for solution of Toeplitz and general matrix equations resulting in an algorithm for the determination of an adaptive beam steering vector from the radar covariance matrix. An associated optoelectr...

L. A. Eichel W. R. Franklin L. H. Gesell R. Kallman S. Evanko

1997-01-01

52

Advances in Radar Signal Processing Techniques  

NASA Astrophysics Data System (ADS)

Weibull-distributed clutter are reviewed. Most of the clutter received by L, S, X and Ku band radars obeys a Weibull distribution when reflectors are terrain, sea, sea-ice and rain clouds. Clutter suppression techniques for Weibull clutter are also reviewed. Especially, Weibull CFAR is emphasized.

Sekine, Matsuo; Sayama, Shuji

53

Advanced nuclear analytical techniques for metalloproteomics  

Microsoft Academic Search

Metalloproteomics is an emerging scientific field. It is focused to investigate the distributions and compositions of all metalloproteins in a proteome, their structural and functional characterization and their structural metal-binding moieties. Various nuclear analytical techniques, such as neutron activation analysis, X-ray fluorescence, isotope tracer, Mossbauer spectrometry, X-ray absorption spectrometry and neutron scattering and diffraction, are powerful tools to study a

Yuxi Gao; Chunying Chenab; Zhifang Chai

2007-01-01

54

Advanced optical characterization techniques for borophosphosilicate films  

NASA Astrophysics Data System (ADS)

FTIR spectra of borophosphosilicate (BPSG) films which are obtained by metal backed configurations are compared to those obtained by the conventional normal incidence transmission geometry. Sensitivity advantages are demonstrated for both hydrogen incorporation and dopant analyses. P-polarized measurements are explored for preferential excitation of vibrational modes. Reflectance measurements of BPSG films on silicon by FTIR and by the emerging techniques of spectroscopic ellipsometry (SE) both in the UV-visible and mid-IR spectral ranges are reviewed. The use of differential and derivative spectral data anlysis is illustrated for investigating structural and compositional changes which occur from film densification and in the course of film storage.

Carpio, Ronald A.; Taylor, Jon

1995-09-01

55

Advanced automated char image analysis techniques  

SciTech Connect

Char morphology is an important characteristic when attempting to understand coal behavior and coal burnout. In this study, an augmented algorithm has been proposed to identify char types using image analysis. On the basis of a series of image processing steps, a char image is singled out from the whole image, which then allows the important major features of the char particle to be measured, including size, porosity, and wall thickness. The techniques for automated char image analysis have been tested against char images taken from ICCP Char Atlas as well as actual char particles derived from pyrolyzed char samples. Thirty different chars were prepared in a drop tube furnace operating at 1300{sup o}C, 1% oxygen, and 100 ms from 15 different world coals sieved into two size fractions (53-75 and 106-125 {mu}m). The results from this automated technique are comparable with those from manual analysis, and the additional detail from the automated sytem has potential use in applications such as combustion modeling systems. Obtaining highly detailed char information with automated methods has traditionally been hampered by the difficulty of automatic recognition of individual char particles. 20 refs., 10 figs., 3 tabs.

Tao Wu; Edward Lester; Michael Cloke [University of Nottingham, Nottingham (United Kingdom). School of Chemical, Environmental and Mining Engineering

2006-05-15

56

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

57

Recent advances in DNA sequencing techniques  

NASA Astrophysics Data System (ADS)

Successful mapping of the draft human genome in 2001 and more recent mapping of the human microbiome genome in 2012 have relied heavily on the parallel processing of the second generation/Next Generation Sequencing (NGS) DNA machines at a cost of several millions dollars and long computer processing times. These have been mainly biochemical approaches. Here a system analysis approach is used to review these techniques by identifying the requirements, specifications, test methods, error estimates, repeatability, reliability and trends in the cost reduction. The first generation, NGS and the Third Generation Single Molecule Real Time (SMART) detection sequencing methods are reviewed. Based on the National Human Genome Research Institute (NHGRI) data, the achieved cost reduction of 1.5 times per yr. from Sep. 2001 to July 2007; 7 times per yr., from Oct. 2007 to Apr. 2010; and 2.5 times per yr. from July 2010 to Jan 2012 are discussed.

Singh, Rama Shankar

2013-06-01

58

Advanced techniques for enhancing wireless RF transmitters' power efficiency  

Microsoft Academic Search

This paper expounds on power efficiency enhancement techniques that are sought for the reduction of power consumption of wireless radio frequency power amplifiers (RFPA) and transmitters. The paper will focus on advanced power amplification architectures such as doherty power amplifiers (DPA), linear amplification using nonlinear components (LINC), envelop elimination and restoration (EER) and envelope tracking (ET) techniques. Overview on each

Slim Boumaiza

2008-01-01

59

Advances in Velocimetry Techniques for Plasma Turbulence  

NASA Astrophysics Data System (ADS)

The HOP-V (Hybrid OPtical-flow Velocimetry) code has been developed for extracting time-resolved 2-D velocity maps from turbulence imaging diagnostics. The HOP-V code combines optical-flow and local pattern-matching techniques to derive ``dense'' velocity fields at the full temporal resolution and a fraction of the spatial resolution of the underlying image frames, often tens of pixels per side and thousands of timepoints in duration, with temporal and spatial resolution sufficient to resolve the relevant coherence decay quantities. Recent work has resulted in a new module to the HOP-V code, using a ``next generation'' optical flow approach capable of obtaining accurate flow-fields from highly nonrigid motion, as is commonly the case in turbulent scalar measurements. This approach not only derives flow fields containing local curl, but also simultaneously provides a decomposition of the flow field into a coherent pattern with separable small-scale patterns. This can be particularly important in separating the local ``swirling'' motion from flows having a more global impact on transport.

Brown, Benjamin; Munsat, T.; Sechrest, Y.; Sen, N.

2009-11-01

60

Advancing uracil-excision based cloning towards an ideal technique for cloning PCR fragments  

PubMed Central

The largely unused uracil-excision molecular cloning technique has excellent features in most aspects compared to other modern cloning techniques. Its application has, however, been hampered by incompatibility with proof-reading DNA polymerases. We have advanced the technique by identifying PfuCx as a compatible proof-reading DNA polymerase and by developing an improved vector design strategy. The original features of the technique, namely simplicity, speed, high efficiency and low cost are thus combined with high fidelity as well as a transparent, simple and flexible vector design. A comprehensive set of vectors has been constructed covering a wide range of different applications and their functionality has been confirmed.

Nour-Eldin, Hussam H.; Hansen, Bjarne G.; N?rholm, Morten H. H.; Jensen, Jacob K.; Halkier, Barbara A.

2006-01-01

61

Advancing molecular imaging: a chairman’s perspective on how radiology can meet the challenge  

Microsoft Academic Search

To date, most molecular imaging techniques applied clinically have offered relatively general information about the metabolism\\u000a and physiology of diseased cells and tissues. However, due to recent scientific and technological advances, much more specifically\\u000a targeted molecular imaging probes (e.g., reporter gene probes, whole cell-tracking probes, and probes for localizing specific\\u000a biomolecules) are now being used in preclinical research and, in

Hedvig Hricak

2011-01-01

62

Advances in molecular genetics of panic disorder  

Microsoft Academic Search

The molecular genetic research on panic disorder (PD) has grown tremendously in the past decade. Although the data from twin and family studies suggest an involvement of genetic factors in the familial transmission of PD with the heritability estimate near 40%, the genetic substrate underlying panicogenesis is not yet understood. The linkage studies so far have suggested that chromosomal regions

E Maron; J M Hettema; J Shlik

2010-01-01

63

Advances in gamma titanium aluminides and their manufacturing techniques  

NASA Astrophysics Data System (ADS)

Gamma titanium aluminides display attractive properties for high temperature applications. For over a decade in the 1990s, the attractive properties of titanium aluminides were outweighed by difficulties encountered in processing and machining at room temperature. But advances in manufacturing technologies, deeper understanding of titanium aluminides microstructure, deformation mechanisms, and advances in micro-alloying, has led to the production of gamma titanium aluminide sheets. An in-depth review of key advances in gamma titanium aluminides is presented, including microstructure, deformation mechanisms, and alloy development. Traditional manufacturing techniques such as ingot metallurgy and investment casting are reviewed and advances via powder metallurgy based manufacturing techniques are discussed. Finally, manufacturing challenges facing gamma titanium aluminides, as well as avenues to overcome them, are discussed.

Kothari, Kunal; Radhakrishnan, Ramachandran; Wereley, Norman M.

2012-11-01

64

Molecular Genetics Techniques to Develop New Treatments for Brain Cancers  

SciTech Connect

The objectives of this report are: (1) to devise novel molecular gene therapies for malignant brain tumors, (2) advance our understanding of the immune system in the central nervous system; and (3) apply genomics to find molecular probes to diagnose brain tumors, predict prognosis, biological behavior and their response to treatment.

Fox, Jacob; Fathallan-Shaykh, Hassan

2006-09-22

65

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

66

Optical Fourier transform techniques for advanced Fourier spectroscopy systems.  

PubMed

A review of multichannel long integration time, optical Fourier transform techniques for advanced Fourier spectroscopy systems is followed by the description of a new multichannel time-integrating optical Fourier transform chirp-Z system and a discussion of its use in Fourier spectroscopy signal processing. PMID:20221177

Casasent, D; Psaltis, D

1980-06-15

67

Advanced programming techniques applied to Cgal's arrangement package  

Microsoft Academic Search

Arrangements of planar curves are fundamental structures in computational geometry. Recently, the arrangement pack- age of Cgal, the Computational Geometry Algorithms Li- brary, has been redesigned and re-implemented exploiting several advanced programming techniques. The resulting software package, which constructs and maintains planar arrangements, is easier to use, to extend, and to adapt to a variety of applications, is more efficient

Ron Wein; Efi Fogel; Baruch Zukerman; Dan Halperin

2007-01-01

68

Advanced maneuvering reentry vehicle instrumentation and communication techniques  

Microsoft Academic Search

This paper describes instrumentation and communication techniques used in the data gathering process for presently ongoing high performance advanced maneuvering reentry vehicle test flights. Transducers and signal conditioning design considerations including flight test results of vibration and acoustic data (gathered simultaneously by eight FM and one 24,824 sps PCM channel), nose and control surface load cells, control actuation, flow rates,

G. W. Galleher; A. J. Locklair

1981-01-01

69

Coal and char studies by advanced EMR techniques  

SciTech Connect

Advanced magnetic resonance (EMR) methods are used to examine properties of coals, chars, and molecular species related to constituents of coal. During this grant period, further progress was made on proton NMR and low-frequency dynamic nuclear polarization (DNP) to examine the interaction between fluids such as water and the surface of suspended char particles. Effects of char particle size on water nuclear spin relaxation, T2, were measured.

Belford, R.L.; Clarkson, R.B.; Odintsov, B.M.

1998-09-30

70

COAL AND COAL CONSTITUENT STUDIES BY ADVANCED EMR TECHNIQUES  

SciTech Connect

Advanced electronic magnetic resonance (EMR) methods are used to examine properties of coals, chars, and molecular species related to constituents of coal. During this grant period, progress was made on setting up a separate high frequency EMR system particularly appropriate for such studies and exploring the use of low-frequency dynamic nuclear polarization (DNP) to examine the interaction between fluids such as water and the surface of suspended char particles.

R. Linn Belford; Robert B. Clarkson

1997-03-28

71

Coal and char studies by advanced EMR techniques  

SciTech Connect

Advanced magnetic resonance (EMR) methods are used to examine properties of coals, chars, and molecular species related to constituents of coal. During this grant period, further progress was made on proton NMR and low-frequency dynamic nuclear polarization (DNP) to examine the interaction between fluids such as water and the surface of suspended char particles. Effects of char particle size and type on water nuclear spin relaxation, T2, were measured and modeled.

Belford, R.L.; Clarkson, R.B.; Odintsov, B.M.

1999-03-31

72

Coal and Coal Constituent Studies by Advanced EMR Techniques.  

SciTech Connect

Advanced electronic magnetic resonance (EMR) methods are used to examine properties of coals, chars, and molecular species related to constituents of coal. During this grant period, progress was made on a high frequency EMR system particularly appropriate for such studies and on low-frequency dynamic nuclear polarization (DNP) to examine the interaction between fluids such as water and the surface of suspended char particles.

Belford, R.L.; Clarkson, R.B.; Odintsov, B.; Ceroke, P.J.

1997-09-30

73

Automatic Molecular Design using Evolutionary Techniques.  

National Technical Information Service (NTIS)

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 softwar...

A. Globus J. Lawton T. Wipke

1998-01-01

74

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

PubMed

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

2012-03-01

75

Characterization of sSMC by FISH and molecular techniques.  

PubMed

Small supernumerary marker chromosome (sSMC) is a structurally altered additional chromosome that may not be explicitly clarified by conventional karyotyping alone. About one third of sSMC carriers have abnormal phenotypes and its clinical correlation is difficult, especially in prenatal studies. The present study was aimed at characterizing 19 sSMC identified in 15 patients with dysmorphic features with or without multiple congenital anomalies, conspicuous family history, short stature and/or ambiguous genitalia. All the sSMC were primarily identified by routine cytogenetics studies (performed with banding techniques) from peripheral blood except in one patient, where amniotic fluid was used. All sSMCs were further characterized by array-CGH (using 44 K oligonucleotide probe) and/or fluorescence in situ hybridization (FISH) using multicolor banding (MCB), centromere specific multicolor FISH (cenM-FISH), subcentromere-specific multicolor FISH (subcenM-FISH), micro-dissection and/or reverse FISH. This report demonstrates the worth of advanced molecular (cyto)genetic techniques in characterizing sSMC, their utility in genotype-phenotype correlation and risk of clinical presentation. PMID:21316495

Sheth, Frenny; Andrieux, Joris; Ewers, Elisabeth; Kosyakova, Nadezda; Weise, Anja; Sheth, Harsh; Romana, Serge-Pierrick; LeLorc'h, Marc; Delobel, Bruno; Theisen, Olivier; Liehr, Thomas; Nampoothiri, Sheela; Sheth, Jayesh

2011-03-03

76

Molecular hematology. Qualitative to quantitative techniques.  

PubMed

Over the last decade molecular diagnostics technology has developed dramatically from the most laborious, time- consuming southern blot methodology through the revolution of polymerase chain reaction PCR technology to the most reliable, fast, and contamination free molecular analyzer, the real-time quantitative-PCR. The Section of Hematology, Department of Pathology and Laboratory Medicine at King Faisal Specialist Hospital and Research Center has shared this experience during the last 10 years with more than 6,546 samples submitted for the analysis of different gene rearrangements, fusion gene transcripts and gene mutations including Ig heavy chain gene rearrangement for B-cell malignancies, T-cell receptor gamma chain gene rearrangement for T-cell malignancies, BCR/ABL-P210 and P190 fusion gene transcripts, for chronic myeloid leukemia and Philadelphia positive acute lymphoblastic leukemia, PML/RARalpha fusion gene for promyelocytic leukemia, AML1/ETO for acute myeloid leukemia AML-M2 with t8;21, CBFB/MYH11 for AML M4E0 with inv 16, BCL-2 for follicular lymphoma, and BCL-1 for mantle cell lymphoma. Hence, most molecular assays are qualitative in nature, quantitative assays are deemed necessary in the monitoring and follow-up of minimal residual disease in leukemia and lymphoma, and proved in our experience to serve as an essential tool to confirm complete remission CR post-chemotherapy and bone marrow transplantation, and to detect signs of early relapse for proper clinical intervention. In this manuscript, we retrospectively review our experience in molecular hematology and propose our recommended guidelines at King Faisal Specialist Hospital and Research Center. PMID:16228048

Khalil, Salem H

2005-10-01

77

Recent advances of laser-spectroscopy-based techniques for applications in breath analysis.  

PubMed

Laser absorption spectroscopy (LAS) in the mid-infrared region offers a promising new effective technique for the quantitative analysis of trace gases in human breath. LAS enables sensitive, selective detection, quantification and monitoring in real time, of gases present in breath. This review summarizes some of the recent advances in LAS based on semiconductor lasers and optical detection techniques for clinically relevant exhaled gas analysis in breath, specifically such molecular biomarkers as nitric oxide, ammonia, carbon monoxide, ethane, carbonyl sulfide, formaldehyde and acetone. PMID:21383427

McCurdy, Matthew R; Bakhirkin, Yury; Wysocki, Gerard; Lewicki, Rafal; Tittel, Frank K

2007-07-11

78

Putting into Practice Advanced Software Engineering Techniques through Students Project  

Microsoft Academic Search

The paper describes an experience of software engineering education concerning the guidance of students project during about ten years. The project aims mainly at putting into practice the concepts, methods and techniques taught in a software engineering course through the development -by teams of students- of an actual, practical, real-size case. The concerned course involves several advanced topics, e.g., semi-formal

Naji Habra; Eric Dubois

1994-01-01

79

[Research advances in molecular pathogenesis of thyroid cancer].  

PubMed

Thyroid cancer is the one of the most common endocrine tumors.The biological behaviors and prognoses of the thyroid cancer of different histological types remarkably differ.The highly invasive thyroid cancer responds poorly to traditional therapies.Recent research advances in the molecular mechanisms of the pathogenesis of thyroid cancer have revealed the roles of many genetic and epigenetic variations such as gene mutation,abnormal gene amplification,and abnormal gene methylation in the development of thyroid cancer,which provides new insights in the molecular diagnosis,prognosis,and target therapy of the thyroid cancer. PMID:23987483

Aleha, Maotihan; Meng, Qing-bin; Yu, Jian-chun; Kang, Wei-ming; Cao, Zhan-jiang; Tian, Shu-bo

2013-08-01

80

Hybrid opto-electric techniques for molecular diagnostics  

SciTech Connect

Hybrid optoelectric techniques reflect a new paradigm in microfluidics. In essence, these are microfluidic techniques that employ a synergistic combination of optical and electrical forces to enable noninvasive manipulation of fluids and/or particle-type entities at the micro/nano-scale [1]. Synergy between optical and electrical forces bestows these techniques with several unique features that are promising to bring new opportunities in molecular diagnostics. Within the scope of molecular diagnostics, several aspects of optoelectric techniques promise to play a relevant role. These include, but are not limited to, sample preparation, sorting, purification, amplification and detection.

Haque, Aeraj Ul [Argonne National Laboratory (ANL)

2012-01-01

81

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…

Stiller, John W.; Coggins, T. Chad

2006-01-01

82

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

83

The advances of electromigration techniques applied for alkaloid analysis.  

PubMed

Alkaloids are natural products of metabolism found mainly in plants. Their diversified pharmacological activities as medical agents and extensive occurrence in nutritional products demand the development of reliable and sensitive analytical tools. This review presents the developments in the field of electromigration techniques and specifically capillary and microchip electrophoresis. We include the main aspects of interest to researches over the past 12 years. The scope of this review covers detection, on- and off-line preconcentration techniques, chiral separation and developments in the field of microchip electrophoresis. Their applications in alkaloid determination, capillary electrochromatography and inter-molecular interactions are also examined. Copyright © 2013 John Wiley & Sons, Ltd. PMID:23813479

Dziomba, Szymon; Belka, Mariusz; Kowalski, Piotr; Plenis, Alina; B?czek, Tomasz

2013-07-01

84

Advanced techniques for penetration enhancement in transdermal drug delivery system.  

PubMed

Transdermal route has been recognized as a promising drug delivery system for systemic delivery of drugs and provides the advantage of avoidance of first-pass effect, ease of use, better patient compliance, maintaining constant blood level for longer period of time and decrease side effects. The major pitfalls of this route lie with difficulty in permeation of drugs through the skin. Several literatures have been published for enhancing the permeation of drugs by chemical approaches. However the present review highlighted about the advanced physical techniques used for enhancing delivery of drugs such as structure-based, electrically based, velocity based and several other miscellaneous physical techniques for enhancing the permeation of drugs. In addition to these, the present review also gives an exhaustive account on clinical data about these techniques and regulatory considerations for new drugs as well as generic product approval in transdermal drug delivery. PMID:21453254

Swain, Suryakanta; Beg, Sarwar; Singh, Astha; Patro, Ch Niranjan; Rao, M E Bhanoji

2011-07-01

85

Molecular techniques in the diagnosis of central nervous system infections  

Microsoft Academic Search

Development of polymerase chain reaction (PCR)-based molecular techniques has initiated a revolution in the field of diagnostic\\u000a microbiology. These techniques have not only provided rapid, noninvasive detection of microorganisms that cause central nervous\\u000a system (CNS) infections, but have also demonstrated that several neurologic disorders are linked to infectious agents. While\\u000a PCR-based techniques are predicted to be widely used in diagnosing

Hong-Zhou Lu; Karen C. Bloch; Yi-Wei Tang

2002-01-01

86

Molecular classification and novel targets in hepatocellular carcinoma: recent advancements.  

PubMed

Hepatocellular carcinoma (HCC) is one of most lethal cancers worldwide. Strategic decisions for the advancement of molecular therapies in this neoplasm require a clear understanding of its molecular classification. Studies indicate aberrant activation of signaling pathways involved in cellular proliferation (e.g., epidermal growth factor and RAS/mitogen-activated protein kinase pathways), survival (e.g., Akt/mechanistic target of rapamycin pathway), differentiation (e.g., Wnt and Hedgehog pathways), and angiogenesis (e.g., vascular endothelial growth factor and platelet-derived growth factor), which is heterogeneously presented in each tumor. Integrative analysis of accumulated genomic datasets has revealed a global scheme of molecular classification of HCC tumors observed across diverse etiologic factors and geographic locations. Such a framework will allow systematic understanding of the frequently co-occurring molecular aberrations to design treatment strategy for each specific subclass of tumors. Accompanied by a growing number of clinical trials of molecular targeted drugs, diagnostic and prognostic biomarker development will be facilitated with special attention on study design and with new assay technologies specialized for archived fixed tissues. A new class of genomic information, microRNA dysregulation and epigenetic alterations, will provide insight for more precise understanding of disease mechanism and expand the opportunity of biomarker/therapeutic target discovery. These efforts will eventually enable personalized management of HCC. PMID:20175032

Hoshida, Yujin; Toffanin, Sara; Lachenmayer, Anja; Villanueva, Augusto; Minguez, Beatriz; Llovet, Josep M

2010-02-19

87

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.

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

88

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.

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

2013-01-01

89

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.

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

2012-01-01

90

Advances in Molecular Characterization and Targeted Therapy in Dermatofibrosarcoma Protuberans  

PubMed Central

The molecular pathogenesis of dermatofibrosarcoma protuberans (DFSP) involves distinctive rearrangement of chromosomes 17 and 22 leading to formation of the COL1A1-PDGFB fusion gene. The knowledge of molecular events underlying development of DFSP resulted in the implementation of targeted therapy with imatinib—a tyrosine kinase inhibitor (TKI), to the clinical practice. The striking efficacy of imatinib in advanced cases of DFSP has been demonstrated in a few clinical trials. Thus, imatinib is currently considered the gold standard in the treatment of inoperable and/or metastatic and/or recurrent cases of DFSP. Therapy with imatinib may potentially facilitate resection or decrease possible disfigurement related to radical surgical procedure. Following partial response on imatinib significant percentage of patients may be rendered free of the disease by surgery of the residual tumor.

Rutkowski, Piotr; Wozniak, Agnieszka; Switaj, Tomasz

2011-01-01

91

Advances in molecular modeling of human cytochrome p450 polymorphism.  

PubMed

Cytochrome P450 (CYP) is a supergene family of metabolizing enzymes involved in the phase I metabolism of drugs and endogenous compounds. CYP oxidation often leads to inactive drug metabolites or to highly toxic or carcinogenic metabolites involved in adverse drug reactions (ADR). During the last decade, the impact of CYP polymorphism in various drug responses and ADR has been demonstrated. Of the drugs involved in ADR, 56% are metabolized by polymorphic phase I metabolizing enzymes, 86% among them being CYP. Here, we review the major CYP polymorphic forms, their impact for drug response and current advances in molecular modeling of CYP polymorphism. We focus on recent studies exploring CYP polymorphism performed by the use of sequence-based and/or protein-structure-based computational approaches. The importance of understanding the molecular mechanisms related to CYP polymorphism and drug response at the atomic level is outlined. PMID:23856621

Martiny, Virginie Y; Miteva, Maria A

2013-07-13

92

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.

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

93

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

94

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

95

Advanced remote decontamination techniques reduce costs and radiation doses  

SciTech Connect

A highly contaminated cell in the Pacific Northwest Laboratory's (PNL) 324 Building Radiochemical Engineering Facilities was recently decontaminated using a series of remote and contact techniques. The approach used in decontaminating the cell was very successful: It resulted in an 87% lower radiation dose to workers and a cost saving of 39% compared with a hands-on procedure used in another cell 2 yr earlier. Eight cycles of remote decontamination, combining use of an alkaline cleaner foam spray and pressurized water rinse, preceded manned entry. Initial radiation readings in cell C, averaging 50 rad/h, were first reduced to {lt} 200 mrad/h using remote techniques. Contact decontamination was then permissible using ultrahigh-pressure water at 270 MPa, further reducing the average radiation level in the cell to {lt} 86 mrem/h. The radiation dose and the costs to achieve a 244-fold reduction in radiation contamination were 17.8 mrem/m{sup 2} and $1033/m{sup 2} of cell surface area. This paper is part of a larger effort sponsored by the U.S. Department of Energy's Surplus Facilities Management Program to clean out six radioactive cells and to dismantle PNL's pilot-scale radioactive liquid-fed ceramic melter. In this program, numerous other advanced techniques are being developed and are proving valuable, particularly in lowering radiation doses.

Katayama, Y.B.; Holton, L.K. Jr.; Buck, G.N.; Hutchens, J.F.; Culverhouse, M.S. (Pacific Northwest Lab., Richland, WA (US))

1991-07-01

96

Recent Advances in the Molecular Pathogenesis of Ewing's Sarcoma  

PubMed Central

Tumor development is a complex process resulting from interplay between mutations in oncogenes and tumor suppressors, host susceptibility factors, and cellular context. Great advances have been made by studying rare tumors with unique clinical, genetic, or molecular features. Ewing's sarcoma serves as an excellent paradigm for understanding tumorigenesis because it exhibits some very useful and important characteristics. For example, nearly all cases of Ewing's sarcoma contain the (11;22)(q24;q12) chromosomal translocation that encodes the EWS/FLI oncoprotein. Besides the t(11;22), however, many cases have otherwise simple karyotypes with no other demonstrable abnormalities. Furthermore, it appears that an underlying genetic susceptibility to Ewing's sarcoma, if it exists, must be rare. These two features suggest that EWS/FLI is the primary mutation that drives the development of this tumor. Finally, Ewing's sarcoma is an aggressive tumor that requires aggressive treatment. Thus, improved understanding of the pathogenesis of this tumor will not only be of academic interest, but may also lead to new therapeutic approaches for individuals afflicted with this disease. The purpose of this review is to highlight recent advances in understanding the molecular pathogenesis of Ewing's sarcoma, while considering the questions surrounding this disease that still remain and how this knowledge may be applied to developing new treatments for patients with this highly-aggressive disease.

Toomey, Elizabeth C.; Schiffman, Joshua D.; Lessnick, Stephen L.

2013-01-01

97

On The Use of Molecular Filter Based Techniques  

NASA Astrophysics Data System (ADS)

Techniques employing molecular filters have been introduced in a variety of flow diagnostic techniques by various research groups. The molecular filter is a cylindrical optical cell which contains a molecule with absorption lines within the frequency of the laser interrogating the flow field. The molecular filter is placed in front of the receiving optics to modify the recorded intensity based on the frequency of the scattered light. There are three techniques which are currently being developed at Rutgers University. The first is termed Planar Doppler Velocimetry (PDV) which can measure multiple velocity components in a plane. This technique has been used in small laboratory facilities, as well as applied to measure the velocity field around models tested in large wind tunnels with an accuracy better than 2 m/s. A second technique termed Filtered Rayleigh scattering (FRS) has been extended to measure the instantaneous two-dimensional temperature in combustion environments. FRS has the advantage over typical Rayleigh scattering since measurements can be made close to surfaces (within 10um) and in flames dominated by solid particles. FRS temperature measurements in a hydrogen/air flame were compared to CARS measurements suggesting that an accuracy better than 3% can be achieved. The third technique, termed Filtered Angularly Resolved Rayleigh Scattering (FARRS), allows the simultaneous measurement of instantaneous pressure, density, temperature, and velocity fluctuations. FARRS measurements of turbulence quantities in subsonic and supersonic jets have been conducted and the correlation between various quantities are currently being computed.

Elliott, Greg; Glumac, Nick; Carter, Campbell

1998-11-01

98

Advances in Velocimetry Techniques for Plasma Turbulence Studies  

NASA Astrophysics Data System (ADS)

The HOP-V (Hybrid OPtical-flow Velocimetry) code, developed for extracting time-resolved 2-D velocity maps from turbulence imaging diagnostics, combines optical-flow and local pattern-matching techniques to derive ``dense'' velocity fields at the full time resolution and a fraction of the spatial resolution of the underlying image frames, often tens of pixels per side and thousands of timepoints in duration, with resolution sufficient to resolve the relevant turbulent structures. Here we discuss recent advances in the techniques for extracting velocity fields, as well as a number of applications related to analysis of turbulence and its interaction with plasma flow. As part of this study, we have implemented a synthetic diagnostic (similar to the Gas Puff Imaging instrument) to analyze the output of the BOUT and SOLT edge turbulence codes, enabling direct comparison to the known plasma quantities from the simulation, in an attempt to define the connection between the observed velocities and underlying turbulent plasma behavior. In this talk, we discuss recent velocimetry analysis of both numerical simulations and experiments.

Munsat, T.; Sechrest, Y.

2010-11-01

99

Advanced nuclear analytical and related techniques for the growing challenges in nanotoxicology.  

PubMed

Manufactured nanomaterials with novel physicochemical properties are an important basis for nanosciences and related technologies. Nanotoxicology, aiming to understand the principles of interactions at the nano-bio interface and the relationship between the physicochemical properties of nanomaterials and their toxicological profiles, has become a new frontier in nanoscience. Nearly one decade of nanotoxicology research has shown that the interactions between nanomaterials and proteins, cells, animals, humans and the environment as well as the underlying mechanisms of toxicity for nanomaterials are remarkably complicated, requiring dedicated analytical methodology and tools. Because of their advantages of absolute quantification, high sensitivity, excellent accuracy and precision, low matrix effects and non-destructiveness, nuclear analytical techniques have been playing important roles in the study of nanotoxicology. A systematic summary and comprehensive review of the advanced nuclear analytical and related techniques in nanotoxicology is greatly needed. In this review article, we present a comprehensive overview of nuclear analytical techniques applied to the physicochemical characterization of nanomaterials, structural analysis of bio-nano interactions, visualization of nanomaterials in vitro, quantification of bio-distribution, bio-accumulation, and transformation of nanomaterials in vivo. As important complementary tools, optical imaging technologies are also highlighted. Future directions regarding advanced nuclear analytical approaches for nanotoxicology are also discussed. The rapid development of advanced light source-based techniques will enable new high-throughput screening techniques and provide high sensitivity with low detection limits, which are required for the distribution, imaging, and structural analysis of nanomaterials, and the molecular information of biomarkers for all aspects of nanotoxicology. PMID:23868609

Chen, Chunying; Li, Yu-Feng; Qu, Ying; Chai, Zhifang; Zhao, Yuliang

2013-07-18

100

Coal and Coal Constituent Studies by Advanced EMR Techniques  

SciTech Connect

Advanced electronic magnetic resonance (EMR) methods are used to examine properties of coals, chars, and molecular species related to constituents of coal. We have achieved substantial progress on upgrading the high field (HF) EMR (W-band, 95 GHz) spectrometers that are especially advantageous for such studies. Particularly, we have built a new second W-band instrument (Mark II) in addition to our Mark I. Briefly, Mark II features: (i) an Oxford custom-built 7 T superconducting magnet which is scannable from 0 to 7 T at up to 0.5 T/min; (ii) water-cooled coaxial solenoid with up to ±550 G scan under digital (15 bits resolution) computer control; (iii) custom-engineered precision feed-back circuit, which is used to drive this solenoid, is based on an Ultrastab 860R sensor that has linearity better than 5 ppm and resolution of 0.05 ppm; (iv) an Oxford CF 1200 cryostat for variable temperature studies from 1.8 to 340 K. During this grant period we have completed several key upgrades of both Mark I and II, particularly microwave bridge, W-band probehead, and computer interfaces. We utilize these improved instruments for HF EMR studies of spin-spin interaction and existence of different paramagnetic species in carbonaceous solids.

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

1998-03-31

101

Advances in Cardiovascular Molecular Imaging for Tracking Stem Cell Therapy  

PubMed Central

The high mortality rate associated with cardiovascular disease is partially due to the lack of proliferative cells in the heart. Without adequate repair following myocardial infarction, progressive dilation can lead to heart failure. Stem cell therapies present one promising option for treating cardiovascular disease, though the specific mechanisms by which they benefit the heart remain unclear. Before stem cell therapies can be used safely in human populations, their biology must be investigated using innovative technologies such as multi-modality molecular imaging. The present review will discuss the basic principles, labeling techniques, clinical applications, and drawbacks associated with four major modalities: radionuclide imaging, magnetic resonance imaging, bioluminescence imaging, and fluorescence imaging.

Ransohoff, Katherine J.; Wu, Joseph C.

2010-01-01

102

Characterising chromosome rearrangements: recent technical advances in molecular cytogenetics  

PubMed Central

Genomic rearrangements can result in losses, amplifications, translocations and inversions of DNA fragments thereby modifying genome architecture, and potentially having clinical consequences. Many genomic disorders caused by structural variation have initially been uncovered by early cytogenetic methods. The last decade has seen significant progression in molecular cytogenetic techniques, allowing rapid and precise detection of structural rearrangements on a whole-genome scale. The high resolution attainable with these recently developed techniques has also uncovered the role of structural variants in normal genetic variation alongside single-nucleotide polymorphisms (SNPs). We describe how array-based comparative genomic hybridisation, SNP arrays, array painting and next-generation sequencing analytical methods (read depth, read pair and split read) allow the extensive characterisation of chromosome rearrangements in human genomes.

Le Scouarnec, S; Gribble, S M

2012-01-01

103

Recent advances in the molecular basis of frontotemporal dementia  

PubMed Central

Frontotemporal dementia (FTD) is a clinical syndrome with heterogeneous molecular basis. Until recently, our knowledge was limited to a minority of cases associated with abnormalities of the tau protein or gene (MAPT). However, in 2006, mutations in progranulin (GRN) were discovered as another important cause of familial FTD. That same year, TAR DNA binding protein 43 (TDP-43) was identified as the pathological protein in the most common subtypes of FTD and ALS. Since then, significant efforts have been made to understand the normal functions and regulation of GRN and TDP-43 and their roles in neurodegeneration. More recently, other DNA/RNA binding proteins (FUS, EWS and TAF15) were identified as pathological proteins in most of the remaining cases of FTD. And just six months ago, abnormal expansion of a hexanucleotide repeat in C9ORF72 was found to be the most common genetic cause of both FTD and ALS. With this remarkable progress, it appears that all the common FTD-causing genes have now been discovered and the major pathological proteins identified. This review highlights recent advances in the molecular aspects of FTD, which will provide the basis for improved patient care through the future development of more targeted diagnostic tests and therapies.

Rademakers, Rosa; Neumann, Manuela; Mackenzie, Ian R. A.

2013-01-01

104

Removing baseline flame's spectrum by using advanced recovering spectrum techniques.  

PubMed

In this paper, a novel automated algorithm to estimate and remove the continuous baseline from measured flame spectra is proposed. The algorithm estimates the continuous background based on previous information obtained from a learning database of continuous flame spectra. Then, the discontinuous flame emission is calculated by subtracting the estimated continuous baseline from the measured spectrum. The key issue subtending the learning database is that the continuous flame emissions are predominant in the sooty regions, in absence of discontinuous radiation. The proposed algorithm was tested using natural gas and bio-oil flames spectra at different combustion conditions, and the goodness-of-fit coefficient (GFC) quality metric was used to quantify the performance in the estimation process. Additionally, the commonly used first derivative method (FDM) for baseline removing was applied to the same testing spectra in order to compare and to evaluate the proposed technique. The achieved results show that the proposed method is a very attractive tool for designing advanced combustion monitoring strategies of discontinuous emissions. PMID:22945158

Arias, Luis; Sbarbaro, Daniel; Torres, Sergio

2012-09-01

105

Pediatric Cardiopulmonary Resuscitation: Advances in Science, Techniques, and Outcomes  

PubMed Central

More than 25% of children survive to hospital discharge after in-hospital cardiac arrests, and 5% to 10% survive after out-of-hospital cardiac arrests. This review of pediatric cardiopulmonary resuscitation addresses the epidemiology of pediatric cardiac arrests, mechanisms of coronary blood flow during cardiopulmonary resuscitation, the 4 phases of cardiac arrest resuscitation, appropriate interventions during each phase, special resuscitation circumstances, extracorporeal membrane oxygenation cardiopulmonary resuscitation, and quality of cardiopulmonary resuscitation. The key elements of pathophysiology that impact and match the timing, intensity, duration, and variability of the hypoxic-ischemic insult to evidence-based interventions are reviewed. Exciting discoveries in basic and applied-science laboratories are now relevant for specific subpopulations of pediatric cardiac arrest victims and circumstances (eg, ventricular fibrillation, neonates, congenital heart disease, extracorporeal cardiopulmonary resuscitation). Improving the quality of interventions is increasingly recognized as a key factor for improving outcomes. Evolving training strategies include simulation training, just-in-time and just-in-place training, and crisis-team training. The difficult issue of when to discontinue resuscitative efforts is addressed. Outcomes from pediatric cardiac arrests are improving. Advances in resuscitation science and state-of-the-art implementation techniques provide the opportunity for further improvement in outcomes among children after cardiac arrest.

Topjian, Alexis A.; Berg, Robert A.; Nadkarni, Vinay M.

2009-01-01

106

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.

Morton, Penny E

2011-01-01

107

ADVANCED TECHNIQUES FOR RESERVOIR SIMULATION AND MODELING OF NONCONVENTIONAL WELLS  

SciTech Connect

Nonconventional wells, which include horizontal, deviated, multilateral and ''smart'' wells, offer great potential for the efficient management of oil and gas reservoirs. These wells are able to contact larger regions of the reservoir than conventional wells and can also be used to target isolated hydrocarbon accumulations. The use of nonconventional wells instrumented with downhole inflow control devices allows for even greater flexibility in production. Because nonconventional wells can be very expensive to drill, complete and instrument, it is important to be able to optimize their deployment, which requires the accurate prediction of their performance. However, predictions of nonconventional well performance are often inaccurate. This is likely due to inadequacies in some of the reservoir engineering and reservoir simulation tools used to model and optimize nonconventional well performance. A number of new issues arise in the modeling and optimization of nonconventional wells. For example, the optimal use of downhole inflow control devices has not been addressed for practical problems. In addition, the impact of geological and engineering uncertainty (e.g., valve reliability) has not been previously considered. In order to model and optimize nonconventional wells in different settings, it is essential that the tools be implemented into a general reservoir simulator. This simulator must be sufficiently general and robust and must in addition be linked to a sophisticated well model. Our research under this five year project addressed all of the key areas indicated above. The overall project was divided into three main categories: (1) advanced reservoir simulation techniques for modeling nonconventional wells; (2) improved techniques for computing well productivity (for use in reservoir engineering calculations) and for coupling the well to the simulator (which includes the accurate calculation of well index and the modeling of multiphase flow in the wellbore); and (3) accurate approaches to account for the effects of reservoir heterogeneity and for the optimization of nonconventional well deployment. An overview of our progress in each of these main areas is as follows. A general purpose object-oriented research simulator (GPRS) was developed under this project. The GPRS code is managed using modern software management techniques and has been deployed to many companies and research institutions. The simulator includes general black-oil and compositional modeling modules. The formulation is general in that it allows for the selection of a wide variety of primary and secondary variables and accommodates varying degrees of solution implicitness. Specifically, we developed and implemented an IMPSAT procedure (implicit in pressure and saturation, explicit in all other variables) for compositional modeling as well as an adaptive implicit procedure. Both of these capabilities allow for efficiency gains through selective implicitness. The code treats cell connections through a general connection list, which allows it to accommodate both structured and unstructured grids. The GPRS code was written to be easily extendable so new modeling techniques can be readily incorporated. Along these lines, we developed a new dual porosity module compatible with the GPRS framework, as well as a new discrete fracture model applicable for fractured or faulted reservoirs. Both of these methods display substantial advantages over previous implementations. Further, we assessed the performance of different preconditioners in an attempt to improve the efficiency of the linear solver. As a result of this investigation, substantial improvements in solver performance were achieved.

Louis J. Durlofsky; Khalid Aziz

2004-08-20

108

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

109

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

110

Petroleomics: advanced molecular probe for petroleum heavy ends.  

PubMed

To look into complex mixtures of petroleum heavy ends at the molecular level, ultra high-resolution mass spectrometry, i.e. resolving power > 50,000, is needed to resolve overlapping components for accurate determination of molecular composition of individual components. Recent progress in Fourier transform ion cyclotron resonance mass spectrometry (FT-ICR MS) incorporated with soft ionization techniques adaptable to liquid chromatography enables analysis of petroleum high ends, i.e., heavy oils, residua and asphaltenes. FT-ICR MS at the Future Fuels Institute of Florida State University and the National High Magnetic Field Laboratory (NHMFL) routinely provides 1,000,000 resolving power at 400 Da, with root mean square (rms) mass measurement accuracy between 30 and 500 ppb for 5000-30,000 identified species in a single mass spectrum. Phase correction of the detected ion signal increases resolving power 40-100%, improving mass accuracy up to twofold. Overlapping ionic species that differ in mass by as little as one electron mass (548 µDa) can be resolved. A database of more than 100,000 components of different elemental composition has been generated at NHMFL. PMID:21438082

Hsu, Chang S; Hendrickson, Christopher L; Rodgers, Ryan P; McKenna, Amy M; Marshall, Alan G

2011-04-01

111

Proposed Techniques for Determining the Relative Importance of the Advancement Qualifications.  

National Technical Information Service (NTIS)

This research report describes the data reduction and analysis phase of the proposed techniques for determining the relative importance of Navy advancement qualifications. The quantitative techniques are applied to the data collected through the Data Syst...

M. D. Callahan N. A. Hrutkay T. B. Turner A. J. Rose

1968-01-01

112

Recent advances in the molecular and cellular biology of bunyaviruses.  

PubMed

The family Bunyaviridae of segmented, negative-stranded RNA viruses includes over 350 members that infect a bewildering variety of animals and plants. Many of these bunyaviruses are the causative agents of serious disease in their respective hosts, and are classified as emerging viruses because of their increased incidence in new populations and geographical locations throughout the world. Emerging bunyaviruses, such as Crimean-Congo hemorrhagic fever virus, tomato spotted wilt virus and Rift Valley fever virus, are currently attracting great interest due to migration of their arthropod vectors, a situation possibly linked to climate change. These and other examples of continued emergence suggest that bunyaviruses will probably continue to pose a sustained global threat to agricultural productivity, animal welfare and human health. The threat of emergence is particularly acute in light of the lack of effective preventative or therapeutic treatments for any of these viruses, making their study an important priority. This review presents recent advances in the understanding of the bunyavirus life cycle, including aspects of their molecular, cellular and structural biology. Whilst special emphasis is placed upon the emerging bunyaviruses, we also describe the extensive body of work involving model bunyaviruses, which have been the subject of major contributions to our overall understanding of this important group of viruses. PMID:21865443

Walter, Cheryl T; Barr, John N

2011-08-24

113

Molecular imprinting: a dynamic technique for diverse applications in analytical chemistry.  

PubMed

Continuous advances in analyzing complex matrices, improving reliability and simplicity, and performing multiple simultaneous assays with extreme sensitivity are increasing. Several techniques have been developed for the quantitative assays of analytes at low concentrations (e.g., high-pressure liquid chromatography, gas chromatography, immunoassay and the polymerase chain reaction technique). To achieve highly specific and sensitive analysis, high affinity, stable, and specific recognition agents are needed. Although biological recognition agents are very specific and sensitive they are labile and/or have a low density of binding sites. During the past decade molecular imprinting has emerged as an attractive and highly accepted tool for the development of artificial recognition agents. Molecular imprinting is achieved by the interaction, either noncovalent or covalent, between complementary groups in a template molecule and functional monomer units through polymerization or polycondensation. These molecularly imprinted polymers have been widely employed for diverse applications (e.g., in chromatographic separation, drug screening, chemosensors, catalysis, immunoassays etc.) owing to their specificity towards the target molecules and high stability against physicochemical perturbations. In this review the advantages, applications, and recent developments in molecular imprinting technology are highlighted. PMID:15480581

Kandimalla, Vivek Babu; Ju, Hunagxian

2004-10-08

114

Miniaturization of molecular biological techniques for gene assay.  

PubMed

The rapid diagnosis of various diseases is a critical advantage of many emerging biomedical tools. Due to advances in preventive medicine, tools for the accurate analysis of genetic mutation and associated hereditary diseases have attracted significant interests in recent years. The entire diagnostic process usually involves two critical steps, namely, sample pre-treatment and genetic analysis. The sample pre-treatment processes such as extraction and purification of the target nucleic acids prior to genetic analysis are essential in molecular diagnostics. The genetic analysis process may require specialized apparatus for nucleic acid amplification, sequencing and detection. Traditionally, pre-treatment of clinical biological samples (e.g. the extraction of deoxyribonucleic acid (DNA) or ribonucleic acid (RNA)) and the analysis of genetic polymorphisms associated with genetic diseases are typically a lengthy and costly process. These labor-intensive and time-consuming processes usually result in a high-cost per diagnosis and hinder their practical applications. Besides, the accuracy of the diagnosis may be affected owing to potential contamination from manual processing. Alternatively, due to significant advances in micro-electro-mechanical-systems (MEMS) and microfluidic technology, there are numerous miniature systems employed in biomedical applications, especially for the rapid diagnosis of genetic diseases. A number of advantages including automation, compactness, disposability, portability, lower cost, shorter diagnosis time, lower sample and reagent consumption, and lower power consumption can be realized by using these microfluidic-based platforms. As a result, microfluidic-based systems are becoming promising platforms for genetic analysis, molecular biology and for the rapid detection of genetic diseases. In this review paper, microfluidic-based platforms capable of identifying genetic sequences and diagnosis of genetic mutations are surveyed and reviewed. Some critical issues with the use of microfluidic-based systems for diagnosis of genetic diseases are also highlighted. PMID:20390199

Lien, Kang-Yi; Lee, Gwo-Bin

2010-04-14

115

Advanced diagnostic\\/prognostic reasoning and evidence transformation techniques for improved avionics maintenance  

Microsoft Academic Search

Techniques used in the design and implementation of modern avionics suggest an opportunity to re-examine the maintenance and repair process for current and future systems. The authors have developed a framework with automated evidence collection, data representation and storage, and, advanced automated reasoning techniques to implement within an avionics health management system. This paradigm shift approach utilizes advanced capture and

Carl S. Byington; P. W. Kalgren; Brian K. Dunkin; Bryan P. Donovan

2004-01-01

116

Evaluation of Innovative Vessel Inspection Techniques. Phase II. Advanced Technology.  

National Technical Information Service (NTIS)

This report provides the results of the effort to evaluate marine inspection equipment and techniques for use by Coast Guard marine inspectors. Previous reports identified many potentially useful techniques that could enhance inspections both by providing...

M. J. Goodwin K. A. Hansen

1995-01-01

117

NIH Funds Synchrotron Beamlines to Advance Studies of Molecular Structures  

Cancer.gov

To advance structural studies of biological molecules, the National Institute of General Medical Sciences (NIGMS) and the NCI are supporting the design and construction of a user facility consisting of three new beamlines at Argonne National Laboratory's Advanced Photon Source, the newest and most advanced synchrotron in the country.

118

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

119

Colon polypectomy: a review of routine and advanced techniques.  

PubMed

The value of performing comprehensive screening colonoscopy with complete colon polypectomy is widely accepted. Colon cancer is a significant cause of worldwide mortality and prospective studies have proven that colonoscopic polypectomy reduces both the incidence and mortality related to this disease. Over the past few decades the array of instruments and techniques have greatly expanded to assist with the safe endoscopic removal of colon polyps. This article will review the published literature regarding efficacy and safety of standard polypectomy techniques such as snare polypectomy, electrocautery, and endoscopic mucosal resection along with newer techniques such as endoscopic submucosal dissection and combined laparoscopic techniques. PMID:23948754

Kedia, Prashant; Waye, Jerome D

2013-09-01

120

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

121

Advanced automatic test pattern generation and redundancy identification techniques  

Microsoft Academic Search

Based on the sophisticated strategies used in the automatic test pattern generation system SOCRATES, the authors present several concepts aiming at a further improvement and acceleration of the deterministic test pattern generation and redundancy identification process. In particular, they describe an improved implication procedure and an improved unique sensitization procedure. Both procedures significantly advance the deterministic test pattern generation and

Michael H. Schulz; Elisabeth Auth

1988-01-01

122

Parallel adaptive tetrahedral mesh generation by the advancing front technique  

Microsoft Academic Search

A parallel adaptive tetrahedral mesh generation program using the advancing front method is described. The problem domain is initially defined by a course background mesh of tetrahedral elements which forms the input for finite element analysis and from which adaptive parameters are calculated. Parallel adaptive mesh generation is then carried out by dividing the background mesh into subdomains and refining

J. K. Wilson; B. H. V. Topping

1998-01-01

123

Bricklaying Curriculum: Advanced Bricklaying Techniques. Instructional Materials. Revised.  

ERIC Educational Resources Information Center

|This curriculum guide is designed to assist bricklaying instructors in providing performance-based instruction in advanced bricklaying. Included in the first section of the guide are units on customized or architectural masonry units; glass block; sills, lintels, and copings; and control (expansion) joints. The next two units deal with cut,…

Turcotte, Raymond J.; Hendrix, Laborn J.

124

Investigation of PACVD protective coating processes using advanced diagnostics techniques  

SciTech Connect

Objective is to understand the mechanisms governing nonequilibrium plasma atomistic or molecular deposition of hard face coatings. Laser diagnostic methods include coherent anti-Stokes Raman spectroscopy (CARS) and laser-induced fluorescence. TiB[sub 2] and diamonds were used as the hard face coating materials. Diborane was used as precursor to TiB[sub 2].

Roman, W.C.

1993-05-07

125

Molecular imaging suggests efficacy of bevacizumab beyond the second line in advanced colorectal cancer patients.  

PubMed

We report the clinical history of a female affected by advanced colorectal cancer (CRC). The patient was treated with five subsequent therapeutic schedules (FOLFIRI, FOLFOXIRI, FOLFIRI, FOLFOX4, FOLFOX4 plus cetuximab) because of the progression of the disease. The sixth treatment was bevacizumab in combination with 5-fluorouracil and irinotecan (FOLFIRI). The CT scan and the FDG-PET/CT performed 3 months after the beginning of the treatment showed that some, even if not all, lesions had a reduction of both size and metabolic activity. After the second revaluation the disease progressed. This short report suggests that the response of CRC to antiangiogenetic therapy may also occur after several unsuccessful antineoplastic treatments. Different biological features may explain the nonhomogeneous objective response of the metastatic lesions. Molecular imaging techniques seem to be mandatory in the era of tailored therapy since it is useful to have an in vivo 'biological picture' of the neoplastic disease. PMID:18824847

Brandi, G; Nannini, M; Pantaleo, M A; Fanello, S; Farsad, M; Fanti, S; Ercolani, G; Maleddu, A; Di Battista, M; Biasco, G

2008-09-29

126

Advanced digital techniques for high bandwidth chirp generation  

NASA Astrophysics Data System (ADS)

A brief summary of important digital chirp generation (DCG) techniques is provided, with emphasis on two complementary methods - systolic and parallel digital chirp generation. These techniques provide an order of magnitude improvement in performance when compared with conventional digital chirp generation techniques implemented on the same technology. When implemented on the same technology, the systolic DCG yields a threefold improvement in performance. If used in conjunction with the parallel DCG, an order of magnitude performance is readily achievable. Combining the systolic DCG with the parallel method and using the chirp generator FPGA devices with a video digital to analog converter enables sample rates of 160 MHZ to be produced.

Parkes, S. M.

127

A temperature control technique for nonequilibrium molecular simulation  

NASA Astrophysics Data System (ADS)

We describe a dynamical approach to thermal regulation in molecular dynamics. Temperature is moderated by a control law and an additional variable, as in Nosé dynamics, but whose influence on the system decreases as the system approaches equilibrium. This device enables approximation of microcanonical averages and autocorrelation functions consistent with a given target temperature. Moreover, we demonstrate that the suggested technique is effective for the control of heat dissipation in a nonequilibrium setting, first by showing that the temperature control correctly regulates heat introduced by a rapid change to the system, and then by studying the slow relaxation of vibrational degrees of freedom (e.g., due to bonded atoms) in a solvent bath.

Leimkuhler, Ben; Legoll, Frédéric; Noorizadeh, Emad

2008-02-01

128

Advanced Techniques for Power System Identification from Measured Data  

Microsoft Academic Search

Time-synchronized measurements provide rich information for estimating a power-system's electromechanical modal properties via advanced signal processing. This information is becoming critical for the improved operational reliability of interconnected grids. A given mode's properties are described by its frequency, damping, and shape. Modal frequencies and damping are useful indicators of power-system stress, usually declining with increased load or reduced grid capacity.

John W. Pierre; Richard Wies; Daniel Trudnowski

2008-01-01

129

IMPROVE: Advanced Displays and Interaction Techniques for Collaborative Design Review  

Microsoft Academic Search

In this paper we present evaluation results of an innovative application designed to make collaborative design review in the\\u000a architectural and automotive domain more effective. Within IMPROVE, a European research project in the area of advanced displays,\\u000a we are combining high resolution multi-tile displays, TabletPCs and head-mounted displays with innovative 2D and 3D Interaction\\u000a Paradigms to better support collaborative mobile

Pedro Santos; André Stork; Thomas Gierlinger; Alain Pagani; Bruno Araújo; Ricardo Jota; Luis Bruno; Joaquim A. Jorge; João Madeiras Pereira; Martin Witzel; Giuseppe Conti; Raffaele De Amicis; Iñigo Barandarian; Céline Paloc; Maylu Hafner; Don Mcintyre

2007-01-01

130

Detailed study of potassium solvation using molecular dynamics techniques  

SciTech Connect

Molecular dynamics simulations are carried out to examine the solvation properties and the ion-solvation shell exchange process of the K{sup +} ion in liquid water, chloroform, and carbon tetrachloride. The solvent molecules are found to form well-defined solvation shells around the K{sup +} ion and show a preferred orientational order toward the ion. The induced dipole moment distribution of K{sup +} becomes broader and shifts to a larger average value from chloroform to carbon tetrachloride to water. It is observed that the K{sup +} ion diffuses more rapidly in the aqueous phase than in liquid chloroform and carbon tetrachloride. The authors have also evaluated both ion and first solvent shell velocity autocorrelation functions and the residence time autocorrelation functions for the ion in water, chloroform, and carbon tetrachloride. The residence time is found to be 9.4 ps for water and about 30 ps for both chloroform and carbon tetrachloride. By use of a constrained molecular dynamics technique, the first solvation shell exchange process is investigated. It is found that an estimate using equilibrium solvation and classical transition-state theory overestimates the dissociation rate o the K{sup +} ion. Including the dynamical effects using Grote-Hynes theory yields more accurate dissociation rates.

Chang, T.M.; Dang, L.X. [Pacific Northwest National Lab., Richland, WA (United States). Environmental Molecular Sciences Lab.

1999-06-03

131

Modeling large RNAs and ribonucleoprotein particles using molecular mechanics techniques.  

PubMed Central

There is a growing body of low-resolution structural data that can be utilized to devise structural models for large RNAs and ribonucleoproteins. These models are routinely built manually. We introduce an automated refinement protocol to utilize such data for building low-resolution three-dimensional models using the tools of molecular mechanics. In addition to specifying the positions of each nucleotide, the protocol provides quantitative estimates of the uncertainties in those positions, i.e., the resolution of the model. In typical applications, the resolution of the models is about 10-20 A. Our method uses reduced representations and allows us to refine three-dimensional structures of systems as big as the 16S and 23S ribosomal RNAs, which are about one to two orders of magnitude larger than nucleic acids that can be examined by traditional all-atom modeling methods. Nonatomic resolution structural data--secondary structure, chemical cross-links, chemical and enzymatic footprinting patterns, protein positions, solvent accessibility, and so on--are combined with known motifs in RNA structure to predict low-resolution models of large RNAs. These structural constraints are imposed on the RNA chain using molecular mechanics-type potential functions with parameters based on the quality of experimental data. Surface potential functions are used to incorporate shape and positional data from electron microscopy image reconstruction experiments into our models. The structures are optimized using techniques of energy refinement to get RNA folding patterns. In addition to providing a consensus model, the method finds the range of models consistent with the data, which allows quantitative evaluation of the resolution of the model. The method also identifies conflicts in the experimental data. Although our protocol is aimed at much larger RNAs, we illustrate these techniques using the tRNA structure as an example and test-bed. Images FIGURE 7 FIGURE 8

Malhotra, A; Tan, R K; Harvey, S C

1994-01-01

132

Advanced Techniques for the Reduction of Geodetic Secor Observations.  

National Technical Information Service (NTIS)

Techniques developed earlier (see AD-425 480) for the self-calibration of tracking systems are applied to geodetic SECOR system. An error model for Geodetic SECOR is developed, special attention being devoted to inospheric refraction. The rigorous adjustm...

D. C. Brown

1966-01-01

133

Molecular Analysis of Microbial Diversity in Advanced Caries  

Microsoft Academic Search

Received 13 May 2004\\/Returned for modification 15 July 2004\\/Accepted 24 September 2004 Real-time PCR analysis of the total bacterial load in advanced carious lesions has shown that the total load exceeds the number of cultivable bacteria. This suggests that an unresolved complexity exists in bacteria associated with advanced caries. In this report, the profile of the microflora of carious dentine

Kim-Ly Chhour; Mangala A. Nadkarni; Roy Byun; F. Elizabeth Martin; Nicholas A. Jacques; Neil Hunter

2005-01-01

134

Shoe Signature Monitoring for Advanced Running Technique (P145)  

Microsoft Academic Search

An athlete and support team will utilise whatever tools are at their disposal to help ‘measure’ the athletic ability and develop\\u000a it further. However, assessment of the athletic motion technique and propulsion mechanics is usually limited to a combination\\u000a of indirect techniques (visual, high-speed video etc.) and may include some direct measurement of foot-surface contact forces\\u000a or pressures in a

C Young; P. R. Fleming; S Dixon; M. J. Carré

135

Advanced millimeter-wave security portal imaging techniques  

NASA Astrophysics Data System (ADS)

Millimeter-wave (mm-wave) imaging is rapidly gaining acceptance as a security tool to augment conventional metal detectors and baggage x-ray systems for passenger screening at airports and other secured facilities. This acceptance indicates that the technology has matured; however, many potential improvements can yet be realized. The authors have developed a number of techniques over the last several years including novel image reconstruction and display techniques, polarimetric imaging techniques, array switching schemes, and high-frequency high-bandwidth techniques. All of these may improve the performance of new systems; however, some of these techniques will increase the cost and complexity of the mm-wave security portal imaging systems. Reducing this cost may require the development of novel array designs. In particular, 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. Highfrequency, high-bandwidth designs are difficult to achieve with conventional mm-wave electronic devices, and RF photonic devices may be a practical alternative. In this paper, the mm-wave imaging techniques developed at PNNL are reviewed and the potential for implementing RF photonic mm-wave array designs is explored.

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

2012-02-01

136

Collected Bibliography of Clinical Advances in Sickle Cell Disease Based on the Murayama Molecular Hypothesis.  

National Technical Information Service (NTIS)

The bibliography makes available all scientific communications dealing with diagnostic and therapeutic advances in sickle cell disease derived from the Murayama hypothesis for the molecular events involved in the sickling of a hemoglobin S red cell.

F. R. Camp R. M. Nalbandian

1972-01-01

137

Advancing the frontiers in nanocatalysis, biointerfaces, and renewable energy conversion by innovations of surface techniques.  

PubMed

The challenge of chemistry in the 21st century is to achieve 100% selectivity of the desired product molecule in multipath reactions ("green chemistry") and develop renewable energy based processes. Surface chemistry and catalysis play key roles in this enterprise. Development of in situ surface techniques such as high-pressure scanning tunneling microscopy, sum frequency generation (SFG) vibrational spectroscopy, time-resolved Fourier transform infrared methods, and ambient pressure X-ray photoelectron spectroscopy enabled the rapid advancement of three fields: nanocatalysts, biointerfaces, and renewable energy conversion chemistry. In materials nanoscience, synthetic methods have been developed to produce monodisperse metal and oxide nanoparticles (NPs) in the 0.8-10 nm range with controlled shape, oxidation states, and composition; these NPs can be used as selective catalysts since chemical selectivity appears to be dependent on all of these experimental parameters. New spectroscopic and microscopic techniques have been developed that operate under reaction conditions and reveal the dynamic change of molecular structure of catalysts and adsorbed molecules as the reactions proceed with changes in reaction intermediates, catalyst composition, and oxidation states. SFG vibrational spectroscopy detects amino acids, peptides, and proteins adsorbed at hydrophobic and hydrophilic interfaces and monitors the change of surface structure and interactions with coadsorbed water. Exothermic reactions and photons generate hot electrons in metal NPs that may be utilized in chemical energy conversion. The photosplitting of water and carbon dioxide, an important research direction in renewable energy conversion, is discussed. PMID:19919130

Somorjai, Gabor A; Frei, Heinz; Park, Jeong Y

2009-11-25

138

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

139

The integrated dynamic exercise advancement system technique for progressing functional closed kinetic chain rehabilitation programs.  

PubMed

Graded exercise progressions are necessary during the rehabilitation process. We developed the Integrated Dynamic Exercise Advancement System (IDEAS) to fill this void. There appears to be a lack of progression/advancement systems for closed kinetic chain exercises, even though the IDEAS technique for advancing closed chain activities is comprised of two phases: preparing a safe environment and advancing the exercise. Phase one includes a conceptual checklist to assess the safety of the environment. Phase two is a six-step process that challenges each plane of motion by adding speed, workload, external stimuli, and terrain changes. The IDEAS technique is presented to safely prepare an environment and help clinicians to put thought into advancing an exercise program. The IDEAS technique is suggested for use in other arenas such as strength and conditioning. PMID:16558291

Pitney, W A; Bunton, E E

1994-12-01

140

Advanced techniques in vibrometry by using spatial light modulators  

NASA Astrophysics Data System (ADS)

Vibrometry is a modern contactless measurement technique to analyze vibrations in different applications. It is extremely important for industry and research. Since spatial light modulators (SLM) have been developed, new techniques in vibrometry are possible. This paper presents two applications which use the SLM as actor instead of a galvanic mirror. Both techniques modify the phase of the wave front of a laser beam by using an SLM. On the one hand, it allows varying the focus plane and repositioning of a spot without any mechanical device. For that, special patterns have to be written to the SLM. On the other hand, overlay patterns can be used to reduce speckle drop-outs nearly without changing position and focus of the spot. For both applications an optimized signal level is the key to get sufficient results in a rougher environment.

Mayer, S.; Tibken, B.; Rembe, C.

2012-06-01

141

Application of Active Learning Techniques to an Advanced Course  

NASA Astrophysics Data System (ADS)

The New Faculty Workshop provided a wealth of techniques as well as an overriding philosophy for the teaching of undergraduate Physics and Astronomy courses. The focus of the workshop was active learning, summarized in ``Learner-Centered Astronomy Teaching" by Slater & Adams: it's not what you do in class that matters, it's what the students do. Much of the specific focus of the New Faculty Workshop is on teaching the large, introductory Physics classes that many of the faculty present are sure to teach, both algebra-based and calculus-based. Many of these techniques apply directly and with little modification to introductory Astronomy courses. However, little direct attention is given to upper-division undergraduate, or even graduate, courses. In this presentation, I will share my experience in attempting to apply some of the techniques discussed at the New Faculty Workshop to an upper-division course in Galactic Astrophysics at Vanderbilt University during the Spring semester of 2004.

Knop, R. A.

2004-05-01

142

Molecularly imprinted materials as advanced excipients for drug delivery systems  

Microsoft Academic Search

The application of the molecular imprinting technology in the design of new drug delivery systems (DDS) and devices useful in closely related fields, such as diagnostic sensors or biological traps, is receiving increasing attention. Molecular imprinting technology can provide polymeric materials with the ability to recognize specific bioactive molecules and with a sorption\\/release behaviour that can be made sensitive to

Carmen Alvarez-Lorenzo; Angel Concheiro

2006-01-01

143

Advance of molecular marker application in the tobacco research  

Microsoft Academic Search

Tobacco (Nicotiana spp.) is one of the most important commercial crops in the world. During the last two decades, molecular markers have entered the scene of genetic improvement in different fields of agricultural research. The principles and characteristics of several molecular markers such as RFLP, RAPD, AFLP, microsatellites and minisatellites applied in tobacco genetics and breeding were reviewed. The application

X. Z. Liu; H. Y. Zhang

144

Advancing weatherization performance: Measured results from the North Carolina field test of an advanced measure selection technique  

SciTech Connect

The field performance of weatherizations based on a newly-developed advanced residential energy conservation measure selection technique was tested alongside current Retro-Tech-based weatherizations in North Carolina. The two weatherization approaches were compared based on implementation ease, measures installed, labor and cost requirements, and energy savings achieved. One-hundred twenty low-income, single-family households served by three different weatherization agencies participated in the field test which was conducted between June 1989 and August 1991. Average heating energy savings were 33% for weatherizations based on the new technique and 23% for Retro-Tech-based weatherizations. Weatherizations based on the new technique achieved 43% more heating energy savings, cost around 10% less at two weatherization agencies and considerably more at the third, and were near equivalent in labor requirements. Major findings from the study include: (1) the advanced audit will install some measures in near identical quantities as Retro-Tech-based weatherizations and others in dramatically different quantities, (2) the advanced audit can significantly increase heating energy savings, (3) blower-door-directed air sealing can more than double the air leakage reductions achieved from standard air sealing techniques, (4) North Carolina low-income houses have much higher average leakage rates than similar New York houses but can be sealed as well or better, and (5) using the advanced audit will not increase weatherization costs and may actually lower costs for most weatherization agencies.

Sharp, T.R.

1993-07-01

145

Ultrasmall volume molecular isothermal amplification in microfluidic chip with advanced surface processing  

Microsoft Academic Search

In this paper, we developed a metal micro-fluidic chip with advanced surface processing for ultra-small volume molecular isothermal amplification. This method takes advantages of the nucleic acid amplification with good stability and consistency, high sensitivity about 31 genomic DNA copies and bacteria specific gene identification. Based on the advanced surface processing, the bioreaction assays of nucleic acid amplification was dropped

Guoliang Huang; Li Ma; Xiaoyong Yang; Xu Yang

2011-01-01

146

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

147

Advanced system identification techniques for wind turbine structures with special emphasis on modal parameters.  

National Technical Information Service (NTIS)

The goal of this research is to develop advanced system identification techniques that can be used to accurately measure the frequency response functions of a wind-turbine structure immersed in wind noise. To allow for accurate identification, the authors...

J. T. Bialasiewicz

1995-01-01

148

Advanced automatic test pattern generation techniques for path delay faults  

Microsoft Academic Search

Based on the sophisticated techniques applied in the automatic test pattern generation system SOCRATES, the authors present the extension of SOCRATES to test generation for path delay faults. In particular, they propose a ten-valued logic and describe the corresponding implication and path sensitization procedures in detail. After discussing an extended multiple backtrace procedure, which has been developed specifically to meet

Michael H. Schulz; Karl Fuchs; Franz Fink

1989-01-01

149

Recent Advances in Techniques for Hyperspectral Image Processing  

Microsoft Academic Search

Imaging spectroscopy, also known as hyperspectral imaging, has been transformed in less than thirty years from being a sparse research tool into a commodity product available to a broad user community. Currently, there is a need for standardized data processing techniques able to take into account the special properties of hyperspec- tral data. In this paper, we provide a seminal

A. Plaza; J. A. Benediktsson; J. Boardman; J. Brazile; L. Bruzzone; G. Camps-Valls; J. Chanussot; M. Fauvel; P. Gamba; A. Gualtieri; M. Marconcini; J. C. Tilton; G. Trianni

2007-01-01

150

Recent advances in techniques for hyperspectral image processing  

Microsoft Academic Search

Imaging spectroscopy, also known as hyperspectral imaging, has been transformed in less than 30 years from being a sparse research tool into a commodity product available to a broad user community. Currently, there is a need for standardized data processing techniques able to take into account the special properties of hyperspectral data. In this paper, we provide a seminal view on

Antonio Plaza; Jon Atli Benediktsson; Joseph W. Boardman; Gustavo Camps-Valls; Lorenzo Bruzzone; Jocelyn Chanussot; Mathieu Fauvel; Paolo Gamba; Anthony Gualtieri; Mattia Marconcini; James C. Tilton; Giovanna Trianni

2009-01-01

151

Advances in seismic interpretation using new volume visualization techniques  

Microsoft Academic Search

s the use of 3D seismic interpretation continues to become part of the main stream work process with the industry, visualization techniques also continue to evolve as software and hardware improves. In the past 10 years, volume rendering tools have been progres- sively adopted by the geophysical community as the emer- gence of high-end graphics workstations with 3D texture capabilities

Laurent Castanie; Fabien Bosquet; Bruno Levy

152

Advancing operations management theory using exploratory structural equation modelling techniques  

Microsoft Academic Search

The structural equation modelling (SEM) technique has been touted as a useful tool for tightening links between theoretical and empirical operations management (OM) research. Despite SEM's increasing prominence in the field, leading scholars continue to call for a deeper infusion of theory into empirical OM research. To strengthen ties between theory and analysis in OM research, this study evaluates previous

Nicholas Roberts; Jason Bennett Thatcher; Varun Grover

2010-01-01

153

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

154

ADVANCED SAFETY ENGINEERING USING COMPOSITIONAL ANALYSIS AND OPTIMISATION TECHNIQUES  

Microsoft Academic Search

Increasing complexity in computer technology questions the applicability of classical safety analysis techniques on new designs. As new technologies introduce complex failure modes, the classical manual analysis of critical systems becomes increasingly more difficult and error prone. To address these difficulties, we have developed two computerised tools that simplify aspects of the safety engineering process. The first tool largely automates

Yiannis Papadopoulos; Christian Grante; Wenhua Zeng

155

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

Microsoft Academic Search

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

C. T. Chu; Jay Chu; Haixing Zheng

1995-01-01

156

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

Microsoft Academic Search

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

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

2005-01-01

157

Overview of advanced structural and reliability techniques for optimum design of fixed offshore platforms  

Microsoft Academic Search

The paper addresses the increasing use of advanced structural and reliability techniques in design optimisation of fixed offshore platforms. Recent changes in regulatory and contract practices within the offshore industry coupled with developments in structural and reliability methods and increased hardware capacity create a suitable framework for increased design optimisation. The paper examines the current impact of advanced structural analysis

Toula Onoufriou

1997-01-01

158

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.

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

2010-01-01

159

Tagging and Purifying Proteins to Teach Molecular Biology and Advanced Biochemistry  

ERIC Educational Resources Information Center

|Two distinct courses, "Molecular Biology" taught by the Biology Department and "Advanced Biochemistry" taught by the Chemistry Department, complement each other and, when taught in a coordinated and integrated way, can enhance student learning and understanding of complex material. "Molecular Biology" is a comprehensive lecture-based course with…

Roecklein-Canfield, Jennifer A.; Lopilato, Jane

2004-01-01

160

Recent advances in molecular epidemiology and detection of Taylorella equigenitalis associated with contagious equine metritis (CEM)  

Microsoft Academic Search

In the present review article, recent molecular advances relating to studies with Taylorella equigenitalis, as well as the recently described second species of the genus Taylorella, namely Taylorella asinigenitalis, have been described. Molecular genotyping of T. equigenitalis strains by pulsed-field gel electrophoresis (PFGE) after digestion with the suitable restriction enzyme(s) enabled the effective discrimination of strains, thus allowing the examination

Motoo Matsuda; John E Moore

2003-01-01

161

Computational ghost imaging: advanced compressive sensing (CS) technique  

NASA Astrophysics Data System (ADS)

A novel efficient variational technique for speckle imaging is discussed. It is developed with the main motivation to filter noise, to wipe out the typical diffraction artifacts and to achieve crisp imaging. A sparse modeling is used for the wave field at the object plane in order to overcome the loss of information due to the ill-posedness of forward propagation image formation operators. This flexible and data adaptive modeling relies on the recent progress in sparse imaging and compressive sensing (CS). Being in line with the general formalism of CS, we develop an original approach to wave field reconstruction.7 In this paper we demonstrate this technique in its application for computational amplitude ghost imaging (GI), where a spatial light modulator (SLM) is used in order to generate a speckle wave field sensing a transmitted mask object.

Katkovnik, Vladimir; Astola, Jaakko

162

Characterization of PTFE Using Advanced Thermal Analysis Techniques  

NASA Astrophysics Data System (ADS)

Polytetrafluoroethylene (PTFE) is a synthetic fluoropolymer used in numerous industrial applications. It is often referred to by its trademark name, Teflon. Thermal characterization of a PTFE material was carried out using various thermal analysis and thermophysical properties test techniques. The transformation energetics and specific heat were measured employing differential scanning calorimetry. The thermal expansion and the density changes were determined employing pushrod dilatometry. The viscoelastic properties (storage and loss modulus) were analyzed using dynamic mechanical analysis. The thermal diffusivity was measured using the laser flash technique. Combining thermal diffusivity data with specific heat and density allows calculation of the thermal conductivity of the polymer. Measurements were carried out from - 125 °C up to 150 °C. Additionally, measurements of the mechanical properties were carried out down to - 170 °C. The specific heat tests were conducted into the fully molten regions up to 370 °C.

Blumm, J.; Lindemann, A.; Meyer, M.; Strasser, C.

2010-10-01

163

Advances in epidemiology survey methodology and techniques in schistosomiasis  

PubMed Central

Quantitative techniques are now recognized to contribute to the validity and comparability of data from epidemiological studies in schistosomiasis. These methods have been developed and tested in field investigations in areas where Schistosoma mansoni is endemic and, to a lesser extent, S. haematobium endemic areas. Carefully planned epidemiological investigations using standardized and quantitative methods have contributed to our understanding of the relationships between intensity of infection and morbidity, as well as to the development of improved control strategies relevant to these areas. This article reviews the newer parasitological techniques, methods of morbidity assessment, and data analysis procedures employed in current epidemiological studies in schistosomiasis, as well as the analytical questions involved in research on the epidemiology of schistosomiasis.

Mott, K. E.; Cline, B. L.

1980-01-01

164

Role of advances in chromatographic techniques in phytochemistry.  

PubMed

Chromatography is the lynchpin of phytochemistry and is the key to obtaining pure compounds for structure elucidation, for pharmacological testing or for development into therapeuticals. It also plays a fundamental role as an analytical technique for quality control and standardisation of phytotherapeuticals. Although liquid chromatography is barely 100 years old, an extraordinary variety of instrumental and ancillary equipment is available, notably in the domain of high-performance liquid chromatography. It is impossible to touch all areas of chromatography in such a review but certain areas are worthy of mention: HPLC, HPTLC, UPLC and countercurrent chromatography. Another important addition has been the development of hyphenated techniques involving HPLC: LC/UV, LC/MS, LC/MS(n) and LC/NMR. These are indispensable nowadays for the early detection and identification of compounds in crude plant extracts. PMID:17931672

Marston, Andrew

2007-11-01

165

Thin-film growth and patterning techniques for small molecular organic compounds used in optoelectronic device applications.  

PubMed

Rapid advances in research and development in organic electronics have resulted in many exciting discoveries and applications, including organic light-emitting devices for information display and illumination, solar cells, photodetectors, chemosensors, and logic. Organic optoelectronic materials are broadly classified as polymeric or small molecular. For the latter category, solvent-free deposition techniques are generally preferred to form well-defined interfaces and improve device performance. This article reviews several deposition and patterning methods for small molecular thin films and devices, including organic molecular beam deposition, vacuum thermal evaporation, organic vapor phase deposition, and organic vapor jet printing, and compares them to several other methods that have been proposed recently. We hope this review provides a compact but informative summary of the state of the art in organic device processing and addresses the various techniques' governing physical principles. PMID:23540286

Biswas, Shaurjo; Shalev, Olga; Shtein, Max

2013-03-27

166

Advances on special structure drilling development techniques in Shengli Oilfield  

Microsoft Academic Search

Shengli Oilfield has developed the reservoir engineering design and drilling-completion-production techniques of special structure drilling for reservoirs with bottom water, fault block, heavy oil, unconformity etc, and drilled different types of wells including horizontal well, sidetracked well, extended reach well, multi-lateral horizontal well and so on. There are 586 different horizontal wells in 181 reservoirs of different types, and 742

Ying-jie ZHOU

2008-01-01

167

Advanced gain-scheduling techniques for uncertain systems  

Microsoft Academic Search

The paper is concerned with the design of gain-scheduled controllers for linear parameter-varying systems. Two alternative LMI characterizations are investigated. Both characterizations are amenable to a finite number of LMI conditions either via a gridding of the parameter range or via grid-free techniques which rely on multi-convexity concepts. Practicality and implementation issues are discussed and examples are provided

Pierre Apkarian; Richard J. Adams

1997-01-01

168

Sickle Cell Disease: Clinical Advances by the Murayama Molecular Hypothesis.  

National Technical Information Service (NTIS)

A comprehensive review of the scope and thrust of clinical gains, both diagnostic and therapeutic, made in sickle cell disease as a result of analytical, deductive, and inferential extensions of the modified Murayama hypothesis for the molecular mechanism...

F. R. Camp M. I. Barnhart R. L. Henry R. M. Nalbandian

1972-01-01

169

Advances in radionuclide molecular imaging in myocardial biology.  

PubMed

Molecular imaging is a new and evolving field that employs a targeted approach to noninvasively assess biologic processes in vivo. By assessing key elements in specific cellular processes prior to irreversible end-organ damage, molecular tools will allow for earlier detection and intervention, improving management and outcomes associated with cardiovascular diseases. The goal of those working to expand this field is not just to provide diagnostic and prognostic information, but rather to guide an individual's pharmacological, cell-based, or genetic therapeutic regimen. This article will review molecular imaging tools in the context of our current understanding of biological processes of the myocardium, including angiogenesis, ventricular remodeling, inflammation, and apoptosis. The focus will be on radiotracer-based molecular imaging modalities with an emphasis on clinical application. Though this field is still in its infancy and may not be fully ready for widespread use, molecular imaging of myocardial biology has begun to show promise of clinical utility in acute and chronic ischemia, acute myocardial infarction, congestive heart failure, as well as in more global inflammatory and immune-mediated responses in the heart-like myocarditis and allogeneic cardiac transplant rejection. With continued research and development, molecular imaging promises to be an important tool for the optimization of cardiovascular care. PMID:20012514

Morrison, Alan R; Sinusas, Albert J

170

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

171

Tetric: advanced techniques for a universal direct resin system.  

PubMed

No other restorative methodology has been as intensively and critically investigated as that of tooth-colored restorative options. As the biologic and physiochemical shortcomings of earlier adhesive and restorative resins systems have been identified and corrected, newer materials have been formulated, and new techniques utilized. The use of dental dam, attainment of proximal contacts, and the importance of the first layer of composite resin are often overlooked. This article presents various solutions in the quest for adhesive and aesthetic excellence in anterior and posterior applications using Tetric* (Ivoclar Vivadent, Amherst, NY), a microhybrid that meets the optimal criteria for direct composite resin restorations. PMID:9227158

Liebenberg, W H

1996-01-01

172

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.

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

2013-01-01

173

Advances in dental veneers: materials, applications, and techniques  

PubMed Central

Laminate veneers are a conservative treatment of unaesthetic anterior teeth. The continued development of dental ceramics offers clinicians many options for creating highly aesthetic and functional porcelain veneers. This evolution of materials, ceramics, and adhesive systems permits improvement of the aesthetic of the smile and the self-esteem of the patient. Clinicians should understand the latest ceramic materials in order to be able to recommend them and their applications and techniques, and to ensure the success of the clinical case. The current literature was reviewed to search for the most important parameters determining the long-term success, correct application, and clinical limitations of porcelain veneers.

Pini, Nubia Pavesi; Aguiar, Flavio Henrique Baggio; Lima, Debora Alves Nunes Leite; Lovadino, Jose Roberto; Terada, Raquel Sano Suga; Pascotto, Renata Correa

2012-01-01

174

XII Advanced Computing and Analysis Techniques in Physics Research  

NASA Astrophysics Data System (ADS)

November 2008 will be a few months after the official start of LHC when the highest quantum energy ever produced by mankind will be observed by the most complex piece of scientific equipment ever built. LHC will open a new era in physics research and push further the frontier of Knowledge This achievement has been made possible by new technological developments in many fields, but computing is certainly the technology that has made possible this whole enterprise. Accelerator and detector design, construction management, data acquisition, detectors monitoring, data analysis, event simulation and theoretical interpretation are all computing based HEP activities but also occurring many other research fields. Computing is everywhere and forms the common link between all involved scientists and engineers. The ACAT workshop series, created back in 1990 as AIHENP (Artificial Intelligence in High Energy and Nuclear Research) has been covering the tremendous evolution of computing in its most advanced topics, trying to setup bridges between computer science, experimental and theoretical physics. Conference web-site: http://acat2008.cern.ch/ Programme and presentations: http://indico.cern.ch/conferenceDisplay.py?confId=34666

Speer, Thomas; Carminati, Federico; Werlen, Monique

175

Photoionization of excited molecular states using multiphoton excitation techniques  

SciTech Connect

Photoelectron spectra are reported for three photon resonant, four photon ionization of H/sub 2/ via the B /sup 1/..sigma../sub u//sup +/, v = 7 (J = 2,4) and C /sup 1/..pi../sub u'/, v = 0-4 (J = 1) levels and of N/sub 2/ via the o/sub 3//sup 1/..pi../sub u'/, v = 1,2, b /sup 1/..pi../sub u'/, v = 3-5, and c /sup 1/..pi../sub u'/, v = 0 levels. The results reflect both the spectroscopy and the dynamics of photoionization of excited molecular states and are discussed in terms of the selection rules for photoionization and the relative probabilities of photoionization from Rydberg and valence states. In some cases, in accordance with the Franck-Condon principle, the results demonstrate that resonant multiphoton ionization through Rydberg states may be a powerful technique for the production of electronic, vibrational, and rotational state selected ions. However, in other cases, systematic departures from Franck-Condon factors are observed, which reflect the more subtle dynamics of excited state photoionization. 23 references, 6 figures, 2 tables.

Dehmer, P.M.; Pratt, S.T.; Dehmer, J.L.

1984-01-01

176

[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

177

Laser capture microdissection and advanced molecular analysis of human breast cancer.  

PubMed

Advances in comprehensive genomic and proteomic technologies are providing researchers with an unprecedented opportunity for high-throughput molecular analysis of human breast cancer. Adaptation of these technologies to laser capture microdissection (LCM) is poised to exert dramatic change on the pace of breast cancer research. Although technical limitations have impeded the coupling of these high-throughput technologies to LCM, recent advances have allowed for the successful application of this cellular-based approach to breast cancer, and the results of such studies have provided researchers with unique insight into the disease. This approach holds great potential for rapid advancement in our understanding of breast cancer, and it is hoped that such advancements will lead to novel predictive and therapeutic strategies for women with the disease. This review outlines the current status of the adaptation of advanced molecular technologies to LCM and highlights recent studies in which this approach has been applied to human breast cancer. PMID:14973377

Fuller, Andrew P; Palmer-Toy, Darryl; Erlander, Mark G; Sgroi, Dennis C

2003-07-01

178

Advances in Molecular and Cellular Therapies for Hearing Loss  

Microsoft Academic Search

Development of effective therapeutics for hearing loss has proven to be a slow and difficult process, evidenced by the lack of restorative medicines and technologies currently available to the otolaryngologist. In large part this is attributable to the limited regenerative potential in cochlear cells and the secondary degeneration of the cochlear architecture that commonly follows sensorineural hearing impairment. Therapeutic advances

Michael S Hildebrand; Stephen S Newton; Samuel P Gubbels; Abraham M Sheffield; Amit Kochhar; Michelle G de Silva; Hans-Henrik M Dahl; Scott D Rose; Mark A Behlke; Richard JH Smith

2008-01-01

179

Advanced techniques for multiparton loop calculations: A minireview  

SciTech Connect

Much of the experimental effort in high-energy physics today is directed at searching for new physics beyond the standard model. Successful searches will require a detailed understanding of known physics. At high-energy colliders, particularly hadron-hadron colliders, this requirement implies above all the need for a detailed understanding of perturbative QCD. A detailed theoretical picture of dijet production, for example, is necessary if they are to use it in constraining the gluon distribution. The search for new physics in the single-jet inclusive distribution likewise requires detailed theoretical calculations (in addition to better measurements of the parton distributions than have been available heretofore). Here, the authors present an overview of techniques developed in recent years for the efficient calculation of one-loop multiparton amplitudes, in particular those relying on unitarity and collinear factorization.

Bern, Z. [Univ. of California, Los Angeles, CA (US). Dept. of Physics; Dixon, L. [Stanford Univ., CA (US). Stanford Linear Accelerator Center; Dunbar, D.C. [Univ. Coll. of Swansea (United Kingdom); Kosower, D.A. [CEA-Saclay, Gif-sur-Yvette (France). Service de Physique Theorique

1997-07-01

180

Application of Advanced Rendering and Animation Techniques for 3D Games to Softbody Modeling and Animation  

Microsoft Academic Search

This work focuses on the analysis and review of most prominent advanced rendering and animation techniques in the computer graphics used for 3D games, some of which we then juxtapose with our physically based softbody simulation framework we designed and implemented earlier. We then discuss such implementation results and the future directions. The techniques we touch upon are various algorithms

Miao Song; Peter Grogono

2009-01-01

181

Biotechnology Apprenticeship for Secondary-Level Students: Teaching Advanced Cell Culture Techniques for Research  

ERIC Educational Resources Information Center

|The purpose of this article is to discuss "small-group apprenticeships (SGAs)" as a method to instruct cell culture techniques to high school participants. The study aimed to teach cell culture practices and to introduce advanced imaging techniques to solve various biomedical engineering problems. Participants designed and completed experiments…

Lewis, Jennifer R.; Kotur, Mark S.; Butt, Omar; Kulcarni, Sumant; Riley, Alyssa A.; Ferrell, Nick; Sullivan, Kathryn D.; Ferrari, Mauro

2002-01-01

182

Biotechnology Apprenticeship for Secondary-Level Students: Teaching Advanced Cell Culture Techniques for Research.  

ERIC Educational Resources Information Center

|Discusses small-group apprenticeships (SGAs) as a method for introducing cell culture techniques to high school participants. Teaches cell culture practices and introduces advance imaging techniques to solve various biomedical engineering problems. Clarifies and illuminates the value of small-group laboratory apprenticeships. (Author/KHR)|

Lewis, Jennifer R.; Kotur, Mark S.; Butt, Omar; Kulcarni, Sumant; Riley, Alyssa A.; Ferrell, Nick; Sullivan, Kathryn D.; Ferrari, Mauro

2002-01-01

183

Advanced Techniques for Reservoir Simulation and Modeling of Non-Conventional Wells  

SciTech Connect

This project targets the development of (1) advanced reservoir simulation techniques for modeling non-conventional wells; (2) improved techniques for computing well productivity (for use in reservoir engineering calculations) and well index (for use in simulation models), including the effects of wellbore flow; and (3) accurate approaches to account for heterogeneity in the near-well region.

Durlofsky, Louis J.

2000-08-28

184

Strategies for improved accuracy and efficiency with advanced intensity modulated radiation therapy techniques  

Microsoft Academic Search

The development of advanced intensity modulated radiation therapy (IMRT) techniques has led to significant improvements in our ability to treat complicated target volumes with minimal collateral damage to the surrounding healthy tissue. These techniques however, come at the cost of increased complexity; which translates into increased sensitivity of the optimized treatment plans to inaccuracies in the planning and delivery processes,

David C. Westerly

2009-01-01

185

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

NASA Astrophysics Data System (ADS)

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 13C-enrichment techniques we have developed to distinguish between different N2O-producing processes in situ in soils, presenting selected results, and will critically assess their potential, alone and in combination with molecular techniques, to help address key research questions for soil biogeochemistry and microbial ecology. We have developed 15N- 18O-enrichment techniques to distinguish between, and to quantify, N2O production during ammonia oxidation, nitrifier denitrification and denitrification. This provides a great advantage over natural abundance approaches as it enables quantification of N2O from each microbial source, which can be coupled with quantification of N2 production, and used to examine interactions between different processes and cycles. These approaches have also provided new insights into the N cycle and how it interacts with the C cycle. For example, we now know that ammonia oxidising bacteria significantly contribute to N2O emissions from soils, both via the traditionally accepted ammonia oxidation pathway, and also via denitrification (nitrifier denitrification) which can proceed even under aerobic conditions. We are also linking emissions from each source to diversity and activity of relevant microbial functional groups, for example through the development and application of a specific nirK primer for the nitrite reductase in ammonia oxidising bacteria. Recently, isotopomers have been proposed as an alternative for source partitioning N2O at natural abundance levels, and offers the potential to investigate N2O production from nitrate ammonification, and overcomes the need to apply 18O-H2O to determine nitrifier denitrification. However, this only provides an estimated, not a quantified, contribution, and further developments are required for quantification using isotope enrichment. Despite some limitations, such techniques become even more powerful when linked with other recent developments, such as nanoSIMS, gene expression and 13C-stable isotope probing of microbial RNA, and when linked to other disciplines. These may help address remaining questions such as: which microbes are producing N2O in soil, what is the influence of plants and mycorrhizal fungi on rhizosphere processes, and where is denitrification occurring in soil?

Baggs, E.; Mair, L.; Mahmood, S.

2007-12-01

186

Recent advances in yeast molecular biology: recombinant DNA. [Lead abstract  

SciTech Connect

Separate abstracts were prepared for the 25 papers presented at a workshop focusing on chromosomal structure, gene regulation, recombination, DNA repair, and cell type control, that have been obtained by experimental approaches incorporating the new technologies of yeast DNA transformation, molecular cloning, and DNA sequence analysis. (KRM)

Not Available

1982-09-01

187

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

188

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

189

Recent Advances in molecular simulations of ion solvation at liquid interfaces  

SciTech Connect

In this paper, I present a review of the application of molecular dynamics simulation methods, including which polarizable potential models were used to describe interactions among species, to a variety of chemical and physical processes in solutions and at interfaces. The main emphasis of the review is on recent advances in the understanding of ion solvation, molecular association, and molecular solvation at liquid interfaces. The molecules discussed range from monovalent ions to molecular ions such as hydronium and nitrate ions. The computed properties include potentials of mean force, surface potentials, surface tensions, and density profiles. Comparisons with other simulation studies and experimental results were made and discussed in the review.

Chang, Tsun-Mei; Dang, Liem X.

2006-01-01

190

[Our experience with the treatment of high perianal fistulas with the mucosal flap advancement technique].  

PubMed

The authors present their experience with the treatment of high transphincteric anal fistulas with the mucosal flap advancement technique. This technique, though by no means easy to perform, allows fistulas to be treated in a single surgical session in comparison to the technique in which setone is used or to the less well known transposition techniques, given the same long-term results in terms of continence and recurrence rate. After a brief overview of the problem, from the points of view of both aetiopathogenesis and classification, the principal surgical treatment techniques are described, presenting the results and complications observed in the authors' own case series. PMID:15038659

Marino, Giuseppe; Greco, Ettore; Gasparrini, Marcello; Romanzi, Aldo; Ottaviani, Maurizio; Nasi, Stefano; Pasquini, Giorgio

191

Advances in molecular detection of Aspergillus : an update  

Microsoft Academic Search

Filamentous cosmopolitan fungi of the genus Aspergillus can be harmful in two ways, directly they can be opportunistic pathogens causing aspergillosis and indirectly due to aflatoxin\\u000a production on food products which can lead to aflatoxicosis. Therefore, a number of methods have been proposed so far for\\u000a detection of the fungi with lowest possible concentration at the earliest. Molecular methods such

M. Z. Abdin; Malik M. Ahmad; Saleem Javed

2010-01-01

192

Recent advances in molecular genetics of forest trees  

Microsoft Academic Search

The use of molecular markers has greatly enhanced our understanding of the genome structure of forest trees. Conifers, in\\u000a particular, have a relatively large genome, containing a very high proportion of repeated DNA, consisting of tandemly repetitive\\u000a and dispersed repetitive DNA sequences. The nature of highly conserved tandemly repetitive rRNA genes has been investigated\\u000a in a number of tree species,

M. R. Ahuja

2001-01-01

193

Advancing Characterization of Materials with Atomic Force Microscopy-Based Electric Techniques  

Microsoft Academic Search

\\u000a Multifrequency measurements in atomic force microscopy (AFM) are one of the main techniques advancing this method. Detection\\u000a of the AFM probe response at different frequencies enables simultaneous and independent studies of individual constituents\\u000a of overall tip–sample force and, therefore, begins to empower the advanced compositional mapping and quantitative examination\\u000a of local mechanical, electromagnetic, and other properties of materials. This chapter

Sergei Magonov; John Alexander; Shijie Wu

194

Hydrogeophysical Techniques for Site Characterization and Monitoring: Recent Advances in Ground-penetrating Radar  

Microsoft Academic Search

\\u000a We introduce ground penetrating radar (GPR) basic principles and applications in environmental engineering, with emphasis\\u000a on quantitative methods for soil water content estimation. The main limitations of these techniques are discussed. Then, we\\u000a summarize our recent advances on the development and use of advanced off-ground GPR for shallow subsurface characterization.\\u000a The proposed method is based on full-waveform forward and inverse

Sébastien Lambot; Evert Slob; Marnik Vanclooster; Johan A. Huisman; Harry Vereecken

195

Recent advances in high-speed serial I\\/O trends, standards and techniques  

Microsoft Academic Search

The goal of this paper is to provide the reader with an overview of the recent advances (in the past year) made in the industry with respect to high-speed data transport. The latest developments in the industry's main high-speed I\\/O protocols and the attempted standardization of the high-speed physical interface are presented. In reviewing these advanced techniques, examples will use

Peter Noel; Farhad Zarkeshvari; Tad Kwasniewski

2005-01-01

196

Advances in high-resolution imaging - techniques for three-dimensional imaging of cellular structures  

PubMed Central

A fundamental goal in biology is to determine how cellular organization is coupled to function. To achieve this goal, a better understanding of organelle composition and structure is needed. Although visualization of cellular organelles using fluorescence or electron microscopy (EM) has become a common tool for the cell biologist, recent advances are providing a clearer picture of the cell than ever before. In particular, advanced light-microscopy techniques are achieving resolutions below the diffraction limit and EM tomography provides high-resolution three-dimensional (3D) images of cellular structures. The ability to perform both fluorescence and electron microscopy on the same sample (correlative light and electron microscopy, CLEM) makes it possible to identify where a fluorescently labeled protein is located with respect to organelle structures visualized by EM. Here, we review the current state of the art in 3D biological imaging techniques with a focus on recent advances in electron microscopy and fluorescence super-resolution techniques.

Lidke, Diane S.; Lidke, Keith A.

2012-01-01

197

Advances in high-resolution imaging--techniques for three-dimensional imaging of cellular structures.  

PubMed

A fundamental goal in biology is to determine how cellular organization is coupled to function. To achieve this goal, a better understanding of organelle composition and structure is needed. Although visualization of cellular organelles using fluorescence or electron microscopy (EM) has become a common tool for the cell biologist, recent advances are providing a clearer picture of the cell than ever before. In particular, advanced light-microscopy techniques are achieving resolutions below the diffraction limit and EM tomography provides high-resolution three-dimensional (3D) images of cellular structures. The ability to perform both fluorescence and electron microscopy on the same sample (correlative light and electron microscopy, CLEM) makes it possible to identify where a fluorescently labeled protein is located with respect to organelle structures visualized by EM. Here, we review the current state of the art in 3D biological imaging techniques with a focus on recent advances in electron microscopy and fluorescence super-resolution techniques. PMID:22685332

Lidke, Diane S; Lidke, Keith A

2012-06-08

198

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

Microsoft Academic Search

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

C. P. Gendrich; M. M. Koochesfahani

1996-01-01

199

Traditional and Molecular Techniques for the Study of Emerging Bacterial Diseases: One Laboratory's Perspective  

Microsoft Academic Search

Identification of emerging bacterial pathogens generally results from a chain of events involving micros- copy, serology, molecular tools, and culture. Because of the spectacular molecular techniques developed in the last decades, some authors think that these techniques will shortly supplant culture. The key steps that led to the discovery of emerging bacteria have been reviewed to determine the real contribution

Pierre Houpikian; Didier Raoult

200

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.

Molfese, David L.

2011-01-01

201

Cysticercosis/taeniasis: recent advances in serological and molecular diagnoses.  

PubMed

Serodiagnosis by immunoblot, using recombinant chimeric T. solium antigen and native glycoprotein antigens, has been applied for neurocysticercosis cases. Specific antibodies against both antigens were detected in serum samples from NCC patients involving multiple cysts in the brain, whereas it was not always easy to detect specific antibodies in NCC cases with a solitary cyst or calcified lesion(s). On the other hand, the diagnosis for human taeniasis or worm carriers has been routinely performed by stool examination. In this study, multiplex PCR has been established to differentiate taeniasis using Taenia mitochondrial DNA in fecal samples from worm carriers. Furthermore, the molecular identification of human taeniid cestodes by base excision sequence scanning thymine-base analysis has also been introduced. This method provides four thymine-base peak profiles unique for Asian and American/African genotypes of T. solium, T. saginata and T. asiatica. By comparing thymine base peak profiles, it is possible to differentiate human taeniid cestodes without DNA sequencing. The approaches are powerful tools for the routine diagnosis of taeniasis and the molecular identification of taeniid cestodes. PMID:19230578

Yamasaki, H; Sato, M O; Sako, Y; Nakao, M; Nakaya, K; Mamuti, W; Craig, P S; Margono, S S; Ito, A

2003-01-01

202

Next Generation Risk Assessment: Incorporation of Recent Advances in Molecular, Computational, and Systems Biology (External Review Draft)  

EPA Science Inventory

EPA is releasing a draft report "Next Generation Risk Assessment: Incorporation of Recent Advances in Molecular, Computational, and Systems Biology" that explores how new molecular, computational and systems biology data and approaches (together called "NexGen") could better info...

203

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

204

A comparative assessment of molecular biological and direct microscopic techniques for assessing aquatic systems  

Microsoft Academic Search

Molecular techniques have clear value for community characterization; however, almost all previous datasets are based upon\\u000a non-molecular measurements and it is hard to compare “old” data with “new” data because few correlations have been made. Therefore,\\u000a the purpose of this evaluation was to simultaneously use molecular and non-molecular methods within the same sampling program\\u000a to determine how data compare. Three

C. W. Knapp; D. L. Findlay; K. A. Kidd; D. W. Graham

2008-01-01

205

High rate concentration measurement of molecular gas mixtures using a spatial detection technique  

NASA Astrophysics Data System (ADS)

Concentration measurement in molecular gas mixtures using a snapshot spatial imaging technique is reported. The approach consists of measuring the birefringence of the molecular sample when field-free alignment takes place, each molecular component producing a signal with an amplitude depending on the molecular density. The concentration measurement is obtained on a single-shot basis by probing the time-varying birefringence through femtosecond time-resolved optical polarigraphy (FTOP). The relevance of the method is assessed in air.

Loriot, V.; Hertz, E.; Lavorel, B.; Faucher, O.

2010-05-01

206

ADVANCED DIAGNOSTIC TECHNIQUES FOR THREE-PHASE SLURRY BUBBLE COLUMN REACTORS(SBCR)  

SciTech Connect

The objectives set for this cooperative project between Washington University (WU), Ohio State University (OSU), and Air Products and Chemicals, Inc. (APCI) to advance the understanding of the Fischer-Tropsch (FT) slurry bubble column reactor hydrodynamics for proper design and scale-up via advanced diagnostic techniques have been accomplished successfully despite the unexpected challenging technical difficulties in implementing the advanced techniques in high pressure stainless steel slurry bubble column. In this work, a detailed review of the aspects of high pressure phenomena of bubbles in liquids and liquid-solids suspension was performed. All the challenging technical problems mentioned above were resolved and the advanced measurement techniques were successfully used in this project. The effects of reactor pressure, superficial gas velocity, solids loading, and liquid physical properties on the overall gas holdup, holdups distribution, recirculation velocity, turbulent parameters, bubble dynamics (size and rise velocity) were investigated via advanced measurement techniques that includes optical probe, Laser Doppler Anemometry (LDA), Computed Tomography (CT), Computer Automated Radioactive Particle Tracking (CARPT). The findings are discussed and analyzed in this report. In attempt to advance the design and scale-up of bubble columns, new correlations have been developed based on a large bank of data collected at a wide range of operating and design conditions. These correlations are for prediction of radial gas holdup profile, axial liquid velocity profile, overall gas holdup based on Neural Network and gas-liquid mass transfer coefficient. Despite the noticeable advances made on FT SBCR as a part of this project, there are still many parameters and challenging issues that need to be further and properly investigated and understood before this technology will be readily used for alternative fuel development technology.

M.H. Al-Dahhan; L.S. Fan; M.P. Dudukovic

2003-08-01

207

Recent advances in the molecular diagnosis of paediatric soft tissue sarcomas  

Microsoft Academic Search

Sarcomas comprise a significant portion of solid tumours diagnosed in children. As they commonly are composed of primitive round or spindled cells, morphologic diagnosis can be difficult, and ancillary studies are often necessary. In recent years, progress has been made in understanding the cytogenetic and molecular changes underlying many of these tumours, and molecular techniques have emerged from strictly being

Bruce R. Pawel

2011-01-01

208

Advances in molecular analysis of fragile X syndrome.  

PubMed

Fragile X syndrome is a common cause of mental retardation that is inherited as an X-linked dominant disorder with reduced penetrance. Fragile X syndrome has been shown to be caused by an unstable CGG repeat within the fragile X mental retardation-1 (FMR1) gene. The repeat is normally polymorphic with six to 52 repeats, while affected males and females exhibit a massive expansion resulting in 230 to more than 1000 repeats. Such expansions, called "full mutations," are associated with abnormal methylation of the FMR1 gene leading to transcriptional suppression. The resulting absence of the encoded protein, FMRP, a cytosolic RNA-binding protein, is believed to result in the phenotype. Nonpenetrant male carriers and many female carriers exhibit premutation alleles of intermediate length (50 to 230 repeats), which are normally expressed. Male carriers transmit only unstable premutations while female premutation carriers can have carrier offspring with premutations or affected children with full mutations. The risk of having an affected child is directly related to the number of maternal repeats, with sequentially increasing probabilities of these alleles converting to full mutations as they are transmitted to subsequent generations. Advances have led to highly accurate laboratory diagnoses of both carrier and affected individuals as well as markedly improved prenatal diagnosis. In addition, a previously unrecognized class of mutation, later found responsible for several other important genetic diseases, has emerged. PMID:8301769

Warren, S T; Nelson, D L

1994-02-16

209

Progress of Molecular Targeted Therapies for Advanced Renal Cell Carcinoma  

PubMed Central

Vascular endothelial growth factor (VEGF) plays a crucial role in tumor angiogenesis. VEGF expression in metastatic renal cell carcinoma (mRCC) is mostly regulated by hypoxia, predominantly via the hypoxia-induced factor (HIF)/Von Hippel-Lindau (VHL) pathway. Advances in our knowledge of VEGF role in tumor angiogenesis, growth, and progression have permitted development of new approaches for the treatment of mRCC, including several agents targeting VEGF and VEGF receptors: tyrosine kinase pathway, serine/threonine kinases, ?5?1-integrin, deacetylase, CD70, mammalian target of rapamycin (mTOR), AKT, and phosphatidylinositol 3?-kinase (PI3K). Starting from sorafenib and sunitinib, several targeted therapies have been approved for mRCC treatment, with a long list of agents in course of evaluation, such as tivozanib, cediranib, and VEGF-Trap. Here we illustrate the main steps of tumor angiogenesis process, defining the pertinent therapeutic targets and the efficacy and toxicity profiles of these new promising agents.

Santoni, Matteo; Amantini, Consuelo; Burattini, Luciano; Berardi, Rossana; Santoni, Giorgio; Cascinu, Stefano; Muzzonigro, Giovanni

2013-01-01

210

Advances in developing molecular-diagnostic tools for strongyloid nematodes of equids: fundamental and applied implications.  

PubMed

Infections of equids with parasitic nematodes of the order Strongylida (subfamilies Strongylinae and Cyathostominae) are of major veterinary importance. In last decades, the widespread use of drugs against these parasites has led to problems of resistance within the Cyathostominae, and to an increase in their prevalence and intensity of infection. Novel control strategies, based on improved knowledge of parasite biology and epidemiology, have thus become important. However, there are substantial limitations in the understanding of fundamental biological and systematic aspects of these parasites, which have been due largely to limitations in their specific identification and diagnosis using traditional, morphological approaches. Recently, there has been progress in the development of DNA-based approaches for the specific identification of strongyloids of equids for systematic studies and disease diagnosis. The present article briefly reviews information on the classification, biology, pathogenesis, epidemiology of equine strongyloids and the diagnosis of infections, highlights knowledge gaps in these areas, describes recent advances in the use of molecular techniques for the genetic characterisation, specific identification and differentiation of strongyloids of equids as a basis for fundamental investigations of the systematics, population biology and ecology. PMID:15036364

Gasser, Robin B; Hung, Guo-Chiuan; Chilton, Neil B; Beveridge, Ian

2004-02-01

211

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.

Koedrith, Preeyaporn; Seo, Young Rok

2011-01-01

212

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

213

Molecular advances in understanding social insect population structure.  

PubMed

Social insects present many phenomena seen in all organisms but in more extreme forms and with larger sample sizes than those observable in most natural populations of vertebrates. Microsatellites are proving very much more informative than allozymes for the analysis of population biological problems, and prolifically polymorphic markers are fairly readily developed. In addition, the male-haploid genetic system of many social insects facilitates genetic analysis. The ability to amplify DNA from sperm stored in a female's sperm storage device enables the determination of mating types long after the death of the short-lived males, in addition to information on the degree of mixing of sperm from different males. Mitochondrial (mt) DNA sequences are also proving important, not only in phylogenetic studies but also in molecular population genetics, as a tracer of female movements. Mitochondrial markers have definitively shown the movement of females between colonies, challenging models giving exclusive primacy to kin selection as the explanation for multiqueen colonies, in Australian meat ants, Iridomyrmex purpureus, and the aridzone queenless ant Rhytidoponera sp. 12. Microsatellite and mtDNA variation are being studied in Camponotus consobrinus sugar ants, showing an unexpected diversity of complexity in colony structure, and microsatellites have shown that transfer of ants between nests of the weaver ant Polyrhachis doddi must be slight, despite an apparent lack of hostility. PMID:9378143

Crozier, R H; Oldroyd, B P; Tay, W T; Kaufmann, B E; Johnson, R N; Carew, M E; Jennings, K M

1997-08-01

214

Bacteria and Archaea: Molecular techniques reveal astonishing diversity  

Microsoft Academic Search

The last decade has produced a significant advance in our appreciation of the diversity of prokaryotic organisms (commonly given the generic term “bacteria”). The need for this improvement was clear as the current list of approximately 5,000 accredited species has long been known to be a major underestimate of living prokaryotic species. The primary reasons for this poor census were

James O. McInerney; Marice Mullarkey; Martina E. Wernecke; Richard Powell

2002-01-01

215

Advanced optical tweezers for the study of cellular and molecular biomechanics  

Microsoft Academic Search

Optical tweezers are an important tool for studying cellular and molecular biomechanics. We present a robust optical tweezers device with advanced features including: multiple optical traps, acousto-optic trap steering, and back focal plane interferometry position detection. We integrate these features into an upright microscope, with no compromise to its capabilities (differential interference contrast microscopy (DIC), fluorescence microscopy, etc.). Acousto-optic deflectors

Gary J. Brouhard; Henry T. Schek; Alan J. Hunt

2003-01-01

216

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

Microsoft Academic Search

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

Peter de Knijff; Manfred Kayser

2011-01-01

217

The causes of obesity: advances in molecular biology but stagnation on the genetic front  

Microsoft Academic Search

Exciting advances have been made in the field of obesity over the last few years particularly with respect to the molecular determinants of energy balance. Although much remains to be uncovered, there is growing optimism that the causes of the susceptibility to be in positive energy balance will be identified. It is important, however, to appreciate the fact that the

C. Bouchard

1996-01-01

218

Molecular alignment and orientation with a hybrid Raman scattering technique  

NASA Astrophysics Data System (ADS)

We demonstrate a scheme for the preparation of molecular alignment and angular momentum orientation using a hybrid combination of two limits of Raman scattering. First a weak, impulsive pump pulse initializes the system via the nonresonant dynamic Stark effect. Then, having overcome the influence of the vacuum fluctuations, an amplification pulse selectively enhances the initial coherences by transient stimulated Raman scattering, generating alignment and angular momentum orientation of molecular hydrogen. The amplitude and phase of the resulting coherent dynamics are experimentally probed, indicating an amplification factor of 4.5. An analytic theory is developed to model the dynamics.

Bustard, Philip J.; Lausten, R.; Sussman, Benjamin J.

2012-11-01

219

Mass spectrometric imaging (MSI) of metals using advanced BrainMet techniques for biomedical research  

Microsoft Academic Search

Mass spectrometric imaging (MSI) is a young innovative analytical technique and combines different fields of advanced mass spectrometry and biomedical research with the aim to provide maps of elements and molecules, complexes or fragments. Especially essential metals such as zinc, copper, iron and manganese play a functional role in signaling, metabolism and homeostasis of the cell. Due to the high

Johanna Sabine Becker; Andreas Matusch; Julia Susanne Becker; Bei Wu; Christoph Palm; Albert Johann Becker; Dagmar Salber

2011-01-01

220

Highlights of nuclear medicine. [Recent advances in techniques, raiopharmaceuticals, and data analysis  

Microsoft Academic Search

This summary discusses recent advances in nuclear medicine techniques for the diagnosis of cardiovascular diseases, renal imaging, pulmonary studies, gastrointestinal studies, hematological studies, imaging bone joints, immunological approaches to the in vivo radioisotopic detection of cancer, brain imaging, imaging endocrine glands with emphasis on adrenal and thyroid function studies, pediatric nuclear medicine, the development of new radiopharmaceuticals and imaging instruments,

1977-01-01

221

Removal of selected pharmaceuticals from sewage water by advanced treatment techniques  

Microsoft Academic Search

The presence of pharmaceuticals as trace pollutants in natural surface water bodies, ground water and drinking water has recently led to some concern. Since sewage is the main source of this type of pollution, some attempts have been made to remove pharmaceuticals by advanced physical, chemical and biological techniques which go further than the conventional treatment. A few of these

René Wetzig

222

Application of Software Engineering Techniques to the Advanced Laboratory of the Cooperative Course  

Microsoft Academic Search

Practical Software Engineering courses are generally dealt with software system development. Students apply the waterfall life cycle to realize their project. The environment which supports the course is rigid and it does not allow to explore variability of software processes and techniques. This work presents one solution utilized in Software Engineering Advanced Laboratory of Computing Engineering Course of Escola Politécnica

Jorge L. Risco; Selma S. Shimizu; J. Eduardo Morello; Beatriz T. Borsoi

2007-01-01

223

Recent advances in hantavirus molecular biology and disease.  

PubMed

Hantaviruses are emerging zoonotic pathogens that belong to the Bunyaviridae family. They have been classified as category A pathogens by CDC (centers for disease control and prevention). Hantaviruses pose a serious threat to human health because their infection causes two highly fatal diseases, hemorrhagic fever with renal syndrome (HFRS) and hantavirus cardiopulmonary syndrome (HCPS). These pathogens are transmitted to humans through aerosolized excreta of their infected rodent hosts. Hantaviruses have a tripartite-segmented negative-sense RNA genome. The three genomic RNA segments, S, M, and L, encode a nucleocapsid protein (N), a precursor glycoprotein that is processed into two envelope glycoproteins (Gn and Gc) and the viral RNA-dependent RNA polymerase (RdRp), respectively. N protein is the major structural component of the virus, its main function is to protect and encapsidate the three genomic RNAs forming three viral ribonucleocapsids. Recent studies have proposed that N in conjunction with RdRp plays important roles in the transcription and replication of viral genome. In addition, N preferentially facilitates the translation of viral mRNA in cells. Glycoproteins, Gn and Gc, play major roles in viral attachment and entry to the host cells, virulence, and assembly and packaging of new virions in infected cells. RdRp functions as RNA replicase and transcriptase to replicate and transcribe the viral RNA and is also thought to have endonuclease activity. Currently, no antiviral therapy or vaccine is available for the treatment of hantavirus-associated diseases. Understanding the molecular details of hantavirus life cycle will help in the identification of targets for antiviral therapeutics and in the design of potential antiviral drug for the treatment of HFRS and HCPS. Due to the alarming fatality of hantavirus diseases, development of an effective vaccine against hantaviruses is a necessity. PMID:21459193

Hussein, Islam T M; Haseeb, Abdul; Haque, Absarul; Mir, Mohammad A

2011-01-01

224

Ultrasmall volume molecular isothermal amplification in microfluidic chip with advanced surface processing  

NASA Astrophysics Data System (ADS)

In this paper, we developed a metal micro-fluidic chip with advanced surface processing for ultra-small volume molecular isothermal amplification. This method takes advantages of the nucleic acid amplification with good stability and consistency, high sensitivity about 31 genomic DNA copies and bacteria specific gene identification. Based on the advanced surface processing, the bioreaction assays of nucleic acid amplification was dropped about 392nl in volume. A high numerical aperture confocal optical detection system was advanced to sensitively monitor the DNA amplification with low noise and high power collecting fluorescence near to the optical diffraction limit. A speedy nucleic acid isothermal amplification was performed in the ultra-small volume microfluidic chip, where the time at the inflexions of second derivative to DNA exponential amplified curves was brought forward and the sensitivity was improved about 65 folds to that of in current 25?l Ep-tube amplified reaction, which indicates a promising clinic molecular diagnostics in the droplet amplification.

Huang, Guoliang; Ma, Li; Yang, Xiaoyong; Yang, Xu

2011-01-01

225

The Use of Molecular Techniques at Hazardous Waste Sites  

EPA Science Inventory

It is clear that typical protocols used for soil analysis would certainly fail to adequately interrogate ground-water treatment systems unless they were substantially modified. The modifications found necessary to compensate for the low biomass include molecular tools and techniq...

226

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

227

Conventional and molecular techniques for the early diagnosis of bacteraemia.  

PubMed

Bloodstream infections account for 30-40% of all cases of severe sepsis and septic shock, and are major causes of morbidity and mortality. Diagnosis of bloodstream infections must be performed promptly so that adequate antimicrobial therapy can be started and patient outcome improved. An ideal diagnostic technology would identify the infecting organism(s) and their determinants of antibiotic resistance, in a timely manner, so that appropriate pathogen-driven therapy could begin promptly. Unfortunately, despite the essential information it provides, blood culture, the gold standard, largely fails in this purpose because time is lost waiting for bacterial or fungal growth. Several efforts have been made to optimise the performance of blood culture, such as the development of technologies to obtain rapid detection of microorganism(s) directly in blood samples or in a positive blood culture. The ideal molecular method would analyse a patient's blood sample and provide all the information needed to immediately direct optimal antimicrobial therapy for bacterial or fungal infections. Furthermore, it would provide data to assess the effectiveness of the therapy by measuring the clearance of microbial nucleic acids from the blood over time. None of the currently available molecular methods is sufficiently rapid, accurate or informative to achieve this. This review examines the principal advantages and limitations of some traditional and molecular methods commercially available to help the microbiologist and the clinician in the management of bloodstream infections. PMID:21129933

Paolucci, Michela; Landini, Maria Paola; Sambri, Vittorio

2010-12-03

228

Protocols, practices, and the reproduction of technique in molecular biology.  

PubMed

Protocols are one of the main organizational resources in molecular biology. They are written instructions that specify ingredients, equipment, and sequences of steps for making technical preparations. Some protocols are published in widely used manuals, while others are hand-written variants used by particular laboratories and individual technicians. It is widely understood, both in molecular biology and in social studies of science, that protocols do not describe exactly what practitioners do in the laboratory workplace. In social studies of science, the difference between protocols and the actual practices of doing them often is used to set up ironic contrasts between 'messy' laboratory practices and the appearance of technical order. Alternatively, in ethnomethodological studies of work, the difference is examined as a constitutive feature, both of the lived-work of doing technical projects, and of the administrative work of regulating and evaluating such projects. The present article takes its point of departure from ethnomethodology, and begins with a discussion of local problems with performing molecular biology protocols on specific occasions. The discussion then moves to particular cases in criminal law in which defense attorneys cross-examine forensic technicians and lab administrators. In these interrogations, the distinction between protocols and actual practices animates the dialogue and becomes consequential for judgments in the case at hand. The article concludes with a discussion of administrative science: the work of treating protocols and paper trails as proxies for actual 'scientific' practices. PMID:12171609

Lynch, Michael

2002-06-01

229

Field-Biased Molecular Simulation Technique for Polyelectrolytes  

NASA Astrophysics Data System (ADS)

External fields can be used to impose density profiles in inhomogeneous fluids and interfacial phenomena1. In this study an electric field has been imposed on 1372 hard spheres through 20 negative point charges and 20 positive charges. Also, the effect of partial charges was investigated on a polyelectrolyte with implicit and explicit solvent. Long-range interactions are considered through particle-mesh Ewald summation and its pairwise alternatives. It has been found that it is not necessary to update the Coulombic interactions after each time-step. Energy is conserved even after many numbers of time-steps. Therefore, the computation time for the long-range interaction is less than the discontinuous molecular dynamic (DMD) and/or discontinuous Monte Carlo components. This means that the forced-biased discontinuous molecular simulation method is viable for future studies of confined fluids containing interface and ionic liquids as performed with a field-biased conventional molecular dynamic method by Wardle et al. Finally, the effect of the biased method on dihedral angle is investigated.

Vahid, Amir; Elliott, J. Richard

2010-03-01

230

Applications of advanced electron microscopy techniques to the studies of radiation effects in ceramic materials  

NASA Astrophysics Data System (ADS)

This paper summarizes some recent results from the application of several advanced transmission electron microscopy (TEM) techniques to the studies of radiation effects in insulators with the main focus on radiation-induced amorphization. These techniques include in situ TEM during ion-beam irradiation at cryogenic and elevated temperatures, cross-sectional TEM, high-resolution TEM, and image simulation on partially damaged materials, as well as digital TEM with image processing and analysis. The combination of these techniques may often provide very detailed information about the microstructure evolution during energetic particle irradiation, especially at the early stages, which is unobtainable with any other analytical methods. These techniques have been successfully applied to the analysis of a large group of ion-beam-irradiated ceramics, including quartz, silicon carbides, uranium oxide, apatite, spinel and other complex mineral phases. The advantages and limitations of each technique, as well as some important technical details for the analysis of radiation damage in ceramics are presented.

Wang, L. M.

1998-05-01

231

Nonequilibrium molecular dynamics via a nondiverging subtraction technique  

NASA Astrophysics Data System (ADS)

The subtraction technique is a powerful tool for studying nonequilibrium phenomena in many-body systems at short times. Its major limitation lies in the long-time noise due to the Lyapunov divergence of initially close trajectories in phase space. We present a method to compute transport coefficients even when long-time tails are present, with a subtraction technique modified by adding a kind of frictional force field to monitor the phase-space divergence. The price to be paid is to perform an extrapolation of the results to zero field.

Paolini, G. V.; Ciccotti, G.; van Beijeren, H.

1990-11-01

232

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

233

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

234

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

235

Formation of Ultra-Shallow Junctions by Advanced Plasma Doping Techniques  

SciTech Connect

The fabrication of advanced CMOS devices calls for production worthy doping solutions to address requirements for increasingly shallow and abrupt junctions, while maintaining high dopant activation to meet series resistance requirements. Plasma Doping (PLAD), which has already been adopted in high volume manufacturing in the ultra high dose, low energy regime for advanced DRAM technology nodes, is now being investigated for source drain extension (SDE) implants, where precise and repeatable dopant placement is critical for maintaining control over device parameters. In this article, we investigate the process performance of SDE implants carried out in a VIISta registered PLAD system using p- type dopant precursors. Key metrics, such as junction depth, profile abruptness and sheet resistance are reported for as-implanted junctions, as well as samples processed with low thermal budget anneal techniques. Device performance data demonstrating the feasibility of the approach are presented. The advanced control features in the PLAD system are critical in enabling the process performance required for SDE implants.

Papasouliotis, G. D.; Godet, L.; Singh, V.; Miura, R.; Ito, H. [Varian Semiconductor Equipment Associates, 35 Dory Road, Gloucester, MA, 01930 (United States)

2011-01-07

236

Detection of Molecular signatures of life using immunoassay techniques  

NASA Astrophysics Data System (ADS)

The Miniaturized Array for Solar System Exploration (MASSE) will use a microarray of antibody assays to search for biomarkers in extraterrestrial environments. We have now used enzyme linked immunosorbent assay (ELISA) to demonstrate the feasibility of immuno-detection of biomarkers in terrestrial soil, JSC-1 Mars regolith simulant, and terrestrial polar permafrost as analogues f ro extraterrestrial materials. We have also demonstrated that the technique works at microgravity and Martian gravity. Studies are now underway to test immunoassay techniques and antibody arrays at varying pressures and temperatures. It is expected that these studies will lead to a flight ready biomarker detection instrument that will be landed and operated on the Martian surface in 2009.

McKay, D.; Steele, A.; Warmflash, D.; Maule, J.; Lynch, K.

237

Single Molecular Membrane Glue Technique for Laser Driven Shock Experiments  

NASA Astrophysics Data System (ADS)

The present report describes the adhesion of metal foils without a conventional glue to provide a precise thickness (˜ 20 ?m) of an adhered step target for ultrahigh pressure, laser shock experiments. The technique involves two processes: single molecule coating on the metal surface and fastening the two surfaces together. For the two 20 ?m aluminum targets of single foil and adhered foils, a negligible difference in laser shock speed was observed in comparison with laser energy and target thickness.

Nagai, Keiji; Norimatsu, Takayoshi; Yamanaka, Tatsuhiko; Nishibe, Tsutomu; Ozaki, Norimasa; Takamatsu, Kikuo; Ono, Takatoshi; Nakano, Motohiro; Tanaka, Kazuo A.

2002-10-01

238

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

239

Acetone preservation: a practical technique for molecular analysis.  

PubMed

In attempts to establish a convenient and reliable method for field collection and archival preservation of insects and their endosymbiotic microorganisms for molecular analysis, acetone, ethanol, and other organic solvents were tested for DNA preservability of the pea aphid Acyrthosiphon pisum and its intracellular symbiotic bacterium Buchnera sp. After 6 months' storage, not only the band of high-molecular-size DNA but also the bands of rRNA were well preserved in acetone, ethanol, 2-propanol, diethyl ether and ethyl acetate. Polymerase chain reaction (PCR) assays confirmed that the DNA of both the insects and their symbionts was well preserved in these solvents. In contrast, methanol and chloroform showed poor DNA preservability. When water-containing series of acetone and ethanol were examined for DNA preservability, acetone was apparently more robust against water contamination than ethanol. Considering that most biological materials contain high amounts of water, acetone may be a more recommendable preservative for DNA analysis than ethanol which has been widely used for this purpose. The DNA of various insects could be preserved in acetone at room temperature in good condition for several years. In addition to the DNA of the host insects, the DNA of their endosymbionts, including Buchnera and other mycetocyte symbionts, Wolbachia, and gut bacteria, was amplified by PCR after several years of acetone storage. The RNA and protein of the pea aphid and its endosymbiont were also preserved for several years in acetone. After 2 years' storage in acetone, proteins of A. pisum could be analysed by sodium dodecyl sulphate-polyacrylamide gel electrophoresis (SDS-PAGE) and immunoblotting, and the endosymbiotic bacteria were successfully detected by immunohistochemistry and in situ hybridization on the tissue sections. PMID:10620236

Fukatsu, T

1999-11-01

240

[Principles and advanced techniques for better internetpresentations in obstetrics and gynecology].  

PubMed

Internet presentations are common tools for better medical communication and better scientific work. Meanwhile a great number of gynecological and obstetrical institutions present data via the world wide web within a wide range of quality and performance. Specific HTML editors offer quick and easy presentations, but only advanced internet techniques enable interesting multimedia presentations. N-tier applications are the future standard and we must integrate them in general informatical systems. New Concepts, actual tools and general problems will be discussed and new principles similar to actual E commerce techniques are able to solve our special medical demands. PMID:11562809

Seufert, R; Molitor, N; Pollow, K; Woernle, F; Hawighorst-Knapstein, S

2001-08-01

241

Advanced digital modulation: Communication techniques and monolithic GaAs technology  

NASA Astrophysics Data System (ADS)

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.

1983-07-01

242

Monitoring of the Beauregard landslide (Aosta Valley, Italy) using advanced and conventional techniques  

Microsoft Academic Search

An advanced monitoring technique, based on radar interferometry and implemented by using a ground-based instrumentation (GBInSAR) has been applied for monitoring the Beauregard Deep Seated Gravitational Slope Deformation. This landslide is located in the Aosta Valley (on the Dora di Valgrisenche river), in northwestern Italy, and impinges on a 132m high concrete arch-gravity dam. This is recognized to have relevant

G. Barla; F. Antolini; M. Barla; E. Mensi; G. Piovano

2010-01-01

243

Recent advances in endpoint and in-line monitoring techniques for chemical-mechanical polishing processes  

NASA Astrophysics Data System (ADS)

We present a summary of the recent advances in endpoint and in-line monitoring techniques for chemical-mechanical polishing (CMP) processes. We discuss the technical challenges and review some of the approaches that have been published and/or patented. These methods include optical, thermal (pad temperature), friction (torque motor current), electrochemical, chemical, electrical, and acoustic (vibration). We also present experimental data obtained in our laboratory using selected endpoint methods for metal and oxide CMP.

Stein, David J.; Hetherington, Dale L.

2001-04-01

244

Monitoring complex bacterial communities using culture-independent molecular techniques: application to soil environment  

Microsoft Academic Search

Over the last decade, important advances in molecular biology led to the development of culture-independent approaches to describing bacterial communities. These new strategies, based on the analysis of DNA directly extracted from environmental samples, circumvent the steps of isolation and culturing of bacteria, which are known for their selectivity leading to a non-representative view of the extent of bacterial diversity.

Lionel Ranjard; Franck Poly; Sylvie Nazaret

2000-01-01

245

Inter-kingdom encounters: recent advances in molecular bacterium–fungus interactions  

Microsoft Academic Search

Interactions between bacteria and fungi are well known, but it is often underestimated how intimate and decisive such associations\\u000a can be with respect to behaviour and survival of each participating organism. In this article we review recent advances in\\u000a molecular bacterium–fungus interactions, combining the data of different model systems. Emphasis is given to the positive\\u000a or negative consequences these interactions

Mika T. Tarkka; Alain Sarniguet; Pascale Frey-Klett

2009-01-01

246

Detecting Molecular Properties by Various Laser-Based Techniques  

SciTech Connect

Four different laser-based techniques were applied to study physical and chemical characteristics of biomolecules and dye molecules. These techniques are liole burning spectroscopy, single molecule spectroscopy, time-resolved coherent anti-Stokes Raman spectroscopy and laser-induced fluorescence microscopy. Results from hole burning and single molecule spectroscopy suggested that two antenna states (C708 & C714) of photosystem I from cyanobacterium Synechocystis PCC 6803 are connected by effective energy transfer and the corresponding energy transfer time is {approx}6 ps. In addition, results from hole burning spectroscopy indicated that the chlorophyll dimer of the C714 state has a large distribution of the dimer geometry. Direct observation of vibrational peaks and evolution of coumarin 153 in the electronic excited state was demonstrated by using the fs/ps CARS, a variation of time-resolved coherent anti-Stokes Raman spectroscopy. In three different solvents, methanol, acetonitrile, and butanol, a vibration peak related to the stretch of the carbonyl group exhibits different relaxation dynamics. Laser-induced fluorescence microscopy, along with the biomimetic containers-liposomes, allows the measurement of the enzymatic activity of individual alkaline phosphatase from bovine intestinal mucosa without potential interferences from glass surfaces. The result showed a wide distribution of the enzyme reactivity. Protein structural variation is one of the major reasons that are responsible for this highly heterogeneous behavior.

Tse-Ming Hsin

2007-08-03

247

Monitoring of microbial souring in chemically treated, produced-water biofilm systems using molecular techniques  

Microsoft Academic Search

The identification of bacteria in oil production facilities has previously been based on culture techniques. However, cultivation of bacteria from these often-extreme environments can lead to errors in identifying the microbial community members. In this study, molecular techniques including fluorescence in situ hybridization, PCR, denaturing gradient gel electrophoresis, and sequencing were used to track changes in bacterial biofilm populations treated

B. V. Kjellerup; R. H. Veeh; P. Sumithraratne; T. R. Thomsen; K. Buckingham-Meyer; B. Frølund; P. Sturman

2005-01-01

248

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.

Garcia, Joaquin J.

2010-01-01

249

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

250

Performance Characterization of Molecular Dynamics Techniques for Biomolecular Simulations  

SciTech Connect

Large-scale simulations and computational modeling using molecular dynamics (MD) continues to make significant impacts in the field of biology. It is well known that simulations of biological events at native time and length scales requires computing power several orders of magnitude beyond today's commonly available systems. Supercomputers, such as IBM Blue Gene/L and Cray XT3, will soon make tens to hundreds of teraFLOP/s of computing power available by utilizing thousands of processors. The popular algorithms and MD applications, however, were not initially designed to run on thousands of processors. In this paper, we present detailed investigations of the performance issues, which are crucial for improving the scalability of the MD-related algorithms and applications on massively parallel processing (MPP) architectures. Due to the varying characteristics of biological input problems, we study two prototypical biological complexes that use the MD algorithm: an explicit solvent and an implicit solvent. In particular, we study the AMBER application, which supports a variety of these types of input problems. For the explicit solvent problem, we focused on the particle mesh Ewald (PME) method for calculating the electrostatic energy, and for the implicit solvent model, we targeted the Generalized Born (GB) calculation. We uncovered and subsequently modified a limitation in AMBER that restricted the scaling beyond 128 processors. We collected performance data for experiments on up to 2048 Blue Gene/L and XT3 processors and subsequently identified that the scaling is largely limited by the underlying algorithmic characteristics and also by the implementation of the algorithms. Furthermore, we found that the input problem size of biological system is constrained by memory available per node. In conclusion, our results indicate that MD codes can significantly benefit from the current generation architectures with relatively modest optimization efforts. Nevertheless, the key for enabling scientific breakthroughs lies in exploiting the full potential of these new architectures.

Alam, Sadaf R [ORNL

2006-03-01

251

A perfect time to harness advanced molecular technologies to explore the fundamental biology of Toxocara species.  

PubMed

Toxocarosis is of major canine health and socioeconomic importance worldwide. Although many studies have given insights into toxocarosis, to date, there has been limited exploration of the molecular biology, biochemistry, genetics, epidemiology and ecology of Toxocara species as well as parasite-host interactions using '-omic' technologies. The present article gives a background on Toxocara species and toxocarosis, describes molecular tools for specific identification and genetic analysis, and provides a prospective view of the benefits that advanced molecular technologies will have towards better understanding the parasites and disease. Tackling key biological questions employing a 'systems biology' approach should lead to new and improved strategies for the treatment, diagnosis and control of toxocarosis. PMID:23485434

Gasser, Robin B

2012-12-20

252

Comparison of selected analytical techniques for protein sizing, quantitation and molecular weight determination  

Microsoft Academic Search

Protein analysis techniques are developing fast due to the growing number of proteins obtained by recombinant DNA techniques. In the present paper we compare selected techniques, which are used for protein sizing, quantitation and molecular weight determination: sodium dodecylsulfate-polyacrylamide gel electrophoresis (SDS-PAGE), lab-on-a-chip or microfluidics technology (LoaC), size exclusion chromatography (SEC) and mass spectrometry (MS). We compare advantages and limitations

H. Goetz; M. Kuschel; T. Wulff; C. Sauber; C. Miller; S. Fisher; C. Woodward

2004-01-01

253

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

254

Nanopositioning techniques development for synchrotron radiation instrumentation applications at the Advanced Photon Source  

SciTech Connect

At modern synchrotron radiation sources and beamlines, high-precision positioning techniques present a significant opportunity to support state-of-the-art synchrotron radiation research. Meanwhile, the required instrument positioning performance and capabilities, such as resolution, dynamic range, repeatability, speed, and multiple axes synchronization are exceeding the limit of commercial availability. This paper presents the current nanopositioning techniques developed for the Argonne Center for Nanoscale Materials (CNM)/Advanced Photon Source (APS) hard x-ray nanoprobe and high-resolution x-ray monochromators and analyzers for the APS X-ray Operations and Research (XOR) beamlines. Future nanopositioning techniques to be developed for the APS renewal project will also be discussed.

Shu Deming [Advanced Photon Source, Argonne National Laboratory, Argonne, IL 60439 (United States)

2010-06-23

255

Advances in magnetic resonance neuroimaging techniques in the evaluation of neonatal encephalopathy.  

PubMed

Magnetic resonance (MR) imaging has become an essential tool in the evaluation of neonatal encephalopathy. Magnetic resonance-compatible neonatal incubators allow sick neonates to be transported to the MR scanner, and neonatal head coils can improve signal-to-noise ratio, critical for advanced MR imaging techniques. Refinement of conventional imaging techniques include the use of PROPELLER techniques for motion correction. Magnetic resonance spectroscopic imaging and diffusion tensor imaging provide quantitative assessment of both brain development and brain injury in the newborn with respect to metabolite abnormalities and hypoxic-ischemic injury. Knowledge of normal developmental changes in MR spectroscopy metabolite concentration and diffusion tensor metrics is essential to interpret pathological cases. Perfusion MR and functional MR can provide additional physiological information. Both MR spectroscopy and diffusion tensor imaging can provide additional information in the differential of neonatal encephalopathy, including perinatal white matter injury, hypoxic-ischemic brain injury, metabolic disease, infection, and birth injury. PMID:17607141

Panigrahy, Ashok; Blüml, Stefan

2007-02-01

256

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

257

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.

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

2009-01-01

258

Advanced Self-adaptation Learning and Inference Techniques for Fuzzy Petri Net Expert System Units  

NASA Astrophysics Data System (ADS)

In a complicated expert reasoning system, it is inefficient for commonly fuzzy production rules to depict the vague and modified knowledge. Fuzzy Petri nets are more accurate for dynamic knowledge proposition in describing expert knowledge. However, the bad learning ability of fuzzy Petri net constrains its application in dynamic knowledge expert system. In this paper, an advanced self-adaptation learning way based on error back-propagation is proposed to train parameters of fuzzy production rules in fuzzy Petri net. In order to enhance reasoning and learning efficiency, fuzzy Petri net is transformed into hierarchy model and continuous functions are built to approximate transition firing and fuzzy reasoning. Simulation results show that the designed advanced learning way can make rule parameters arrive at optimization rapidly. These techniques used in this paper are quite effective and can be applied to most practical Petri net models and fuzzy expert systems.

Zhang, Zipeng; Wang, Shuqing; Yuan, Xiaohui

259

Molecular targeted therapies in advanced gastric cancer: does tumor histology matter?  

PubMed Central

It is increasingly recognized that gastric cancer is a heterogeneous disease which may be divided into subgroups based on histological, anatomical, epidemiological and molecular classifications. Distinct molecular drivers and tumor biology, and thus different treatment targets and predictive biomarkers, may be implicated in each subtype. However, there is little evidence in the literature regarding the correlation among these different classifications, and particularly the molecular aberrations present in each subtype. In this review, we approach advanced gastric cancer (AGC) by presenting aberrant molecular pathways and their potential therapeutic targets in gastric cancer according to histological and anatomical classification, dividing gastric cancer into proximal nondiffuse, distal nondiffuse and diffuse disease. Several pathways are involved predominantly, although not exclusively, in different subtypes. This may help to explain the disappointing results of many published AGC trials in which study populations were heterogeneous regardless of clinicopathological characteristics of the primary tumor. Histological and anatomical classification may provide insights into tumor biology and facilitate selection of an enriched patient population for targeted agents in future studies and in the clinic. However, some molecular pathways implicated in gastric cancer have not been studied in correlation with histological or anatomical subtypes. Further studies are necessary to confirm the suggestion that such classification may predict tumor biology and facilitate selection of an enriched patient population for targeted agents in future studies and in the clinic.

Wong, Hilda

2013-01-01

260

New Generation of High Resolution Ultrasonic Imaging Technique for Advanced Material Characterization: Review  

NASA Astrophysics Data System (ADS)

The role of non-destructive material characterization and NDT is changing at a rapid rate, continuing to evolve alongside the dramatic development of novel techniques based on the principles of high-resolution imaging. The modern use of advanced optical, thermal, ultrasonic, laser-ultrasound, acoustic emission, vibration, electro-magnetic, and X-ray techniques, etc., as well as refined measurement and signal/data processing devices, allows for continuous generation of on-line information. As a result real-time process monitoring can be achieved, leading to the more effective and efficient control of numerous processes, greatly improving manufacturing as a whole. Indeed, concurrent quality inspection has become an attainable reality. With the advent of new materials for use in various structures, joints, and parts, however, innovative applications of modern NDT imaging techniques are necessary to monitor as many stages of manufacturing as possible. Simply put, intelligent advance manufacturing is impossible without actively integrating modern non-destructive evaluation into the production system.

Maev, R. Gr.

261

Molecular and therapeutic advances in the diagnosis and management of malignant pheochromocytomas and paragangliomas.  

PubMed

Pheochromocytomas (PCCs) and paragangliomas (PGLs) are rare catecholamine-secreting tumors derived from chromaffin cells originating in the neural crest. These tumors represent a significant diagnostic and therapeutic challenge because the diagnosis of malignancy is frequently made in retrospect by the development of metastatic or recurrent disease. Complete surgical resection offers the only potential for cure; however, recurrence can occur even after apparently successful resection of the primary tumor. The prognosis for malignant disease is poor because traditional treatment modalities have been limited. The last decade has witnessed exciting discoveries in the study of PCCs and PGLs; advances in molecular genetics have uncovered hereditary and germline mutations of at least 10 genes that contribute to the development of these tumors, and increasing knowledge of genotype-phenotype interactions has facilitated more accurate determination of malignant potential. Elucidating the molecular mechanisms responsible for malignant transformation in these tumors has opened avenues of investigation into targeted therapeutics that show promising results. There have also been significant advances in functional and radiological imaging and in the surgical approach to adrenalectomy, which remains the mainstay of treatment for PCC. In this review, we discuss the currently available diagnostic and therapeutic options for patients with malignant PCCs and PGLs and detail the molecular rationale and clinical evidence for novel and emerging diagnostic and therapeutic strategies. PMID:23576482

Lowery, Aoife J; Walsh, Siun; McDermott, Enda W; Prichard, Ruth S

2013-04-10

262

Advances and applications of the digital mask technique in particle image velocimetry experiments  

NASA Astrophysics Data System (ADS)

Some advancements of the digital mask technique, which was first described by Gui and Merzkirch (1996a ERCOFTAC Bull. 30 45-8) for a phase-separated evaluation of two-phase flow particle image velocimetry (PIV) recordings, are presented in this paper. The originally minimum-quadratic-difference- (MQD-) based mask technique is accelerated by using the fast Fourier transformation algorithm. In order to further increase the evaluation speed and the measurement accuracy, the digital mask technique is modified so that it can be combined with the correlation-based central difference image correction (CDIC) method, which is proved to be a more accurate and less peak-locked evaluation algorithm than both the MQD tracking method and the correlation-based tracking method. An ellipse-shaped interrogation window is constructed with the digital mask technique to improve the spatial resolution of the evaluation without loss of the evaluation accuracy. Applications in PIV measurements of solid/water two-phase flow, bubbly water flow, flow around a human blood cell and airflow near the tip of a vibrating cantilever demonstrate that the combination of the digital mask technique, the CDIC algorithm and the ellipse interrogation window makes a powerful tool for evaluating digital PIV recordings of complex flows.

Gui, L.; Wereley, S. T.; Kim, Y. H.

2003-10-01

263

Recent advances in enrichment techniques for trace analysis in capillary electrophoresis.  

PubMed

CE is gaining great popularity as a well-established separation technique for many fields such as pharmaceutical research, clinical application, environmental monitoring, and food analysis, owing to its high resolving power, rapidity, and small amount of samples and reagents required. However, the sensitivity in CE analysis is still considered as being inferior to that in HPLC analysis. Diverse enrichment methods and techniques have been increasingly developed for overcoming this issue. In this review, we summarize the recent advances in enrichment techniques containing off-line preconcentration (sample preparation) and on-line concentration (sample stacking) to enhancing sensitivity in CE for trace analysis over the last 5 years. Some relatively new cleanup and preconcentration methods involving the use of dispersive liquid-liquid microextraction, supercritical fluid extraction, matrix solid-phase dispersion, etc., and the continued use and improvement of conventional SPE, have been comprehensively reviewed and proved effective preconcentration alternatives for liquid, semisolid, and solid samples. As for CE on-line stacking, we give an overview of field amplication, sweeping, pH regulation, and transient isotachophoresis, and the coupling of multiple modes. Moreover, some limitations and comparisons related to such methods/techniques are also discussed. Finally, the combined use of various enrichment techniques and some significant attempts are proposed to further promote analytical merits in CE. PMID:23019127

Wen, Yingying; Li, Jinhua; Ma, Jiping; Chen, Lingxin

2012-09-28

264

Advances in the transient dc photocurrent technique for excited state dipole moment measurements  

NASA Astrophysics Data System (ADS)

Recent advances in the transient dc photocurrent technique for measuring excited state dipole moments, developed in our group, are discussed. A variety of approaches with detailed analyses of their advantages and disadvantages including cell design, circuit construction tricks, the data acquisition procedure, calibration, and the theoretical treatment of different conditions, are presented. Sensitivity, time resolution limitations, and newly developed features, such as the signal's dependence on light polarization as well as charge separation at interfaces are outlined. Dipole moments of a few molecules (diphenylcyclopropenone, bianthryl, dimethylaminonitrostilbene, Coumarin 153, and fluoroprobe) suitable for calibration purpose are reported-some of them for the first time.

Smirnov, Sergei N.; Braun, Charles L.

1998-08-01

265

The foreskin advancement flap: an alternative technique for reconstruction of penile burns.  

PubMed

Penile burns are devastating injuries and are frequently associated with significant functional and psychological sequelae. The goals of penile reconstruction after burn injury include: 1) skin coverage, 2) preservation of penile length, sensation and erectile function, 3) esthetic integrity, and 4) permissive for penile growth in the pediatric patient. A multitude of different techniques have been proposed, including skin grafts, local, regional, and free flaps, each of which fail to address all goals of reconstruction. We introduce the foreskin advancement flap that, when available, successfully addresses these key challenges and as such provides for an ideal reconstruction. PMID:22981384

Momeni, Arash; Abidari, Jennifer M; Karanas, Yvonne L

2012-09-14

266

New molecular targeted therapies for advanced non-small-cell lung cancer  

PubMed Central

Non-small-cell lung cancer (NSCLC) is a uniformly fatal disease and most patients will present with advanced stage. Treatment outcomes remain unsatisfactory, with low long-term survival rates. Standard treatment, such as palliative chemotherapy and radiotherapy, offers a median survival not exceeding 1 year. Hence, considerable efforts have started to be made in order to identify new biological agents which may safely and effectively be administered to advanced NSCLC patients. Two cancer cell pathways in particular have been exploited, the epidermal growth factor receptor (EGFR) and the vascular endothelial growth factor receptor (VEGFR) pathways. However, novel targeted therapies that interfere with other dysregulated pathways in lung cancer are already in the clinic. This review outlines the most promising research approaches to the treatment of NSCLC, discussed according to the specific molecular pathway targeted.

Mendez, Miriam; Custodio, Ana; Provencio, Mariano

2011-01-01

267

Recent advances in understanding the biochemical and molecular mechanism of diabetic nephropathy.  

PubMed

Diabetic nephropathy (DN) is a chronic disease characterized by proteinuria, glomerular hypertrophy, decreased glomerular filtration and renal fibrosis with loss of renal function. DN is the leading cause of end-stage renal disease, accounting for millions of deaths worldwide. Hyperglycemia is the driving force for the development of diabetic nephropathy. The exact cause of diabetic nephropathy is unknown, but various postulated mechanisms are: hyperglycemia (causing hyperfiltration and renal injury), advanced glycosylation products, activation of cytokines. In this review article, we have discussed a number of diabetes-induced metabolites such as glucose, advanced glycation end products, protein kinase C and oxidative stress and other related factors that are implicated in the pathophysiology of the DN. An understanding of the biochemical and molecular changes especially early in the DN may lead to new and effective therapies towards prevention and amelioration of DN. PMID:23541575

Sun, Yan-Ming; Su, Ying; Li, Jia; Wang, Lan-Feng

2013-03-26

268

Design of a dedicated beamline for x-ray microfocusing- and coherence- based techniques at the Advanced Photon Source.  

National Technical Information Service (NTIS)

A dedicated insertion-device beamline has been designed and is being constructed at the Advanced Photon Source (APS) for development of x- ray microfocusing- and coherence-based techniques and applications. Important parameters considered in this design i...

W. Yun B. Lai D. Shu A. Khounsary J. Cai

1995-01-01

269

Advanced Fluidic Controls for Integrated Propulsion Systems. Part 2. Materials and Fabrication Techniques for High Temperature Turbine Engine Controls.  

National Technical Information Service (NTIS)

An investigation of materials and fabrication techniques for fluidic components used in fluidic fuel control systems for advanced propulsion systems was conducted. The program consisted of: (1) materials selection, (2) materials evaluation and (3) fabrica...

K. E. Solie L. L. Sherwood R. F. Waters

1968-01-01

270

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

271

The Advanced Light Source: A new tool for research in atomic and molecular physics  

SciTech Connect

The Advanced Light Source at the Lawrence Berkeley Laboratory will be the world's brightest synchrotron radiation source in the extreme ultraviolet and soft x-ray regions of the spectrum when it begins operation in 1993. It will be available as a national user facility to researchers in a broad range of disciplines, including materials science, atomic and molecular physics, chemistry, biology, imaging, and technology. The high brightness of the ALS will be particularly well suited to high-resolution studies of tenuous targets, such as excited atoms, ions, and clusters. 13 figs., 4 tabs.

Schlachter, F.; Robinson, A.

1991-04-01

272

Charge mitigation techniques using glow and corona discharges for advanced gravitational wave detectors  

NASA Astrophysics Data System (ADS)

Charging of silica test masses in gravitational wave detectors could potentially become a significant low-frequency noise source for advanced detectors. Charging noise has already been observed and confirmed in the GEO600 detector and is thought to have been observed in one of the LIGO detectors. In this paper, two charge mitigation techniques using glow and corona discharges were investigated to create repeatable and robust procedures. The glow discharge procedure was used to mitigate charge under vacuum and would be intended to be used in the instance where an optic has become charged while the detector is in operation. The corona discharge procedure was used to discharge samples at atmospheric pressure and would be intended to be used to discharge the detector optics during the cleaning of the optics. Both techniques were shown to reduce both polarities of surface charge on fused silica to a level that would not limit advanced LIGO. Measurements of the transmission of samples that had undergone the charge mitigation procedures showed no significant variation in transmission, at a sensitivity of ~ 200 ppm, in TiO2-doped Ta2O5/SiO2 multi-layer coated fused silica.

Campsie, P.; Cunningham, L.; Hendry, M.; Hough, J.; Reid, S.; Rowan, S.; Hammond, G. D.

2011-11-01

273

Molecular Dynamics of Synthetic Based Lubricant System by Spectroscopic Techniques - Part 1  

Microsoft Academic Search

This paper describes the structure-property relationships of synthetic pentaerythritol polyol esters (PEE) and Poly Alpha Olefins (PAO) as established by the diffusion and mobility measurement and tilt angle results obtained by NMR and IR spectroscopic techniques respectively. The diffusion coefficients (D) have been found to be dependent on the molecular structure, alkyl chain length, shape and size, hydrodynamic volume and

A. S. Sarpal; M. I. S. Sastry; Ravindra Kumar; Sanker Bhadhavath; Kavita Rai; V. Bansal; M. B. Patel

2012-01-01

274

Comparative techniques for molecular weight evaluation of poly (ethylene terephthalate) (PET)  

Microsoft Academic Search

The molecular weight evaluation of poly(ethylene terephthalate) (PET) from different sources was accomplished by using three different techniques: solution intrinsic viscosity, intrinsic viscosity from melt flow index (MFI) and size exclusion chromatography (SEC). Five PET samples were used: commercial virgin PET, designed for bottle production (BPET); virgin PET taken from the first stage of condensation polymerization, similar to fiber grade

N. B. Sanches; M. L. Dias; E. B. A. V. Pacheco

2005-01-01

275

Uniformly sized ?-cyclodextrin molecularly imprinted microspheres prepared by a novel surface imprinting technique for ursolic acid  

Microsoft Academic Search

A novel surface imprinting technique was reported to synthesize uniformly sized molecularly imprinted microspheres (MIMs) using ursolic acid (UA) as the template. Three kinds of MIMs were prepared using uniformly sized functionalized poly (glycidyl methacrylate) microspheres (F-PGMA) as the support matrix. Adsorption experiments indicated the imprinting factor of MIMs-1 prepared with bonded ?-cyclodextrin (?-CD) and acrylamide (AA) in combination was

Hanmao Liu; Chunhai Liu; Xiaojing Yang; Songjun Zeng; Yuanqin Xiong; Weijian Xu

2008-01-01

276

THE USE OF FTA CARDS IN MOLECULAR DIAGNOSIS TECHNIQUES FOR BRUCELLOSIS  

Technology Transfer Automated Retrieval System (TEKTRAN)

There has recently been increased interest in the development of molecular-based diagnostic techniques for the identification and fingerprinting of Brucella isolates. One impediment for this technology is sample preparation, since most methods (especially PCR-based methods) are very sensitive to inh...

277

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

278

Advances in the systemic treatment of neuroendocrine tumors in the era of molecular therapy.  

PubMed

Neuroendocrine tumors (NETs) are heterogeneous in underlying tumor biology and clinical presentations. They are generally classified according to their degree of differentiation and sites of origin. Moreover, NETs are further characterized by their secreted bioactive neuroamine. The treatment paradigm used to be surgical intervention in early disease and mostly palliative nature in the metastatic setting. With an increase in the understanding of the molecular signaling pathways involved in tumor growth, there are various emerging treatment options for patients with advanced NETs. Somatostatin analogs have both anti-tumor effects as well as symptom palliation associated with the secreted neuropeptides. Peptide-radio-receptor treatment (PRRT) using radio-labeled peptides which binds to somatostatin receptor is a useful anti-tumor treatment but limited by general availability. Sunitinib, a multi-targeted tyrosine kinase inhibitor, has recently been shown to improve the survival of pancreatic NETs patients. Similarly, the use of an mTOR inhibitor--everolimus, either alone or in combination with somatostatin analogs have demonstrated encouraging efficacy in treating advanced NETs. The success of these two agents in pancreatic NETS supports the notion that targeting angiogenesis and/or PI3K/AKT/mTOR pathway is an important strategy for making therapeutic advances in this disease. There are now many ongoing trials in exploring the role of other novel agents in treating patients with pancreatic NETs or carcinoid. The major plaguing problem in this era is the differential response to biological agents amongst NETs of different anatomical origins. Pancreatic NETs are generally more responsive to both chemotherapy and targeted agents than NETs of other sites. Thus, the development of potential predictive and prognostic biomarkers to tailor various molecular therapies to different NETs populations is a major unmet need. PMID:23092266

Leung, Roland; Lang, Brian; Wong, Hilda; Chiu, Joanne; Yat, Wan K; Shek, Tony; Cho, Woo Y; Yau, Lo C; Yau, Thomas

2013-03-01

279

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

280

Advanced metrology techniques for the characterization of EUV mask blank defects  

NASA Astrophysics Data System (ADS)

Characterization of defects and their sources is essential for developing mitigation solutions to support the production of defect-free extreme ultraviolet (EUV) mask blanks. Enhancements to cleaning processes and the deposition tool are proving to decrease the defect density on mask blanks, and the resulting defect trends can be tracked to determine the effectiveness of these improvements. While standard defect characterization methods such as atomic force microscopy (AFM) and scanning electron microscopy (SEM) can provide useful information for large defects, sub-100 nm defects pose challenges to the current conventional metrology techniques. To address the study of these nanoscale defects, SEMATECH's Mask Blank Development Center (MBDC) houses advanced metrology capabilities that include Auger electron spectroscopy (AES) and high resolution transmission electron microscopy (TEM). Both techniques are providing enhanced compositional analysis capabilities for defect reduction efforts. TEM is proving to be a valuable technique for defect mitigation and is currently supporting many other projects including substrate smoothing activities, deposition simulation development, and defect printability studies. The rising issues with the metrology of increasingly small EUV mask blank defects will be outlined, and comprehensive characterization results using TEM and AES on EUV mask blank defects will be presented.

Harris-Jones, Jenah; Jindal, Vibhu; Lin, C. C.; Chakraborty, Tonmoy; Stinzianni, Emilio; Teki, Ranganath; Kwon, Hyuk Joo

2012-02-01

281

Recent advances in cytogenetics and molecular biology of adult hepatocellular tumors: implications for imaging and management.  

PubMed

Focal nodular hyperplasia (FNH), hepatocellular adenoma (HCA), and hepatocellular carcinoma (HCC) compose hepatocellular neoplasms that occur in adults. These tumors demonstrate characteristic epidemiologic and histopathologic features and clinical and imaging manifestations. HCAs are monoclonal neoplasms characterized by increased predilection to hemorrhage or rupture and occasional transformation to HCC. On the other hand, FNH is a polyclonal tumorlike lesion that occurs in response to increased perfusion and has an indolent clinical course. Up to 90% of HCCs occur in the setting of cirrhosis. Chronic viral hepatitis (hepatitis B and hepatitis C) infection and metabolic syndrome are major risk factors that can induce HCCs in nonfibrotic liver. Recent advances in pathology and genetics have led to better understanding of the histogenesis, natural history, and molecular events that determine specific oncologic pathways used by these neoplasms. HCAs are now believed to result from specific genetic mutations involving TCF1 (transcription factor 1 gene), IL6ST (interleukin 6 signal transducer gene), and CTNNB1 (? catenin-1 gene); FNHs are characterized by an "imbalance" of angiopoietin. While the ? catenin signaling pathway is associated with well- and moderately differentiated HCCs, mutations involving p53 (tumor protein 53 gene), MMP14 (matrix metalloproteinase 14 gene), and RhoC (Ras homolog gene family, member C) are associated with larger tumor size, higher tumor grade with resultant shortened tumor-free survival, and poor prognosis. Fibrolamellar carcinoma (FLC), a unique HCC subtype, exhibits genomic homogeneity that partly explains its better overall prognosis. On the basis of recent study results involving cytogenetics and oncologic pathways of HCCs, novel drugs that act against molecular targets are being developed. Indeed, sorafenib (a multikinase inhibitor) is currently being used in the successful treatment of patients with advanced HCC. Characterization of genetic abnormalities and genotype-phenotype correlations in adult hepatocellular tumors provides better understanding of tumor pathology and biology, imaging findings, prognosis, and response to molecular therapeutics. PMID:21339346

Shanbhogue, Alampady K; Prasad, Srinivasa R; Takahashi, Naoki; Vikram, Raghunandan; Sahani, Dushyant V

2011-03-01

282

Molecular screening for a personalized treatment approach in advanced adrenocortical cancer.  

PubMed

Context: Adrenocortical cancer (ACC) is a rare cancer with poor prognosis and scant treatment options. In ACC, no personalized approach has emerged but no extensive molecular screening has been performed to date. Objective: The objective of the study was to evaluate the presence of a large number of potentially targetable molecular events in a large cohort of advanced ACC. Design, Setting, and Participants: We used hot spot gene sequencing (Ion Torrent, 40 patients) and comparative genomic hybridization (CGH; 28 patients; a subset of the entire cohort) in adult stage III-IV ACC samples to screen for mutations and copy number abnormalities of potential interest for therapeutic use in 46 and 130 genes, respectively. Results: At least one copy number alteration or mutation was found in 19 patients (47.5%). The most frequent mutations were detected on TP53, ATM, and CTNNB1 [6 of 40 (15%), 5 of 40 (12.5%), and 4 of 40 (10%), respectively]. The most frequent copy number alterations identified were: amplification of the CDK4 oncogene (5 of 28; 17.9%) and deletion of the CDKN2A (4 of 28; 14.3%) and CDKN2B (3 of 28; 10.7%) tumor suppressor genes. Amplifications of FGFR1, FGF9, or FRS2 were discovered in three subjects (10.7%). Associated alterations were: deletions of CDKN2A, CDKN2B with ATM mutations, and TP53 mutations with CTNNB1 mutations. Conclusions: No simple targetable molecular event emerged. Drugs targeting the cell cycle could be the most relevant new therapeutic approach for patients with advanced ACC. Inhibitors of the fibroblast growth factor receptor pathway could also be a therapeutic option in a subset of patients, whereas other targeted therapies should be considered on a case-by-case basis. PMID:23979958

De Martino, Maria Cristina; Al Ghuzlan, Abir; Aubert, Sebastien; Assié, Guillaume; Scoazec, Jean-Yves; Leboulleux, Sophie; Do Cao, Christine; Libè, Rossella; Nozières, Cécile; Lombès, Marc; Pattou, François; Borson-Chazot, Francoise; Hescot, Ségolène; Mazoyer, Clement; Young, Jacques; Borget, Isabelle; Colao, Annamaria; Pivonello, Rosario; Soria, Jean-Charles; Bertherat, Jerome; Schlumberger, Martin; Lacroix, Ludovic; Baudin, Eric

2013-08-26

283

Biosynthesis of polyunsaturated Fatty acids in marine invertebrates: recent advances in molecular mechanisms.  

PubMed

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

2013-10-21

284

Molecular subtype analysis determines the association of advanced breast cancer in Egypt with favorable biology  

PubMed Central

Background Prognostic markers and molecular breast cancer subtypes reflect underlying biological tumor behavior and are important for patient management. Compared to Western countries, women in North Africa are less likely to be prognosticated and treated based on well-characterized markers such as the estrogen receptor (ER), progesterone receptor (PR) and Her2. We conducted this study to determine the prevalence of breast cancer molecular subtypes in the North African country of Egypt as a measure of underlying biological characteristics driving tumor manifestations. Methods To determine molecular subtypes we characterized over 200 tumor specimens obtained from Egypt by performing ER, PR, Her2, CK5/6, EGFR and Ki67 immunohistochemistry. Results Our study demonstrated that the Luminal A subtype, associated with favorable prognosis, was found in nearly 45% of cases examined. However, the basal-like subtype, associated with poor prognosis, was found in 11% of cases. These findings are in sharp contrast to other parts of Africa in which the basal-like subtype is over-represented. Conclusions Egyptians appear to have favorable underlying biology, albeit having advanced disease at diagnosis. These data suggest that Egyptians would largely profit from early detection of their disease. Intervention at the public health level, including education on the benefits of early detection is necessary and would likely have tremendous impact on breast cancer outcome in Egypt.

2011-01-01

285

STAR-LITE (Safe Techniques Advance Research - Laboratory Interactive Training Environment)  

NSDL National Science Digital Library

The National Institutes of Health, Division of Occupational Health and Safety (DOHS) developed a laboratory safety training program called STAR-LITE (Safe Techniques Advance Research â Laboratory Interactive Training Environment.) STAR-LITE is an interactive computer-based laboratory safety training program for high school students and undergraduate university students. The program incorporates common features seen in todayâs video games, i.e., selection of an individualized character; first-person views; and three-dimensional graphics. The method of instruction integrates visualization of consequences, e.g., slips/trips/falls, inhalation of chemical hazards, spills of biohazardous liquids, development of critical-thinking proficiencies, and application of problem-solving skills.

Group, Janus R.

286

Fast Benchtop Fabrication of Laminar Flow Chambers for Advanced Microscopy Techniques  

PubMed Central

Background Fluid handling technology is acquiring an ever more prominent place in laboratory science whether it is in simple buffer exchange systems, perfusion chambers, or advanced microfluidic devices. Many of these applications remain the providence of laboratories at large institutions with a great deal of expertise and specialized equipment. Even with the expansion of these techniques, limitations remain that frequently prevent the coupling of controlled fluid flow with other technologies, such as coupling microfluidics and high-resolution position and force measurements by optical trapping microscopy. Method Here we present a method for fabrication of multiple-input laminar flow devices that are optically clear [glass] on each face, chemically inert, reusable, inexpensive, and can be fabricated on the benchtop in approximately one hour. Further these devices are designed to allow flow regulation by a simple gravity method thus requiring no specialized equipment to drive flow. Here we use these devices to perform total internal reflection fluorescence microscopy measurements as well as position sensitive optical trapping experiments. Significance Flow chamber technology needs to be more accessible to the general scientific community. The method presented here is versatile and robust. These devices use standard slides and coverslips making them compatible with nearly all types and models of light microscopes. These devices meet the needs of groups doing advanced optical trapping experiments, but could also be adapted by nearly any lab that has a function for solution flow coupled with microscopy.

Courson, David S.; Rock, Ronald S.

2009-01-01

287

Thin-layer chromatography, overlay technique and mass spectrometry: a versatile triad advancing glycosphingolipidomics.  

PubMed

Much effort is currently invested in the development of mass spectrometry-based strategies for investigating the entirety of glycosphingolipids (GSLs) of a certain cell type, tissue, organ or body encompassing the respective glycosphingolipidome. As part of the investigation of the vertebrate glycosphingolipidome, GSL analysis is undergoing rapid expansion owing to the application of novel mass spectrometry techniques acting as the linchpin in the network of collaborations challenged to unravel structural and functional aspects of GSLs. Difficulties may arise in the determination of the exact structures of GSLs due to the heterogeneity of the sugar moiety varying in the number and sequence of monosaccharides, and their anomeric configuration and linkage type, which make up the principal items of the glyco code of biologically active carbohydrate chains. The ceramide variability caused by the diversity of the long-chain amino alcohol and the fatty acid, which both may vary in chain length, degree of unsaturation, and type and number of substituents, further contributes to the increasing number of possible GSL species. In view of this heterogeneity, a single-method analytical mass spectrometry (MS) technique without auxiliary tools yields limited data, providing only partial structural information of individual GSLs in complex mixtures. Approaching this challenge, current advances on a triad system matching three complementary methods are described in this review: (i) silica gel based TLC separation of GSLs, (ii) their overlay detection on the TLC plate (mostly based on antibody-mediated recognition), and (iii) direct and indirect MS based structural characterization, i.e. directly on the TLC plate or in lipid extracts from silica gel. We will focus on recent improvements by employing antibodies, AB(5) toxins and bacteria for direct IR-MALDI-o-TOF MS and indirect ESI-QTOF MS analysis of GSLs. We believe that the combinatorial approach using conventional TLC and modern mass spectrometry provides a developmental advance in exploring the glycosphingolipidome of biological material. PMID:21549856

Meisen, Iris; Mormann, Michael; Müthing, Johannes

2011-04-23

288

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

289

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

290

Advances in functional X-ray imaging techniques and contrast agents  

PubMed Central

X-rays have been used for non-invasive high-resolution imaging of thick biological specimens since their discovery in 1895. They are widely used for structural imaging of bone, metal implants, and cavities in soft tissue. Recently, a number of new contrast methodologies have emerged which are expanding X-ray’s biomedical applications to functional as well as structural imaging. These techniques are promising to dramatically improve our ability to study in situ biochemistry and disease pathology. In this review, we discuss how X-ray absorption, X-ray fluorescence, and X-ray excited optical luminescence can be used for physiological, elemental, and molecular imaging of vasculature, tumours, pharmaceutical distribution, and the surface of implants. Imaging of endogenous elements, exogenous labels, and analytes detected with optical indicators will be discussed.

Chen, Hongyu; Rogalski, Melissa M.

2012-01-01

291

ELUCIDATION OF THE MICROBIAL COMMUNITY STRUCTURE WITHIN A LABORATORY-SCALE ACTIVATED SLUDGE PROCESS USING MOLECULAR TECHNIQUES  

Microsoft Academic Search

The microbial community present in a laboratory-scale aerobic and anoxic activated sludge system was investigated using a combination of novel molecular techniques. The parent system was operated for a duration of one year and samples were taken at regular intervals to determine the microbial community structure and profile. The combination of molecular techniques included fluorescent in situ hybridisation (FISH) and

P. Padayachee; A. Ismail; F. Bux

292

Recent advances in endovascular techniques for management of acute nonvariceal upper gastrointestinal bleeding  

PubMed Central

Over the past two decades, transcatheter arterial embolization has become the first-line therapy for the management of upper gastrointestinal bleeding that is refractory to endoscopic hemostasis. Advances in catheter-based techniques and newer embolic agents, as well as recognition of the effectiveness of minimally invasive treatment options, have expanded the role of interventional radiology in the management of hemorrhage for a variety of indications, such as peptic ulcer bleeding, malignant disease, hemorrhagic Dieulafoy lesions and iatrogenic or trauma bleeding. Transcatheter interventions include the following: selective embolization of the feeding artery, sandwich coil occlusion of the gastroduodenal artery, blind or empiric embolization of the supposed bleeding vessel based on endoscopic findings and coil pseudoaneurysm or aneurysm embolization by three-dimensional sac packing with preservation of the parent artery. Transcatheter embolization is a fast, safe and effective, minimally invasive alternative to surgery when endoscopic treatment fails to control bleeding from the upper gastrointestinal tract. This article reviews the various transcatheter endovascular techniques and devices that are used in a variety of clinical scenarios for the management of hemorrhagic gastrointestinal emergencies.

Loffroy, Romaric F; Abualsaud, Basem A; Lin, Ming D; Rao, Pramod P

2011-01-01

293

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

294

EPS in Environmental Microbial Biofilms as Examined by Advanced Imaging Techniques  

NASA Astrophysics Data System (ADS)

Biofilm communities are highly structured associations of cellular and polymeric components which are involved in biogenic and geogenic environmental processes. Furthermore, biofilms are also important in medical (infection), industrial (biofouling) and technological (biofilm engineering) processes. The interfacial microbial communities in a specific habitat are highly dynamic and change according to the environmental parameters affecting not only the cellular but also the polymeric constituents of the system. Through their EPS biofilms interact with dissolved, colloidal and particulate compounds from the bulk water phase. For a long time the focus in biofilm research was on the cellular constituents in biofilms and the polymer matrix in biofilms has been rather neglected. The polymer matrix is produced not only by different bacteria and archaea but also by eukaryotic micro-organisms such as algae and fungi. The mostly unidentified mixture of EPS compounds is responsible for many biofilm properties and is involved in biofilm functionality. The chemistry of the EPS matrix represents a mixture of polymers including polysaccharides, proteins, nucleic acids, neutral polymers, charged polymers, amphiphilic polymers and refractory microbial polymers. The analysis of the EPS may be done destructively by means of extraction and subsequent chemical analysis or in situ by means of specific probes in combination with advanced imaging. In the last 15 years laser scanning microscopy (LSM) has been established as an indispensable technique for studying microbial communities. LSM with 1-photon and 2-photon excitation in combination with fluorescence techniques allows 3-dimensional investigation of fully hydrated, living biofilm systems. This approach is able to reveal data on biofilm structural features as well as biofilm processes and interactions. The fluorescent probes available allow the quantitative assessment of cellular as well as polymer distribution. For this purpose lectin-binding- analysis has been suggested as a suitable approach to image glycoconjugates within the polymer matrix of biofilm communities. More recently synchrotron radiation is increasingly recognized as a powerful tool for studying biological samples. Hard X-ray excitation can be used to map elemental composition whereas IR imaging allows examination of biological macromolecules. A further technique called soft X-ray scanning transmission microscopy (STXM) has the advantage of both techniques and may be employed to detect elements as well as biomolecules. Using the appropriate spectra, near edge X-ray absorption fine structure (NEXAFS) microscopy allows quantitative chemical mapping at 50 nm resolution. In this presentation the applicability of LSM and STXM will be demonstrated using several examples of different environmental biofilm systems. The techniques in combination provide a new view of complex microbial communities and their interaction with the environment. These advanced imaging techniques offer the possibility to study the spatial structure of cellular and polymeric compounds in biofilms as well as biofilm microhabitats, biofilm functionality and biofilm processes.

Neu, T. R.; Lawrence, J. R.

2006-12-01

295

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

296

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.

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

2011-01-01

297

The Synergy Between Total Scattering and Advanced Simulation Techniques: Quantifying Geopolymer Gel Evolution  

SciTech Connect

With the ever increasing demands for technologically advanced structural materials, together with emerging environmental consciousness due to climate change, geopolymer cement is fast becoming a viable alternative to traditional cements due to proven mechanical engineering characteristics and the reduction in CO2 emitted (approximately 80% less CO2 emitted compared to ordinary Portland cement). Nevertheless, much remains unknown regarding the kinetics of the molecular changes responsible for nanostructural evolution during the geopolymerization process. Here, in-situ total scattering measurements in the form of X-ray pair distribution function (PDF) analysis are used to quantify the extent of reaction of metakaolin/slag alkali-activated geopolymer binders, including the effects of various activators (alkali hydroxide/silicate) on the kinetics of the geopolymerization reaction. Restricting quantification of the kinetics to the initial ten hours of reaction does not enable elucidation of the true extent of the reaction, but using X-ray PDF data obtained after 128 days of reaction enables more accurate determination of the initial extent of reaction. The synergies between the in-situ X-ray PDF data and simulations conducted by multiscale density functional theory-based coarse-grained Monte Carlo analysis are outlined, particularly with regard to the potential for the X-ray data to provide a time scale for kinetic analysis of the extent of reaction obtained from the multiscale simulation methodology.

White, Claire [Los Alamos National Laboratory; Bloomer, Breaunnah E. [Los Alamos National Laboratory; Provis, John L. [The University of Melbourne; Henson, Neil J. [Los Alamos National Laboratory; Page, Katharine L. [Los Alamos National Laboratory

2012-05-16

298

Combination of various analytical techniques for speciation of low molecular weight aluminium complexes in plant sap  

Microsoft Academic Search

The possibilities for speciation of low molecular weight aluminium organic acid complexes (LMW-Al) in plant sap were investigated\\u000a by applying a combination of various chromatographic and spectroscopic techniques. The behavior of different LMW-Al complexes\\u000a was investigated in synthetic aqueous solutions on anion and cation exchange fast protein liquid chromatography (FPLC) columns\\u000a with inductively coupled plasma – atomic emission spectrometry (ICP-AES)

Tjaöa Bantan; R. Mila?i?; B. Mitrovi?; Boris Pihlar

1999-01-01

299

Application of Molecular Techniques to the Elucidation of the Microbial Community Structure of Antique Paintings  

Microsoft Academic Search

This paper uses molecular techniques to describe the microstructure and microbiological communities of sixteenth century artwork\\u000a and their relationships. The microbiological populations, analysed by denaturing gradient gel electrophoresis (DGGE), were\\u000a highly influenced by the chemical composition of the pictorial layers detected by energy-dispersive X-ray analysis. DGGE revealed\\u000a that the diversity of microbial communities was lower in pictorial layers composed of

Antonio Santos; Alejandro Cerrada; Silvia García; Margarita San Andrés; Concepción Abrusci; Domingo Marquina

2009-01-01

300

A structural study of praseodymium gallate glasses by combined neutron diffraction, molecular dynamics and EXAFS techniques  

NASA Astrophysics Data System (ADS)

Neutron diffraction and Extended X-ray Absorption Fine Structure (EXAFS) studies have been carried out on a range of praseodymium gallate glasses (Pr2O3-Ga2O3) prepared by aerodynamic levitation and laser heating. The short and intermediate range ordering around the rare-earth have been obtained by a multi-technique method. The results show that simple molecular dynamics simulations give a good representation of the coordination structure around the rare-earth in these glasses.

Kidkhunthod, P.; Barnes, A. C.

2009-11-01

301

Enhancing adsorptive separations by molecularly imprinted polymers: Role of imprinting techniques and system parameters  

Microsoft Academic Search

Molecularly imprinted polymers (MIPs) are gaining increasing importance in separation technology. We recently proposed the application of MIPs for the removal of trace impurities from bulk chemicals. In this communication, we report on the separation of phenol–bisphenol-A (BPA) and 2,4-dihydroxy benzophenone isomers (2,4-DHB) using surface as well as bulk imprinted polymeric adsorbents. The choice of polymer support, imprinting technique and

V. P. Joshi; M. G. Kulkarni; R. A. Mashelkar

2000-01-01

302

Molecular Imaging of Vascular Inflammation with Nanoparticles  

Microsoft Academic Search

Innovation in molecular imaging is poised to fundamentally advance the field of diagnostic medical imaging related to atherosclerosis.\\u000a By detecting molecular signatures and cellular processes in vivo, advanced molecular imaging techniques offer a highly sensitive\\u000a means to diagnose disease perhaps at preclinical stages. In conjunction with advances in imaging capability, materials science,\\u000a and synthetic chemistry, nanoparticles have emerged as molecular

Arun K. Thukkani; Charles Glaus; Michael J. Welch

2010-01-01

303

Inter-kingdom encounters: recent advances in molecular bacterium-fungus interactions.  

PubMed

Interactions between bacteria and fungi are well known, but it is often underestimated how intimate and decisive such associations can be with respect to behaviour and survival of each participating organism. In this article we review recent advances in molecular bacterium-fungus interactions, combining the data of different model systems. Emphasis is given to the positive or negative consequences these interactions have on the microbe accommodating plants and animals. Intricate mechanisms of antagonism and tolerance have emerged, being as important for the biological control of plants against fungal diseases as for the human body against fungal infections. Bacterial growth promoters of fungal mycelium have been characterized, and these may as well assist plant-fungus mutualism as disease development in animals. Some of the toxins that have been previously associated with fungi are actually produced by endobacteria, and the mechanisms that lie behind the maintenance of such exquisite endosymbioses are fascinating. Bacteria do cause diseases in fungi, and a synergistic action between bacterial toxins and extracellular enzymes is the hallmark of such diseases. The molecular study of bacterium-fungus associations has expanded our view on microbial communication, and this promising field shows now great potentials in medicinal, agricultural and biotechnological applications. PMID:19337734

Tarkka, Mika T; Sarniguet, Alain; Frey-Klett, Pascale

2009-04-01

304

Apoptosis: A Four-Week Laboratory Investigation for Advanced Molecular and Cellular Biology Students  

PubMed Central

Over the past decade, apoptosis has emerged as an important field of study central to ongoing research in many diverse fields, from developmental biology to cancer research. Apoptosis proceeds by a highly coordinated series of events that includes enzyme activation, DNA fragmentation, and alterations in plasma membrane permeability. The detection of each of these phenotypic changes is accessible to advanced undergraduate cell and molecular biology students. We describe a 4-week laboratory sequence that integrates cell culture, fluorescence microscopy, DNA isolation and analysis, and western blotting (immunoblotting) to follow apoptosis in cultured human cells. Students working in teams chemically induce apoptosis, and harvest, process, and analyze cells, using their data to determine the order of events during apoptosis. We, as instructors, expose the students to an environment closely simulating what they would encounter in an active cell or molecular biology research laboratory by having students coordinate and perform multiple tasks simultaneously and by having them experience experimental design using current literature, data interpretation, and analysis to answer a single question. Students are assessed by examination of laboratory notebooks for completeness of experimental protocols and analysis of results and for completion of an assignment that includes questions pertaining to data interpretation and apoptosis.

DiBartolomeis, Susan M.; Mone, James P.

2003-01-01

305

Associating phenotypes with molecular events: recent statistical advances and challenges underpinning microarray experiments.  

PubMed

Progress in mapping the genome and developments in array technologies have provided large amounts of information for delineating the roles of genes involved in complex diseases and quantitative traits. Since complex phenotypes are determined by a network of interrelated biological traits typically involving multiple inter-correlated genetic and environmental factors that interact in a hierarchical fashion, microarrays hold tremendous latent information. The analysis of microarray data is, however, still a bottleneck. In this paper, we review the recent advances in statistical analyses for associating phenotypes with molecular events underpinning microarray experiments. Classical statistical procedures to analyze phenotypes in genetics are reviewed first, followed by descriptions of the statistical procedures for linking molecular events to measured gene expression phenotypes (microarray-based gene expression) and observed phenotypes such as diseases status. These statistical procedures include (1) prior analysis, such as data quality controls, and normalization analyses for minimizing the effects of experimental artifacts and random noise; (2) gene selections and differentiation procedures based on inferential statistics for the class comparisons; (3) dynamic temporal patterns analysis through exploratory statistics such as unsupervised clustering and supervised classification and predictions; (4) assessing the reliability of microarray studies using real-time PCR and the reproducibility issues from many studies and multiple platforms. In addition, the post analysis to associate the discovered patterns of gene expression to pathway and functional analysis for selected genes are also considered in order to increase our understanding of interconnected gene processes. PMID:16292543

Liang, Yulan; Kelemen, Arpad

2005-11-15

306

The "Jacobsen flap" technique: a safe, simple surgical procedure to treat Dupuytren disease of the little finger in advanced stage.  

PubMed

The surgery for advanced stages of Dupuytren disease of the little finger is controversial. In the literature, several techniques have been described with variable reported results and postoperative complications. Percutaneous needle fasciotomy, McCash technique, and dermofasciectomy are often performed for surgical treatment but they present significant complications and limits. This study reviews our experience of using the Jacobsen flap technique, a modification of the McCash procedure. We found that the Jacobsen flap technique for the significant correction of the contracture, the low rate of complications, and the relatively simple surgical approach is an excellent alternative to percutaneous needle fasciotomy, dermofasciectomy, or amputation. PMID:20818219

Tripoli, Massimiliano; Cordova, Adriana; Moschella, Francesco

2010-09-01

307

Strategies for improved accuracy and efficiency with advanced intensity modulated radiation therapy techniques  

NASA Astrophysics Data System (ADS)

The development of advanced intensity modulated radiation therapy (IMRT) techniques has led to significant improvements in our ability to treat complicated target volumes with minimal collateral damage to the surrounding healthy tissue. These techniques however, come at the cost of increased complexity; which translates into increased sensitivity of the optimized treatment plans to inaccuracies in the planning and delivery processes, and can also result in longer treatment times. The aim of this work is investigate various strategies designed to improve the accuracy and efficiency of two advanced forms of IMRT: helical tomotherapy and intensity modulated proton therapy (IMPT). Helical tomotherapy is form of X-ray IMRT that uses a compact linear accelerator mounted on a CT ring gantry to rotationally deliver intensity modulated fan-beams of radiation to a patient for treatment. Failure to select judicious values for certain planning parameters can result in plans with long treatment times that are difficult for the machine to accurately deliver. This situation was observed for a series of patients scheduled for treatment at the University of Wisconsin. Treatment planning methods designed to avoid these difficulties have been investigated and are discussed. While the vast majority of IMRT treatments are performed using mega-voltage X-rays, there has recently been a great deal of interest in the use of IMPT for a variety of clinical indications. Current methods of IMPT are limited in their applicability however, due to restrictions imposed by the current delivery paradigm. An alternative method for IMPT delivery using a fan-beam geometry has been examined. Another challenge with IMPT pertains to the accuracy of proton dose calculations in the presence of complex tissue heterogeneities. Monte Carlo methods provide the most accurate means of dose calculation; however, the computational requirements of current radiation transport codes makes Monte Carlo methods unsuitable for routine treatment planning. As an alternative, analytical pencil beam algorithms are used to calculate dose. For this work, an analytical proton dose calculator was developed. Two heterogeneity correction schemes have been incorporated into the algorithm and the accuracy of these methods compared with Monte Carlo is examined in a variety of heterogeneous phantom geometries.

Westerly, David C.

308

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

309

Penicillium marneffei Infection and Recent Advances in the Epidemiology and Molecular Biology Aspects  

PubMed Central

Penicillium marneffei infection is an important emerging public health problem, especially among patients infected with human immunodeficiency virus in the areas of endemicity in southeast Asia, India, and China. Within these regions, P. marneffei infection is regarded as an AIDS-defining illness, and the severity of the disease depends on the immunological status of the infected individual. Early diagnosis by serologic and molecular assay-based methods have been developed and are proving to be important in diagnosing infection. The occurrence of natural reservoirs and the molecular epidemiology of P. marneffei have been studied; however, the natural history and mode of transmission of the organism remain unclear. Soil exposure, especially during the rainy season, has been suggested to be a critical risk factor. Using a highly discriminatory molecular technique, multilocus microsatellite typing, to characterize this fungus, several isolates from bamboo rats and humans were shown to share identical multilocus genotypes. These data suggest either that transmission of P. marneffei may occur from rodents to humans or that rodents and humans are coinfected from common environmental sources. These putative natural cycles of P. marneffei infection need further investigation. Studies on the fungal genetics of P. marneffei have been focused on the characterization of genetic determinants that may play important roles in asexual development, mycelial-to-yeast phase transition, and the expression of antigenic determinants. Molecular studies have identified several genes involved in germination, hyphal development, conidiogenesis, and yeast cell polarity. A number of functionally important genes, such as the malate synthase- and catalase-peroxidase protein-encoding genes, have been identified as being upregulated in the yeast phase. Future investigations pertaining to the roles of these genes in host-fungus interactions may provide the key knowledge to understanding the pathogenicity of P. marneffei.

Vanittanakom, Nongnuch; Cooper, Chester R.; Fisher, Matthew C.; Sirisanthana, Thira

2006-01-01

310

Advances in turbulent mixing techniques to study microsecond protein folding reactions.  

PubMed

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, Circular Dichroism, Small-Angle X-ray Scattering, Hydrogen Exchange followed by Mass Spectrometry and Nuclear Magnetic Resonance Spectroscopy, Infrared Spectroscopy (IR), and Fourier Transform IR Spectroscopy, 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 the 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, which are likely to lead to dramatic improvements in time resolution and sample consumption for CF mixers over the next few years. © 2013 Wiley Periodicals, Inc. Biopolymers 99: 888-896, 2013. PMID:23868289

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

2013-11-01

311

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

312

Evaluation of phenotypic and molecular typing techniques for determining diversity in Erwinia carotovora subspp. atroseptica.  

PubMed

A number of phenotypic and molecular fingerprinting techniques, including physiological profiling (Biolog), restriction fragment length polymorphism (RFLP), enterobacterial repetitive intergenic consensus (ERIC) and a phage typing system, were evaluated for their ability to differentiate between 60 strains of Erwinia carotovora ssp. atroseptica (Eca) from eight west European countries. These techniques were compared with other fingerprinting techniques, random amplified polymorphic DNA (RAPD) and Ouchterlony double diffusion (ODD), previously used to type this pathogen. Where possible, data were represented as dendrograms and groups/subgroups of strains identified. Simpson's index of diversity (Simpson's D) was used to compare groupings obtained with the different techniques which, with the exception of Biolog, gave values of 0.46 (RFLP), 0. 39 (ERIC), 0.83 (phage typing), 0.82 (RAPD) and 0.26 (ODD). Of the techniques tested, phage typing showed the highest level of diversity within Eca, and this technique will now form the basis of studies into the epidemiology of blackleg disease. PMID:10594720

Toth, I K; Bertheau, Y; Hyman, L J; Laplaze, L; López, M M; McNicol, J; Niepold, F; Persson, P; Salmond, G P; Sletten, A; van Der Wolf, J M; Pérombelon, M C

1999-11-01

313

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

314

Support for NATO Advanced Study Institute on molecular ecology of aquatic microbes, August 28--September 9, 1994. Final report.  

National Technical Information Service (NTIS)

This is a summary paper for a NATO Advanced Study Institute sponsored meeting entitled 'The Molecular Ecology of Aquatic Microbes' held in Luccia, Italy from August 28 to September 9, 1994. A full reference book for the proceedings is to be published late...

I. Joint

1995-01-01

315

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.

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

2006-01-01

316

Femtosecond spectroscopy on simple molecular systems: pump-probe and four-wave mixing techniques  

NASA Astrophysics Data System (ADS)

Different techniques are applied in order to obtain information about ultrafast molecular and reaction dynamics. Femtosecond time-resolved pump-probe spectroscopy is used to investigate the dissociation reaction of NAI molecules. Starting from free NaI molecules, the environment is changed to solution-like conditions adding rare gas with different pressures. Femtosecond time-resolved degenerate four-wave mixing (DFWM) spectroscopy is performed in order to investigate molecular dynamics in iodine molecules in the gas phase. Depending on the timing of the laser pulses different dynamics are reflected in the DFWM transient signal. By the use of time evolution diagrams, the varying contribution of ground and excited-state dynamics can be explained conclusively. Supersonic jet-cooled potassium dimers are investigated in their electronic ground state by a femtosecond pump-probe experiment. The ground state vibrational wave packets are created by a stimulated Raman pumping process and selectively interrogated by resonance enhanced three photon ionization.

Chen, T.; Dietz, H.; Engel, V.; Heid, M.; Kiefer, W.; Knopp, G.; Materny, A.; Meyer, S.; Pausch, R.; Schmitt, M.; Schwoerer, H.; Siebert, T.

1999-01-01

317

Neutron Scattering Techniques as Advanced Structural Probes of Filled and Nanocomposite Elastomers: A Technique for the 21st Century.  

National Technical Information Service (NTIS)

The last three decades has seen the development of neutron scattering techniques as probes for the nanoscale structure of polymer filled and nanocomposite polymer systems. The objectives of these studies includes understanding filler associations, bound p...

R. P. Hjelm

2000-01-01

318

[Advanced findings on the molecular mechanisms for behavioral sensitization to psychostimulants].  

PubMed

Repeated administration of psychostimulants like methamphetamine and cocaine induce behavioral sensitization, which is recognized as an animal model for dependence and psychoses. Many previous studies have proved two major cascades play a crucial roles for molecular mechanisms underling sensitization. The first one is activation of D1 dopamine receptors by robust increase of dopamine release, followed by activation of adenylyl cyclase, increase of cyclic AMP, activation of protein kinase A (PKA) and phosphorylation of proteins by PKA. The second one is activation of NMDA receptor by enhanced release of glutamine, followed by increased intracellular Ca2+ concentration, formation of Ca2+/calmodulin complex, and phosphorylation of several proteins such as calcineurin, CaM-K II and nitric oxide synthase. Recent advanced findings on sensitization mechanisms were reviewed from three different aspects: 1) Studies using knockout mice offered quite amazing findings that D1DA-receptor-lacking mice or dopamine-transporter-lacking mice can develop sensitization and dependence, which were not consistent with the previously established hypotheses based on behavioral pharmacology. In addition, those data showed the important roles of vesicular monoamine transporter 2, 5HT1B receptors and delta FosB. 2) Research on neural-plasticity-related sensitization revealed the involvement of several molecules such as tissue plasminogen activator, arc (activity-regulated, cytoskeleton-associated), synaptophysin and stathmin. Increased expression of these genes may participate in the rearrangement of neural networks with synaptogenesis and expansion of dendrites 3) Trials to discover novel-genes-involved sensitization phenomenon using differential display or subtraction cloning found some candidate genes, mrt-1, NAC-1 and CART. Although in these areas are still in progress, accumulating findings will elucidate the details of the molecular mechanism of behavioral sensitization and dependence. PMID:11233297

Ujike, H

2001-01-01

319

Coulomb-explosion technique for determining geometrical structures of molecular ions  

SciTech Connect

Traditional experimental techniques (e.g. studies on photon absorption or emission) for determining the sterochemical structures of neutral molecules are extremeley difficult to apply to molecular ions because of problems in obtaining a sufficient spatial density of the ions to be studied. Recent high-resolution measurements on the energy and angle distributions of the fragments produced when fast (MeV) molecular-ion beams from an electrostatic accelerator dissociate (Coulomb explode) in thin foils and in gases, offer promising possibilities for deducing the sterochemical structures of the molecular ions constituting the incident beams. Bond lengths have been determined in this way for several diatomic projectiles (H/sub 2//sup +/, HeH/sup +/, CH/sup +/, NH/sup +/, OH/sup +/, N/sub 2//sup +/, O/sub 2//sup +/, etc.) with an accuracy of approx. 0.01 A. H/sub 3//sup +/ has been demonstrated (for the first time) to be equilateral triangular and the interproton distance measured. Measurements on single fragments from CO/sub 2//sup +/, N/sub 2/O/sup +/, C/sub 3/H/sub 3//sup +/, and CH/sub n//sup +/ have revealed the gross structures of the projectiles. An apparatus has recently been constructed at Argonne to permit precise measurements on fragments in coincidence. The apparatus has been tested on a known structure (OH/sub 2//sup +/). The O-H bond length was found to be 1.0 +- 0.04 A and the H-O-H bond angle was measured as 110 --- 2/sup 0/. These values are in excellent agreement with those found in optical experiments (0.999 A and 110.5/sup 0/). This Coulomb explosion technique can be expected to be refined in accuracy and to be extended to a wide range of molecular ions whose structures are inaccessible by other means.

Gemmell, D.S.

1981-01-01

320

78 FR 59927 - Next Generation Risk Assessment: Incorporation of Recent Advances in Molecular, Computational...  

Federal Register 2010, 2011, 2012, 2013

...Molecular, Computational, and Systems Biology [External Review Draft] AGENCY: Environmental...Molecular, Computational, and Systems Biology [External Review Draft]'' (EPA...Molecular, Computational, and Systems Biology [External Review Draft]'' is...

2013-09-30

321

Landslide detection and long-term monitoring in urban area by means of advanced interferometric techniques  

NASA Astrophysics Data System (ADS)

This work aims at illustrating the potential of advanced interferometric techniques for detection and long-term monitoring of landslide ground deformations at local scale. Space-born InSAR (Synthetic Aperture Radar Interferometry) has been successfully exploited in recent years to measure ground deformations associated to processes with slow kinematics, such as landslides, tectonic motions, subsidence or volcanic activity, thanks to both the standard single-interferogram approach (centimeter accuracy) and advanced time-series analyses of long temporal radar satellite data stacks (millimeter accuracy), such as Persistent Scatterers Interferometry (PSI) techniques. In order to get a complete overview and an in-depth knowledge of an investigated landslide, InSAR satellite measures can support conventional in situ data. This methodology allows studying the spatial pattern and the temporal evolution of ground deformations, improving the spatial coverage and overcoming issues related to installation of ground-based instrumentation and data acquisition in unstable areas. Here we describe the application of the above-mentioned methodology on the test area of Agrigento, Sicily (Italy), affected by hydrogeological risk. The town is located in Southern Sicily, at edge of the Apennine-Maghrebian thrust belt, on the Plio-Pleistocene and Miocene sediments of the Gela Nappe. Ground instabilities affect the urban area and involve the infrastructures of its NW side, such as the Cathedral, the Seminary and many private buildings. An integration between InSAR analyses and conventional field investigations (e.g. structural damages and fractures surveys) was therefore carried out, to support Regional Civil Protection authorities for emergency management and risk mitigation. The results of InSAR analysis highlighted a general stability of the whole urban area between 1992 and 2007. However, very high deformation rates (up to 10-12 mm/y) were identified in 1992-2000 in the W slope of the town, within the crown and the main scarp area of the Addolorata landslide (occurred in July 1966), and thus was highlighted that the phenomenon was still active. The time-series analysis performed in the NW area of the town, also allowed measuring acceleration (up to 13 mm/y) of the deformation rates near the main Cathedral, starting from August 2006 and persisting until the end of the monitoring period (2007). The new information about the state of activity of these landslides were discussed with the Civil Protection authorities to plan further field investigations and structural surveys to be carried out in the areas at higher risk. The analysis on Agrigento confirmed the capabilities of this integrated approach for detection of ground deformations, long-term monitoring of landslides and, finally, management and mitigation of hydrogeological risk in urban area at local scale.

Cigna, Francesca; Del Ventisette, Chiara; Liguori, Vincenzo; Casagli, Nicola

2010-05-01

322

Guidance on individual monitoring programmes for radioisotopic techniques in molecular and cellular biology.  

PubMed

The radioisotope techniques used in molecular and cellular biology involve external and internal irradiation risk. The personal dosemeter may be a reasonable indicator for external irradiation. However, it is necessary to control the possible internal contamination associated with the development of these techniques. The aim of this project is to analyse the most usual techniques and to establish programmes of internal monitoring for specific radionuclides (32P, 35S, 14C, 3H, 125I and 131I). To elaborate these programmes it was necessary to analyse the radioisotope techniques. Two models have been applied (NRPB and IAEA) to the more significant techniques, according to the physical and chemical nature of the radionuclides, their potential importance in occupational exposure and the possible injury to the genetic material of the cell. The results allowed the identification of the techniques with possible risk of internal contamination. It was necessary to identify groups of workers that require individual monitoring. The risk groups have been established among the professionals exposed, according to different parameters: the general characteristics of receptor, the radionuclides used (the same user can work with one, two or three radionuclides at the same time) and the results of the models applied. Also a control group was established. The study of possible intakes in these groups has been made by urinalysis and whole-body counter. The theoretical results are coherent with the experimental results. They have allowed guidance to individual monitoring to be proposed. Basically, the document shows: (1) the analysis of the radiosotopic techniques, taking into account the special containment equipment; (2) the establishment of the need of individual monitoring; and (3) the required frequency of measurements in a routine programme. PMID:14526986

Macías, M T; Navarro, T; Lavara, A; Robredo, L M; Sierra, I; Lopez, M A

2003-01-01

323

Molecular Predictors of EGFR-TKI Sensitivity in Advanced Non-small Cell Lung Cancer  

PubMed Central

The epidermal growth factor receptor (EGFR) is overexpressed in the majority of non-small cell lung cancers (NSCLC) and is a major target for new therapies. Specific EGFR tyrosine kinase inhibitors (TKIs) have been developed and used for the treatment of advanced NSCLC. The clinical response, however, varies dramatically among different patient cohorts. Females, East Asians, non-smokers, and patients with adenocarcinoma usually show higher response rates. Meanwhile, a number of biological factors are also associated with EGFR-TKIs responsiveness. In order to better understand the predictive value of these biomarkers and their significance in clinical application we prepared this brief review. Here we mainly focused on EGFR somatic mutations, MET amplification, K-ras mutations, EGFRvIII mutation, EGFR gene dosage and expression, HER2 gene dosage and expression, and Akt phosphorylation. We think EGFR somatic mutation probably is the most effective molecular predictor for EGFR-TKIs responsiveness and efficacy. Mutation screening test can provide the most direct and valuable guidance for clinicians to make decision on EGFR-TKIs therapy.

Zhang, Xiaozhu; Chang, Alex

2008-01-01

324

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

2012-10-22

325

Flow Injection Techniques in Aquatic Environmental Analysis: Recent Applications and Technological Advances  

Microsoft Academic Search

This article critically examines the application of flow injection (FI) technology in aquatic environmental analysis. A survey of the important advances in FI technology in the past 5 years (2000–2004) is presented along with critical technological design factors and development issues including automation, preconcentration, speciation, and advanced detection methodologies. Modern environmental applications are also discussed and future perspectives on the

Weihong Xu; Richard C. Sandford; Paul J. Worsfold; Alexandra Carlton; Grady Hanrahan

2005-01-01

326

Development of Techniques to Calibrate and Derive Basic and Advanced Visibility Metrics from Digital Imagery  

Microsoft Academic Search

Images captured with consumer grade digital cameras can be used to estimate visual air quality metrics directly from image pixel data. These indices can be classified as basic and advanced. Basic metrics are calculated using digital image data collected, manipulated, and output by the camera and include sky conditions and target perceptibility. Advanced metrics use the raw or minimally processed

John V Molenar; D. S. Cismoski; Frank Schreiner; William C Malm

327

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

328

The Use of Probabilistic Safety Techniques for Evaluating the Advanced CANDU Reactor (ACR)  

Microsoft Academic Search

THAT WAS SUBMITTED The U.S. Nuclear Regulatory Commission (NRC) is anticipating licensing applications for reactor facilities that are significantly advanced beyond the current generation of operating reactors. One proposed reactor design, developed by Atomic Energy of Canada, Limited (AECL), is an Advanced CANada Deuterium Uranium (CANDU) Reactor (ACR), the ACR-700. The ACR is an enhanced version of earlier CANDU designs.

Michael D. Muhlheim; Donald A. Copinger; Joseph W. Cletcher; A. Linn; Donald L. Williams; John N. Ridgely

329

Review of Advanced Acoustical Imaging Techniques for Nondestructive Evaluation of Art Objects  

Microsoft Academic Search

Proper preventative diagnosis of different art objects, including wooden, bronze and marble sculptures, frescoes, and paintings (on canvas, wood, metal, and glass), is very important for conservation purposes. Various advanced ultrasonic imaging methods for analysis and assessment of art objects can bring about drastic changes in the regular evaluation and inventory carried out by museums and can bring advanced, powerful,

R. G. Maev; R. E. Green Jr; A. M. Siddiolo

2006-01-01

330

An efficient and accurate molecular alignment and docking technique using ab initio quality scoring  

PubMed Central

An accurate and efficient molecular alignment technique is presented based on first principle electronic structure calculations. This new scheme maximizes quantum similarity matrices in the relative orientation of the molecules and uses Fourier transform techniques for two purposes. First, building up the numerical representation of true ab initio electronic densities and their Coulomb potentials is accelerated by the previously described Fourier transform Coulomb method. Second, the Fourier convolution technique is applied for accelerating optimizations in the translational coordinates. In order to avoid any interpolation error, the necessary analytical formulas are derived for the transformation of the ab initio wavefunctions in rotational coordinates. The results of our first implementation for a small test set are analyzed in detail and compared with published results of the literature. A new way of refinement of existing shape based alignments is also proposed by using Fourier convolutions of ab initio or other approximate electron densities. This new alignment technique is generally applicable for overlap, Coulomb, kinetic energy, etc., quantum similarity measures and can be extended to a genuine docking solution with ab initio scoring.

Fusti-Molnar, Laszlo; Merz, Kenneth M.

2008-01-01

331

Enhanced Bio-molecular Sensing Capability of LSPR, SPR-ATR Coupled Technique  

NASA Astrophysics Data System (ADS)

This paper gives a comparative study of two of the SPR techniques i.e. Localised surface plasmon resonance (LSPR) and Surface plasmon resonance-Attenuated total reflection (SPR-ATR) technique and coupling of the two techniques for bio-molecular sensing applications. Silver nanoparticles prepared by using Exploding wire technique and silver thin films prepared by Thermal evaporation were used. Different concentrations of Bovine serum albumin (BSA) were taken for our studies. For LSPR studies, UV-Visible spectrometer was used and a home-made prism coupled ATR-SPR set-up was used for the study of SPR of the thin films. From the comparative studies of our system ATR-SPR method is comparatively a better tool for the optical bio-sensing. Again when bio-molecules tagged with nanoparticles are used, the sensitivity is found to be enhanced abruptly. So the use of both nanoparticles and thin film in the ATR-SPR method gives the best results which could be used as an excellent tool for sensing of bio-molecules and as an effective biosensor.

Singh, N. Kamal; Alqudami, Abdullah; Annapoorni, S.; Sharma, Vineet; Muralidhar, K.

2009-06-01

332

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

333

Sample preparation and in situ hybridization techniques for automated molecular cytogenetic analysis of white blood cells  

SciTech Connect

With the advent in situ hybridization techniques for the analysis of chromosome copy number or structure in interphase cells, the diagnostic and prognostic potential of cytogenetics has been augmented considerably. In theory, the strategies for detection of cytogenetically aberrant cells by in situ hybridization are simple and straightforward. In practice, however, they are fallible, because false classification of hybridization spot number or patterns occurs. When a decision has to be made on molecular cytogenetic normalcy or abnormalcy of a cell sample, the problem of false classification becomes particularly prominent if the fraction of aberrant cells is relatively small. In such mosaic situations, often > 200 cells have to be evaluated to reach a statistical sound figure. The manual enumeration of in situ hybridization spots in many cells in many patient samples is tedious. Assistance in the evaluation process by automation of microscope functions and image analysis techniques is, therefore, strongly indicated. Next to research and development of microscope hardware, camera technology, and image analysis, the optimization of the specimen for the (semi)automated microscopic analysis is essential, since factors such as cell density, thickness, and overlap have dramatic influences on the speed and complexity of the analysis process. Here we describe experiments that have led to a protocol for blood cell specimen that results in microscope preparations that are well suited for automated molecular cytogenetic analysis. 13 refs., 4 figs., 1 tab.

Rijke, F.M. van de; Vrolijk, H.; Sloos, W. [Leiden Univ. (Netherlands)] [and others

1996-06-01

334

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

335

Recent advancements and challenges of palladiumII-catalyzed oxidation reactions with molecular oxygen as the sole oxidant  

PubMed Central

During the past 10 years there have been significant advances in PdII-catalyzed oxidation reactions where the use of ligands has led to the development of catalytic systems capable of achieving high turnover numbers, which employ molecular oxygen as the sole stoichiometric oxidant. This Feature article will highlight some of the recent developments in direct molecular oxygen-coupled PdII-catalyzed oxidation reactions with an emphasis on enhanced catalytic systems and new reactions. Additionally, limitations of current catalytic systems, such as ligand oxidation, are presented and their implications for the development of new reactions are discussed.

Gligorich, Keith M.; Sigman, Matthew S.

2010-01-01

336

Advances in molecular techniques for the detection and quantification of genetically modified organisms  

Microsoft Academic Search

Progress in genetic engineering has led to the introduction of genetically modified organisms (GMOs) whose genomes have been\\u000a altered by the integration of a novel sequence conferring a new trait. To allow consumers an informed choice, many countries\\u000a require food products to be labeled if the GMO content exceeds a certain threshold. Consequently, the development of analytical\\u000a methods for GMO

Dimitrios S. Elenis; Despina P. Kalogianni; Kyriaki Glynou; Penelope C. Ioannou; Theodore K. Christopoulos

2008-01-01

337

Advanced remote sensing techniques for forestry applications: an application case in Sarawak, Malaysia  

NASA Astrophysics Data System (ADS)

12 This paper reports the operational implementation of new techniques for the exploitation of remote sensing data (SAR and optical) in the framework of forestry applications. In particular, we present a new technique for standing timber volume estimation. This technique is based on remote sensing knowledge (SAR and optical synergy) and forestry knowledge (forest structure models), proved fairly accurate. To illustrate the application of these techniques, an operational commercial case study regarding forest concessions in Sarawak is presented. Validation of this technique by comparison of the remote sensing results and the database of the customer has shown that this technique is fairly accurate.

Nezry, Edmond; Yakam-Simen, Francis; Romeijn, Paul P.; Supit, Iwan; Demargne, Louis

2001-02-01

338

Application of Advanced Parameter Identification Methods for Flight Flutter Data Analysis with Comparisons to Current Techniques.  

National Technical Information Service (NTIS)

Grumman has been pursuing the implementation and evaluation of advanced parameter identification software for use in flutter test data processing operations as its Automated Telemetry Station. They have been motivated by aircraft design tending toward thi...

H. J. Perangelo P. R. Waisanen

1984-01-01

339

A Research Project-Based and Self-Determined Teaching System of Molecular Biology Techniques for Undergraduates  

ERIC Educational Resources Information Center

|Molecular biology techniques play a very important role in understanding the biological activity. Students who major in biology should know not only how to perform experiments, but also the reasons for performing them. Having the concept of conducting research by integrating various techniques is especially important. This paper introduces a…

Zhang, Shuping

2008-01-01

340

Mixed chimerism after sex-mismatched allogeneic BMT: evaluation of two molecular techniques.  

PubMed

Two different molecular techniques were used to monitor chimerism following 17 non-T cell-depleted BMTs from female donors to male recipients: pHY10, a Y chromosome-specific probe (Southern or slot blots), and a set of primers for Y chromosome sequence-specific amplification by the polymerase chain reaction (PCR). On Southern blots, male DNA was detectable at a level less than 1% of 10 micrograms DNA while cross-reactivity with autosomal sequences was avoided. On slot blots, male DNA was reliably detectable at levels less than 0.5%, even in small sample (0.5 microgram DNA). With the PCR technique, male DNA was detectable at levels of 1:10(6) to 1:10(7) of 0.5 microgram DNA. Slot blot and PCR results were concordant in 19 of 23 samples. Both techniques demonstrated a constant small mixed chimerism during the first year after BMT and in four of nine patients, this chimerism persisted even longer (up to 29 months after BMT). PMID:8431708

Viard, F; Merel, P; Bilhou-Nabera, C; Marit, G; Comeau, F; Gharbi, M J; Febrer, F; Belloc, F; Lacombe, F; Broustet, A

1993-01-01

341

New technique to determine exciton bandwidths of the lowest exciton band in aromatic molecular crystals  

NASA Astrophysics Data System (ADS)

A new technique to determine the exciton bandwidths of the lowest exciton bands in aromatic molecular crystals has been developed. This technique is based on the fact that in microcrystallites k is not a good quantum number, allowing the optical transition in whole exciton band states. In anthracene microcrystallites, the exciton band width increases with microcrystallite diameter, reaching its maximum value of 340 cm-1. For microcrystallites larger than 65 A in diameter, the observed bandwidth decreases asymptotically to 300 cm-1, which is interpreted to be the bandwidth of bulk crystal. For the above figures 340 cm-1 and 300-1 strong exciton scattering at microcrystallite surfaces is suggested. The same technique is applied to pyrene microcrystallites. The exciton bandwidth for bulk crystal is estimated to be at most 330 cm-1. With the present results, the excitonic state and exciton relaxation processes in pyrene crystals are understood quite successfully. A brief discussion on the exciton bandwidth of the lowest exciton band in coronene is also given.

Matsui, Atsuo H.; Nishi, Osamu; Matsushima, Yoshihiro; Mizuno, Ken-Ichi; Takeshima, Masumi; Oeda, Yoshitaka; Goto, Takenari

1996-03-01

342

Correction of cryptotia with upper auricular deformity: double v-y advancement flap and cartilage strut graft techniques.  

PubMed

Cryptotia is one of the most common auricular anomalies among East Asians and it is frequently associated with upper auricular malformation. Various surgical techniques have been described in the literature, such as V-Y plasty, Z-plasty, skin grafts, local skin flaps, and so on. Although relatively favorable results were obtained by these techniques, some problems remain, such as conspicuous scars, undercorrected or noncorrected auricular cartilage deformities, irregular contour, hair growth, and shallow auriculocephalic sulcus. Because both skin deficiency and cartilage deformities must be corrected for cryptotia with upper auricular deformity, the author has developed new surgical techniques, namely double V-Y advancement flap and cartilage strut graft techniques. These methods provide enough skin to the deformed areas and also good auricular contour with expanded upper auricular portion. PMID:24037381

Kim, Young Soo

2013-10-01

343

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

344

Primary repair of advanced obstetric anal sphincter tears: should it be performed by the overlapping sphincteroplasty technique?  

Microsoft Academic Search

Advanced obstetric anal sphincter tears are often associated with a high incidence of fecal and flatus incontinence. We aimed\\u000a to assess the clinical outcome of these repairs when done by the overlapping sphincteroplasty technique with reconstruction\\u000a of the internal anal sphincter and perineum. Between August 2005 and December 2006, all grades 3 and 4 obstetric anal sphincter\\u000a tears in our

Yoram Abramov; Beni Feiner; Thalma Rosen; Motti Bardichev; Eli Gutterman; Arie Lissak; Ron Auslander

2008-01-01

345

Studies of the nuclear processes of proton capture photon production and spallation neutron emission with advanced experimental techniques  

Microsoft Academic Search

A series of nuclear reaction experiments have been performed in the intermediate energy range up to 1.6 GeV using advanced techniques to detect and measure neutral ejectiles resulting mainly from proton bombardment of both light and heavy nuclei. The proton capture reaction A(p,gamma)A + 1 was studied using a new type of pair spectrometer with large acceptance (PACMAN), which was

Johan Thun

1999-01-01

346

Microscopy Hacks: development of various techniques to assist quantitative nanoanalysis and advanced electron microscopy.  

PubMed

For development of advanced materials, characterization using a scanning transmission electron microscope (STEM) including analysis via X-ray energy-dispersive spectrometry and electron energy-loss spectrometry is essential. Recent advances in aberration-corrected instruments have offered large-scale data acquisition at a high resolution for limited acquisition times both in imaging and in analysis. Further advanced procedures are required to analyze such large-scale datasets more efficiently including quantification. In addition, more simplified tuning procedures are crucial to the best possible resolution in the latest aberration-corrected instruments. In this review article, several approaches to perform advanced electron microscopy, which the author has been developing with his colleague, are described as 'Microscopy Hacks'. These are (i) quantification and elemental/chemical-imaging procedures, (ii) advanced statistical approaches to handle large-scale datasets and (iii) instrument characterization and tuning procedures including the latest development of an ad hoc autotuning procedure for aberration-corrected STEM imaging. PMID:23515525

Watanabe, Masashi

2013-03-20

347

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

348

Synthesis and Bioconjugation of Gold Nanoparticles as Potential Molecular Probes for Light-Based Imaging Techniques  

PubMed Central

We have synthesized and characterized gold nanoparticles (spheres and rods) with optical extinction bands within the “optical imaging window.” The intense plasmon resonant driven absorption and scattering peaks of these nanoparticles make them suitable as contrast agents for optical imaging techniques. Further, we have conjugated these gold nanoparticles to a mouse monoclonal antibody specific to HER2 overexpressing SKBR3 breast carcinoma cells. The bioconjugation protocol uses noncovalent modes of binding based on a combination of electrostatic and hydrophobic interactions of the antibody and the gold surface. We discuss various aspects of the synthesis and bioconjugation protocols and the characterization results of the functionalized nanoparticles. Some proposed applications of these potential molecular probes in the field of biomedical imaging are also discussed.

Rayavarapu, Raja Gopal; Petersen, Wilma; Ungureanu, Constantin; Post, Janine N.; van Leeuwen, Ton G.; Manohar, Srirang

2007-01-01

349

The Application of Molecular Techniques to the Study of Wastewater Treatment Systems  

NASA Astrophysics Data System (ADS)

Wastewater treatment systems tend to be engineered to select for a few functional microbial groups that may be organized in various spatial structures such as activated sludge flocs, biofilm or granules and represented by single coherent phylogenic groups such as ammonia-oxidizing bacteria (AOB) and polyphosphate-accumulating organisms (PAO). In order to monitor and control engineered microbial structure in wastewater treatment systems, it is necessary to understand the relationships between the microbial community structure and the process performance. This review focuses on bacterial communities in wastewater treatment processes, the quantity of microorganisms and structure of microbial consortia in wastewater treatment bioreactors. The review shows that the application of molecular techniques in studies of engineered environmental systems has increased our insight into the vast diversity and interaction of microorganisms present in wastewater treatment systems.

Wojnowska-Bary?a, Irena; Cydzik-Kwiatkowska, Agnieszka; Zieli?ska, Magdalena

350

Generalized-ensemble algorithms: enhanced sampling techniques for Monte Carlo and molecular dynamics simulations.  

PubMed

In complex systems with many degrees of freedom such as spin glass and biomolecular systems, conventional simulations in canonical ensemble suffer from the quasi-ergodicity problem. A simulation in generalized ensemble performs a random walk in potential energy space and overcomes this difficulty. From only one simulation run, one can obtain canonical ensemble averages of physical quantities as functions of temperature by the single-histogram and/or multiple-histogram reweighting techniques. In this article we review the generalized ensemble algorithms. Three well-known methods, namely, multicanonical algorithm (MUCA), simulated tempering (ST), and replica-exchange method (REM), are described first. Both Monte Carlo (MC) and molecular dynamics (MD) versions of the algorithms are given. We then present five new generalized-ensemble algorithms which are extensions of the above methods. PMID:15099838

Okamoto, Yuko

2004-05-01

351

Operation mechanism of rotary molecular motor F1 probed by single-molecule techniques  

NASA Astrophysics Data System (ADS)

F1 is a rotary motor protein. Three catalytic ?-subunits in the stator ?3?3 ring are torque generators, and rotate the rotor ?-subunit by sequential and cooperative conformational changes coupled with adenosine triphosphate (ATP) hydrolysis reaction. F1 shows remarkable performances such as rotation rate faster than 10,000 rpm, high reversibility and efficiency in chemo-mechanical energy conversion. I will introduce basic characteristics of F1 revealed by single-molecule imaging and manipulation techniques based on optical microscopy and high-speed atomic force microscopy. I will also discuss the possible operation mechanism behind the F1, along with structurally-related hexameric ATPases, also mentioning the possibility of generating hybrid molecular motors.

Iino, Ryota

2013-03-01

352

A study on the molecular interaction of PPG 3000 and its blend using ultrasonic technique  

NASA Astrophysics Data System (ADS)

Ultrasonic study has become an important research tool in the field of polymers for investigating the structure and molecular interactions in multi component system. Ultrasonic studies were carried out on Polypropylene glycol [PPG 3000] at different concentrations [0-1%] in toluene at 303K. Various parameters like adiabatic compressibility, free volume and internal pressure were calculated. The ultrasonic velocity increases with increase in the concentration. An attempt has been made to blend Polypropylene glycol [PPG] 400 with PPG 3000 at 303K at various compositions and the miscibility nature of the blend is analyzed through ultrasonic study. The variation of ultrasonic velocity with blend composition is nonlinear and follows S-type pattern, which shows that the blend is immiscible. The miscibility nature of the blend is further confirmed through other techniques like viscosity and optical studies.

Venkatramanan, K.; Padmanaban, R.; Arumugam, V.

2012-05-01

353

Comparative study of four advanced 3d-conformal radiation therapy treatment planning techniques for head and neck cancer  

PubMed Central

For the head-and-neck cancer bilateral irradiation, intensity-modulated radiation therapy (IMRT) is the most reported technique as it enables both target dose coverage and organ-at-risk (OAR) sparing. However, during the last 20 years, three-dimensional conformal radiotherapy (3DCRT) techniques have been introduced, which are tailored to improve the classic shrinking field technique, as regards both planning target volume (PTV) dose conformality and sparing of OAR’s, such as parotid glands and spinal cord. In this study, we tested experimentally in a sample of 13 patients, four of these advanced 3DCRT techniques, all using photon beams only and a unique isocentre, namely Bellinzona, Forward-Planned Multisegments (FPMS), ConPas, and field-in-field (FIF) techniques. Statistical analysis of the main dosimetric parameters of PTV and OAR’s DVH’s as well as of homogeneity and conformity indexes was carried out in order to compare the performance of each technique. The results show that the PTV dose coverage is adequate for all the techniques, with the FPMS techniques providing the highest value for D95%; on the other hand, the best sparing of parotid glands is achieved using the FIF and ConPas techniques, with a mean dose of 26 Gy to parotid glands for a PTV prescription dose of 54 Gy. After taking into account both PTV coverage and parotid sparing, the best global performance was achieved by the FIF technique with results comparable to that of IMRT plans. This technique can be proposed as a valid alternative when IMRT equipment is not available or patient is not suitable for IMRT treatment.

Herrassi, Mohamed Yassine; Bentayeb, Farida; Malisan, Maria Rosa

2013-01-01

354

Sex determination of Pohnpei Micronesian kingfishers using morphological and molecular genetic techniques  

USGS Publications Warehouse

Conservation-oriented studies of Micronesian Kingfishers (Todiramphus cinnamominus) have been hindered by a lack of basic natural history information, despite the status of the Guam subspecies (T. c. cinnamominus) as one of the most endangered species in the world. We used tissue samples and morphometric measures from museum specimens and wild-captured Pohnpei Micronesian Kingfishers (T. c. reichenbachii) to develop methods for sex determination. We present a modified molecular protocol and a discriminant function that yields the probability that a particular individual is male or female. Our results revealed that females were significantly larger than males, and the discriminant function correctly predicted sex in 73% (30/41) of the individuals. The sex of 86% (18/21) of individuals was correctly assigned when a moderate reliability threshold was set. Sex determination using molecular genetic techniques was more reliable than methods based on morphology. Our results will facilitate recovery efforts for the critically endangered Guam Micronesian Kingfisher and provide a basis for sex determination in the 11 other endangered congeners in the Pacific Basin.

Kesler, Dylan C.; Lopes, I. F.; Haig, Susan M.

2006-01-01

355

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

356

First prokaryotic biodiversity assessment using molecular techniques of an acidic river in Neuquén, Argentina.  

PubMed

Two acidic hot springs close to the crater of Copahue Volcano (Neuquén, Argentina) are the source of the Río Agrio. The river runs several kilometres before flowing into Caviahue Lake. Along the river, temperature, iron, other metal and proton concentrations decrease gradually with distance downstream. From the source to the lake and depending on the season, pH can rise from 1.0 (or even less) to about 4.0, while temperature values decrease from 70°C to 15°C. Water samples were taken from different stations on the river selected according to their physicochemical parameters. In order to assess prokaryotic biodiversity throughout the water column, different and complementary molecular biology techniques were used, mainly in situ hybridisation and 16S rRNA gene cloning and sequencing. All microorganisms found are typical of acidic environments. Sulphur-oxidizing bacteria like Acidithiobacillus thiooxidans and Acidithiobacillus albertensis were detected in every station. Moderately thermophile iron- and sulphur-oxidizing bacteria like members of Alicyclobacillus and Sulfobacillus genera were also ubiquitous. Strict iron-oxidizing bacteria like Leptospirillum and Ferrimicrobium were present at the source of the river, but disappeared downstream where iron concentrations were much lower. Iron-oxidizing, mesophilic Ferroplasma spp. were the main archaea found. The data presented in this work represent the first molecular assessment of this rare natural acidic environment. PMID:22214994

Urbieta, M Sofía; González Toril, E; Aguilera, A; Giaveno, M Alejandra; Donati, E

2012-01-04

357

Persistence of Bacteroides species populations in a river as measured by molecular and culture techniques.  

PubMed

Given the interest in Bacteroides species as microbial source tracking (MST) markers, and the limited knowledge of the survival of Bacteroides species in the environment, here we examine the survival of Bacteroides fragilis, B. thetaiotaomicron, and environmental species of Bacteroides by use of culture techniques and molecular tools. Two kinds of experiments were performed: (i) on-site experiments, in which bacteria were exposed to changes in the levels of several environmental parameters in a river, and (ii) microcosm assays in the laboratory, with controlled temperatures. On-site experiments showed different survival patterns for the cultivable Bacteroides strains. B. fragilis die-off rate was strongly affected by the combined effect of high temperatures and grazing predators, which were more active under warmer conditions. However, the survival rates of cultivable B. thetaiotaomicron and environmental Bacteroides spp. were more affected by dissolved oxygen (DO) concentration in water. Environmental Bacteroides strains survived longer than either type strain, due to better adaptation to environmental conditions. However, the period of their survival was shorter than that observed for fecal coliforms and enterococci, suggesting Bacteroides species as markers of recent fecal pollution. The total Bacteroides species were detected by molecular techniques throughout the experiment in winter, but they were detected on only two or three days in the summer. This indicates that temperature is the main factor affecting DNA degradation, regardless of species. The use of microcosms in the laboratory also pointed to temperature as the main factor affecting Bacteroides survival, regardless of species. However, the conditions in the laboratory may mask the effects of the environmental factors and their interactions. The observed variability in die-off rate as a function of the species analyzed, the experimental conditions, and the methodology used should be taken into consideration in future persistence studies. PMID:20851970

Ballesté, Elisenda; Blanch, Anicet R

2010-09-17

358

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

PubMed

An effusive molecular beam technique is described to measure alkane dissociative sticking coefficients, S(T(g), T(s); ?), on metal surfaces for which the impinging gas temperature, T(g), and surface temperature, T(s), can be independently varied, along with the angle of incidence, ?, of the impinging gas. Effusive beam experiments with T(g) = T(s) = 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(T(g), T(s); ?) measurements for which T(g) ? T(s) 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 T(g) 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). PMID:21529024

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

2011-04-01

359

Preoperative therapy for advanced pelvic malignancy by isolated pelvic perfusion with the balloon-occlusion technique  

Microsoft Academic Search

Background: Although the technique of isolated pelvic perfusion dates back to the time of Creech (1959) and has been used by a variety\\u000a of authors to treat unresectable neoplasms, the inherent complexity of the open procedure limited its widespread use. We simplified\\u000a the technique through use of the balloon-occlusion technique for aortic and caval control. Our initial efforts used this

Harold J. Wanebo; Maureen A. Chung; Audrey I. Levy; Peter S. Turk; Michael P. Vezeridis; James F. Belliveau

1996-01-01

360

Advanced technique in liquid scintillation counting to compute radionuclide activity using full energy spectrum analysis  

Microsoft Academic Search

Liquid scintillation research in the area of characterizing the pulse-height energy distribution spectra of different beta particle and gamma-ray emitting radionuclides has resulted in a new technique developed to compute dual-label radionuclide activity (dpm). Improved statistical precision and enhanced radionuclide separations for dual-labeled measurements are significant attributes of this technique. A liquid scintillation counting technique to computer radionuclide activity using

De Filippis

1985-01-01

361

An Advanced Optimization Technique for Layer-Specific Characterization of Slab Metamaterials  

NASA Astrophysics Data System (ADS)

A new optimization technique for evaluating the complex effective relative permittivity and permeability of elementary sub-slab whose thickness equals to the constant of a unit cell of a slab metamaterial is developed. The objective of the technique is based on a numerical solving of appropriate minimization problem for a cascaded network representation of the slab metamaterial utilizing the Effective Medium Theory (EMT) and the definition of S- and T-parameters of the metamaterials considered as a four-pole network. The technique is tested using the open source FDTD software package and the optimization technique obtained [O. Rybin and M. Raza, Int. J. Appl. Electrom. Mech.32, 207 (2010)].

Rybin, Oleg

2013-04-01

362

Advanced microtomography combined synchrotron x-ray diffraction techniques for phase transformation researches in amorphous materials under pressure  

NASA Astrophysics Data System (ADS)

Advanced tomographic and x-ray diffraction techniques have attracted more attentions in mineral physics community in these years. In a recent collaborative project in APS of Argonne National Laboratory, we discovered unexpected dynamics and volume expansion associated with pressure-induced crystallization of amorphous Se by using novel high-pressure diamond anvil cell microtomography and x-ray diffraction techniques. The unusual volume expansion phenomenon under pressure associated with the recrystallization of over-pressurization of a metastable phase was found, which may be more common than previously believed. Tuning relative densities and energetics of phases under pressure may provide a new route for creating new structures from highly metastable states. The new microtomographic technique could find widespread use in determinations of the equation of state of glasses and melts under pressures, which is crucial to many problems in earth sciences. The importance of using advanced time-resolved or spatially-resolved high-pressure x-ray diffraction and imaging techniques will be emphasized. This will improve our understanding of the kinetics of structural transformations in minerals under extreme conditions far from equilibrium.

Wang, L.; Liu, H.

2009-12-01

363

Three Case Reports of the Metabolic and Electroencephalographic Changes during Advanced Buddhist Meditation Techniques  

Microsoft Academic Search

To examine the extent to which advanced meditative practices might alter body metabolism and the electroencephalogram (EEG), we investigated three Tibetan Buddhist monks living in the Rumtek monastery in Sikkim, India. In a study carried out in February 1988, we found that during the practice of several different meditative practices, resting metabolism ([Vdot]O2) could be both raised (up to 61%)

Herbert Benson; M. S. Malhotra; Ralph F. Goldman; Gregg D. Jacobs; P. Jeffrey Hopkins

1990-01-01

364

Recent Developments of Aircraft Nondestructive Evaluation Based on Advanced Sensor Techniques  

Microsoft Academic Search

The safety and structural integrity are of great importa nce to military and commercial aircraft, and the developments of effective nondestruct ive evaluation (NDE) methods are receiving much attention in recent years. The objective o f this paper was to provide the recent developments of aircraft NDE based on advanced sensor t echniques: (a) Ultrasonic testing with piezoceramic sensor arrays,

Gongjin QI; Hong LEI; Rongsheng GENG; Peng JING

365

Advanced Liquid Waste Treatment System Using a High Efficiency Solidification Technique.  

National Technical Information Service (NTIS)

An advanced system using High Efficiency Solidification Technology (HEST) was developed to treat PWR liquid waste and the first unit is operating in Taiwan (1) and a detailed design is being carried out for the second unit in Japan. The HEST system consis...

M. Kikuchi S. Hirayama

2003-01-01

366

The ? f–? R QCM technique: an approach to an advanced sensor signal interpretation  

Microsoft Academic Search

The frequency shift and the resistance change of a quartz crystal microbalance (QCM) coated with a viscoelastic film and working in a viscous liquid are analysed. It is shown that the measurement of the resistance provides additional information for an advanced signal interpretation. With the measurement of both values, viscoelastic contributions to the frequency response can be discovered. We present

Ralf Lucklum; Peter Hauptmann

2000-01-01

367

Thermal management techniques for an advanced linear motor in an electric aircraft recovery system  

Microsoft Academic Search

A study was conducted to quantify the thermal characteristics and to determine alternative methods to maintain thermal equilibrium for an advanced linear motor (ALM). The ALM is an essential component in the design and development of the next generation aircraft launch and recovery systems. The development of a thermal management system for the ALM is critical for maximizing the benefits

Ryan J. Elwell; Richard W. Garman; Micheal Doyle

2001-01-01

368

Advanced technique for interfacial tension measurement in liquid-liquid systems.  

National Technical Information Service (NTIS)

A technique for determining interfacial tension from the shape of an axisymmetric fluid-liquid interface is presented. The technique entails using a novel data acquisition method which uses a high speed video camera to record pendant drop images and a sta...

M. T. Harris C. H. Byers

1989-01-01

369

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

370

Recent Advances in SolidPhase Microextraction and Related Techniques for Pharmaceutical and Biomedical Analysis  

Microsoft Academic Search

Sample preparation is essential for isolating desired components from complex matrices and greatly influences their reliable and accurate analysis. Solid-phase microextraction (SPME) is a new and effective sample preparation technique. Fibers and capillary tubes coated with an appropriate stationary phase are usually used for SPME, but alternative microextraction techniques, including solid-phase dynamic extraction using an internal coated needle, microextraction in

Hiroyuki Kataoka

2005-01-01

371

Recent advances in feature extraction techniques being developed for ultrasonic examination of austenitic stainless steel welds  

Microsoft Academic Search

Techniques are described which are being developed to characterize the features found during ultrasonic examination of stainless steel welds which are indicative of defects. Ultrasonic waveforms obtained from both defects and grain boundaries have similar time-domain characteristics. This phenomenon, together with variable signal attenuation and dispersion, is commonly encountered. The problem is to develop feature extraction techniques which will enable

S. J. Mech; J. S. Emmons; T. E. Michaels

1978-01-01

372

ADVANCED MAINTENANCE AND REPAIR FOR OFFSHORE WIND FARMS USING FAULT PREDICTION TECHNIQUES  

Microsoft Academic Search

Fault prediction and condition monitoring techniques are used in many fields of electrical energy generation, e.g. in rotating components of power plant generators or cooling pumps. Most of this techniques are transferable for use in wind energy converters. For many years, ISET has been working in the field of condition monitoring and fault prediction in wind energy converters and has

P. Caselitz; J. Giebhardt

373

A comparison of advanced distillation control techniques for a propylene/propane splitter  

SciTech Connect

A detailed dynamic simulator of a propylene/propane (C{sub 3}) splitter, which was bench-marked against industrial data, has been used to compare dual composition control performance for a diagonal PI controller and several advanced controllers. The advanced controllers considered are DMC, nonlinear process model based control, and artificial neural networks. Each controller was tuned based upon setpoint changes in the overhead production composition using 50% changes in the impurity levels. Overall, there was not a great deal of difference in controller performance based upon the setpoint and disturbance tests. Periodic step changes in feed composition were also used to compare controller performance. In this case, oscillatory variations of the product composition were observed and the variabilities of the DMC and nonlinear process model based controllers were substantially smaller than that of the PI controller. The sensitivity of each controller to the frequency of the periodic step changes in feed composition was also investigated.

Gokhale, V.; Hurowitz, S.; Riggs, J.B. [Texas Tech Univ., Lubbock, TX (United States). Dept. of Chemical Engineering

1995-12-01

374

Three case reports of the metabolic and electroencephalographic changes during advanced Buddhist meditation techniques.  

PubMed

To examine the extent to which advanced meditative practices might alter body metabolism and the electroencephalogram (EEG), we investigated three Tibetan Buddhist monks living in the Rumtek monastery in Sikkim, India. In a study carried out in February 1988, we found that during the practice of several different meditative practices, resting metabolism (VO2) could be both raised (up to 61%) and lowered (down to 64%). The reduction from rest is the largest ever reported. On the EEG, marked asymmetry in alpha and beta activity between the hemispheres and increased beta activity were present. From these three case reports, we conclude that advanced meditative practices may yield different alterations in metabolism (there are also forms of meditation that increase metabolism) and that the decreases in metabolism can be striking. PMID:2194593

Benson, H; Malhotra, M S; Goldman, R F; Jacobs, G D; Hopkins, P J

1990-01-01

375

Advances in fiber-optic based UV resonance Raman spectroscopy techniques for anatomical and physiological investigations  

Microsoft Academic Search

Ultraviolet resonance Raman spectroscopy (UVRRS) is becoming a very popular spectroscopic method for bioanalytical investigations due to its high sensitivity, lack of fluorescence, and suitability for use in aqueous solutions. We have made a number of technological advances, especially the development of fiber-optic-b ased technologies, which permit the performance of remote\\/in-sit u UVRRS measurements. We will be reporting on improved

H. Georg Schulze; Christopher J. Barbosa; L. Shane Greek; Robin F. B. Turner; Charles A. Haynes; Michael W. Blades

376

Surgery of Residual Disease Following Molecular-targeted Therapy With Imatinib Mesylate in Advanced/Metastatic GIST  

PubMed Central

Objective: To explore the role of surgery of residual disease following a period of therapy with imatinib mesylate in advanced gastrointestinal stromal tumors (GIST). Methods: From January 2001 to June 2005, 159 patients with advanced/metastatic GIST were treated with imatinib mesylate at a single institution. As of June 2002, 38 patients were selected for surgery following a variable period of imatinib therapy. Twenty-seven patients were operated on while they were in response, 8 in progression, 3 for localized disease. Clinical, pathologic, and molecular features were assessed and are reported. Results: Postsurgery PFS was 96% at 12 months and 69% at 24 months for responding patients, while it was nil at 12 months for progressing ones. Disease-specific survival at 12 months was 100% for responding patients and 60% for progressing ones. In responding cases, secondary progression was mainly related to postsurgical imatinib discontinuation, irrespective of pathologic or molecular variables. In progressing patients, secondary resistance was mainly related to acquired mutations. Conclusion: In advanced GIST patients who are responding to imatinib mesylate, the role of surgery is not formally demonstrated at the moment, but this option may well be considered investigational, or suitable for an individualized decision-making in the lack of evidence. In our series, patients progressing on imatinib mesylate did not seem to have any major benefit from surgery, although their number is low.

Gronchi, Alessandro; Fiore, Marco; Miselli, Francesca; Lagonigro, Maria Stefania; Coco, Paola; Messina, Antonella; Pilotti, Silvana; Casali, Paolo Giovanni

2007-01-01

377

Development of Laser Spectroscopic Diagnostics to Support Advanced Compound Semiconductor Deposition Techniques.  

National Technical Information Service (NTIS)

This program constructed and demonstrated an apparatus for the development of laser diagnostics for the gas phase molecules involved in semiconductor fabrication techniques, particularly the organometallic chemical vapor deposition of compound semiconduct...

J. C. Wormhoudt

1990-01-01

378

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.

2008-01-01

379

Recent Advances in Feature Extraction Techniques Being Developed for Ultrasonic Examination of Austenitic Stainless Steel Welds.  

National Technical Information Service (NTIS)

Techniques are described which are being developed to characterize the features found during ultrasonic examination of stainless steel welds which are indicative of defects. Ultrasonic waveforms obtained from both defects and grain boundaries have similar...

S. J. Mech J. S. Emmons T. E. Michaels

1978-01-01

380

The Advanced Electric Power Grid: Complexity Reduction Techniques for Reliability Modeling  

Microsoft Academic Search

The power grid is a large system, and analyzing its reliability is computationally intensive, rendering conventional methods\\u000a ineffective. This paper proposes techniques for reducing the complexity of representations of the grid, resulting in a mathematically\\u000a tractable problem to which our previously developed reliability analysis techniques can be applied. The IEEE118 bus system\\u000a is analyzed as an example, incorporating cascading failure

Ayman Z. Faza; Sahra Sedigh; Bruce M. Mcmillin

2008-01-01

381

[National survey of the infrastructure of research centers in advanced biotechnology and molecular epidemiology in Mexico].  

PubMed

An International Molecular Epidemiology Task Force group (IMETAF) was established in 1993, where the Mexican group include as their objectives: the evaluation of the main public health problems that could be improvement through molecular epidemiology; the analysis of the interaction between molecular biology and epidemiology; development of international nets of collaboration and the establishment of surveys toward the prevention and control of some diseases. As part of a general strategy the Mexican scientific committee developed the first national infrastructure survey of the centers of biotechnology and molecular epidemiology. This survey obtained data trough a questionnaire of the general characteristics the development of the molecular epidemiology, the main tools of surveys, equipment, material and reagents, the personnel trained in biotechnology, epidemiology and public health, the needs of training, the national and international nets, how to develop molecular epidemiology and areas to be considered. The results give a general idea of the possibilities to develop the field in Mexico. More than 50% are currently working in this theme. The majority in infectious diseases. The centers have the equipment, material reagents and human resources well trained to incorporate the molecular epidemiology in their usual work. They reported the need of technology transfer to develop collaborations and courses, symposia or congresses. We conclude that Mexico has the capability and the infrastructure to develop molecular epidemiology. A survey is needed on animals. PMID:9504100

Sartí, E; Orozco, S; Dorman, J; Tapia, R; Gorodezky, C

1997-01-01

382

Emerging optical techniques in advanced cystoscopy for bladder cancer diagnosis: A review of the current literature  

PubMed Central

Background and objective: The current standard for the diagnosis and followup of bladder cancer remains white light cystoscopy, despite its well-known limitations. The aim of this paper is to review the current literature on three optical diagnostics that have been developed to improve the performance of white light cystoscopy: photodynamic diagnosis, narrow-band imaging and optical coherence tomography. Materials and Methods: A PubMed search was performed for all articles on bladder cancer and photodynamic diagnosis, narrow-band imaging, and optical coherence tomography. Relevant papers on the working mechanism or clinical performance of the techniques were selected. Results: Photodynamic diagnosis and narrow-band imaging both aim to improve the visualization of bladder cancer. Both techniques have demonstrated an improved detection rate of bladder cancer. For photodynamic diagnosis, decreased residual tumor rates and increased recurrence free survival after photodynamic diagnosis-assisted transurethral resection have been shown. Both techniques have a relatively high false positive rate. Optical coherence tomography is a technique aiming at real-time noninvasive pathological diagnosis. Studies have shown that optical coherence tomography can accurately discriminate bladder cancer from normal bladder mucosa, and even suggest that a reliable estimation of the stage of a bladder tumor can be made. Conclusions: Photodynamic diagnosis is the technique with most evidence of clinical effectiveness to date, but low specificity is limiting a widespread use. For the novelties, narrow-band imaging, and optical coherence tomography, more evidence is needed before these techniques can be implemented in daily urological practice.

Cauberg Evelyne, C.C.; de la Rosette, Jean J.M.C.H.; de Reijke, Theo M.

2011-01-01

383

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

Microsoft Academic Search

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

Janet Oliver; Janet Pfeiffer; Bridget Wilson; Alan Richard Burns

2006-01-01

384

Molecular Engineering of Vector-Based Oncolytic and Imaging Approaches for Advanced Prostate Cancer.  

National Technical Information Service (NTIS)

Hormone refractory and metastatic prostate cancer are not well understood. Better animal models, diagnostic and treatment modalities are sorely needed for these advanced stages of disease. We have developed metastatic prostate cancer animal models that ca...

L. Wu

2007-01-01

385

Development of Experimental Techniques Using LVP (Large Volume Press) at GSECARS Beamlines, Advanced Photon Source (in Japanese with English abstract)  

SciTech Connect

GSECARS (GeoSoilEnviroCARS, the University of Chicago) operates a bending magnet and an undulator beamlines at Sector 13, Advanced Photon Source. Experimental technique for High Pressure X-ray Tomographic Microscope (HPXTM) using monochromatized X-rays has been developed. The module for HPXTM also has shear deformation capability, which enables us to perform HPXTM experiments for microstructure developed by shear deformation under high pressure. A combination of Deformation DIA (D-DIA) and monochromatic X-rays has been developed for quantitative deformation experiments under pressure above 10 GPa. Deformation experiments of e-iron was performed at pressures up to 19 GPa and temperatures up to 700 K.

Nishiyama, N.; Wang, Y. (Ehime U)

2009-09-09

386

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

387

Adaptive optics with advanced phase-contrast techniques. II. High-resolution wave-front control.  

PubMed

A wave-front control paradigm based on gradient-flow optimization is analyzed. In adaptive systems with gradient-flow dynamics, the output of the wave-front sensor is used to directly control high-resolution wavefront correctors without the need for wave-front phase reconstruction (direct-control systems). Here, adaptive direct-control systems with advanced phase-contrast wave-front sensors are analyzed theoretically, through numerical simulations, and experimentally. Adaptive system performance is studied for atmospheric-turbulence-induced phase distortions in the presence of input field intensity scintillations. The results demonstrate the effectiveness of this approach for high-resolution adaptive optics. PMID:11393623

Justh, E W; Vorontsov, M A; Carhart, G W; Beresnev, L A; Krishnaprasad, P S

2001-06-01

388

Advanced computer techniques for inverse modeling of electric current in cardiac tissue  

SciTech Connect

For many years, ECG`s and vector cardiograms have been the tools of choice for non-invasive diagnosis of cardiac conduction problems, such as found in reentrant tachycardia or Wolff-Parkinson-White (WPW) syndrome. Through skillful analysis of these skin-surface measurements of cardiac generated electric currents, a physician can deduce the general location of heart conduction irregularities. Using a combination of high-fidelity geometry modeling, advanced mathematical algorithms and massively parallel computing, Sandia`s approach would provide much more accurate information and thus allow the physician to pinpoint the source of an arrhythmia or abnormal conduction pathway.

Hutchinson, S.A.; Romero, L.A.; Diegert, C.F.

1996-08-01

389

Evaluation of molecular techniques for identification and enumeration of Raoultella terrigena ATCC 33257 in water purifier efficacy testing  

Microsoft Academic Search

Raoultella terrigena ATCC 33257, a representative of the coliform group, is commonly used as a challenge organism in water purifier efficacy testing.\\u000a In addition to being time consuming, traditional culturing techniques and metabolic identification systems (including automated\\u000a systems) also fail to accurately differentiate this organism from its closely related neighbors belonging to the Enterobacteriaceae\\u000a group. Molecular-based techniques, such as real-time

Ratul Saha; Robin Bechanko; Lorelle L. Bestervelt; Robert S. Donofrio

390

Fault Detection of Gearbox from Inverter Signals Using Advanced Signal Processing Techniques  

NASA Astrophysics Data System (ADS)

The gear faults are time-localized transient events so time-frequency analysis techniques (such as the Short-Time Fourier Transform, Wavelet Transform, motor current signature analysis) are widely used to deal with non-stationary and nonlinear signals. Newly developed signal processing techniques (such as empirical mode decomposition and Teager Kaiser Energy Operator) enabled the recognition of the vibration modes that coexist in the system, and to have a better understanding of the nature of the fault information contained in the vibration signal. However these methods require a lot of computational power so this paper presents a novel approach of gearbox fault detection using the inverter signals to monitor the load, rather than the motor current. The proposed technique could be used for continuous monitoring as well as on-line damage detection systems for gearbox maintenance.

Pislaru, C.; Lane, M.; Ball, A. D.; Gu, F.

2012-05-01

391

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

392

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

393

Association of immunohistochemically defined molecular subtypes with clinical response to presurgical chemotherapy in patients with advanced breast cancer.  

PubMed

Gene expression profiling (GEP) has identified several molecular subtypes of breast cancer, with different clinico-pathologic features and exhibiting different responses to chemotherapy. However, GEP is expensive and not available in the developing countries where the majority of patients present at advanced stage. The St Gallen Consensus in 2011 proposed use of a simplified, four immunohistochemical (IHC) biomarker panel (ER, PR, HER2, Ki67/Tumor Grade) for molecular classification. The present study was conducted in 75 newly diagnosed patients of breast cancer with large (>5cm) tumors to evaluate the association of IHC surrogate molecular subtype with the clinical response to presurgical chemotherapy, evaluated by the WHO criteria, 3 weeks after the third cycle of 5 flourouracil, adriamycin, cyclophosphamide (FAC regimen). The subtypes of luminal, basal-like and HER2 enriched were found to account for 36.0 % (27/75), 34.7 % (26/75) and 29.3% (22/75) of patients respectively. Ten were luminal A and 14 luminal B (8 HER2 negative and 6HER2 positive). The triple negative breast cancer (TNBC) was most sensitive to chemotherapy with 19% achieving clinical-complete-response (cCR) followed by HER2 enriched (2/22 (9%) cCR), luminal B (1/6 (7%) cCR) and luminal A (0/10 (0%) cCR). Heterogeneity was observed within each subgroup, being most marked in the TNBC although the most responding tumors, 8% developing clinical-progressive-disease. The study supports association of molecular subtypes with response to chemotherapy in patients with advanced breast cancer and the existence of further heterogeneity within subtypes. PMID:23803108

Khokher, Samina; Qureshi, Muhammad Usman; Mahmood, Saqib; Nagi, Abdul Hannan

2013-01-01

394

Applications of Advanced Experimental Methods to Visual Technology Research Simulator Studies: Supplemental Techniques.  

National Technical Information Service (NTIS)

This report is made up of a series of individual papers on techniques to enhance the behavioral research methods being used in the VTRS, or Visual Technology Research Simulator (formerly referred to as AWAVS, or Aviation Wide-Angle Visual System). These m...

C. W. Simon

1981-01-01

395

Thin-layer chromatography, overlay technique and mass spectrometry: A versatile triad advancing glycosphingolipidomics  

Microsoft Academic Search

Much effort is currently invested in the development of mass spectrometry-based strategies for investigating the entirety of glycosphingolipids (GSLs) of a certain cell type, tissue, organ or body encompassing the respective glycosphingolipidome. As part of the investigation of the vertebrate glycosphingolipidome, GSL analysis is undergoing rapid expansion owing to the application of novel mass spectrometry techniques acting as the linchpin

Iris Meisen; Michael Mormann; Johannes Müthing

2011-01-01

396

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

397

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

398

Development of laser spectroscopic diagnostics to support advanced compound semiconductor deposition techniques  

Microsoft Academic Search

This program constructed and demonstrated an apparatus for the development of laser diagnostics for the gas phase molecules involved in semiconductor fabrication techniques, particularly the organometallic chemical vapor deposition of compound semiconductors like gallium arsenide. Work on this apparatus, a flow tube with mirrors for long path tunable infrared diode laser absorption and electrodes for a radio frequency glow discharge,

Joda C. Wormhoudt

1990-01-01

399

An alternative suspension technique after trapeziectomy for advanced thumb carpometacarpal osteoarthritis.  

PubMed

Osteoarthritis of the first carpometacarpal joint is often treated by (partial) trapeziectomy and tendon interposition or suspension arthroplasty procedures. In this article, an alternative suspension technique, using 2 osseous tunnels (through the first and second metacarpal) and a flexor carpi radialis tendon strip, is described. PMID:22913992

Spaans, Anne J; van Laarhoven, Cecile M C M; van Minnen, L Paul; Schuurman, Arnold H

2012-09-01

400

Recent Advance of Hydride Generation-Analytical Atomic Spectrometry: Part I-Technique Development  

Microsoft Academic Search

Hydride generation is the most popular and widely used chemical vapor generation, which is always interesting to analytical chemists as an effective sample introduction method, especially for elemental determination and speciation analysis by analytical atomic spectrometry. The present review provides a literature survey on the hydride generation technique coupled to analytical atomic spectrometry during the past several years, covering the

Zhou Long; Yamin Luo; Chengbin Zheng; Pengchi Deng; Xiandeng Hou

2012-01-01

401

Review on Process-Induced Strain Techniques for Advanced Logic Technologies  

Microsoft Academic Search

We have extensively studied stress enhancing techniques to increase channel mobility starting at the 130 nm technology node and continued this towards the 45 nm node. Stressed overlayers and spacer materials, strained SOI substrates, embedded SiGe and SiC layers and their proximity effects, the impact of different silicides, stress memorization and compatibility with laser and flash anneals have been investigated.

M. Wiatr; T. Feudel; A. Wei; A. Mowry; R. Boschke; P. Javorka; A. Gehring; T. Kammler; M. Lenski; K. Frohberg; R. Richter; M. Horstmann; D. Greenlaw

2007-01-01

402

Advanced Techniques for Personalized Advertising in a Digital TV Environment: The iMEDIA System  

Microsoft Academic Search

This paper presents the innovative approach of the IST project iMEDIA towards Consumer Clustering and Targeted Advertising in a Digital TV Environment. iMEDIA covers the need of Advertising Companies to identify broad classes of TV viewers who will respond similarly to marketing actions, and thus develop their target advertising techniques. The consumers are equipped with a set- top box (STB)

Theodoros Bozios; Georgios Lekakos; Victoria Skoularidou

403

Advanced screen printing technique for high definition front side metallization of crystalline silicon solar cells  

Microsoft Academic Search

This work presents a new, readily implementable screen printing technique for the front side metallization of textured mono- and multi-crystalline silicon solar cells. The use of a heated print chuck to increase the substrate temperature during the screen print process enables a significantly reduced printed line width for conventional and fine line screen printing. The influence of substrate temperature on

Denis Erath; Aleksander Filipovi?; Marc Retzlaff; Anne Kathrin Goetz; Florian Clement; Daniel Biro; Ralf Preu

2010-01-01

404

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

405

The molecular gas content of the advanced S+E merger NGC 4441. Evidence for an extended decoupled nuclear disc?  

NASA Astrophysics Data System (ADS)

Context. Despite their importance to galaxy evolution, mergers between a spiral and an elliptical (S+E mergers) have been poorly studied so far. NGC 4441 is a nearby candidate of an advanced remnant of such a merger, showing typical tidal structures such as an optical tail and two shells as well as two H i tails. Aims: Studying the molecular gas content provides clues about the impact of a recent merger event on the star formation. Simulations of S+E mergers yield conflicting predictions about both the strength and the extent of an induced starburst. Thus, observations of the amount and the distribution of the molecular gas, the raw material of star formation, are needed to understand the influence of the merger on the star formation history. Methods: 12CO and 13CO (1-0) and (2-1) observations were obtained using the Onsala Space Observatory 20 m and IRAM 30 m telescope as well as the Plateau de Bure interferometer. These data allow us to carry out a basic analysis of the molecular gas properties, such as estimates of the molecular gas mass, temperature, and density and the star formation efficiency. Results: The CO observations detect an extended molecular gas reservoir out to ~4 kpc, with a total molecular gas mass of ˜5 × 10^8~M?. Furthermore, high resolution imaging shows a central molecular gas feature, which is probably a rotating disc hosting most of the molecular gas (˜4 × 10^8~M?). This nuclear disc has a different sense of rotation to the large-scale H i structure, indicating a kinematically decoupled core. We modeled the state of the interstellar medium with the radiative transfer code RADEX, using the ratios of the 12CO to 13CO line strenghts. The results are consistent with a diffuse (n? 10^3 cm-3) molecular medium with no significant indications of cold, dense cores of ongoing star formation. This is in agreement with the moderate star formation rate of 1-2~M?~yr-1 measured for NGC 4441. Assuming a constant star formation rate, the gas depletion time is ? = 4.8 ×108 yr. NGC 4441 might be a nearby candidate early-type galaxy with a dominant A-star population, a so-called E+A galaxy, which is in a post-starburst phase several 108 yr after a merger event.

Jütte, E.; Aalto, S.; Hüttemeister, S.

2010-01-01

406

Microbial diversity in soil: ecological theories, the contribution of molecular techniques and the impact of transgenic plants and transgenic microorganisms  

Microsoft Academic Search

This review mainly discusses three related topics: the application of ecological theories to soil, the measurement of microbial diversity by molecular techniques and the impact of transgenic plants and microorganisms on genetic diversity of soil. These topics were debated at the Meeting on Soil Emergency held in Erice (Trapani, Italy) in 2001 for the celebration of the 50th anniversary of

J. M. Lynch; A. Benedetti; H. Insam; M. P. Nuti; K. Smalla; V. Torsvik; P. Nannipieri

2004-01-01

407

Recent developments in molecular techniques for identification and monitoring of xenobiotic-degrading bacteria and their catabolic genes in bioremediation  

Microsoft Academic Search

The pollution of soil and water with xenobiotics is widespread in the environment and is creating major health problems. The utilization of microorganisms to clean up xenobiotics from a polluted environment represents a potential solution to such environmental problems. Recent developments in molecular-biology-based techniques have led to rapid and accurate strategies for monitoring, discovery and identification of novel bacteria and

J. Widada; H. Nojiri; T. Omori

2002-01-01

408

Coupling of gas chromatography and molecular beam\\/mass spectrometry analytical techniques: Application to flame structure study  

Microsoft Academic Search

A new experimental technique coupling both molecular beam and mass spectrometry (MBMS) and gas chromatography (GC) is developed to improve the analysis of low pressure reactive systems using a probe sampling procedure. The sensitivity of gas chromatography is greatly enhanced by using a compression procedure for the samples before injection into the chromatograph, and its selectivity allows one to separate

A. Turbiez; P. Devynck; P. Desgroux; J. F. Pauwels

1999-01-01

409

Investigation of lichens using molecular techniques and associated mineral accumulations on a basaltic flow in a Mediterranean environment  

Microsoft Academic Search

The role of lichens in the breakdown of rocks in various environments is well documented. We investigated the formation of secondary minerals under 13 different fungal species growing on a basaltic flow in Sanliurfa (Turkey) to understand the influence of lichen species on the transformation of minerals in a Mediterranean environment. We used molecular technique (rDNA sequence) to identify 13

Joselito M. Arocena; Tariq Siddique; Ronald W. Thring; Selim Kapur

2007-01-01

410

Simultaneous Measurements of Droplet Size and Temperature Distribution Within a Water Droplet by using Molecular Tagging Thermometry Technique  

Microsoft Academic Search

We present the research progress made in developing and implementing a novel lifetime-based molecular tagging thermometry (MTT) technique for achieving simultaneous measurements of droplet size and spatially-and-temporally resolved temperature distribution within small water droplets over solid surfaces for aircraft icing studies. For MTT measurement, a pulsed laser is used to \\

Hui Hu; De Huang

411

The advancing identification and classification of Rhizoctonia spp. using molecular and biotechnological methods compared with the classical anastomosis grouping  

Microsoft Academic Search

Anamorphic classification of Rhizoctonia spp. has been based on young cell nuclear numbers and hyphal fusion to anastomosis groups (AGs), in addition to the teleomorph\\u000a classification. The widespread development of molecular biology techniques has added modern tools to support classification\\u000a of organisms according to their genetics and evolutionary processes. These various methods have also been used in recent years\\u000a for

Michal Sharon; Shiro Kuninaga; Mitsuro Hyakumachi; Baruch Sneh

2006-01-01

412

Head up and head mounted display performance improvements through advanced techniques in the manipulation of light  

NASA Astrophysics Data System (ADS)

Since their introduction a number of years ago, head up and helmet mounted displays have undergone continuous and intensive development in aerospace applications. To date, the designs have been performed using geometric optic design techniques and have progressed to the point where very little further improvement in their characteristics is possible. This paper describes a display realised by the use of new optical design techniques based on wave-guiding principles that have enabled substantial further significant improvements to be made. These improvements are not only in respect of size, weight and volume for a given optical performance, but also in the optical characteristics that currently limit the usability of such displays in many applications. Displays that have been realised and tested through these methods are described and their performance in laboratory and flight trials discussed, together with considerations for further progress in their development.

Wisely, Paul L.

2009-05-01

413

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

414

Development of laser spectroscopic diagnostics to support advanced compound semiconductor deposition techniques  

NASA Astrophysics Data System (ADS)

This program constructed and demonstrated an apparatus for the development of laser diagnostics for the gas phase molecules involved in semiconductor fabrication techniques, particularly the organometallic chemical vapor deposition of compound semiconductors like gallium arsenide. Work on this apparatus, a flow tube with mirrors for long path tunable infrared diode laser absorption and electrodes for a radio frequency glow discharge, culminated in observations designed to assess the importance of arsenic hydride radicals in the decomposition of organoarsenic compounds. Preliminary observations of fluorocarbon and methane plasmas produced observations of several species which could be compared with models and other observations and which added to knowledge of these systems with their important applications in silicon etching an diamond deposition. The program also resulted in band strength measurements for the methyl and difluorocarbene radicals, using tunable diode laser, dye laser, and fast flow reactor techniques.

Wormhoudt, Joda C.

1990-07-01

415

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

416

Recent advances in cell micropatterning techniques for bioanalytical and biomedical sciences.  

PubMed

Cell micropatterning is an important technique for a wide range of applications, such as tissue engineering, cell-based drug screening, and fundamental cell biology studies. This paper overviews cell patterning techniques based on chemically modified substrates with different degrees of cell adhesiveness. In particular, the focus is on dynamic substrates that change their cell adhesiveness in response to external stimuli, such as heat, voltage, and light. Such substrates allow researchers to achieve an in situ alteration of patterns of cell adhesiveness, which is useful for co-culturing multiple cell types and analyzing dynamic cellular activities. As an example of dynamic substrates, we introduce a dynamic substrate based on a caged compound, where we accomplished a light-driven alteration of cell adhesiveness and the analysis of a single cell's motility. PMID:18187851

Nakanishi, Jun; Takarada, Tohru; Yamaguchi, Kazuo; Maeda, Mizuo

2008-01-01

417

Advances in the embedded-strain-gage technique with an application to contact problems  

Microsoft Academic Search

Improvements in the embedded-strain-gage technique for the measurement of strains at internal points in models of machine\\u000a components are described. A New measurement module permits an experimental determination of the strain in models of epoxy\\u000a resin. By its construction, the centers of the rosettes may be accurately located in the model mold, before casting. A large\\u000a number of gages may

M. Derenne; A. Bazergui

1971-01-01

418

Detection of premalignant bronchial lesions can be significantly improved by combination of advanced bronchoscopic imaging techniques  

PubMed Central

BACKGROUND: The search for the most efficient bronchoscopic imaging tool in detection of early lung cancer is still active. The major aim of this study was to determine sensitivity, specificity, positive predictive value (PPV), and negative predictive value (NPV) of each bronchoscopic technique and their combination in detection of premalignant bronchial lesions. METHODS: This was a prospective trial that enrolled 96 patients with indication for bronchoscopy. Lesions were classified as visually positive if pathological fluorescence was observed under autofluorescence imaging (AFI) videobronchoscopy or dotted, tortuous, and abrupt-ending blood vessels were identified under narrow band imaging (NBI) videobronchoscopy. Squamous metaplasia, mild, moderate, or severe dysplasia, and carcinoma in situ (CIS) were regarded as histologically positive lesions. RESULTS: Sensitivity, specificity, PPV, and NPV of white light videobronchoscopy (WLB) in detection of premalignant lesions were 26.5%, 63.9%, 34.4%, and 54.9%, respectively; the corresponding values for AFI were 52%, 79.6%, 64.6%, and 69.9% respectively, for NBI were 66%, 84.6%, 75.4%, 77.7%, respectively, while the values for combination of NBI and AFI were 86.1%, 86.6%, 84.6%, and 88%, respectively. Combination of NBI and AFI significantly improves sensitivity when compared to each individual technique (P < 0.001). When specificity is of concern, combination of techniques improves specificity of WLB (P < 0.001) and specificity of AFI (P = 0.03), but it does not have significant influence on specificity of NBI (P = 0.53). CONCLUSION: Combination of NBI and AFI in detection of premalignant bronchial lesions increases both sensitivity and specificity of each technique. However, it seems that NBI is most sufficient and effective in detection of these lesions.

Zaric, Bojan; Perin, Branislav; Stojsic, Vladimir; Carapic, Vladimir; Matijasevic, Jovan; Andrijevic, Ilija; Eri, Zivka

2013-01-01

419

Carbon dioxide capture and separation techniques for advanced power generation point sources  

Microsoft Academic Search

The capture\\/separation step for carbon dioxide (CO2) from large-point sources is a critical one with respect to the technical feasibility and cost of the overall carbon sequestration scenario. For large-point sources, such as those found in power generation, the carbon dioxide capture techniques being investigated by the in-house research area of the National Energy Technology Laboratory possess the potential for

H. W. Pennline; D. R. Luebke; B. I. Morsi; Y. J. Heintz; K. L. Jones; J. B. Ilconich

2006-01-01

420

Analysis of liquid penetration in paper structures by advanced imaging techniques  

NASA Astrophysics Data System (ADS)

Ink penetration in paper is influenced by the structure of the interfiber and intrafiber void spaces and the surface characteristics of the fibers. This dissertation describes new techniques to determine the influence of the fiber surfaces and the cell wall internal structure on ink spreading and penetration. The location and penetration of ink is demonstrated by optical, scanning electron, confocal laser scanning, and transmission electron (TEM) microscopy methods. Ink penetration, as determined by each of these methods, is compared. The hemicelluloses of the fiber's internal void surfaces can be determined by immunochemical labeling in conjunction with TEM imaging. It is demonstrated through the use of primary monoclonal antibodies with specificity for hemicelluloses with a secondary colloidal gold marker. This technique provides a way to visualize the location of hemicelluloses inside the cell wall and on the surfaces of nanopores. Combining paper structure with fluid spreading and wicking models can identify the influence of fiber surfaces and the cell wall on drop absorption. Ink spreading coefficients for such modeling are determined through a series of designed experiments (DoE) and comparisons to a theoretical sessile drop. Application: Microscopic techniques used to determine biological and physical locations in plants on a fibrous level also can be used to study ink diffusion, water uptake, and other characteristics of fibrous material. Key Words: Immunolableing of hemicelluloses, DoE, drop spread modeling, ink diffusion.

Arthur, Beth Ann

421

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

422

Advances in techniques for the ultrasonic monitoring of the cleanliness of steel  

NASA Astrophysics Data System (ADS)

Ultrasonic techniques are of considerable interest in characterizing the cleanliness of steel billet. As compared to metallographic techniques, their ability to rapidly sample significant volumes of material in a nondestructive fashion is particularly attractive. A recent set of results is described in which physically based models of the ultrasonic inspection are used to guide technique optimization. Models are used for three purposes. Beam models are used to select transducer parameters which will be minimally affected by the cylindrical geometry of the billet surface, which defocusses the beam in a plane perpendicular to the billet axis. Flaw response models are used to predict the strength of signals from undesirable inclusions, in particular those consisting of highly brittle material such as alumina which can lead to premature failure. For microstructures of a given type and grain size, microstructural response models are used to predict grain noise levels which in turn lead to estimates of the minimum detectable inclusion size. This information can be used to guide pre-inspection heat treatment. As an example of the integrated use of these tools, the design of a system to inspect 3 inch diameter billet used for the manufacture of gears will be discussed.-This work was supported by the NSF Industry/University Cooperative Research program. .

Guo, Y.; Spore, C.; Margetan, F. J.; Thompson, R. B.; Ahmad, A.

2000-05-01

423

"Tubeless" percutaneous surgery: a new advance in the technique of percutaneous renal surgery.  

PubMed

We describe our modification of the technique of traditional percutaneous renal surgery called "tubeless" percutaneous renal surgery. Fifty patients have now undergone percutaneous renal procedures without the use of a postoperative nephrostomy tube consisting of percutaneous nephrolithotripsy, percutaneous endopyelotomy, and both percutaneous stone extraction and endopyelotomy in the same setting. Our current modification of standard percutaneous surgical technique includes the placement of an internal ureteral catheter with primary closure of the access site using hemostatic skin sutures. The study group was compared to a control group of 50 patients who were age, sex and procedure matched who had undergone standard percutaneous renal procedures previously with routine placement of postoperative nephrostomy tubes. The incidence of complications, analgesia requirements, length of hospitalization, time of return to normal activities, and cost of treatment were compared between the two groups. All tubeless percutaneous procedures were successfully performed without significant complications. The initial 15 patients had postoperative renal ultrasounds demonstrating no urinoma. Hospital stay, analgesia requirements, and the patient's ability to return to normal activities were statistically significantly decreased in the patient group studied. The cost of a "tubeless" procedure was $1,638 compared with $3,750 (129% greater) for traditional percutaneous surgery (cost saving of $2,112/case). Tubeless percutaneous renal surgery is a safe procedure and offers advantages over the routine placement of a nephrostomy tube. The hospitalization period, analgesia requirements, return to normal activities, and cost are significantly less with this new technique. PMID:9170218

Candela, J; Davidoff, R; Gerspach, J; Bellman, G C

1997-01-01

424

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

425

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

426

NATO Advanced Research Workshop on Non-Thermal Plasma Techniques for Pollution Control  

NASA Astrophysics Data System (ADS)

Acid rain, global warming, ozone depletion, and smog are preeminent environmental problems facing the world today. Non-thermal plasma techniques offer an innovative approach to the cost-effective solution of these problems. Many potential applications of non-thermal plasmas to air pollution control have already been demonstrated. On 21-25 Sept. 1992, leading experts from academia, government laboratories, and industry met at Cambridge University, England to discuss laboratory studies and industrial implementation of non-thermal plasmas for the abatement of hazardous gaseous wastes. Papers presented at the workshop are included.

1992-09-01

427

Studies and advances on joint source-channel encoding\\/decoding techniques in flow media communications  

Microsoft Academic Search

Joint source-channel coding\\/decoding (JSCC\\/JSCD) techniques in flow media communications have become a state-of-the-art and\\u000a one of the challenging research subjects in the spatial communication area. They have great application prospective and deep\\u000a impact in various manned space flights, satellite missions, mobile radio communications and deep-space explorations. In the\\u000a last few years, there have been influential achievements in JSCC\\/JSCD studies. This

Guofang Tu; Jianjun Liu; Can Zhang; Shaoshuai Gao; Shidong Li

2010-01-01

428

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

2012-06-18

429

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

2012-12-03

430

An educational training simulator for advanced perfusion techniques using a high-fidelity virtual patient model.  

PubMed

The operation of cardiopulmonary bypass procedure requires an advanced skill in both physiological and mechanical knowledge. We developed a virtual patient simulator system using a numerical cardiovascular regulation model to manage perfusion crisis. This article evaluates the ability of the new simulator to prevent perfusion crisis. It combined short-term baroreflex regulation of venous capacity, vascular resistance, heart rate, time-varying elastance of the heart, and plasma-refilling with a simple lumped parameter model of the cardiovascular system. The combination of parameters related to baroreflex regulation was calculated using clinical hemodynamic data. We examined the effect of differences in autonomous-nerve control parameter settings on changes in blood volume and hemodynamic parameters and determined the influence of the model on operation of the control arterial line flow and blood volume during the initiation and weaning from cardiopulmonary bypass. Typical blood pressure (BP) changes (hypertension, stable, and hypotension) were reproducible using a combination of four control parameters that can be estimated from changes in patient physiology, BP, and blood volume. This simulation model is a useful educational tool to learn the recognition and management skills of extracorporeal circulation. Identification method for control parameter can be applied for diagnosis of heart failure. PMID:22963152

Tokaji, Megumi; Ninomiya, Shinji; Kurosaki, Tatsuya; Orihashi, Kazumasa; Sueda, Taijiro

2012-09-11

431

Advances in fluorescence imaging techniques to detect oral cancer and its precursors  

PubMed Central

Oral cancer is a significant health problem in the USA and throughout the world. Most oral cancer patients are diagnosed at a late stage, when treatment is less successful and treatment-associated morbidity is more severe. A number of new diagnostic aids to conventional oral examination have recently been introduced to assist in the early detection of oral neoplasia. In particular, autofluorescence imaging has emerged as a promising adjunctive technique to improve early identification of oral premalignant lesions. Direct visual inspection of tissue autofluorescence has shown encouraging results in high-prevalence populations, but the technique requires subjective interpretation and depends on the visual recognition skills of the examiner. Capturing and analyzing digital fluorescence images can reduce subjectivity and potentially improve sensitivity of detection of precancerous changes. Recent studies of wide-field autofluorescence imaging in low-prevalence populations suggest that benign lesions such as inflammation may give rise to false-positive results. High-resolution fluorescence imaging is a new modality that can be used in conjunction with wide-field imaging to improve specificity by imaging subcellular detail of neoplastic tissues. The combination of wide-field and high-resolution fluorescence imaging systems with automated image analysis should be investigated to maximize overall diagnostic performance for early detection of oral neoplasia.

Shin, Dongsuk; Vigneswaran, Nadarajah; Gillenwater, Ann; Richards-Kortum, Rebecca

2010-01-01

432

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.

2004-10-01

433

In vitro testicular toxicity models: opportunities for advancement via biomedical engineering techniques.  

PubMed

To address the pressing need for better in vitro testicular toxicity models, a workshop sponsored by the International Life Sciences Institute (ILSI), the Health and Environmental Science Institute (HESI), and the Johns Hopkins Center for Alternatives to Animal Testing (CAAT), was held at the Mt. Washington Conference Center in Baltimore, MD, USA on October 26-27, 2011. At this workshop, experts in testis physiology, toxicology, and tissue engineering discussed approaches for creating improved in vitro environments that would be more conducive to maintaining spermatogenesis and steroidogenesis and could provide more predictive models for testicular toxicity testing. This workshop report is intended to provide scientists with a broad overview of relevant testicular toxicity literature and to suggest opportunities where bioengineering principles and techniques could be used to build improved in vitro testicular models for safety evaluation. Tissue engineering techniques could, conceivably, be immediately implemented to improve existing models. However, it is likely that in vitro testis models that use single or multiple cell types will be needed to address such endpoints as accurate prediction of chemically induced testicular toxicity in humans, elucidation of mechanisms of toxicity, and identification of possible biomarkers of testicular toxicity. PMID:23861079

Parks Saldutti, Louise; Beyer, Bruce K; Breslin, William; Brown, Terry R; Chapin, Robert E; Campion, Sarah; Enright, Brian; Faustman, Elaine; Foster, Paul M D; Hartung, Thomas; Kelce, William; Kim, James H; Loboa, Elizabeth G; Piersma, Aldert H; Seyler, David; Turner, Katie J; Yu, Hanry; Yu, Xiaozhong; Sasaki, Jennifer C

2013-01-01

434

Advanced numerical techniques for accurate unsteady simulations of a wingtip vortex  

NASA Astrophysics Data System (ADS)

A numerical technique is developed to simulate the vortices associated with stationary and flapping wings. The Unsteady Reynolds-Averaged Navier-Stokes (URANS) equations are used over an unstructured grid. The present work assesses the locations of the origins of vortex generation, models those locations and develops a systematic mesh refinement strategy to simulate vortices more accurately using the URANS model. The vortex center plays a key role in the analysis of the simulation data. A novel approach to locating a vortex center is also developed referred to as the Max-Max criterion. Experimental validation of the simulated vortex from a stationary NACA0012 wing is achieved. The tangential velocity along the core of the vortex falls within five percent of the experimental data in the case of the stationary NACA0012 simulation. The wing surface pressure coefficient also matches with the experimental data. The refinement techniques are then focused on unsteady simulations of pitching and dual-mode wing flapping. Tip vortex strength, location, and wing surface pressure are analyzed. Links to vortex behavior and wing motion are inferred. Key words: vortex, tangential velocity, Cp, vortical flow, unsteady vortices, URANS, Max-Max, Vortex center

Ahmad, Shakeel

435

Structural changes of humic acids from sinking organic matter and surface sediments investigated by advanced solid-state NMR: Insights into sources, preservation and molecularly uncharacterized components  

NASA Astrophysics Data System (ADS)

Knowledge of the structural changes that particulate organic matter (POM) undergoes in natural systems is essential for determining its reactivity and fate. In the present study, we used advanced solid-state NMR techniques to investigate the chemical structures of sinking particulate matter collected at different depths as well as humic acids (HAs) extracted from these samples and underlying sediments from the Saguenay Fjord and the St. Lawrence Lower Estuary (Canada). Compared to bulk POM, HAs contain more non-polar alkyls, aromatics, and aromatic C-O, but less carbohydrates (or carbohydrate-like structures). In the two locations studied, the C and N contents of the samples (POM and HAs) decreased with depth and after deposition onto sediments, leaving N-poor but O-enriched HAs and suggesting the involvement of partial oxidation reactions during POM microbial degradation. Advanced NMR techniques revealed that, compared to the water-column HAs, sedimentary HAs contained more protonated aromatics, non-protonated aromatics, aromatic C-O, carbohydrates (excluding anomerics), anomerics, OCq, O-Cq-O, OCH, and OCH3 groups, but less non-polar alkyls, NCH, and mobile CH2 groups. These results are consistent with the relatively high reactivity of lipids and proteins or peptides. In contrast, carbohydrate-like structures were selectively preserved and appeared to be involved in substitution and copolymerization reactions. Some of these trends support the selective degradation (or selective preservation) theory. The results provide insights into mechanisms that likely contribute to the preservation of POM and the formation of molecules that escape characterization by traditional methods. Despite the depletion of non-polar alkyls with depth in HAs, a significant portion of their general structure survived and can be assigned to a model phospholipid. In addition, little changes in the connectivities of different functional groups were observed. Substituted and copolymerized carbohydrates and fused-ring aromatics detected in the present study likely represented an important part of molecularly uncharacterized components (MUC).

Mao, Jingdong; Tremblay, Luc; Gagné, Jean-Pierre

2011-12-01

436

Research Advances: Nanoscale Molecular Tweezers; Cinnamon as Pesticide?; Recently Identified Dietary Sources of Antioxidants  

NASA Astrophysics Data System (ADS)

This Report from Other Journals surveys articles of interest to chemists that have been recently published in other science journals. Topics surveyed include reports that receptors have been designed to act as molecular tweezers; cinnamon has potential in the fight against mosquitoes; and high levels of antioxidants are found in some surprising foods. See Featured Molecules .

King, Angela G.

2004-12-01

437

SOFTWARE REVIEW: The Advanced Physics Virtual Laboratory Series: CD-ROM Thermodynamics and Molecular Physics  

Microsoft Academic Search

The program installed easily although the inexperienced might be as terrified as I was by the statements threatening to delete various files it had found on my machine. However, I ignored these and all went well. The user is faced with a menu of 14 simulations covering molecular topics such as the Kinetic Model of an Ideal Gas, Diffusion (through

Ken Dobson

1998-01-01

438

Next Generation of Risk Assessment: Incorporation of Recent Advances in Molecular, Computational and Systems Biology  

EPA Science Inventory

The Next Generation (NexGen) Risk Assessment program was initiated in 2010 as a multi-year, multi-organization effort to consider new molecular, computational, and systems biology approaches for use in risk assessments. The goal is to enable faster, less expensive, and more robus...

439

Individual classification of ADHD patients by integrating multiscale neuroimaging markers and advanced pattern recognition techniques  

PubMed Central

Accurate classification or prediction of the brain state across individual subject, i.e., healthy, or with brain disorders, is generally a more difficult task than merely finding group differences. The former must be approached with highly informative and sensitive biomarkers as well as effective pattern classification/feature selection approaches. In this paper, we propose a systematic methodology to discriminate attention deficit hyperactivity disorder (ADHD) patients from healthy controls on the individual level. Multiple neuroimaging markers that are proved to be sensitive features are identified, which include multiscale characteristics extracted from blood oxygenation level dependent (BOLD) signals, such as regional homogeneity (ReHo) and amplitude of low-frequency fluctuations. Functional connectivity derived from Pearson, partial, and spatial correlation is also utilized to reflect the abnormal patterns of functional integration, or, dysconnectivity syndromes in the brain. These neuroimaging markers are calculated on either voxel or regional level. Advanced feature selection approach is then designed, including a brain-wise association study (BWAS). Using identified features and proper feature integration, a support vector machine (SVM) classifier can achieve a cross-validated classification accuracy of 76.15% across individuals from a large dataset consisting of 141 healthy controls and 98 ADHD patients, with the sensitivity being 63.27% and the specificity being 85.11%. Our results show that the most discriminative features for classification are primarily associated with the frontal and cerebellar regions. The proposed methodology is expected to improve clinical diagnosis and evaluation of treatment for ADHD patient, and to have wider applications in diagnosis of general neuropsychiatric disorders.

Cheng, Wei; Ji, Xiaoxi; Zhang, Jie; Feng, Jianfeng

2012-01-01

440

Beam profile measurements on the advanced test accelerator using optical techniques  

SciTech Connect

Beam current density profiles of ATA have been measured both spatially and temporally using a number of diagnostics. An extremely important technique involves measuring optical emissions from either a target foil inserted into the beam path or gas atoms and molecules excited by beam electrons. This paper describes the detection of the optical emission. A 2-D gated television camera with a single or dual micro-channel-plate (MCP) detector for